data/chunks/chunk_a71f59bd_14.jsonl

{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 255, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in structural steelwork to BS 5950\n234\nSize or\nleg length\nThroat\n(b)\n(a)\nThroat\nFig. 4.57 Types of weld; (a) butt weld; ( b) fillet weld.\n4.11.5 WELDED CONNECTIONS\nThe two main types of welded joints are fillet welds\nand butt welds. Varieties of each type are shown\nin Fig. 4.57. Essentially the process of welding con-\nsists of heating and melting steel in and/or around\nthe gap between the pieces of steel that are being\nwelded together. Welding rods consist of a steel\nrod surrounded by a flux which helps the metal to\nmelt and flow into the joint. Welding can be ac-\ncomplished using oxy-acetylene equipment, but the\neasiest method uses electric arc welding.\n4.11.5.1 Strength of welds\nIf welding is expertly carried out using the correct\ngrade of welding rod, the resulting weld should be\nconsiderably stronger than the pieces held together.\nHowever, to allow for some variation in the quality\nof welds, it is assumed that the weld strength for\nfillet welds is as given in Table 37 of BS 5950,\nreproduced below as Table 4.25.\nHowever, the design strength of the weld can be\ntaken as the same as that for the parent metal if the\njoint is a butt weld, or alternatively a fillet weld\nsatisfying the following conditions:\n1. The weld is symmetrical as shown in Fig.\n4.58.\n2. It is made with suitable electrodes which will\nproduce specimens at least as strong as the par-\nent metal.\n3. The sum of throat sizes (Fig. 4.58) is not less\nthan the connected plate thickness.\n4. The weld is principally subject to direct tension\nor compression (Fig. 4.58).\n4.11.5.2 Design details\nFigure 4.57 also indicates what is meant by the\nweld leg length, s, and the effective throat size,\na, which should not be taken as greater than\n0.7s.\nFig. 4.58 Special fillet weld.\nTable 4.25\nDesign strength of fillet welds, pw\n(Table 37, BS 5950)\nSteel grade\nElectrode classification\n35\n42\n50\nN/mm2\nN/mm2\nN/mm2\nS275\n220\n220a\n220a\nS355\n220b\n250\n250a\nS460\n220b\n250b\n280\nNotes. a Over matching electrodes.\nb Under matching electrodes. Not to be used for partial\npenetration butt welds.\nt\nThroat a\n\n[TABLES]\n[[{\"0\": \"Fig. 4.57 Types of weld; (a) butt weld; ( b) fillet weld.\", \"1\": \"\"}, {\"0\": \"4.11.5 WELDED CONNECTIONS\", \"1\": \"However, the design strength of the weld can be\"}, {\"0\": \"The two main types of welded joints are fillet welds\", \"1\": \"taken as the same as that for the parent metal if the\"}, {\"0\": \"and  butt  welds.  Varieties  of  each  type  are  shown\", \"1\": \"joint  is  a  butt  weld,  or  alternatively  a  fillet  weld\"}, {\"0\": \"in Fig. 4.57. Essentially the process of welding con-\", \"1\": \"satisfying the following conditions:\"}, {\"0\": \"sists of heating and melting steel in and/or around\", \"1\": \"1. The  weld is symmetrical  as shown in  Fig.\"}, {\"0\": \"the  gap  between  the  pieces  of  steel  that  are  being\", \"1\": \"4.58.\"}, {\"0\": \"welded  together.  Welding  rods  consist  of  a  steel\", \"1\": \"2.It  is  made  with  suitable  electrodes  which  will\"}, {\"0\": \"rod surrounded by a flux which helps the metal to\", \"1\": \"produce specimens at least as strong as the par-\"}, {\"0\": \"melt  and  flow  into  the  joint.  Welding  can  be  ac-\", \"1\": \"ent metal.\"}, {\"0\": \"complished using oxy-acetylene equipment, but the\", \"1\": \"3. The  sum  of  throat  sizes  (Fig.  4.58)  is  not  less\"}, {\"0\": \"easiest method uses electric arc welding.\", \"1\": \"than the connected plate thickness.\"}, {\"0\": \"4.11.5.1 Strength of welds\", \"1\": \"4. The weld is principally subject to direct tension\"}, {\"0\": \"If welding is expertly carried out using the correct\", \"1\": \"or compression (Fig. 4.58).\"}, {\"0\": \"grade of welding rod, the resulting weld should be\", \"1\": \"\"}, {\"0\": \"considerably stronger than the pieces held together.\", \"1\": \"4.11.5.2 Design details\"}, {\"0\": \"However, to allow for some variation in the quality\", \"1\": \"Figure  4.57  also  indicates  what  is  meant  by  the\"}, {\"0\": \"of  welds,  it  is  assumed  that  the  weld  strength  for\", \"1\": \"weld leg length, s, and the effective throat size,\"}, {\"0\": \"fillet  welds  is  as  given  in  Table  37  of  BS  5950,\", \"1\": \"a,  which  should  not  be taken  as  greater than\"}, {\"0\": \"reproduced below as Table 4.25.\", \"1\": \"0.7s.\"}], [{\"0\": \"(Table 37, BS 5950)\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}, {\"0\": \"Steel grade\", \"1\": \"\", \"2\": \"Electrode classification\", \"3\": \"\"}, {\"0\": \"\", \"1\": \"35\", \"2\": \"42\", \"3\": \"50\"}, {\"0\": \"\", \"1\": \"N/mm2\", \"2\": \"N/mm2\", \"3\": \"N/mm2\"}, {\"0\": \"S275\", \"1\": \"220\", \"2\": \"220a\", \"3\": \"220a\"}, {\"0\": \"S355\", \"1\": \"220b\", \"2\": \"250\", \"3\": \"250a\"}, {\"0\": \"S460\", \"1\": \"220b\", \"2\": \"250b\", \"3\": \"280\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0255.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 256, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n235\nDesign of connections\nThe effective length of a run of weld should be\ntaken as the actual length, less one leg length for\neach end of the weld. Where the weld ends at a corner\nof the metal, it should be continued around the\ncorner for a distance greater than 2s. In a lap joint,\nthe minimum lap length should be not less than 4t,\nwhere t is the thinner of the pieces to be joined.\nFor fillet welds, the ‘vector sum of the design\nstresses due to all forces and moments transmitted\nby the weld should not exceed the design strength, pw’.\nExample 4.25 Analysis of a welded beam-to-column connection\n(BS 5950)\nA grade S275 steel 610 × 229 × 101 UB is to be connected, via a welded end plate onto a 356 × 368 × 177 UC. The\nconnection is to be designed to transmit a bending moment of 500 kN m and a shear force of 300 kN. Show that the\nproposed welding scheme for this connection is adequate.\nBeam\n15 mm\nend plate\nElevation\nColumn\n356 × 368 × 177 UC\n610 × 229 × 101 UB\n15 mm stiffeners\nPlan\nEnd view\nElectrode strength\n42\n10 mm fillet welds\n10 mm fillet welds\n225\ny\ny1\nx\nx\ny\n570\n587\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"\", \"2\": \"610 × 229 × 101 UBBeam15 mmend plate15 mm stiffeners\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"356 × 368 × 177 UCColumn\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}], [{\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"42\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0256.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 257, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in structural steelwork to BS 5950\n236\n4.12 Summary\nThis chapter has considered the design of a number\nof structural steelwork and composite elements,\nincluding beams, slabs, columns and connections,\nto BS 5950: Structural use of steel work in buildings.\nThe ultimate limit state of strength and the\nserviceability limit state of deflection principally\ninfluence the design of steel elements. Many steel\nstructures are still analaysed by assuming that\nindividual elements are simply supported at their\nends. Steel sections are classified as plastic, compact,\nsemi-compact or slender depending on how the\nsections perform in bending. The design of flexural\nmembers generally involves considering the limit\nstates of bending, shear, web bearing/buckling,\ndeflection and if the compression flange is not fully\nrestrained, lateral torsional buckling. Columns sub-\nject to axial load and bending are normally checked\nfor cross-section capacity and buckling resistance.\nThe two principal methods of connecting steel\nelements of a structure are bolting and welding. It\nis vitally important that the joints are designed to\nact in accordance with the assumptions made in\nthe design. Design of bolted connections, using\nordinary (or black) bolts, usually involves check-\ning that neither the bolt nor the elements being\njoined exceed their shear, bearing or tension\ncapacities. Where HSFG bolts are used, the slip\nresistance must also be determined. Welded con-\nnections are most often used to weld end plates\nor cleats to members, a task which is normally\nperformed in the fabrication yard rather than on\nsite.\nExample 4.25 continued\nLeg length of weld, s = 10 mm. Effective length of weld is\n4(bw − 2s) + 2(hw − 2s) = 4(225 − 2 × 10) + 2(570 − 2 × 10) = 1920 mm\n  \nWeld force\nshear force\neffective length of weld\n kN/mm\n  \n  \n  .\n=\n=\n=\n300\n1920\n0 16\nWeld second moment of area, Ixx, is\nIxx = 4[1 × (Bw − 2s)]y2\n1 + 2[1 × (hw − 2s)3/12]\n  =\n+\n×\n [(\n)]\n.\n  [   (\n) /\n]\n4 205 293 5\n21\n550\n12\n2\n3\n= 98 365 812 mm4\nWeld shear (moment) is\n    \nMy\nIxx\nkN/mm\n  \n  \n  \n.   .\n \n=\n×\n×\n=\n500\n10\n293 5\n98 365 812\n1 49\n3\nwhere y = D/2 = 587/2 = 293.5 mm\nVectored force =   1 49\n0 16\n2\n2\n.\n  .\n+\n = 1.50 kN/mm\nSince the steel grade is S275 and the electrode strength is 42, the design strength of the weld is 220 N/mm2\n(Table 4.25).\nWeld capacity of 10 mm fillet weld, pwc, is\npwc = apw = 0.7 × 10 × 220 × 10−3 = 1.54 kN/mm > 1.50 kN/mm\nOK\nwhere throat thickness of weld, a = 0.7s = 0.7 × 10 mm\nHence proposed welding scheme is just adequate.\n\n[TABLES]\n[[{\"0\": \"Design in structural steelwork to BS 5950\"}, {\"0\": \"Example 4.25 continued\"}, {\"0\": \"Leg length of weld, s = 10 mm. Effective length of weld is\"}, {\"0\": \"4(bw − 2s) + 2(h w − 2s) = 4(225 − 2 × 10) + 2(570 − 2 × 10) = 1920 mm\"}, {\"0\": \"shear force300===Weld force      0 16 kN/mm\"}, {\"0\": \"effective length of weld1920\"}, {\"0\": \"Weld second moment of area, Ixx, is\"}, {\"0\": \"Ixx = 4[1 × (Bw − 2s)]y 21 + 2[1 × (hw − 2s)3/12]\"}, {\"0\": \"23=+× 4[(205 293 5  2 1 (550)/12]\"}, {\"0\": \"= 98 365 812 mm4\"}, {\"0\": \"Weld shear (moment) is\"}, {\"0\": \"3××My500  10  293 5==\"}, {\"0\": \"1 49 kN/mm98 365 812Ixx\"}, {\"0\": \"where y = D/2 = 587/2 = 293.5 mm\"}, {\"0\": \"22+  0 16 = 1.50 kN/mmVectored force =    1 49\"}, {\"0\": \"Since  the  steel  grade  is  S275  and  the  electrode  strength  is  42,  the  design  strength  of  the  weld  is  220  N/mm2\"}, {\"0\": \"(Table 4.25).\"}, {\"0\": \"Weld capacity of 10 mm fillet weld, pwc, is\"}, {\"0\": \"OKpwc = apw = 0.7 × 10 × 220 × 10−3 = 1.54 kN/mm > 1.50 kN/mm\"}, {\"0\": \"where throat thickness of weld, a = 0.7s = 0.7 × 10 mm\"}, {\"0\": \"Hence proposed welding scheme is just adequate.\"}, {\"0\": \"restrained, lateral torsional buckling. Columns sub- 4.12 Summary\"}, {\"0\": \"ject to axial load and bending are normally checked\"}, {\"0\": \"This chapter has considered the design of a numberfor cross-section capacity and buckling resistance.\"}, {\"0\": \"of  structural  steelwork  and  composite  elements,The  two  principal  methods  of  connecting  steel\"}, {\"0\": \"including beams, slabs, columns and connections,elements of a structure are bolting and welding. It\"}, {\"0\": \"to BS 5950: Structural use of steel work in buildings.is  vitally  important  that  the  joints  are  designed  to\"}, {\"0\": \"The  ultimate limit state  of strength and theact  in  accordance  with  the  assumptions  made  in\"}, {\"0\": \"serviceability limit  state  of  deflection  principallythe  design.  Design  of  bolted  connections,  using\"}, {\"0\": \"influence  the  design  of  steel  elements.  Many  steelordinary  (or  black)  bolts,  usually  involves  check-\"}, {\"0\": \"structures  are still  analaysed  by  assuming thating  that  neither  the  bolt  nor  the  elements  being\"}, {\"0\": \"individual  elements  are  simply  supported  at  theirjoined exceed their shear,  bearing  or tension\"}, {\"0\": \"ends. Steel sections are classified as plastic, compact,capacities.  Where  HSFG  bolts  are  used,  the  slip\"}, {\"0\": \"semi-compact  or  slender  depending  on  how  theresistance  must  also  be  determined.  Welded  con-\"}, {\"0\": \"sections perform in bending. The design of flexuralnections  are  most  often  used  to  weld  end  plates\"}, {\"0\": \"members  generally  involves  considering  the  limitor  cleats  to  members,  a  task  which  is  normally\"}, {\"0\": \"states  of  bending,  shear,  web  bearing/buckling,performed  in  the  fabrication  yard  rather  than  on\"}, {\"0\": \"deflection and if the compression flange is not fullysite.\"}, {\"0\": \"236\"}], [], []]\n\n[FORMULAS]\n3 = 1; a = 0", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0257.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 258, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n237\nSummary\nQuestions\n1. A simply-supported beam spanning 8 m\nhas central point dead and imposed loads\nof 200 kN and 100 kN respectively.\nAssuming the beam is fully laterally\nrestrained select and check suitable\nUB sections in (a) S275 and (b) S460\nsteel.\n2. A simply-supported beam spanning 8 m\nhas uniformly distributed dead and\nimposed loads of 20 kN/m and 10 kN/m\nrespectively. Assuming the beam is fully\nlaterally restrained select and check suitable\nuniversal beam sections in (a) grade S275\nand (b) grade S460 steel.\n40 kN/m dead load\n12 kN imposed load\n+ 32 kN/m imposed load\n12 kN imposed load\n8000\n2000\nFig. 4.59\n3. For the fully laterally restrained beam\nshown in Fig. 4.59 select and check a\nsuitable UB section in grade S275 steel\nto satisfy shear, bending and deflection\ncriteria.\n4. If the above beam is laterally unrestrained,\nselect and check a suitable section in\ngrade S275 steel to additionally satisfy\nlateral torsional buckling, web bearing\nand buckling criteria. Assume that each\nsupport is 50 mm long and lateral\nrestraint conditions at supports are as\nfollows: –\nCompression flange laterally restrained.\nBeam fully restrained against torsion.\nBoth flanges free to rotate on plan.\nDestabilising load conditions.