File size: 5,752 Bytes
7c60059 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 | """
Unit tests for RectangularBeam calculator
Tests based on ACI 318 Example 4-1 (Imperial) and 4-1M (SI)
"""
import unittest
import math
from calculator import RectangularBeam
class TestRectangularBeamImperial(unittest.TestCase):
"""Tests for Imperial unit calculations (Example 4-1)."""
def setUp(self):
"""Set up beam with Example 4-1 values."""
self.beam = RectangularBeam(
b=12.0,
h=20.0,
d=17.5,
fc=4000.0,
fy=60000.0,
n_bars=4,
bar_area=0.79, # 4 x No. 8 bars
unit_system="imperial"
)
self.results = self.beam.calculate_mn()
def test_steel_area(self):
"""Test As = n_bars * bar_area."""
expected_As = 4 * 0.79 # 3.16 in2
self.assertAlmostEqual(self.results["As"], expected_As, places=2)
def test_stress_block_depth_a(self):
"""Test a = (As * fy) / (0.85 * fc * b)."""
# a = (3.16 * 60000) / (0.85 * 4000 * 12) = 4.647 in
self.assertAlmostEqual(self.results["a"], 4.647, delta=0.01)
def test_neutral_axis_depth_c(self):
"""Test c = a / beta1."""
# c = 4.647 / 0.85 = 5.467 in
expected_c = self.results["a"] / 0.85
self.assertAlmostEqual(self.results["c"], expected_c, delta=0.01)
def test_nominal_moment(self):
"""Test Mn calculation."""
# Mn = As * fy * (d - a/2) / 12000 k-ft
# Mn = 3.16 * 60000 * (17.5 - 4.647/2) / 12000 = 239.79 k-ft
self.assertAlmostEqual(self.results["Mn_display"], 239.79, delta=0.5)
def test_tension_controlled(self):
"""Test that beam is tension controlled (epsilon_t >= 0.005)."""
self.assertGreaterEqual(self.results["epsilon_t"], 0.005)
self.assertEqual(self.results["phi"], 0.9)
def test_yield_check(self):
"""Test that steel yields."""
self.assertTrue(self.results["yield_check"])
def test_minimum_steel_check(self):
"""Test minimum steel area calculation."""
# As_min for fc=4000, fy=60000, b=12, d=17.5
As_min = self.results["As_min"]
self.assertGreater(As_min, 0)
self.assertTrue(self.results["as_check"]) # As >= As_min
class TestRectangularBeamSI(unittest.TestCase):
"""Tests for SI unit calculations (Example 4-1M)."""
def setUp(self):
"""Set up beam with Example 4-1M values."""
self.beam = RectangularBeam(
b=250.0,
h=565.0,
d=500.0,
fc=20.0,
fy=420.0,
n_bars=3,
bar_area=510.0, # 3 x 510 mm2 bars
unit_system="si"
)
self.results = self.beam.calculate_mn()
def test_steel_area(self):
"""Test As = n_bars * bar_area."""
expected_As = 3 * 510 # 1530 mm2
self.assertAlmostEqual(self.results["As"], expected_As, places=0)
def test_stress_block_depth_a(self):
"""Test a = (As * fy) / (0.85 * fc * b)."""
# a = (1530 * 420) / (0.85 * 20 * 250) = 151.76 mm
self.assertAlmostEqual(self.results["a"], 151.76, delta=1.0)
def test_yield_check(self):
"""Test that steel yields."""
self.assertTrue(self.results["yield_check"])
def test_minimum_steel_check(self):
"""Test minimum steel area calculation for SI."""
As_min = self.results["As_min"]
self.assertGreater(As_min, 0)
class TestBeta1Calculation(unittest.TestCase):
"""Tests for beta1 calculation based on fc."""
def test_beta1_low_fc_imperial(self):
"""Beta1 = 0.85 for fc <= 4000 psi."""
beam = RectangularBeam(
b=12, h=20, d=17.5, fc=4000, fy=60000,
n_bars=4, bar_area=0.79, unit_system="imperial"
)
self.assertEqual(beam.beta1, 0.85)
def test_beta1_high_fc_imperial(self):
"""Beta1 = 0.65 for fc >= 8000 psi."""
beam = RectangularBeam(
b=12, h=20, d=17.5, fc=8000, fy=60000,
n_bars=4, bar_area=0.79, unit_system="imperial"
)
self.assertEqual(beam.beta1, 0.65)
def test_beta1_mid_fc_imperial(self):
"""Beta1 interpolated for 4000 < fc < 8000 psi."""
beam = RectangularBeam(
b=12, h=20, d=17.5, fc=6000, fy=60000,
n_bars=4, bar_area=0.79, unit_system="imperial"
)
# beta1 = 0.85 - 0.05 * (6000 - 4000) / 1000 = 0.75
self.assertAlmostEqual(beam.beta1, 0.75, places=2)
def test_beta1_override(self):
"""Test that beta1 can be overridden."""
beam = RectangularBeam(
b=12, h=20, d=17.5, fc=4000, fy=60000,
n_bars=4, bar_area=0.79, beta1=0.70, unit_system="imperial"
)
self.assertEqual(beam.beta1, 0.70)
class TestEdgeCases(unittest.TestCase):
"""Tests for edge cases."""
def test_single_bar(self):
"""Test with single bar."""
beam = RectangularBeam(
b=12, h=20, d=17.5, fc=4000, fy=60000,
n_bars=1, bar_area=0.79, unit_system="imperial"
)
results = beam.calculate_mn()
self.assertEqual(results["As"], 0.79)
def test_custom_epsilon_cu(self):
"""Test with custom ultimate concrete strain."""
beam = RectangularBeam(
b=12, h=20, d=17.5, fc=4000, fy=60000,
n_bars=4, bar_area=0.79, epsilon_cu=0.0035, unit_system="imperial"
)
self.assertEqual(beam.epsilon_cu, 0.0035)
if __name__ == '__main__':
unittest.main()
|