\n5. If two discrete lateral restraints, one at\nmid-span, and one at the cantilever tip,\nare used to stabilise the above beam,\nselect and check a suitable section in\ngrade S275 steel to satisfy all the criteria\nin question 4.\n6. Carry out designs for the beams shown in\nFig. 4.60.\n7. (a) List and discuss the merits of floor\nsystems used in steel framed structures.\n(b) A floor consists of a series of beams\n8.0 m span and 4.0 m apart,\nsupporting a reinforced concrete slab\n120 mm thick. The superimposed\nload is 4 kN/m2 and the weight of\nfinishes is 1.2 kN/m2.\n(i) Assuming the slab and support\nbeams are not connected, select\nand check a suitable UB section\nin grade S355 steel.\n(ii) Repeat the above design assuming\nthe floor is of composite\nconstruction. Comment on your\nresults. Assume the unit weight of\nreinforced concrete is 24 kN/m3.\n8. (a) List and discuss the factors that\ninfluence the load carrying capacity\nof steel columns.\n(b) A 254 × 254 × 132 universal column\nin grade S275 steel is required to\nsupport an ultimate axial compressive\nload of 1400 kN and a major axis\nmoment of 160 kN m applied at the\ntop of the element. Assuming the\ncolumn is 5 m long and effectively\npin ended about both axes, check the\nsuitability of the section.\n9. A 305 × 305 × 137 UC section extends\nthrough a height of 3.5 m.\n(a) Check that the section is suitable for\nplastic design using grade S275 and\ngrade S355 steel.\n(b) Calculate the squash load for grade\nS275 steel.\n(c) Calculate the full plastic moment of\nresistance for grade S275 steel about\nthe major axis.\n(d) Find the reduced plastic moment of\nresistance about the major axis when\nF = 800 kN using grade S275 steel.\n\n[TABLES]\n[[{\"0\": \"Questions\"}, {\"0\": \"1. A simply-supported beam spanning 8 m2. A simply-supported beam spanning 8 m\"}, {\"0\": \"has central point dead and imposed loadshas uniformly distributed dead and\"}, {\"0\": \"of 200 kN and 100 kN respectively.imposed loads of 20 kN/m and 10 kN/m\"}, {\"0\": \"Assuming the beam is fully laterallyrespectively. Assuming the beam is fully\"}, {\"0\": \"restrained select and check suitablelaterally restrained select and check suitable\"}, {\"0\": \"UB sections in (a) S275 and (b) S460universal beam sections in (a) grade S275\"}, {\"0\": \"steel.and (b) grade S460 steel.\"}, {\"0\": \"12 kN imposed load12 kN imposed load\"}, {\"0\": \"40 kN/m dead load+ 32 kN/m imposed load\"}, {\"0\": \"80002000\"}, {\"0\": \"Fig. 4.59\"}, {\"0\": \"3. For the fully laterally restrained beam(i)Assuming the slab and support\"}, {\"0\": \"shown in Fig. 4.59 select and check abeams are not connected, select\"}, {\"0\": \"suitable UB section in grade S275 steeland check a suitable UB section\"}, {\"0\": \"to satisfy shear, bending and deflectionin grade S355 steel.\"}, {\"0\": \"criteria.(ii) Repeat the above design assuming\"}, {\"0\": \"4.If the above beam is laterally unrestrained,the floor is of composite\"}, {\"0\": \"select and check a suitable section inconstruction. Comment on your\"}, {\"0\": \"grade S275 steel to additionally satisfyresults. Assume the unit weight of\"}, {\"0\": \"lateral torsional buckling, web bearingreinforced concrete is 24 kN/m3.\"}, {\"0\": \"8.(a) List and discuss the factors thatand buckling criteria. Assume that each\"}, {\"0\": \"support is 50 mm long and lateralinfluence the load carrying capacity\"}, {\"0\": \"restraint conditions at supports are asof steel columns.\"}, {\"0\": \"(b) A 254 × 254 × 132 universal columnfollows: –\"}, {\"0\": \"in grade S275 steel is required toCompression flange laterally restrained.\"}, {\"0\": \"support an ultimate axial compressiveBeam fully restrained against torsion.\"}, {\"0\": \"load of 1400 kN and a major axisBoth flanges free to rotate on plan.\"}, {\"0\": \"moment of 160 kN m applied at theDestabilising load conditions.\"}, {\"0\": \"top of the element. Assuming the\"}, {\"0\": \"column is 5 m long and effectively5.If two discrete lateral restraints, one at\"}, {\"0\": \"mid-span, and one at the cantilever tip,pin ended about both axes, check the\"}, {\"0\": \"are used to stabilise the above beam,suitability of the section.\"}, {\"0\": \"9. A 305 × 305 × 137 UC section extendsselect and check a suitable section in\"}, {\"0\": \"grade S275 steel to satisfy all the criteriathrough a height of 3.5 m.\"}, {\"0\": \"in question 4.(a) Check that the section is suitable for\"}, {\"0\": \"plastic design using grade S275 and6. Carry out designs for the beams shown in\"}, {\"0\": \"Fig. 4.60.grade S355 steel.\"}, {\"0\": \"7.(a) List and discuss the merits of floor(b) Calculate the squash load for grade\"}, {\"0\": \"S275 steel.systems used in steel framed structures.\"}, {\"0\": \"(b) A floor consists of a series of beams(c) Calculate the full plastic moment of\"}, {\"0\": \"8.0 m span and 4.0 m apart,resistance for grade S275 steel about\"}, {\"0\": \"the major axis.supporting a reinforced concrete slab\"}, {\"0\": \"120 mm thick. The superimposed(d) Find the reduced plastic moment of\"}, {\"0\": \"load is 4 kN/m2 and the weight ofresistance about the major axis when\"}, {\"0\": \"finishes is 1.2 kN/m2.F = 800 kN using grade S275 steel.\"}], [{\"0\": \"8000\", \"1\": \"2000\"}, {\"0\": \"Fig. 4.59\", \"1\": \"\"}, {\"0\": \"3. For the fully laterally restrained beam\", \"1\": \"(i)Assuming the slab and support\"}, {\"0\": \"shown in Fig. 4.59 select and check a\", \"1\": \"beams are not connected, select\"}, {\"0\": \"suitable UB section in grade S275 steel\", \"1\": \"and check a suitable UB section\"}, {\"0\": \"to satisfy shear, bending and deflection\", \"1\": \"in grade S355 steel.\"}, {\"0\": \"criteria.\", \"1\": \"(ii) Repeat the above design assuming\"}, {\"0\": \"4.If the above beam is laterally unrestrained,\", \"1\": \"the floor is of composite\"}, {\"0\": \"select and check a suitable section in\", \"1\": \"construction. Comment on your\"}, {\"0\": \"grade S275 steel to additionally satisfy\", \"1\": \"results. Assume the unit weight of\"}, {\"0\": \"lateral torsional buckling, web bearing\", \"1\": \"reinforced concrete is 24 kN/m3.\"}, {\"0\": \"and buckling criteria. Assume that each\", \"1\": \"8.(a) List and discuss the factors that\"}, {\"0\": \"support is 50 mm long and lateral\", \"1\": \"influence the load carrying capacity\"}, {\"0\": \"restraint conditions at supports are as\", \"1\": \"of steel columns.\"}, {\"0\": \"follows: –\", \"1\": \"(b) A 254 × 254 × 132 universal column\"}, {\"0\": \"Compression flange laterally restrained.\", \"1\": \"in grade S275 steel is required to\"}, {\"0\": \"Beam fully restrained against torsion.\", \"1\": \"support an ultimate axial compressive\"}, {\"0\": \"Both flanges free to rotate on plan.\", \"1\": \"load of 1400 kN and a major axis\"}, {\"0\": \"Destabilising load conditions.\", \"1\": \"moment of 160 kN m applied at the\"}, {\"0\": \"\", \"1\": \"top of the element. Assuming the\"}, {\"0\": \"5.If two discrete lateral restraints, one at\", \"1\": \"column is 5 m long and effectively\"}, {\"0\": \"mid-span, and one at the cantilever tip,\", \"1\": \"pin ended about both axes, check the\"}, {\"0\": \"are used to stabilise the above beam,\", \"1\": \"suitability of the section.\"}, {\"0\": \"select and check a suitable section in\", \"1\": \"9. A 305 × 305 × 137 UC section extends\"}, {\"0\": \"grade S275 steel to satisfy all the criteria\", \"1\": \"through a height of 3.5 m.\"}, {\"0\": \"in question 4.\", \"1\": \"(a) Check that the section is suitable for\"}, {\"0\": \"6. Carry out designs for the beams shown in\", \"1\": \"plastic design using grade S275 and\"}, {\"0\": \"Fig. 4.60.\", \"1\": \"grade S355 steel.\"}, {\"0\": \"7.(a) List and discuss the merits of floor\", \"1\": \"(b) Calculate the squash load for grade\"}, {\"0\": \"systems used in steel framed structures.\", \"1\": \"S275 steel.\"}, {\"0\": \"(b) A floor consists of a series of beams\", \"1\": \"(c) Calculate the full plastic moment of\"}, {\"0\": \"8.0 m span and 4.0 m apart,\", \"1\": \"resistance for grade S275 steel about\"}, {\"0\": \"supporting a reinforced concrete slab\", \"1\": \"the major axis.\"}, {\"0\": \"120 mm thick. The superimposed\", \"1\": \"(d) Find the reduced plastic moment of\"}, {\"0\": \"load is 4 kN/m2 and the weight of\", \"1\": \"resistance about the major axis when\"}, {\"0\": \"finishes is 1.2 kN/m2.\", \"1\": \"F = 800 kN using grade S275 steel.\"}], [], [], [{\"Questions\\n1. A simply-supported beam spanning 8 m 2. A simply-supported beam spanning 8 m\\nhas central point dead and imposed loads has uniformly distributed dead and\\nof 200 kN and 100 kN respectively. imposed loads of 20 kN/m and 10 kN/m\\nAssuming the beam is fully laterally respectively. Assuming the beam is fully\\nrestrained select and check suitable laterally restrained select and check suitable\\nUB sections in (a) S275 and (b) S460 universal beam sections in (a) grade S275\\nsteel. and (b) grade S460 steel.\\n12 kN imposed load 12 kN imposed load\\n40 kN/m dead load + 32 kN/m imposed load\\n8000 2000\\nFig. 4.59\\n3. For the fully laterally restrained beam (i) Assuming the slab and support\\nshown in Fig. 4.59 select and check a beams are not connected, select\\nsuitable UB section in grade S275 steel and check a suitable UB section\\nto satisfy shear, bending and deflection in grade S355 steel.\\ncriteria. (ii) Repeat the above design assuming\\n4. If the above beam is laterally unrestrained, the floor is of composite\\nselect and check a suitable section in construction. Comment on your\\ngrade S275 steel to additionally satisfy results. Assume the unit weight of\\nlateral torsional buckling, web bearing reinforced concrete is 24 kN/m3.\\nand buckling criteria. Assume that each 8. (a) List and discuss the factors that\\nsupport is 50 mm long and lateral influence the load carrying capacity\\nrestraint conditions at supports are as of steel columns.\\nfollows: – (b) A 254 × 254 × 132 universal column\\nin grade S275 steel is required to\\nCompression flange laterally restrained.\\nsupport an ultimate axial compressive\\nBeam fully restrained against torsion.\\nload of 1400 kN and a major axis\\nBoth flanges free to rotate on plan.\\nmoment of 160 kN m applied at the\\nDestabilising load conditions .\\ntop of the element. Assuming the\\n5. If two discrete lateral restraints, one at column is 5 m long and effectively\\nmid-span, and one at the cantilever tip, pin ended about both axes, check the\\nare used to stabilise the above beam, suitability of the section.\\nselect and check a suitable section in 9. A 305 × 305 × 137 UC section extends\\ngrade S275 steel to satisfy all the criteria through a height of 3.5 m.\\nin question 4. (a) Check that the section is suitable for\\n6. Carry out designs for the beams shown in plastic design using grade S275 and\\nFig. 4.60. grade S355 steel.\\n7. (a) List and discuss the merits of floor (b) Calculate the squash load for grade\\nsystems used in steel framed structures. S275 steel.\\n(b) A floor consists of a series of beams (c) Calculate the full plastic moment of\\n8.0 m span and 4.0 m apart, resistance for grade S275 steel about\\nsupporting a reinforced concrete slab the major axis.\\n120 mm thick. The superimposed (d) Find the reduced plastic moment of\\nload is 4 kN/m2 and the weight of resistance about the major axis when\\nfinishes is 1.2 kN/m2. F = 800 kN using grade S275 steel.\": \"\", \"None\": \"\"}]]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0258.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 259, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in structural steelwork to BS 5950\n238\n50 kN\nimposed load\n20 kN m–1\ndead load\n3 m\n50 kN\n50 kN\n50 kN\n50 kN\nimposed loads\n3 m\n30 kN\nimposed load\n30 kN\nimposed load\n10 kN m–1 dead load\n5 m\n2.5 m\n100 kN\nimposed load\n20 kN m–1\ndead load\n20 kN m–1\ndead load\n2 m\n4 m\n2 m\n100 kN\nimposed load\nFig. 4.60\n250 mm\n500 kN\n350 mm\n175 mm\n10 mm fillet welds\ns\ns\n12. Design a splice connection for a 686 ×\n254 × 140 UB section in grade S275 steel\nto cater for half bending strength and\nhalf the shear capacity of the section.\n13. (a) Explain with the aid of sketches the\nfollowing terms used in welded\nconnections:\n(i)\nfillet welds\n(ii) butt welds\n(iii) throat size.\n(b) A bracket made from a 406 × 178 ×\n60 universal beam is welded to a\nsteel column as shown below. The\nbracket is designed to support an\nultimate load of 500 kN. Show the\nproposed welding scheme for this\nconnection is adequate. Assume the\nsteel is of grade S275 and the\nelectrode strength is 42.\n(e) When Mx = 500 kN, check the\nlocal and overall capacity of the\ncolumn assuming the base is pinned.\n10. Select a suitable short column section in\ngrade S275 steel to support a factored\naxial concentric load of 1000 kN and\nfactored bending moments of 400 kN m\nabout the major axis, and 100 kN m\nabout the minor axis.\n11. Select a suitable column section in grade\nS275 steel to support a factored axial\nconcentric load of 1000 kN and factored\nbending moments of 400 kN m about\nthe major axis, and 100 kN m about the\nminor axis, both applied at each end.\nThe column is 10 m long and is fully\nfixed against rotation at top and bottom,\nand the floors it supports are braced\nagainst sway.\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}], [{\"0\": \"\", \"1\": \"\", \"2\": \"s\", \"3\": \"\", \"4\": \"\", \"5\": \"10 mm fillet welds\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"s\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}], [{\"0\": \"Design in structural steelwork to BS 595050 kN50 kN50 kN50 kN50 kNimposed loadimposed loads20 kN m–1dead load3 m3 m30 kN30 kNimposed loadimposed load10 kN m–1 dead load5 m2.5 m100 kN100 kNimposed loadimposed load20 kN m–120 kN m–1dead loaddead load2 m4 m2 mFig. 4.6012. Design a splice connection for a 686 ×(e) When Mx = 500 kN, check thelocal and overall capacity of the254 × 140 UB section in grade S275 steelcolumn assuming the base is pinned.to cater for half bending strength and10. Select a suitable short column section inhalf the shear capacity of the section.grade S275 steel to support a factored13.(a) Explain with the aid of sketches theaxial concentric load of 1000 kN andfollowing terms used in weldedfactored bending moments of 400 kN mconnections:about the major axis, and 100 kN m(i)fillet weldsabout the minor axis.(ii)butt welds11. Select a suitable column section in grade(iii)throat size.S275 steel to support a factored axial(b) A bracket made from a 406 × 178 ×concentric load of 1000 kN and factored60 universal beam is welded to abending moments of 400 kN m aboutsteel column as shown below. Thethe major axis, and 100 kN m about thebracket is designed to support anminor axis, both applied at each end.ultimate load of 500 kN. Show theThe column is 10 m long and is fullyproposed welding scheme for this fixed against rotation at top and bottom,connection is adequate. Assume theand the floors it supports are bracedsteel is of grade S275 and theagainst sway.electrode strength is 42.250 mm500 kN175 mm2389780415467193_C042389/3/09, 1:57 PM\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"s\", \"9\": \"\", \"10\": \"\", \"11\": \"10 mm fillet welds\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"350 mm\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"s\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\", \"12\": \"\"}], [], [], [{\"\": \"50 kN 50 kN 50 kN 50 kN 50 kN\\nimposed load imposed loads\\n20 kN m–1\\ndead load\\n3 m 3 m\\n30 kN 30 kN\\nimposed load imposed load\\n10 kN m–1 dead load\\n5 m 2.5 m\\n100 kN\\n100 kN\\nimposed load\\nimposed load\\n20 kN m–1 20 kN m–1\\ndead load dead load\\n2 m 4 m 2 m\\nFig. 4.60\\n(e) When M = 500 kN, check the 12. Design a splice connection for a 686 ×\\nx\\nlocal and overall capacity of the 254 × 140 UB section in grade S275 steel\\ncolumn assuming the base is pinned. to cater for half bending strength and\\n10. Select a suitable short column section in half the shear capacity of the section.\\ngrade S275 steel to support a factored 13. (a) Explain with the aid of sketches the\\naxial concentric load of 1000 kN and following terms used in welded\\nfactored bending moments of 400 kN m connections:\\nabout the major axis, and 100 kN m (i) fillet welds\\nabout the minor axis. (ii) butt welds\\n11. Select a suitable column section in grade (iii) throat size.\\nS275 steel to support a factored axial (b) A bracket made from a 406 × 178 ×\\nconcentric load of 1000 kN and factored 60 universal beam is welded to a\\nbending moments of 400 kN m about steel column as shown below. The\\nthe major axis, and 100 kN m about the bracket is designed to support an\\nminor axis, both applied at each end. ultimate load of 500 kN. Show the\\nThe column is 10 m long and is fully proposed welding scheme for this\\nfixed against rotation at top and bottom, connection is adequate. Assume the\\nand the floors it supports are braced steel is of grade S275 and the\\nagainst sway. electrode strength is 42.\\n250 mm\\n500 kN\\n175 mm\\ns\\n350 mm 10 mm fillet welds\\ns\"}]]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0259.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 260, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n239\nChapter 5\nDesign in\nunreinforced masonry\nto BS 5628\nconcrete due largely to the research and marketing\nwork sponsored in particular by the Brick Devel-\nopment Association. For instance, everybody now\nknows that ‘brick is beautiful’. Less well appreciated,\nFig. 5.1 Traditional application of masonry in construction: (a) brick bridge; (b) brick sewer; (c) brick retaining wall.\nThis chapter is concerned with the design of unreinforced\nmasonry walls to BS 5628: Part 1. The chapter describes\nthe composition and properties of the three main mate-\nrials used in masonry construction: bricks, blocks and\nmortars. Masonry is primarily used nowadays in the\nconstruction of load-bearing and non-load-bearing walls.\nThe primary aim of this chapter is to give guidance on\nthe design of single leaf and cavity walls, with and\nwithout stiffening piers, subject to either vertical or\nlateral loading.\n5.1 Introduction\nStructural masonry was traditionally very widely\nused in civil and structural works including tun-\nnels, bridges, retaining walls and sewerage systems\n(Fig. 5.1). However, the introduction of steel and\nconcrete with their superior strength and cost\ncharacteristics led to a sharp decline in the use of\nmasonry for these applications.\nOver the past two decades or so, masonry has\nrecaptured some of the market lost to steel and\n(a)\n(c)\n(b)\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"to BS 5628\"}, {\"0\": \"This chapter is concerned with the design of unreinforced\", \"1\": \"concrete due largely to the research and marketing\"}, {\"0\": \"masonry walls to BS 5628: Part 1. The chapter describes\", \"1\": \"work  sponsored  in  particular  by  the  Brick  Devel-\"}, {\"0\": \"the composition and properties of the three main mate-\", \"1\": \"opment Association. For instance, everybody now\"}, {\"0\": \"rials  used  in  masonry  construction:  bricks,  blocks  and\", \"1\": \"knows that ‘brick is beautiful’. Less well appreciated,\"}, {\"0\": \"mortars.  Masonry  is  primarily  used  nowadays  in  the\", \"1\": \"(b)\"}, {\"0\": \"construction of load-bearing and non-load-bearing walls.\", \"1\": \"\"}, {\"0\": \"The primary aim of this chapter is to give guidance on\", \"1\": \"\"}, {\"0\": \"the  design  of  single  leaf  and  cavity  walls,  with  and\", \"1\": \"\"}, {\"0\": \"without  stiffening  piers,  subject to  either  vertical  or\", \"1\": \"\"}, {\"0\": \"lateral loading.\", \"1\": \"\"}, {\"0\": \"5.1 Introduction\", \"1\": \"\"}, {\"0\": \"Structural  masonry  was  traditionally  very  widely\", \"1\": \"\"}, {\"0\": \"used  in  civil  and  structural  works  including  tun-\", \"1\": \"\"}, {\"0\": \"nels, bridges, retaining walls and sewerage systems\", \"1\": \"\"}, {\"0\": \"(Fig.  5.1).  However,  the  introduction  of  steel  and\", \"1\": \"\"}, {\"0\": \"concrete  with their superior strength  and  cost\", \"1\": \"\"}, {\"0\": \"characteristics  led  to  a  sharp  decline  in  the  use  of\", \"1\": \"\"}, {\"0\": \"masonry for these applications.\", \"1\": \"\"}, {\"0\": \"Over  the  past  two  decades  or  so,  masonry  has\", \"1\": \"\"}, {\"0\": \"recaptured  some  of  the  market  lost  to  steel  and\", \"1\": \"\"}, {\"0\": \"(a)\", \"1\": \"(c)\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0260.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 262, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n241\n5.2.1 BRICKS\nBricks are manufactured from a variety of materials\nsuch as clay, calcium silicate (lime and sand/flint),\nconcrete and natural stone. Of these, clay bricks\nare by far the most commonly used variety in the\nUK.\nClay bricks are manufactured by shaping suit-\nable clays to units of standard size, normally taken\nto be 215 × 102.5 × 65 mm (Fig. 5.5). Sand facings\nand face textures may then be applied to the ‘green’\nclay. Alternatively, the clay units may be perforated\nor frogged in order to reduce the self-weight of the\nunit. Thereafter, the clay units are fired in kilns to\na temperature in the range 900–1500 °C in order\nto produce a brick suitable for structural use. The\nfiring process significantly increases both the\nstrength and durability of the units.\nIn design it is normal to refer to the coordinating\nsize of bricks. This is usually taken to be 225 ×\n112.5 × 75 mm and is based on the actual or work\nFig. 5.3 Wall ties to BS EN 845-1: (a) butterfly tie; (b) double triangle tie; (c) vertical twist tie.\nFig. 5.6 Coordinating and work size of bricks.\nsize of the brick, i.e. 215 × 102.5 × 65 mm, plus an\nallowance of 10 mm for the mortar joint (Fig. 5.6).\nClay bricks are also manufactured in metric modu-\nlar format having a coordinating size of 200 × 100\n× 75 mm. Other cuboid and special shapes are also\navailable (BS 4729).\nFig. 5.4 Damp proof courses: (a) lead, copper, polythene,\nbitumen polymer, mastic asphalt; (b) two courses of bonded\nslate; (c) two courses of d.p.c. bricks (based on Table 2,\nBS 5628: Part 3).\nFig. 5.5 Types of bricks: (a) solid; (b) perforated;\n(c) frogged.\nMaterials\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}], [{\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}], [{\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}], [{\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}], [{\"0\": \"Fig. 5.6 Coordinating and work size of bricks.\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0262.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 263, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n242\nAccording to BS EN 771-1, clay bricks can\nprimarily be specified in terms of:\n•\ndensity\n•\ncompressive strength\n•\ndurability\n•\nactive soluble salt content\n•\nwater absorption\nClay bricks with a gross density of less than or\nequal to 1000 kg/mm3 are classified as LD (low\ndensity) units and those with a gross density exceed-\ning 1000 kg/m3 as HD (high density) units. Clay\nbricks available in the UK are generally HD type\nunits.\nThe compressive strength of bricks is a func-\ntion of the raw materials and the actual processes\nused to manufacture the units. Bricks are generally\navailable with compressive strengths ranging from\n5 N/mm2 to more than 150 N/mm2.\nBS EN 771-1 defines three durability categories\nfor clay bricks, namely F0, F1 and F2, which\nindicate their susceptibility to frost damage in\nsaturated or near saturated conditions (Table 5.1).\nFor example, external brickwork near ground level\nwith a high risk of saturation, poorly drained with\nfreezing, would typically be built using category F2\nbrick. On the other hand, internal walls could be\nmade using category F0 bricks. There are also three\ncategories of soluble salt content defined in the\nstandard (Table 5.2). A high soluble salt content\nincreases the risk of sulphate attack of the mortar\nand, possibly, of the bricks themselves, if there is a\nconsiderable amount of water movement through\nthe masonry. A more common problem associated\nwith soluble salts is that of efflorescence staining\nof brickwork. This is a white deposit caused by\nthe crystallisation of soluble salts in brickwork as a\nresult of wet masonry drying out. Efflorescence is\nnot structurally significant but can mar brickwork’s\nappearance. Magnesium sulphate may cause\ndamage to the units and it is for this reason the\nmagnesium content is specified separately.\nBrick manufacturers are also required to declare\nthe water absorption category (expressed as a\npercentage increase in weight) of the unit as this\ninfluences flexural strength (see section 5.6). The\nwater absorption categories for which flexural\nstrength data is available in the UK are: less than\n7 per cent, 7–12 per cent and > 12 per cent and\nare determined using the test procedure described\nin Annex C of BS EN 771-1.\nClay bricks are often referred to as commons,\nfacing, engineering and DPC, which reflects their\nusage. Common bricks are those suitable for gen-\neral construction work, with no special claim to\ngive an attractive appearance. Facing bricks on the\nother hand are specially made or selected to give\nan attractive appearance on the basis of colour and\ntexture. Engineering bricks tend to be high density\nand are designated class A and class B on the basis\nof strength, water absorption, frost resistance and\nthe maximum soluble salt content (Table 5.3). Clay\ndamp-proof course bricks (DPC 1 and DPC 2) are\nclassified in terms of their water absorption property\nonly.\nGuidance on the selection of clay bricks most\nappropriate for particular applications can be found\nin Table 12 of BS 5628: Part 3 (see below).\n5.2.2 BLOCKS\nBlocks are walling units but, unlike bricks, are\nnormally made from concrete. They are available\nin two basic types: autoclaved aerated concrete (now\nreferred to as aircrete) and aggregate concrete.\nThe aircrete blocks are made from a mixture of\nsand, pulverised fuel ash, cement and aluminium\npowder. The latter is used to generate hydrogen\nbubbles in the mix; none of the powder remains\nafter the reaction. The aggregate blocks have a com-\nposition similar to that of normal concrete, con-\nsisting chiefly of sand, coarse and fine aggregate\nand cement plus extenders. Aircrete blocks tend\nto have lower densities (typically 400–900 kg/m3)\nthan aggregate blocks (typically 1200–2400 kg/m3)\nwhich accounts for the former’s superior thermal\nproperties, lower unit weight and lower strengths.\nCommonly produced compressive strength of\nTable 5.2\nSoluble salt categories for clay bricks\n(Table 1, EN 771-1)\nCategory\nTotal % by mass not greater than\nNa+ + K+\nMg 2+\nS0\nNo requirements\nNo requirements\nS1\n0.17\n0.08\nS2\n0.06\n0.03\nTable 5.1\nDurability categories for clay bricks\nDurability category\nFrost resistance\nF0\nPassive exposure\nF1\nModerate exposure\nF2\nSevere exposure\n\n[TABLES]\n[[{\"0\": \"Design in unreinforced masonry to BS 5628\", \"1\": \"\"}, {\"0\": \"According to  BS  EN  771-1,  clay  bricks  can\", \"1\": \"the masonry. A more common problem associated\"}, {\"0\": \"primarily be specified in terms of:\", \"1\": \"with  soluble  salts  is  that  of  efflorescence  staining\"}, {\"0\": \"•density\", \"1\": \"of  brickwork.  This  is  a  white  deposit  caused  by\"}, {\"0\": \"•compressive strength\", \"1\": \"the crystallisation of soluble salts in brickwork as a\"}, {\"0\": \"•durability\", \"1\": \"result  of  wet  masonry  drying  out.  Efflorescence  is\"}, {\"0\": \"•active soluble salt content\", \"1\": \"not structurally significant but can mar brickwork’s\"}, {\"0\": \"•water absorption\", \"1\": \"appearance.  Magnesium sulphate  may cause\"}, {\"0\": \"\", \"1\": \"damage  to  the  units  and  it  is  for  this  reason  the\"}, {\"0\": \"Clay  bricks  with  a  gross  density  of  less  than  or\", \"1\": \"magnesium content is specified separately.\"}, {\"0\": \"equal  to  1000  kg/mm3  are  classified  as  LD  (low\", \"1\": \"Brick manufacturers are also required to declare\"}, {\"0\": \"density) units and those with a gross density exceed-\", \"1\": \"the  water  absorption  category (expressed  as  a\"}, {\"0\": \"ing  1000  kg/m3  as  HD  (high  density)  units.  Clay\", \"1\": \"percentage  increase  in  weight)  of  the  unit  as  this\"}, {\"0\": \"bricks  available  in  the  UK  are  generally  HD  type\", \"1\": \"influences  flexural  strength  (see  section  5.6).  The\"}, {\"0\": \"units.\", \"1\": \"water absorption categories for  which  flexural\"}, {\"0\": \"The  compressive  strength  of  bricks  is  a  func-\", \"1\": \"strength  data  is  available  in  the  UK  are:  less  than\"}, {\"0\": \"tion  of  the  raw  materials  and  the  actual  processes\", \"1\": \"7  per  cent,  7–12  per  cent  and  >  12  per  cent  and\"}, {\"0\": \"used to manufacture the units. Bricks are generally\", \"1\": \"are determined using the test procedure described\"}, {\"0\": \"available  with  compressive  strengths  ranging  from\", \"1\": \"in Annex C of BS EN 771-1.\"}, {\"0\": \"5 N/mm2 to more than 150 N/mm2.\", \"1\": \"Clay  bricks  are  often  referred  to  as  commons,\"}, {\"0\": \"BS EN 771-1 defines three durability categories\", \"1\": \"facing,  engineering  and  DPC,  which  reflects  their\"}, {\"0\": \"for  clay  bricks,  namely  F0,  F1  and  F2,  which\", \"1\": \"usage. Common bricks are those suitable for gen-\"}, {\"0\": \"indicate their susceptibility to frost  damage in\", \"1\": \"eral  construction  work,  with  no  special  claim  to\"}, {\"0\": \"saturated or near saturated conditions (Table 5.1).\", \"1\": \"give an attractive appearance. Facing bricks on the\"}, {\"0\": \"For example, external brickwork near ground level\", \"1\": \"other  hand  are  specially  made  or  selected  to  give\"}, {\"0\": \"with a high risk of saturation, poorly drained with\", \"1\": \"an attractive appearance on the basis of colour and\"}, {\"0\": \"freezing, would typically be built using category F2\", \"1\": \"texture. Engineering bricks tend to be high density\"}, {\"0\": \"brick.  On  the  other  hand,  internal  walls  could  be\", \"1\": \"and are designated class A and class B on the basis\"}, {\"0\": \"made using category F0 bricks. There are also three\", \"1\": \"of  strength,  water  absorption,  frost  resistance  and\"}, {\"0\": \"categories  of  soluble  salt  content  defined  in  the\", \"1\": \"the maximum soluble salt content (Table 5.3). Clay\"}, {\"0\": \"standard  (Table  5.2).  A  high  soluble  salt  content\", \"1\": \"damp-proof course bricks (DPC 1 and DPC 2) are\"}, {\"0\": \"increases  the  risk  of  sulphate  attack  of  the  mortar\", \"1\": \"classified in terms of their water absorption property\"}, {\"0\": \"and, possibly, of the bricks themselves, if there is a\", \"1\": \"only.\"}, {\"0\": \"considerable  amount  of  water  movement  through\", \"1\": \"Guidance  on  the  selection  of  clay  bricks  most\"}, {\"0\": \"\", \"1\": \"appropriate for particular applications can be found\"}, {\"0\": \"Table 5.1Durability categories for clay bricks\", \"1\": \"in Table 12 of BS 5628: Part 3 (see below).\"}, {\"0\": \"Durability categoryFrost resistance\", \"1\": \"5.2.2 BLOCKS\"}, {\"0\": \"\", \"1\": \"Blocks  are  walling  units  but,  unlike  bricks,  are\"}, {\"0\": \"F0Passive exposure\", \"1\": \"normally  made  from  concrete.  They  are  available\"}, {\"0\": \"F1Moderate exposure\", \"1\": \"in two basic types: autoclaved aerated concrete (now\"}, {\"0\": \"F2Severe exposure\", \"1\": \"referred to  as  aircrete)  and  aggregate  concrete.\"}, {\"0\": \"\", \"1\": \"The  aircrete  blocks  are  made  from  a  mixture  of\"}, {\"0\": \"\", \"1\": \"sand,  pulverised  fuel  ash,  cement  and  aluminium\"}, {\"0\": \"Table 5.2Soluble salt categories for clay bricks\", \"1\": \"powder.  The  latter  is  used  to  generate  hydrogen\"}, {\"0\": \"(Table 1, EN 771-1)\", \"1\": \"bubbles  in  the  mix;  none  of  the  powder  remains\"}, {\"0\": \"\", \"1\": \"after the reaction. The aggregate blocks have a com-\"}, {\"0\": \"CategoryTotal % by mass not greater than\", \"1\": \"position  similar  to  that  of  normal  concrete,  con-\"}, {\"0\": \"\", \"1\": \"sisting  chiefly  of  sand,  coarse  and  fine  aggregate\"}, {\"0\": \"Na+ + K +Mg 2+\", \"1\": \"and  cement  plus  extenders.  Aircrete  blocks  tend\"}, {\"0\": \"\", \"1\": \"to  have  lower  densities  (typically  400–900  kg/m3)\"}, {\"0\": \"S0No requirementsNo requirements\", \"1\": \"than aggregate blocks (typically 1200–2400 kg/m3)\"}, {\"0\": \"S10.170.08\", \"1\": \"which  accounts  for  the  former’s  superior  thermal\"}, {\"0\": \"S20.060.03\", \"1\": \"properties,  lower  unit  weight  and  lower  strengths.\"}, {\"0\": \"\", \"1\": \"Commonly produced compressive strength of\"}, {\"0\": \"242\", \"1\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0263.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 264, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n243\nWeb\nShell\nTable 5.3\nClassification of clay engineering and DPC bricks (based on Table NA.6, BS EN 771-1)\nType\nDeclared average\nAverage absorption\nFreeze/thaw\nSoluble\ncompressive strength\n(% by weight) not\nresistance\nsulphate\nnot less than (N/mm2)\ngreater than\nEngineering A\n125\n4.5\nF2\nS2\nEngineering B\n75\n7.0\nF2\nS2\nDamp-proof course 1\n–\n4.5\n–\n–\nDamp-proof course 2\n–\n7.0\n–\n–\nMaterials\nTable 5.5\nCompressive strength of concrete\nblocks (BS EN 771-3)\nCompressive strengths (N/mm2)\n2.9\n3.6\n5.2\n7.3\n10.4\n17.5\n22.5\n30.0\n40.0\naircrete blocks are 2.9, 3.6, 4.2, 7.3 and 8.7\nN/mm2. Generally, aircrete blocks are more expen-\nsive than aggregate blocks.\nBlocks are manufactured in three basic forms:\nsolid, cellular and hollow (Fig. 5.7). Solid blocks\nhave no formed holes or cavities other than those\ninherent in the material. Cellular blocks have one\nor more formed voids or cavities which do not pass\nthrough the block. Hollow blocks are similar to\ncellular blocks except that the voids or cavities pass\nthrough the block. As discussed in section 5.5.2.1,\nthe percentage of formed voids in blocks (and\nformed voids or frogs in bricks) influences the char-\nacteristic compressive strength of masonry.\nFig. 5.7 Concrete blocks: (a) solid; (b) cellular;\n(c) hollow.\nFor structural design, the two most important\nproperties of blocks are their size and compressive\nstrength. Tables 5.4 and 5.5 give the most com-\nmonly available sizes and compressive strengths of\nconcrete blocks in the UK. The most frequently\nused block has a work face of 440 × 215 mm,\nwidth 100 mm and compressive strength 3.6 N/mm2;\n2.9 N/mm2 is a popular strength for aircrete blocks,\nand 7.3 N/mm2 for aggregate concrete blocks as\nit can be used below ground. Guidance on the\nselection and specification of concrete blocks in\nmasonry construction can be found in BS 5628:\nPart 3 and BS EN 771-3 respectively.\nTable 5.4\nWork sizes of concrete blocks (Table NA.1,\nBS EN 771-3)\nLength\nHeight\nWidth (mm)\n(mm)\n(mm)\n75\n90\n100\n140\n150\n190\n200\n215\n225\n390\n190\n–\nx\nx\nx\n–\nx\nx\n–\n–\n440\n215\nx\nx\nx\nx\nx\nx\nx\nx\nx\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0264.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 265, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n244\nTable 5.7\nDesirable minimum quality of brick, blocks and mortar for durability (based on Table 12,\nBS 5628: Part 3)\nLocation or type of wall\nClay bricks\nConcrete blocks\nMortar\ndesignations\nNF a\nFH a\nInternal non-load-bearing walls\nNFa (F0)b\nAll types, t ≥ 75 mm\n(iv)\n(iii)\nFHa (F1)b\nInternal load-bearing walls, inner leaf of\nNFa (F0)b\nAll types, t ≥ 90 mm\n(iv)\n(iii)\ncavity walls\nFHa (F1)b\nSd\nExternal walls; outer leaf of cavity walls\nADc (F1)b\nAll types, t ≥ 90 mm\n(iv)e\n(iii)f\nBDc (F2)b\nSd\n(iii)g\n(iii)g\nExternal freestanding walls (with coping)\nF2b\nSd\n(iii)\n(iii)\nEarth retaining wall (back filled with\nF2b\nSd\n(ii)g,h\n(ii)g,h\nfree draining material)\nNotes:\naNF, no risk of frost during construction; FH, frost hazard a possibility during construction\nbF0, passive exposure; F1, moderate exposure; F2, severe exposure\ncAD, above damp proof course; BD, below damp proof course\ndBlocks should comply with one of the following: net density ≥ 1500 kgm−3 or be made with dense aggregate or have a\ncompressive strength ≥ 7.3 Nmm−2\neFor clay brickwork, mortar designation not less that (iii)\nfIf brickwork is to be rendered the use of plasticised mortars is desirable\ngWhere sulphates are present in the soil or ground water, use sulphate resisting Portland cement\nhFor clay bricks, mortar designation (i) should be used\nTable 5.6\nTypes of mortars (Table 1, BS 5628)\nMortar\nCompressive\nPrescribed mortars (proportion of materials by volume)\nCompressive\ndesignation\nstrength\nstrength at\n class\nCement-lime-\nCement-sand\nMasonry\nMasonry\n28 days\nsand with or\nwith or\ncement1-sand\ncement2-sand\n(N/mm2)\nwithout air\nwithout air\nentrainment\nentrainment\nIncreasing\n(i)\nM12\n1:0 to 1/4:3\n–\n–\n–\n12\nability to\n(ii)\nM6\n1:1/2:4 to 41/2\n1:3 to 4\n1:21/2 to 31/2\n1:3\n6\naccommodate\n(iii)\nM4\n1:1:5 to 6\n1:5 to 6\n1:4 to 5\n1:31/2 to 4\n4\nmovement,\n(iv)\nM2\n1:2:8 to 9\n1:7 to 8\n1:51/2 to 61/2\n1:41/2\n2\ne.g. due to\nsettlement,\ntemperature\nand moisture\nchanges\nNotes:\n1Masonry cement with organic filler other than lime\n2Masonry cement with lime\n\n[TABLES]\n[[{\"0\": \"Design in unreinforced masonry to BS 5628\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"Table 5.6\", \"1\": \"Types of mortars (Table 1, BS 5628)\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"\", \"1\": \"Mortar\", \"2\": \"Compressive\", \"3\": \"\", \"4\": \"Prescribed mortars (proportion of materials by volume)\", \"5\": \"\", \"6\": \"\", \"7\": \"Compressive\"}, {\"0\": \"\", \"1\": \"designation\", \"2\": \"strength\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"strength at\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"class\", \"3\": \"Cement-lime-\", \"4\": \"Cement-sand\", \"5\": \"Masonry\", \"6\": \"Masonry\", \"7\": \"28 days\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"sand with or\", \"4\": \"with or\", \"5\": \"cement1-sand\", \"6\": \"cement2-sand\", \"7\": \"(N/mm 2)\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"without air\", \"4\": \"without air\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"entrainment\", \"4\": \"entrainment\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"Increasing\", \"1\": \"(i)\", \"2\": \"M12\", \"3\": \"1:0 to 1/4:3\", \"4\": \"–\", \"5\": \"–\", \"6\": \"–\", \"7\": \"12\"}, {\"0\": \"ability to\", \"1\": \"(ii)\", \"2\": \"M6\", \"3\": \"1:1/2:4 to 41/2\", \"4\": \"1:3 to 4\", \"5\": \"1:21/2 to 31/2\", \"6\": \"1:3\", \"7\": \"6\"}, {\"0\": \"accommodate\", \"1\": \"(iii)\", \"2\": \"M4\", \"3\": \"1:1:5 to 6\", \"4\": \"1:5 to 6\", \"5\": \"1:4 to 5\", \"6\": \"1:31/2 to 4\", \"7\": \"4\"}, {\"0\": \"movement,\", \"1\": \"(iv)\", \"2\": \"M2\", \"3\": \"1:2:8 to 9\", \"4\": \"1:7 to 8\", \"5\": \"1:51/2 to 61/2\", \"6\": \"1:41/2\", \"7\": \"2\"}, {\"0\": \"e.g. due to\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"settlement,\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"temperature\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"and moisture\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}, {\"0\": \"changes\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\"}], [{\"0\": \"Table 5.7\", \"1\": \"Desirable minimum quality of brick, blocks and mortar for durability (based on Table 12,\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"BS 5628: Part 3)\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"Location or type of wall\", \"1\": \"Clay bricks\", \"2\": \"Concrete blocks\", \"3\": \"\", \"4\": \"Mortar\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"designations\", \"5\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"NF a\", \"4\": \"\", \"5\": \"FH a\"}, {\"0\": \"Internal non-load-bearing walls\", \"1\": \"NFa (F0)b\", \"2\": \"All types, t ≥ 75 mm\", \"3\": \"(iv)\", \"4\": \"\", \"5\": \"(iii)\"}, {\"0\": \"\", \"1\": \"FHa (F1)b\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"Internal load-bearing walls, inner leaf of\", \"1\": \"NFa (F0)b\", \"2\": \"All types, t ≥ 90 mm\", \"3\": \"(iv)\", \"4\": \"\", \"5\": \"(iii)\"}, {\"0\": \"cavity walls\", \"1\": \"FHa (F1)b\", \"2\": \"Sd\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}, {\"0\": \"External walls; outer leaf of cavity walls\", \"1\": \"ADc (F1)b\", \"2\": \"All types, t ≥ 90 mm\", \"3\": \"(iv)e\", \"4\": \"\", \"5\": \"(iii)f\"}, {\"0\": \"\", \"1\": \"BDc (F2)b\", \"2\": \"Sd\", \"3\": \"(iii)g\", \"4\": \"\", \"5\": \"(iii)g\"}, {\"0\": \"External freestanding walls (with coping)\", \"1\": \"F2b\", \"2\": \"Sd\", \"3\": \"(iii)\", \"4\": \"\", \"5\": \"(iii)\"}, {\"0\": \"Earth retaining wall (back filled with\", \"1\": \"F2b\", \"2\": \"Sd\", \"3\": \"(ii)g,h\", \"4\": \"\", \"5\": \"(ii)g,h\"}, {\"0\": \"free draining material)\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0265.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 266, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n245\nSymbols\nFor most forms of masonry construction a 1:1:6\ncement-lime-sand mortar is suitable. A simpler\noption may be to specify a masonry cement which\nconsists of a mixture of approximately 75 per cent\nOPC, an integral air entraining agent and fine\ninorganic fillers, e.g. calcium carbonate, or lime.\nSuch mixes will have similar properties to those\ndisplayed by cement-lime-sand plasticised mortars.\nBy varying the proportions of the constituents\nreferred to above, mortars of differing compressive\nand bond strength, plasticity and frost resistant\nproperties can be produced. Table 5.6 shows the\ncomposition of recommended types of mortars for\nmasonry construction. Table 5.7, which is based on\nTable 12 of BS 5628: Part 3, gives guidance on the\nselection of masonry units and mortars for use in\ndifferent applications.\n5.3 Masonry design\nThe foregoing has summarised some of the more\nimportant properties of the component materials\nwhich are used in masonry construction. As noted\nat the beginning of this chapter, masonry construc-\ntion is mostly used nowadays in the construction\nof load-bearing and panel walls. Load-bearing walls\nprimarily resist vertical loading whereas panel walls\nprimarily resist lateral loading. Figure 5.8 shows\nsome commonly used wall types.\nThe remainder of this chapter considers the\ndesign of (1) load-bearing walls, with and without\nstiffening piers, resisting vertical compression load-\ning (section 5.5) and (2) panel walls resisting lateral\nloading (section 5.6).\n5.4 Symbols\nFor the purposes of this chapter, the following sym-\nbols have been used. These have largely been taken\nfrom BS 5628.\nGEOMETRIC PROPERTIES:\nt\nactual thickness of wall or leaf\nh\nheight of panel between restraints\nL\nlength of wall between restraints\nA\ncross-sectional area of loaded wall\nZ\nsectional modulus\ntef\neffective thickness of wall\nhef\neffective height of wall\nK\neffective thickness coefficient\nex\neccentricity of loading at top of wall\nSR\nslenderness ratio\nβ\ncapacity reduction factor\n5.2.3 MORTARS\nThe primary function of the mortar is to bind to-\ngether the individual brick or block units, thereby\nallowing allow the transfer of compression, shear\nand tensile stresses between adjacent units, as well\nas provide an effective seal between masonry units\nagainst rain penetration. However, there are several\nother properties which the mortar must possess for\nease of construction and maintenance. For instance,\nthe mortar should be easy to spread and remain\nplastic for a sufficient length of time in order that\nthe units can be accurately positioned before setting\noccurs. On the other hand, the setting time should\nnot be too excessive otherwise the mortar may be\nsqueezed out as successive courses of units are laid.\nThe mortar should be able to resist water uptake\nby the absorbent bricks/blocks, e.g. by incorporating\na water-retaining admixture and/or use of a mortar\ntype that includes lime, otherwise hydration and\nhence full development of the mortar strength may\nbe prevented. The mortar must also be durable. For\nexample, if masonry remains wet for extended periods\nof time, the mortar may be susceptible to sulphate\nattack due to the presence of sulphate in clay\nmasonry units, the groundwater or the soil. Masonry\nmortar is also susceptible to freeze/thaw attack,\nparticularly when newly laid, which can adversely\naffect bond strength. It should be remembered too\nthat the appearance of mortar is also important and\nthat it should be in harmony with the masonry unit.\nIn its most basic form, mortar simply consists of a\nmixture of sand and ordinary Portland cement\n(OPC). However, such a mix is generally unsuitable\nfor use in masonry (other than perhaps in founda-\ntions and below damp-proof courses) since it will\ntend to be too strong in comparison with the strength\nof the bricks/blocks. It is generally desirable to pro-\nvide the lowest grade of mortar possible, taking into\naccount the strength and durability requirements of\nthe finished works. This is to ensure that any crack-\ning which occurs in the masonry due to settlement\nof the foundations, thermal/moisture movements,\netc. will occur in the mortar rather than the masonry\nunits themselves. Cracks in the mortar tend to be\nsmaller because the mortar is more flexible than the\nmasonry units and, hence, are easier to repair.\nIn order to produce a more practicable mix, it\nis normal to add lime to cement-sand mortar. This\nhas the effect of reducing the strength of the mix,\nbut at the same time increasing its workability and\nbonding properties. However, the mortar becomes\nmore susceptible to frost attack in saturated, or\nnear saturated, conditions but this can be offset\nby adding an air-entraining (plasticising) agent.\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"Symbols\"}, {\"0\": \"5.2.3 MORTARS\", \"1\": \"For  most  forms  of  masonry  construction  a  1:1:6\"}, {\"0\": \"The  primary  function  of  the  mortar  is  to  bind  to-\", \"1\": \"cement-lime-sand  mortar is  suitable.  A  simpler\"}, {\"0\": \"gether  the  individual  brick  or  block  units,  thereby\", \"1\": \"option may be to specify a masonry cement which\"}, {\"0\": \"allowing  allow  the  transfer  of  compression,  shear\", \"1\": \"consists of a mixture of approximately 75 per cent\"}, {\"0\": \"and tensile stresses between adjacent units, as well\", \"1\": \"OPC,  an integral  air  entraining  agent  and  fine\"}, {\"0\": \"as provide an effective seal between masonry units\", \"1\": \"inorganic  fillers,  e.g.  calcium  carbonate,  or  lime.\"}, {\"0\": \"against rain penetration. However, there are several\", \"1\": \"Such  mixes  will  have  similar  properties  to  those\"}, {\"0\": \"other properties which the mortar must possess for\", \"1\": \"displayed by cement-lime-sand plasticised mortars.\"}, {\"0\": \"ease of construction and maintenance. For instance,\", \"1\": \"By  varying  the  proportions  of  the  constituents\"}, {\"0\": \"the  mortar  should  be  easy  to  spread  and  remain\", \"1\": \"referred to above, mortars of differing compressive\"}, {\"0\": \"plastic for a sufficient length of time in order that\", \"1\": \"and  bond  strength,  plasticity  and  frost  resistant\"}, {\"0\": \"the units can be accurately positioned before setting\", \"1\": \"properties  can  be  produced.  Table  5.6  shows  the\"}, {\"0\": \"occurs. On the other hand, the setting time should\", \"1\": \"composition of recommended types of mortars for\"}, {\"0\": \"not  be  too  excessive  otherwise  the  mortar  may  be\", \"1\": \"masonry construction. Table 5.7, which is based on\"}, {\"0\": \"squeezed out as successive courses of units are laid.\", \"1\": \"Table 12 of BS 5628: Part 3, gives guidance on the\"}, {\"0\": \"The  mortar  should  be  able  to  resist  water  uptake\", \"1\": \"selection  of  masonry  units  and  mortars  for  use  in\"}, {\"0\": \"by the absorbent bricks/blocks, e.g. by incorporating\", \"1\": \"different applications.\"}, {\"0\": \"a water-retaining admixture and/or use of a mortar\", \"1\": \"\"}, {\"0\": \"type  that  includes  lime,  otherwise  hydration  and\", \"1\": \"\"}, {\"0\": \"hence full development of the mortar strength may\", \"1\": \"5.3 Masonry design\"}, {\"0\": \"be prevented. The mortar must also be durable. For\", \"1\": \"The  foregoing  has  summarised  some  of  the  more\"}, {\"0\": \"example, if masonry remains wet for extended periods\", \"1\": \"important  properties  of  the  component  materials\"}, {\"0\": \"of time, the mortar may be susceptible to sulphate\", \"1\": \"which are used in masonry construction. As noted\"}, {\"0\": \"attack  due to the  presence  of  sulphate in  clay\", \"1\": \"at the beginning of this chapter, masonry construc-\"}, {\"0\": \"masonry units, the groundwater or the soil. Masonry\", \"1\": \"tion  is  mostly  used  nowadays  in  the  construction\"}, {\"0\": \"mortar is  also  susceptible  to  freeze/thaw  attack,\", \"1\": \"of load-bearing and panel walls. Load-bearing walls\"}, {\"0\": \"particularly  when  newly  laid,  which  can  adversely\", \"1\": \"primarily resist vertical loading whereas panel walls\"}, {\"0\": \"affect bond strength. It should be remembered too\", \"1\": \"primarily  resist  lateral  loading.  Figure  5.8  shows\"}, {\"0\": \"that the appearance of mortar is also important and\", \"1\": \"some commonly used wall types.\"}, {\"0\": \"that it should be in harmony with the masonry unit.\", \"1\": \"The  remainder  of this  chapter  considers the\"}, {\"0\": \"In its most basic form, mortar simply consists of a\", \"1\": \"design of (1) load-bearing walls, with and without\"}, {\"0\": \"mixture  of  sand  and  ordinary  Portland  cement\", \"1\": \"stiffening piers, resisting vertical compression load-\"}, {\"0\": \"(OPC). However, such a mix is generally unsuitable\", \"1\": \"ing (section 5.5) and (2) panel walls resisting lateral\"}, {\"0\": \"for use in masonry (other than perhaps in founda-\", \"1\": \"loading (section 5.6).\"}, {\"0\": \"tions  and  below  damp-proof  courses)  since  it  will\", \"1\": \"\"}, {\"0\": \"tend to be too strong in comparison with the strength\", \"1\": \"\"}, {\"0\": \"of the bricks/blocks. It is generally desirable to pro-\", \"1\": \"5.4 Symbols\"}, {\"0\": \"vide the lowest grade of mortar possible, taking into\", \"1\": \"For the purposes of this chapter, the following sym-\"}, {\"0\": \"account the strength and durability requirements of\", \"1\": \"bols have been used. These have largely been taken\"}, {\"0\": \"the finished works. This is to ensure that any crack-\", \"1\": \"from BS 5628.\"}, {\"0\": \"ing which occurs in the masonry due to settlement\", \"1\": \"\"}, {\"0\": \"of  the  foundations,  thermal/moisture  movements,\", \"1\": \"GEOMETRIC PROPERTIES:\"}, {\"0\": \"etc. will occur in the mortar rather than the masonry\", \"1\": \"\"}, {\"0\": \"units  themselves.  Cracks  in  the  mortar  tend  to  be\", \"1\": \"tactual thickness of wall or leaf\"}, {\"0\": \"smaller because the mortar is more flexible than the\", \"1\": \"hheight of panel between restraints\"}, {\"0\": \"masonry units and, hence, are easier to repair.\", \"1\": \"Llength of wall between restraints\"}, {\"0\": \"In  order  to  produce  a  more  practicable  mix,  it\", \"1\": \"Across-sectional area of loaded wall\"}, {\"0\": \"is normal to add lime to cement-sand mortar. This\", \"1\": \"Zsectional modulus\"}, {\"0\": \"has the effect of reducing the strength of the mix,\", \"1\": \"effective thickness of walltef\"}, {\"0\": \"but at the same time increasing its workability and\", \"1\": \"effective height of wallhef\"}, {\"0\": \"bonding properties. However, the mortar becomes\", \"1\": \"Keffective thickness coefficient\"}, {\"0\": \"more  susceptible  to  frost  attack  in  saturated,  or\", \"1\": \"eccentricity of loading at top of wallex\"}, {\"0\": \"near  saturated,  conditions  but  this  can  be  offset\", \"1\": \"SRslenderness ratioβ\"}, {\"0\": \"by  adding  an  air-entraining  (plasticising)  agent.\", \"1\": \"capacity reduction factor\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0266.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 267, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n246\nCOMPRESSION:\nGk\ncharacteristic dead load\nQk\ncharacteristic imposed load\nWk\ncharacteristic wind load\nγf\npartial safety factor for load\nγm\npartial safety factor for materials\nfk\ncharacteristic compressive strength of\nmasonry\nN\nultimate design vertical load\nNR\nultimate design vertical load resistance of\nwall\nFLEXURE:\nfkx par\ncharacteristic flexural strength of masonry\nwith plane of failure parallel to bed joint\nfkx perp\ncharacteristic flexural strength of masonry\nwith plane of failure perpendicular to bed\njoint\nα\nbending moment coefficient\nµ\northogonal ratio\nM\nultimate design moment\nMR\ndesign moment of resistance\nMpar\ndesign moment with plane of failure\nparallel to bed joint\nMperp\ndesign moment with plane of failure\nperpendicular to bed joint\nMk par\ndesign moment of resistance with plane\nof failure parallel to bed joint\nMk perp\ndesign moment of resistance with plane\nof failure perpendicular to bed joint\n5.5 Design of vertically loaded\nmasonry walls\nIn common with most modern codes of practice\ndealing with structural design, BS 5628: Code of\nPractice for Use of Masonry is based on the limit\nFig. 5.8 Masonry walls.\nThe ultimate design load is a function of the actual\nloads bearing down on the wall. The design load\nresistance is related to the design strength of the\nmasonry wall. The following sub-sections discuss\nthe procedures for estimating the:\n1. ultimate design load,\n2. design strength of masonry walls and\n3. design load resistance of masonry walls.\n5.5.1 ULTIMATE DESIGN LOADS, N\nAs discussed in section 2.3, the loads acting on\na structure can principally be divided into three\nbasic types, namely dead loads, imposed (or live)\nloads and wind loads. Generally, the ultimate design\nload is obtained by multiplying the characteristic\n(dead/imposed/wind) loads (Fk) by the appropriate\npartial safety factor for loads (γf)\nN = γfFk\n(5.2)\nstate philosophy (Chapter 1). This code states that\nthe primary aim of design is to ensure an adequate\nmargin of safety against the ultimate limit state\nbeing reached. In the case of vertically loaded walls\nthis is achieved by ensuring that the ultimate\ndesign load (N) does not exceed the design load\nresistance of the wall (NR):\nN ≤ NR\n(5.1)\n\n[TABLES]\n[[{\"0\": \"Design in unreinforced masonry to BS 5628\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}], [{\"0\": \"\"}, {\"0\": \"\"}, {\"0\": \"\"}, {\"0\": \"\"}], [{\"0\": \"\"}, {\"0\": \"\"}, {\"0\": \"\"}, {\"0\": \"\"}], [], []]\n\n[FORMULAS]\nN = γfFk", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0267.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 268, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n247\nDesign of vertically loaded masonry walls\n5.5.1.1 Characteristic loads (clause 17,\nBS 5628)\nThe characteristic values of dead loads (Gk) and\nimposed loads (Qk) are obtained from the following:\n(i) BS 648: Schedule of Weights for Building Materials;\n(ii) BS 6399: Design Loadings for Buildings, Part 1:\nCode of Practice for Dead and Imposed Loads, Part 3:\nCode of Practice for Imposed Roof Loads. The charac-\nteristic wind load (Wk) is calculated in accordance\nwith BS 6399: Part 2: Wind loads.\n5.5.1.2 Partial safety factors for loads (γf)\n(clause 18, BS 5628)\nAs discussed in section 2.3.2, the applied loads\nmay be greater than anticipated for a number of\nreasons. Therefore, it is normal practice to factor\nup the characteristic loads. Table 5.8 shows the\npartial safety factors on loading for various load\ncombinations. Thus, with structures subject to only\ndead and imposed loads the partial safety factors\nfor the ultimate limit state are usually taken to be\n1.4 and 1.6 respectively. The ultimate design load\nfor this load combination is given by\nN = 1.4Gk + 1.6Qk\n(5.3)\nIn assessing the effect of dead, imposed and wind\nload for the ultimate limit state, the partial safety\nfactor is generally taken to be 1.2 for all the load\ntypes. Hence\nN = 1.2(Gk + Qk + Wk)\n(5.4)\n5.5.2 DESIGN COMPRESSIVE STRENGTH\nThe design compressive strength of masonry is given by\nDesign compressive strength = \n    \nβ\nγ\nfk\nm\n(5.5)\nwhere\nfk\ncharacteristic compressive strength of masonry\nγm\npartial safety factor for materials subject to\ncompression\nβ\ncapacity reduction factor\nEach of these factors is discussed in the following\nsections.\n5.5.2.1 Characteristic compressive strengths of\nmasonry, fk (clause 19, BS 5628)\nThe basic characteristic compressive strengths of\nnormally bonded masonry constructed under lab-\noratory conditions and tested at an age of 28 days\nare given in Table 5.9. As will be noted from the\ntable, the compressive strength is a function of\nseveral factors including the type and size of\nmasonry unit, percentage of formed voids or frogs,\ncompressive strength of the unit and designation/\nstrength class of the mortar used. The following\ndiscusses how the characteristic strength of ma-\nsonry constructed from (a) bricks and (b) concrete\nblocks is determined using Table 5.9.\n(a) Brickwork. The basic characteristic strengths\nof masonry built with standard format bricks and\nmortar designations (i)–(iv) (Table 5.6) are obtained\nfrom Table 5.9(a). Standard format bricks are\nbricks having no more than 25 per cent of formed\nvoids or 20 per cent frogs. The values in the table\nmay be modified where the following conditions,\namongst others, apply:\n1. If the horizontal cross-sectional area of the\nloaded wall (A) is less than 0.2 m2, the basic\ncompressive strength should be multiplied by\nthe factor (0.7 + 1.5A) (clause 19.1.2, BS 5628).\n2. When brick walls are constructed so that the\nthickness of the wall or loaded inner leaf of a\ncavity wall is equal to the width of a standard\nformat brick, the characteristic compressive\nstrength obtained from Table 5.9(a) may be\nmultiplied by 1.15 (clause 19.1.3, BS 5628).\n(b) Blockwork. Table 5.9(c), (d) and (f ) are\nused, singly or in combination, to determine the\nbasic characteristic compressive strength of con-\ncrete blockwork masonry. As in the case of brick\nmasonry, the values given in these tables may be\nTable 5.8\nPartial factors of safety on loading, γf, for various load combinations\nLoad combinations\nUltimate limit state\nDead\nImposed\nWind\nDead and imposed\n1.4Gk or 0.9Gk\n1.6Q k\nDead and wind\n1.4Gk or 0.9Gk\nThe larger of 1.4Wk or 0.015Gk\nDead, imposed and wind\n1.2Gk\n1.2Q k\nThe larger of 1.2Wk or 0.015Gk\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"Design of vertically loaded masonry walls\"}, {\"0\": \"Table 5.8Partial factors of safety on loading, γ\", \"1\": \"f, for various load combinations\"}, {\"0\": \"Load combinations\", \"1\": \"Ultimate limit state\"}, {\"0\": \"Dead\", \"1\": \"ImposedWind\"}, {\"0\": \"Dead and imposed1.4Gk or 0.9Gk\", \"1\": \"1.6Q k\"}, {\"0\": \"Dead and wind1.4Gk or 0.9Gk\", \"1\": \"The larger of 1.4Wk or 0.015Gk\"}, {\"0\": \"Dead, imposed and wind1.2Gk\", \"1\": \"1.2Q kThe larger of 1.2Wk or 0.015Gk\"}, {\"0\": \"5.5.1.1 Characteristic loads (clause 17,\", \"1\": \"Each  of  these  factors  is  discussed  in  the following\"}, {\"0\": \"BS 5628)\", \"1\": \"sections.\"}, {\"0\": \"The  characteristic  values  of  dead  loads  (Gk)  and\", \"1\": \"5.5.2.1 Characteristic compressive strengths of\"}, {\"0\": \"imposed loads (Qk) are obtained from the following:\", \"1\": \"\"}, {\"0\": \"(i) BS 648: Schedule of Weights for Building Materials;(ii) BS 6399: Design Loadings for Buildings, Part 1:\", \"1\": \"masonry, fk (clause 19, BS 5628)The  basic  characteristic  compressive  strengths  of\"}, {\"0\": \"Code of Practice for Dead and Imposed Loads, Part 3:\", \"1\": \"normally  bonded  masonry  constructed  under  lab-\"}, {\"0\": \"Code of Practice for Imposed Roof Loads. The charac-\", \"1\": \"oratory conditions and tested at an age of 28 days\"}, {\"0\": \"teristic wind load (Wk) is calculated in accordance\", \"1\": \"are  given  in  Table  5.9.  As  will  be  noted  from  the\"}, {\"0\": \"with BS 6399: Part 2: Wind loads.\", \"1\": \"table,  the  compressive  strength is  a  function  of\"}, {\"0\": \"\", \"1\": \"several factors including the type  and size  of\"}, {\"0\": \"5.5.1.2 Partial safety factors for loads (γf)\", \"1\": \"masonry unit, percentage of formed voids or frogs,\"}, {\"0\": \"(clause 18, BS 5628)\", \"1\": \"compressive  strength  of  the  unit  and  designation/\"}, {\"0\": \"As  discussed  in  section  2.3.2,  the  applied  loads\", \"1\": \"strength  class  of  the  mortar  used.  The  following\"}, {\"0\": \"may  be  greater  than  anticipated  for  a  number  of\", \"1\": \"discusses  how  the  characteristic  strength  of  ma-\"}, {\"0\": \"reasons.  Therefore,  it  is  normal  practice  to  factor\", \"1\": \"sonry constructed from (a) bricks and (b) concrete\"}, {\"0\": \"up  the  characteristic  loads.  Table  5.8  shows  the\", \"1\": \"blocks is determined using Table 5.9.\"}, {\"0\": \"partial  safety  factors  on  loading  for  various  load\", \"1\": \"(a) Brickwork. The basic characteristic strengths\"}, {\"0\": \"combinations. Thus, with structures subject to only\", \"1\": \"of  masonry  built  with  standard  format  bricks  and\"}, {\"0\": \"dead  and  imposed  loads  the  partial  safety  factors\", \"1\": \"mortar designations (i)–(iv) (Table 5.6) are obtained\"}, {\"0\": \"for the ultimate limit state are usually taken to be\", \"1\": \"from  Table  5.9(a).  Standard format  bricks  are\"}, {\"0\": \"1.4 and 1.6 respectively. The ultimate design load\", \"1\": \"bricks having no more than 25 per cent of formed\"}, {\"0\": \"for this load combination is given by\", \"1\": \"voids or 20 per cent frogs. The values in the table\"}, {\"0\": \"(5.3)N = 1.4Gk + 1.6Qk\", \"1\": \"may  be  modified  where  the  following  conditions,\"}, {\"0\": \"In assessing the effect of dead, imposed and wind\", \"1\": \"amongst others, apply:\"}, {\"0\": \"load  for  the  ultimate  limit  state,  the  partial  safety\", \"1\": \"1.If the  horizontal  cross-sectional  area  of the\"}, {\"0\": \"factor  is  generally  taken  to  be  1.2  for  all  the  load\", \"1\": \"loaded  wall  (A)  is  less  than  0.2  m2,  the  basic\"}, {\"0\": \"types. Hence\", \"1\": \"compressive  strength  should  be  multiplied  by\"}, {\"0\": \"(5.4)N = 1.2(Gk + Qk + Wk)\", \"1\": \"the factor (0.7 + 1.5A) (clause 19.1.2, BS 5628).\"}, {\"0\": \"\", \"1\": \"2. When  brick  walls  are  constructed  so  that  the\"}, {\"0\": \"5.5.2 DESIGN COMPRESSIVE STRENGTH\", \"1\": \"thickness  of  the  wall  or  loaded  inner  leaf  of  a\"}, {\"0\": \"The design compressive strength of masonry is given by\", \"1\": \"cavity  wall  is  equal  to  the  width  of  a  standard\"}, {\"0\": \"\", \"1\": \"format  brick, the characteristic compressive\"}, {\"0\": \"β γfkDesign compressive strength = (5.5)\", \"1\": \"strength  obtained  from  Table  5.9(a)  may  be\"}, {\"0\": \"m\", \"1\": \"multiplied by 1.15 (clause 19.1.3, BS 5628).\"}, {\"0\": \"where\", \"1\": \"(b) Blockwork. Table  5.9(c),  (d)  and  (f )  are\"}, {\"0\": \"characteristic compressive strength of masonryf kγ\", \"1\": \"used,  singly  or  in  combination,  to  determine  the\"}, {\"0\": \"partial  safety  factor  for  materials  subject  tom\", \"1\": \"basic  characteristic  compressive  strength  of  con-\"}, {\"0\": \"compressionβ\", \"1\": \"crete  blockwork  masonry.  As  in  the  case  of  brick\"}, {\"0\": \"capacity reduction factor\", \"1\": \"masonry,  the  values  given  in  these  tables  may  be\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0268.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 269, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n248\nTable 5.9\nCharacteristic compressive strength of masonry, fk (based on Table 2, BS 5628)\n(a) Constructed with standard format bricks of clay and calcium silicate\nMortar strength\nCompressive strength of unit (N/mm2)\nclass/designation\n5\n10\n15\n20\n30\n40\n50\n75\n100\n125\n150\n(i)\n2.5\n4.0\n5.3\n6.4\n8.3\n10.0\n11.6\n15.2\n18.3\n21.2\n23.9\n(ii)\n2.5\n3.8\n4.8\n5.6\n7.1\n8.4\n9.5\n12.0\n14.2\n16.1\n17.9\n(iii)\n2.5\n3.4\n4.3\n5.0\n6.3\n7.4\n8.4\n10.5\n12.3\n14.0\n15.4\n(iv)\n2.2\n2.8\n3.6\n4.1\n5.1\n6.1\n7.1\n9.0\n10.5\n11.6\n12.7\n(c) Constructed with aggregate concrete blocks having a height to least horizontal dimensions of 0.6\nMortar strength\nCompressive strength of unit (N/mm2)\nclass/designation\n2.9\n3.6\n5.2\n7.3\n10.4\n17.5\n22.5\n30\n40 or\ngreater\n(i)\n1.4\n1.7\n2.5\n3.4\n4.4\n6.3\n7.5\n9.5\n11.2\n(ii)\n1.4\n1.7\n2.5\n3.2\n4.2\n5.5\n6.5\n7.9\n9.3\n(iii)\n1.4\n1.7\n2.5\n3.2\n4.1\n5.1\n6.0\n7.2\n8.2\n(iv)\n1.4\n1.7\n2.2\n2.8\n3.5\n4.6\n5.3\n6.2\n7.1\n(d)\nConstructed with aggregate concrete blocks having not more than 25 per cent of formed voids\n(i.e. solid) and a ratio of height to least horizontal dimensions of between 2 and 4.5\nMortar strength\nCompressive strength of unit (N/mm2)\nclass/designation\n2.9\n3.6\n5.2\n7.3\n10.4\n17.5\n22.5\n30\n40 or\ngreater\n(i)\n2.8\n3.5\n5.0\n6.8\n8.8\n12.5\n15.0\n18.7\n22.1\n(ii)\n2.8\n3.5\n5.0\n6.4\n8.4\n11.1\n13.0\n15.9\n18.7\n(iii)\n2.8\n3.5\n5.0\n6.4\n8.2\n10.1\n12.0\n14.5\n16.8\n(iv)\n2.8\n3.5\n4.4\n5.6\n7.0\n9.1\n10.5\n12.5\n14.5\n(f ) Constructed with aggregate concrete blocks having more than 25 per cent but less than 60 per cent\nof formed voids (i.e. hollow blocks) and a ratio of height to least horizontal dimensions of between\n2.0 and 4.5\nMortar\nCompressive strength of unit (N/mm2)\ndesignation\n2.8\n3.5\n5.0\n7.0\n10\n15\n20\n35 or\ngreater\n(i)\n2.8\n3.5\n5.0\n5.7\n6.1\n6.8\n7.5\n11.4\n(ii)\n2.8\n3.5\n5.0\n5.5\n5.7\n6.1\n6.5\n9.4\n(iii)\n2.8\n3.5\n5.0\n5.4\n5.5\n5.7\n5.9\n8.5\n(iv)\n2.8\n3.5\n4.4\n4.8\n4.9\n5.1\n5.3\n7.3\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"Design in unreinforced masonry to BS 5628\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"Table 5.9\", \"1\": \"\", \"2\": \"Characteristic compressive strength of masonry, fk (based on Table 2, BS 5628)\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(a) Constructed with standard format bricks of clay and calcium silicate\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"Mortar strength\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"Compressive strength of unit (N/mm 2)\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"class/designation\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"5\", \"2\": \"10\", \"3\": \"15\", \"4\": \"20\", \"5\": \"30\", \"6\": \"40\", \"7\": \"50\", \"8\": \"75\", \"9\": \"100\", \"10\": \"125\", \"11\": \"150\"}, {\"0\": \"(i)\", \"1\": \"2.5\", \"2\": \"4.0\", \"3\": \"5.3\", \"4\": \"6.4\", \"5\": \"8.3\", \"6\": \"10.0\", \"7\": \"11.6\", \"8\": \"15.2\", \"9\": \"18.3\", \"10\": \"21.2\", \"11\": \"23.9\"}, {\"0\": \"(ii)\", \"1\": \"2.5\", \"2\": \"3.8\", \"3\": \"4.8\", \"4\": \"5.6\", \"5\": \"7.1\", \"6\": \"8.4\", \"7\": \"9.5\", \"8\": \"12.0\", \"9\": \"14.2\", \"10\": \"16.1\", \"11\": \"17.9\"}, {\"0\": \"(iii)\", \"1\": \"2.5\", \"2\": \"3.4\", \"3\": \"4.3\", \"4\": \"5.0\", \"5\": \"6.3\", \"6\": \"7.4\", \"7\": \"8.4\", \"8\": \"10.5\", \"9\": \"12.3\", \"10\": \"14.0\", \"11\": \"15.4\"}, {\"0\": \"(iv)\", \"1\": \"2.2\", \"2\": \"2.8\", \"3\": \"3.6\", \"4\": \"4.1\", \"5\": \"5.1\", \"6\": \"6.1\", \"7\": \"7.1\", \"8\": \"9.0\", \"9\": \"10.5\", \"10\": \"11.6\", \"11\": \"12.7\"}, {\"0\": \"\", \"1\": \"(c) Constructed with aggregate concrete blocks having a height to least horizontal dimensions of 0.6\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"Mortar strength\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"Compressive strength of unit (N/mm 2)\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"class/designation\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"2.9\", \"2\": \"3.6\", \"3\": \"5.2\", \"4\": \"7.3\", \"5\": \"10.4\", \"6\": \"17.5\", \"7\": \"22.5\", \"8\": \"30\", \"9\": \"40 or\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"greater\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(i)\", \"1\": \"1.4\", \"2\": \"1.7\", \"3\": \"2.5\", \"4\": \"3.4\", \"5\": \"4.4\", \"6\": \"6.3\", \"7\": \"7.5\", \"8\": \"9.5\", \"9\": \"11.2\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(ii)\", \"1\": \"1.4\", \"2\": \"1.7\", \"3\": \"2.5\", \"4\": \"3.2\", \"5\": \"4.2\", \"6\": \"5.5\", \"7\": \"6.5\", \"8\": \"7.9\", \"9\": \"9.3\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(iii)\", \"1\": \"1.4\", \"2\": \"1.7\", \"3\": \"2.5\", \"4\": \"3.2\", \"5\": \"4.1\", \"6\": \"5.1\", \"7\": \"6.0\", \"8\": \"7.2\", \"9\": \"8.2\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(iv)\", \"1\": \"1.4\", \"2\": \"1.7\", \"3\": \"2.2\", \"4\": \"2.8\", \"5\": \"3.5\", \"6\": \"4.6\", \"7\": \"5.3\", \"8\": \"6.2\", \"9\": \"7.1\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(d)\", \"1\": \"Constructed with aggregate concrete blocks having not more than 25 per cent of formed voids\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"(i.e. solid) and a ratio of height to least horizontal dimensions of between 2 and 4.5\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"Mortar strength\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"Compressive strength of unit (N/mm 2)\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"class/designation\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"2.9\", \"2\": \"3.6\", \"3\": \"5.2\", \"4\": \"7.3\", \"5\": \"10.4\", \"6\": \"17.5\", \"7\": \"22.5\", \"8\": \"30\", \"9\": \"40 or\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"greater\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(i)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"6.8\", \"5\": \"8.8\", \"6\": \"12.5\", \"7\": \"15.0\", \"8\": \"18.7\", \"9\": \"22.1\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(ii)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"6.4\", \"5\": \"8.4\", \"6\": \"11.1\", \"7\": \"13.0\", \"8\": \"15.9\", \"9\": \"18.7\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(iii)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"6.4\", \"5\": \"8.2\", \"6\": \"10.1\", \"7\": \"12.0\", \"8\": \"14.5\", \"9\": \"16.8\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(iv)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"4.4\", \"4\": \"5.6\", \"5\": \"7.0\", \"6\": \"9.1\", \"7\": \"10.5\", \"8\": \"12.5\", \"9\": \"14.5\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"(f ) Constructed with aggregate concrete blocks having more than 25 per cent but less than 60 per cent\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"of formed voids (i.e. hollow blocks) and a ratio of height to least horizontal dimensions of between\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"2.0 and 4.5\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"Mortar\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"Compressive strength of unit (N/mm 2)\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"designation\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"7.0\", \"5\": \"10\", \"6\": \"15\", \"7\": \"20\", \"8\": \"35 or\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"greater\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(i)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"5.7\", \"5\": \"6.1\", \"6\": \"6.8\", \"7\": \"7.5\", \"8\": \"11.4\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(ii)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"5.5\", \"5\": \"5.7\", \"6\": \"6.1\", \"7\": \"6.5\", \"8\": \"9.4\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(iii)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"5.0\", \"4\": \"5.4\", \"5\": \"5.5\", \"6\": \"5.7\", \"7\": \"5.9\", \"8\": \"8.5\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"(iv)\", \"1\": \"2.8\", \"2\": \"3.5\", \"3\": \"4.4\", \"4\": \"4.8\", \"5\": \"4.9\", \"6\": \"5.1\", \"7\": \"5.3\", \"8\": \"7.3\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}, {\"0\": \"248\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\", \"5\": \"\", \"6\": \"\", \"7\": \"\", \"8\": \"\", \"9\": \"\", \"10\": \"\", \"11\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0269.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 270, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n249\n5.5.2.2 Partial safety factor for materials (γm)\nTable 5.10 shows recommended values of the\npartial safety factor for materials, γm, for use in\ndetermining the design compressive strength of\nmasonry. The table also gives values of γm to be\nused in assessing the design strength of masonry in\nflexural. Note that the values of γm used for flexure\nare generally lower than the corresponding values\nfor compression. This is different from the 1978\nedition of BS 5628 in which they are identical.\nIt will be seen from Table 5.10 that γm depends\non (i) the quality of the masonry units and (ii) the\nquality control during construction. Moreover,\nthere are two levels of control in each case. The\nquality of masonry units may be Category I or\nCategory II, which indicates the consistency of the\nstrength of the units. Category I units are those\nwith a declared compressive strength with a prob-\nability of failure to reach that strength not exceed-\ning 5 per cent whereas Category II units are those\nthat do not conform to this condition. It is the\nmanufacturer’s responsibility to declare the category\nof the masonry units supplied. The categories of\nmasonry construction control are ‘normal’ and ‘spe-\ncial’. For design purposes it is usual to assume that\nthe category of construction control is ‘normal’\nunless the provisions outlined in clause 23.2.2.2\n(BS 5628) relating to the ‘special’ category can\nclearly be met.\n5.5.2.3 Capacity reduction factor (β)\nMasonry walls which are tall and slender are\nlikely to be less stable under compressive loading\nthan walls which are short and stocky. Similarly,\neccentric loading will reduce the compressive load\ncapacity of the wall. In both cases, the reduction in\nload capacity reflects the increased risk of failure\ndue to instability rather than crushing of the\nmaterials. These two effects are taken into account\nby means of the capacity reduction factor, β\n(Table 5.11). This factor generally reduces the\nFig. 5.9 Principal dimensions of blocks.\nmodified where the cross-sectional area of loaded\nwall is less than 0.2 m2 (see above).\nTable 5.9(c) applies to masonry constructed\nusing any type of aggregate concrete block having\na ratio of height to least horizontal dimension of\n0.6 (Fig. 5.9). Table 5.9(d) applies to masonry con-\nstructed using solid concrete blocks (i.e. blocks\nhaving not more than 25 per cent of formed voids)\nand a ratio of height to least horizontal dimension\nof between 2 and 4.5. Table 5.9(f) applies to ma-\nsonry constructed using hollow blocks (i.e. blocks\nhaving more than 25 per cent but less than 60 per\ncent of formed voids) and a ratio of height to least\nhorizontal dimension of between 2 and 4.5.\nWhen walls are constructed using aggregate con-\ncrete blocks having less than 25 per cent of formed\nvoids and a ratio of height to least horizontal dimen-\nsion of between 0.6 and 2.0, the characteristic\nstrengths should be determined by interpolating\nbetween the values in Table 5.9(c) and (d).\nWhen walls are constructed using aggregate con-\ncrete blocks having more than 25 per cent and less\nthan 60 per cent of formed voids and a ratio of\nheight to least horizontal dimension of between\n0.6 and 2.0, the characteristic strengths should be\ndetermined by interpolating between the values in\nTable 5.9(c) and 5.9(f).\nDesign of vertically loaded masonry walls\nTable 5.10\nPartial safety factors for materials, γm (Table 4,\nBS 5628)\nCategory of masonry units\nCategory of\nconstruction control\nSpecial\nNormal\nCompression, γm\nCategory I\n2.5\n3.1\nCategory II\n2.8\n3.5\nFlexure, γm\nCategory I and II\n2.5\n3.0\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"Design of vertically loaded masonry walls\"}, {\"0\": \"\", \"1\": \"5.5.2.2 Partial safety factor for materials (γm)\"}, {\"0\": \"\", \"1\": \"Table  5.10 shows recommended  values  of the\"}, {\"0\": \"\", \"1\": \"partial  safety  factor  for  materials,  γm,  for  use  in\"}, {\"0\": \"\", \"1\": \"determining the  design  compressive  strength  of\"}, {\"0\": \"\", \"1\": \"masonry.  The  table  also  gives  values  of  γm  to  be\"}, {\"0\": \"\", \"1\": \"used in assessing the design strength of masonry in\"}, {\"0\": \"\", \"1\": \"flexural. Note that the values of γm used for flexure\"}, {\"0\": \"\", \"1\": \"are  generally  lower  than  the  corresponding  values\"}, {\"0\": \"\", \"1\": \"for  compression.  This  is  different  from  the  1978\"}, {\"0\": \"\", \"1\": \"edition of BS 5628 in which they are identical.\"}, {\"0\": \"Fig. 5.9 Principal dimensions of blocks.\", \"1\": \"It  will  be  seen  from  Table  5.10  that  γm  depends\"}, {\"0\": \"\", \"1\": \"on (i) the quality of the masonry units and (ii) the\"}, {\"0\": \"\", \"1\": \"quality  control  during  construction.  Moreover,\"}, {\"0\": \"\", \"1\": \"there  are  two  levels  of  control  in  each  case.  The\"}, {\"0\": \"modified  where  the  cross-sectional  area  of  loaded\", \"1\": \"quality  of  masonry  units  may  be  Category  I  or\"}, {\"0\": \"wall is less than 0.2 m2 (see above).\", \"1\": \"Category II, which indicates the consistency of the\"}, {\"0\": \"Table  5.9(c)  applies to  masonry  constructed\", \"1\": \"strength  of  the  units.  Category  I  units  are  those\"}, {\"0\": \"using  any  type  of  aggregate  concrete  block  having\", \"1\": \"with a declared compressive strength with a prob-\"}, {\"0\": \"a  ratio  of  height  to  least  horizontal  dimension  of\", \"1\": \"ability of failure to reach that strength not exceed-\"}, {\"0\": \"0.6 (Fig. 5.9). Table 5.9(d) applies to masonry con-\", \"1\": \"ing 5 per cent whereas Category II units are those\"}, {\"0\": \"structed  using  solid  concrete  blocks  (i.e.  blocks\", \"1\": \"that  do  not  conform  to  this  condition.  It  is  the\"}, {\"0\": \"having not more than 25 per cent of formed voids)\", \"1\": \"manufacturer’s responsibility to declare the category\"}, {\"0\": \"and a ratio of height to least horizontal dimension\", \"1\": \"of  the  masonry  units  supplied.  The  categories  of\"}, {\"0\": \"of between 2 and 4.5. Table 5.9(f ) applies to ma-\", \"1\": \"masonry construction control are ‘normal’ and ‘spe-\"}, {\"0\": \"sonry  constructed  using  hollow  blocks  (i.e.  blocks\", \"1\": \"cial’. For design purposes it is usual to assume that\"}, {\"0\": \"having more than 25 per cent but less than 60 per\", \"1\": \"the  category  of  construction  control is ‘normal’\"}, {\"0\": \"cent of formed voids) and a ratio of height to least\", \"1\": \"unless  the  provisions  outlined  in  clause  23.2.2.2\"}, {\"0\": \"horizontal dimension of between 2 and 4.5.\", \"1\": \"(BS  5628)  relating  to  the ‘special’ category  can\"}, {\"0\": \"When walls are constructed using aggregate con-\", \"1\": \"clearly be met.\"}, {\"0\": \"crete blocks having less than 25 per cent of formed\", \"1\": \"\"}, {\"0\": \"voids and a ratio of height to least horizontal dimen-\", \"1\": \"5.5.2.3 Capacity reduction factor (β)\"}, {\"0\": \"sion  of  between  0.6  and  2.0,  the  characteristic\", \"1\": \"Masonry  walls  which  are tall  and slender  are\"}, {\"0\": \"strengths  should  be  determined  by  interpolating\", \"1\": \"likely  to  be  less  stable  under  compressive  loading\"}, {\"0\": \"between the values in Table 5.9(c) and (d).\", \"1\": \"than  walls  which  are  short  and  stocky.  Similarly,\"}, {\"0\": \"When walls are constructed using aggregate con-\", \"1\": \"eccentric loading will reduce the compressive load\"}, {\"0\": \"crete blocks having more than 25 per cent and less\", \"1\": \"capacity of the wall. In both cases, the reduction in\"}, {\"0\": \"than  60  per  cent  of  formed  voids  and  a  ratio  of\", \"1\": \"load  capacity  reflects  the  increased  risk  of  failure\"}, {\"0\": \"height  to  least  horizontal  dimension  of  between\", \"1\": \"due to instability rather than  crushing  of the\"}, {\"0\": \"0.6 and 2.0, the characteristic strengths should be\", \"1\": \"materials. These two effects are taken into account\"}, {\"0\": \"determined by interpolating between the values in\", \"1\": \"by  means  of the  capacity reduction factor,  β\"}, {\"0\": \"Table 5.9(c) and 5.9(f ).\", \"1\": \"(Table  5.11).  This factor  generally  reduces the\"}], [{\"0\": \"due to instability rather height  to  least  horizontal  dimension  of  between\"}, {\"0\": \"materials. These two effects are taken into account0.6 and 2.0, the characteristic strengths should be\"}, {\"0\": \"by  means  of the  capacity determined by interpolating between the values in\"}, {\"0\": \"(Table  5.11).  This factor  generally  reduces\"}, {\"0\": \"Table 5.10Partial safety factors for materials, γm (Table 4,\"}, {\"0\": \"BS 5628)\"}, {\"0\": \"Category of masonry unitsCategory of\"}, {\"0\": \"construction control\"}, {\"0\": \"SpecialNormal\"}, {\"0\": \"Compression, γCategory I2.53.1m\"}, {\"0\": \"Category II2.83.5\"}, {\"0\": \"Category I and II2.53.0Flexure, γm\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0270.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 271, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n250\nlower slenderness ratios and hence higher design\nstrengths than walls which are partially fixed or\nunrestrained.\nAs can be appreciated from the above, the\nslenderness ratio depends upon the height of the\nmember, the cross-sectional area of loaded wall\nand the restraints at the member ends. BS 5628\ndefines slenderness ratio, SR, as:\n    \nSR\neffective height\neffective thickness\nef\nef\n  \n  \n=\n= h\nt\n(5.6)\nThe following discusses how the (i) effective height\nand (ii) effective thickness of masonry walls are\ndetermined.\n(i) E  (hef). The effective height of\na load-bearing wall depends on the actual height\nof the member and the type of restraint at the\nwall ends. Such restraint that exists is normally\nprovided by any supported floors, roofs, etc. and\nmay be designated ‘simple’ (i.e. pin-ended) or\n‘enhanced’ (i.e. partially fixed), depending on the\nactual construction details used. Figures 5.10 and\n5.11 show typical examples of horizontal restraints\nwhich provide simple and enhanced resistance\nrespectively.\nAccording to clause 24.3.2.1 of BS 5628 the\neffective height of a wall may be taken as:\n1. 0.75 times the clear distance between lateral\nsupports which provide enhanced resistance to\nlateral movements; or\n2. the clear distance between lateral supports which\nprovide simple resistance to lateral movement.\n(ii) E  (tef). For single leaf walls\nthe effective thickness is taken as the actual thick-\nness (t) of the wall (Fig. 5.12(a)):\ntef = t\n(single leaf wall)\nTable 5.11\nCapacity reduction factor, β\n(Table 7, BS 5628)\nSlenderness ratio\nEccentricity at top of wall, ex, up to\nhef/tef\n0.05t\n0.1t\n0.2t\n0.3t\n0\n1.00\n0.88\n0.66\n0.44\n6\n1.00\n0.88\n0.66\n0.44\n8\n1.00\n0.88\n0.66\n0.44\n10\n0.97\n0.88\n0.66\n0.44\n12\n0.93\n0.87\n0.66\n0.44\n14\n0.89\n0.83\n0.66\n0.44\n16\n0.83\n0.77\n0.64\n0.44\n18\n0.77\n0.70\n0.57\n0.44\n20\n0.70\n0.64\n0.51\n0.37\n22\n0.62\n0.56\n0.43\n0.30\n24\n0.53\n0.47\n0.34\n26\n0.45\n0.38\n27\n0.40\n0.33\nFig. 5.10 Details of horizontal supports providing simple resistance.\ndesign compressive strength of elements such as\nwalls and columns, in some cases by as much as\n70 per cent, and is a function of the following fac-\ntors which are discussed below: (a) slenderness\nratio and (b) eccentricity of loading.\n(a) Slenderness ratio (SR). The slenderness\nratio indicates the type of failure which may arise\nwhen a member is subject to compressive loading.\nThus, walls which are short and stocky will have a\nlow slenderness ratio and tend to fail by crushing.\nWalls which are tall and slender will have higher\nslenderness ratios and will also fail by crushing.\nHowever, in this case, failure will arise as a result\nof excessive bending of the wall rather than direct\ncrushing of the materials. Similarly, walls which\nare rigidly fixed at their ends will tend to have\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"250\", \"3\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\"}], [], []]\n\n[FORMULAS]\ntef = t", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0271.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 272, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n251\nFig. 5.11 Details of horizontal supports providing\nenhanced resistance.\nIf the wall is stiffened with piers (Fig. 5.12(b)) in\norder to increase its load capacity, the effective\nthickness is given by\ntef = tK\n(single leaf wall stiffened with pier)\nwhere K is obtained from Table 5.12.\nFor cavity walls the effective thickness should be\ntaken as the greater of (i) two-thirds the sum of the\nactual thickness of the two leaves, i.e. 2/3(t1 + t2))\nor (ii) the actual thickness of the thicker leaf, i.e.\nt1 or t2 (Fig. 5.13(a)). Where the cavity wall is\nstiffened by piers, the effective thickness of the wall\nis taken as the greatest of (i) 2/3 (t1 + Kt2) or (ii) t1\nor (iii) Kt2 (Fig. 5.13b).\n(b) Eccentricity of vertical loading. In addi-\ntion to the slenderness ratio, the capacity reduc-\ntion factor is also a function of the eccentricity of\nloading. When considering the design of walls it\nis not realistic to assume that the loading will be\napplied truly axially but rather that it will occur at\nsome eccentricity to the centroid of the wall. This\neccentricity is normally expressed as a fraction of\nthe wall thickness.\nClause 27 of BS 5628 recommends that the loads\ntransmitted to a wall by a single floor or roof acts\nat one third of the length of the bearing surface\nfrom the loaded edge (Fig. 5.14). This is based on\nthe assumption that the stress distribution under\nthe bearing surface is triangular in shape as shown\nin Fig. 5.14.\nWhere a uniform floor is continuous over a wall,\neach span of the floor should be taken as being\nsupported individually on half the total bearing area\n(Fig. 5.15).\n5.5.3 DESIGN VERTICAL LOAD RESISTANCE OF\nWALLS (NR)\nThe foregoing has discussed how to evaluate the\ndesign compressive strength of a masonry wall\nbeing equal to the characteristic strength ( fk)\nmultiplied by the capacity reduction factor (β)\nand divided by the appropriate factor of safety for\nmaterials (γm). The characteristic strengths and\nfactors of safety for materials are obtained from\nTables 5.9 and 5.10 respectively. The effective thick-\nness and effective height of the member are used\nto determine the slenderness ratio and thence,\ntogether with the eccentricity of loading, the\ncapacity reduction factor via Table 5.11.\nThe design strength is used to estimate the\nvertical load resistance of a wall per metre length,\nNR, which is given by\nTable 5.12\nStiffness coefficient for walls\nstiffened by piers (Table 5, BS 5628)\nRatio of pier spacing\nRatio tp/t of pier thickness\n(centre to centre)\nto actual thickness of\nto pier width\nwall to which it\nis bonded\n1\n2\n3\n6\n1.0\n1.4\n2.0\n10\n1.0\n1.2\n1.4\n20\n1.0\n1.0\n1.0\nNote: Liner interpolation between the values given in\nthe table is permissible, but not extrapolation outside the\nlimits given.\nFig. 5.13 Effective thickness: (a) cavity wall; (b) cavity\nwall stiffened with piers (based on Fig. 2 of BS 5268).\nFig. 5.12 Effective thickness: (a) single leaf wall;\n(b) single leaf wall stiffened with piers (based on Fig. 2 of\nBS 5628).\nDesign of vertically loaded masonry walls\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"Design of vertically loaded masonry walls\"}, {\"0\": \"\", \"1\": \"If  the  wall  is  stiffened  with  piers  (Fig.  5.12(b))  in\"}, {\"0\": \"\", \"1\": \"order  to  increase  its  load  capacity,  the  effective\"}, {\"0\": \"\", \"1\": \"thickness is given by\"}, {\"0\": \"\", \"1\": \"(single leaf wall stiffened with pier)tef = tK\"}, {\"0\": \"\", \"1\": \"where K is obtained from Table 5.12.\"}, {\"0\": \"\", \"1\": \"For cavity walls the effective thickness should be\"}, {\"0\": \"\", \"1\": \"taken as the greater of (i) two-thirds the sum of the\"}, {\"0\": \"\", \"1\": \"actual thickness of the two leaves, i.e. 2/3(t1 + t2))or  (ii)  the  actual  thickness  of  the  thicker  leaf,  i.e.\"}, {\"0\": \"Fig. 5.11 Details of horizontal supports providing\", \"1\": \"t1  or  t2  (Fig.  5.13(a)).  Where  the  cavity  wall  isstiffened by piers, the effective thickness of the wall\"}, {\"0\": \"enhanced resistance.\", \"1\": \"is taken as the greatest of (i) 2/3 (t1 + Kt2) or (ii) t1\"}, {\"0\": \"\", \"1\": \"or (iii) Kt2 (Fig. 5.13b).\"}, {\"0\": \"\", \"1\": \"(b) Eccentricity  of  vertical  loading.In  addi-\"}, {\"0\": \"\", \"1\": \"tion  to  the  slenderness  ratio,  the  capacity  reduc-\"}, {\"0\": \"\", \"1\": \"tion  factor  is  also  a  function  of  the  eccentricity  of\"}, {\"0\": \"\", \"1\": \"loading.  When  considering  the  design  of  walls  it\"}, {\"0\": \"\", \"1\": \"is  not  realistic  to  assume  that  the  loading  will  be\"}, {\"0\": \"Fig. 5.12 Effective thickness: (a) single leaf wall;\", \"1\": \"applied truly axially but rather that it will occur at\"}, {\"0\": \"(b) single leaf wall stiffened with piers (based on Fig. 2 of\", \"1\": \"some eccentricity to the centroid of the wall. This\"}, {\"0\": \"BS 5628).\", \"1\": \"eccentricity  is  normally  expressed  as  a  fraction  of\"}, {\"0\": \"\", \"1\": \"the wall thickness.\"}, {\"0\": \"\", \"1\": \"Clause 27 of BS 5628 recommends that the loads\"}, {\"0\": \"\", \"1\": \"transmitted to a wall by a single floor or roof acts\"}, {\"0\": \"\", \"1\": \"at  one  third  of  the  length  of  the  bearing  surface\"}, {\"0\": \"\", \"1\": \"from the loaded edge (Fig. 5.14). This is based on\"}, {\"0\": \"\", \"1\": \"the  assumption  that  the  stress  distribution  under\"}, {\"0\": \"\", \"1\": \"the bearing surface is triangular in shape as shown\"}, {\"0\": \"\", \"1\": \"in Fig. 5.14.\"}, {\"0\": \"\", \"1\": \"Where a uniform floor is continuous over a wall,\"}, {\"0\": \"Fig. 5.13 Effective thickness: (a) cavity wall; (b) cavity\", \"1\": \"each  span  of  the  floor  should  be  taken  as  being\"}, {\"0\": \"wall stiffened with piers (based on Fig. 2 of BS 5268).\", \"1\": \"supported individually on half the total bearing area\"}, {\"0\": \"\", \"1\": \"(Fig. 5.15).\"}, {\"0\": \"Table 5.12Stiffness coefficient for walls\", \"1\": \"5.5.3 DESIGN VERTICAL LOAD RESISTANCE OF\"}, {\"0\": \"stiffened by piers (Table 5, BS 5628)\", \"1\": \"WALLS (NR)The  foregoing  has  discussed  how  to  evaluate  the\"}, {\"0\": \"Ratio of pier spacingRatio tp/t of pier thickness\", \"1\": \"design  compressive  strength  of  a  masonry  wall\"}, {\"0\": \"(centre to centre)to actual thickness of\", \"1\": \"being  equal to the  characteristic strength ( fk)\"}, {\"0\": \"to pier widthwall to which it\", \"1\": \"multiplied  by the  capacity  reduction factor  (β)\"}, {\"0\": \"is bonded\", \"1\": \"and divided by the appropriate factor of safety for\"}, {\"0\": \"\", \"1\": \"materials  (γm).  The  characteristic  strengths  and\"}, {\"0\": \"123\", \"1\": \"factors  of  safety  for  materials  are  obtained  from\"}, {\"0\": \"\", \"1\": \"Tables 5.9 and 5.10 respectively. The effective thick-\"}, {\"0\": \"61.01.42.0\", \"1\": \"ness  and  effective  height  of  the  member  are  used\"}, {\"0\": \"101.01.21.4\", \"1\": \"to  determine the  slenderness  ratio  and thence,\"}, {\"0\": \"201.01.01.0\", \"1\": \"together  with the eccentricity  of loading, the\"}, {\"0\": \"\", \"1\": \"capacity reduction factor via Table 5.11.\"}, {\"0\": \"Note: Liner interpolation between the values given in\", \"1\": \"The  design  strength is  used to  estimate the\"}, {\"0\": \"the table is permissible, but not extrapolation outside the\", \"1\": \"vertical load resistance of a wall per metre length,\"}, {\"0\": \"limits given.\", \"1\": \"NR, which is given by\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0272.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 273, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n252\nFig. 5.14 Eccentricity for wall supporting single floor.\nFig. 5.15 Eccentricity for wall supporting continuous floor.\n    NR\ndesign compression stress  area\n  \n=\n×\n    \n=\n×\n×\n=\n \n      \nβ\nγ\nβ\nγ\nf\nt\ntf\nk\nm\nk\nm\n1\n(5.7)\nAs stated earlier, the primary aim of design is\nto ensure that the ultimate design load does not\nexceed the design load resistance of the wall. Thus\nfrom equations 5.1, 5.2 and 5.7:\nN ≤ NR\nγf(Gk plus Qk, and/or Wk) ≤ \n    \nβ\nγ\ntfk\nm\n(5.8)\nEquation 5.8 provides the basis for the design of\nvertically loaded walls. The full design procedure\nis summarised in Fig. 5.16.\n\n[TABLES]\n[[{\"0\": \"Design in unreinforced masonry to BS 5628\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}], [{\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\", \"3\": \"\", \"4\": \"\"}], [{\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0273.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 274, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\n253\nDesign of vertically loaded masonry walls\nFig. 5.16 Design procedure for vertically loaded walls.\n\n[TABLES]\n[[{\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}, {\"0\": \"\", \"1\": \"\", \"2\": \"\"}], [{\"0\": \"\", \"1\": \"\"}, {\"0\": \"\", \"1\": \"\"}], [], []]", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0274.png"}
{"pdf_file": "Design of Structural Elements_ Concrete, Steelwork, Masonry and Timber Designs to British Standards and Eurocodes, 3rd Edition   ( PDFDrive ).pdf", "page_num": 275, "prompt": "Analyze this page with diagrams, tables, formulas, calculations, and explanations.", "response": "[NATIVE TEXT]\nDesign in unreinforced masonry to BS 5628\n254\nExample 5.1 Design of a load-bearing brick wall (BS 5628)\nThe internal load-bearing brick wall shown in Fig. 5.17 supports an ultimate axial load of 140 kN per metre run\nincluding self-weight of the wall. The wall is 102.5 mm thick and 4 m long. Assuming the masonry units conform to\nCategory II and the construction control category is ‘normal’, design the wall.\nLOADING\nUltimate design load, N = 140 kN m−1 = 140 N mm−1\nDESIGN VERTICAL LOAD RESISTANCE OF WALL\nCharacteristic compressive strength\nBasic value = fk\nCheck modification factor\nSmall plan area – modification factor does not apply since horizontal cross-sectional area of wall, A = 0.1025 × 4.0\n= 0.41 m2 > 0.2 m2.\nNarrow brick wall – modification factor is 1.15 since wall is one brick thick.\nHence modified characteristic compressive strength is 1.15fk\nSafety factor for materials (γm)\nManufacture and construction controls categories are, respectively, ‘II’ and ‘normal’. Hence from Table 5.10, γm for\ncompression = 3.5\nCapacity reduction factor (β)\nEccentricity\nSince wall is axially loaded assume eccentricity of loading, ex < 0.05t\nSlenderness ratio (SR)\nConcrete slab provides ‘enhanced’ resistance to wall:\nhef = 0.75 × height = 0.75 × 2800 = 2100 mm\ntef = actual thickness (single leaf) = 102.5 mm\n    \nSR\npermissible\nef\nef\n  \n  \n.   \n.\n  \n  \n=\n=\n=\n<\n=\nh\nt\n2100\n102 5\n10 05\n27\nHence, from Table 5.11, β = 0.68.\nFig. 5.17\n\n[TABLES]\n[[{\"0\": \"Design in unreinforced masonry to BS 5628\"}, {\"0\": \"Example 5.1 Design of a load-bearing brick wall (BS 5628)\"}, {\"0\": \"The  internal  load-bearing  brick  wall  shown  in  Fig.  5.17  supports  an  ultimate  axial  load  of  140  kN  per  metre  run\"}, {\"0\": \"including self-weight of the wall. The wall is 102.5 mm thick and 4 m long. Assuming the masonry units conform to\"}, {\"0\": \"Category II and the construction control category is ‘normal’, design the wall.\"}, {\"0\": \"Fig. 5.17\"}, {\"0\": \"LOADING\"}, {\"0\": \"Ultimate design load, N = 140 kN m−1 = 140 N mm−1\"}, {\"0\": \"DESIGN VERTICAL LOAD RESISTANCE OF WALL\"}, {\"0\": \"Characteristic compressive strength\"}, {\"0\": \"Basic value = fk\"}, {\"0\": \"Check modification factor\"}, {\"0\": \"Small plan area – modification factor does not apply since horizontal cross-sectional area of wall, A = 0.1025 × 4.0\"}, {\"0\": \"= 0.41 m2 > 0.2 m2.\"}, {\"0\": \"Narrow brick wall – modification factor is 1.15 since wall is one brick thick.\"}, {\"0\": \"Hence modified characteristic compressive strength is 1.15fk\"}, {\"0\": \"Safety factor for materials (γγγγγm)\"}, {\"0\": \"Manufacture  and  construction  controls  categories  are,  respectively,  ‘II’  and  ‘normal’.  Hence  from  Table 5.10,  γm  for\"}, {\"0\": \"compression = 3.5\"}, {\"0\": \"Capacity reduction factor (βββββ)\"}, {\"0\": \"Eccentricity\"}, {\"0\": \"Since wall is axially loaded assume eccentricity of loading, ex < 0.05t\"}, {\"0\": \"Slenderness ratio (SR)\"}, {\"0\": \"Concrete slab provides ‘enhanced’ resistance to wall:\"}, {\"0\": \"hef = 0.75 × height = 0.75 × 2800 = 2100 mm\"}, {\"0\": \"tef = actual thickness (single leaf) = 102.5 mm\"}, {\"0\": \"h t2100ef===<=SR      10 05  permissible  27\"}, {\"0\": \"102 5ef\"}, {\"0\": \"Hence, from Table 5.11, β = 0.68.\"}, {\"0\": \"254\"}], [], []]\n\n[FORMULAS]\nA = 0; 4.0\n= 0; hef = 0; height = 0; β = 0", "page_type": "mixed", "image": "Design of Structural Elements_ Concr_a6902759_p0275.png"}