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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Four Equal Spans » S Section Steel I Beam » S7 × 20
S Section Steel I Beam | Single Span | Two Equal Spans | Three Equal Spans | Four Equal Spans

For a simply supported beam in four equal spans, we compute the displacement at the middle of the first and fourth spans, and the maximum normal stress occuring at the second and fourth supports of the beam.
The tabulated data listed in this page are calculated based on the area moment of inertia (Ixx = 42.4 in4) for the S7 × 20 S Section Steel I Beam and the typical Young's modulus (E = 3.046 × 107 psi) of steels. Note that the typical yielding stress of steels can range from 1.015 × 104 to 2.970 × 105 psi. The purpose of this page is to give a rough estimation of the load-bearing capacity of this particular beam, rather than a guideline for designing actual building structures. Please check your local building codes for regulatory requirements.
Note: The weight of the beam itself is not included in the calculation.

 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 3.00 ft (lbf/ft) (in) (psi) 20.0 1.37 × 10-5 19.1 30.0 2.05 × 10-5 28.6 40.0 2.73 × 10-5 38.2 50.0 3.41 × 10-5 47.7 60.0 4.10 × 10-5 57.3 70.0 4.78 × 10-5 66.8 80.0 5.46 × 10-5 76.4 90.0 6.15 × 10-5 85.9 100 6.83 × 10-5 95.5 200 1.37 × 10-4 191 300 2.05 × 10-4 286 400 2.73 × 10-4 382 500 3.41 × 10-4 477 600 4.10 × 10-4 573 700 4.78 × 10-4 668 800 5.46 × 10-4 764 900 6.15 × 10-4 859 1000 6.83 × 10-4 955 2000 0.00137 1910 3000 0.00205 2860 4000 0.00273 3820 5000 0.00341 4770 6000 0.00410 5730 7000 0.00478 6680 8000 0.00546 7640 9000 0.00615 8590 1.00 × 104 0.00683 9550 2.00 × 104 0.0137 1.91 × 104 3.00 × 104 0.0205 2.86 × 104 4.00 × 104 0.0273 3.82 × 104 5.00 × 104 0.0341 4.77 × 104 6.00 × 104 0.0410 5.73 × 104 7.00 × 104 0.0478 6.68 × 104 8.00 × 104 0.0546 7.64 × 104 9.00 × 104 0.0615 8.59 × 104 1.00 × 105 0.0683 9.55 × 104 2.00 × 105 0.137 1.91 × 105 3.00 × 105 0.205 2.86 × 105 3.11 × 105 0.212 2.97 × 105
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 5.00 ft (lbf/ft) (in) (psi) 20.0 1.05 × 10-4 53.0 30.0 1.58 × 10-4 79.6 40.0 2.11 × 10-4 106 50.0 2.63 × 10-4 133 60.0 3.16 × 10-4 159 70.0 3.69 × 10-4 186 80.0 4.21 × 10-4 212 90.0 4.74 × 10-4 239 100 5.27 × 10-4 265 200 0.00105 530 300 0.00158 796 400 0.00211 1060 500 0.00263 1330 600 0.00316 1590 700 0.00369 1860 800 0.00421 2120 900 0.00474 2390 1000 0.00527 2650 2000 0.0105 5300 3000 0.0158 7960 4000 0.0211 1.06 × 104 5000 0.0263 1.33 × 104 6000 0.0316 1.59 × 104 7000 0.0369 1.86 × 104 8000 0.0421 2.12 × 104 9000 0.0474 2.39 × 104 1.00 × 104 0.0527 2.65 × 104 2.00 × 104 0.105 5.30 × 104 3.00 × 104 0.158 7.96 × 104 4.00 × 104 0.211 1.06 × 105 5.00 × 104 0.263 1.33 × 105 6.00 × 104 0.316 1.59 × 105 7.00 × 104 0.369 1.86 × 105 8.00 × 104 0.421 2.12 × 105 9.00 × 104 0.474 2.39 × 105 1.00 × 105 0.527 2.65 × 105 1.12 × 105 0.590 2.97 × 105
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 10.0 ft (lbf/ft) (in) (psi) 20.0 0.00169 212 30.0 0.00253 318 40.0 0.00337 424 50.0 0.00421 530 60.0 0.00506 637 70.0 0.00590 743 80.0 0.00674 849 90.0 0.00759 955 100 0.00843 1060 200 0.0169 2120 300 0.0253 3180 400 0.0337 4240 500 0.0421 5300 600 0.0506 6370 700 0.0590 7430 800 0.0674 8490 900 0.0759 9550 1000 0.0843 1.06 × 104 2000 0.169 2.12 × 104 3000 0.253 3.18 × 104 4000 0.337 4.24 × 104 5000 0.421 5.30 × 104 6000 0.506 6.37 × 104 7000 0.590 7.43 × 104 8000 0.674 8.49 × 104 9000 0.759 9.55 × 104 1.00 × 104 0.843 1.06 × 105 2.00 × 104 1.69 2.12 × 105 2.80 × 104 2.36 2.97 × 105
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 15.0 ft (lbf/ft) (in) (psi) 20.0 0.00854 477 30.0 0.0128 716 40.0 0.0171 955 50.0 0.0213 1190 60.0 0.0256 1430 70.0 0.0299 1670 80.0 0.0341 1910 90.0 0.0384 2150 100 0.0427 2390 200 0.0854 4770 300 0.128 7160 400 0.171 9550 500 0.213 1.19 × 104 600 0.256 1.43 × 104 700 0.299 1.67 × 104 800 0.341 1.91 × 104 900 0.384 2.15 × 104 1000 0.427 2.39 × 104 2000 0.854 4.77 × 104 3000 1.28 7.16 × 104 4000 1.71 9.55 × 104 5000 2.13 1.19 × 105 6000 2.56 1.43 × 105 7000 2.99 1.67 × 105 8000 3.41 1.91 × 105 9000 3.84 2.15 × 105 1.00 × 104 4.27 2.39 × 105 1.24 × 104 5.31 2.97 × 105
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 20.0 ft (lbf/ft) (in) (psi) 20.0 0.0270 849 30.0 0.0405 1270 40.0 0.0540 1700 50.0 0.0674 2120 60.0 0.0809 2550 70.0 0.0944 2970 80.0 0.108 3390 90.0 0.121 3820 100 0.135 4240 200 0.270 8490 300 0.405 1.27 × 104 400 0.540 1.70 × 104 500 0.674 2.12 × 104 600 0.809 2.55 × 104 700 0.944 2.97 × 104 800 1.08 3.39 × 104 900 1.21 3.82 × 104 1000 1.35 4.24 × 104 2000 2.70 8.49 × 104 3000 4.05 1.27 × 105 4000 5.40 1.70 × 105 5000 6.74 2.12 × 105 5190 7.00 2.20 × 105
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 25.0 ft (lbf/ft) (in) (psi) 20.0 0.0659 1330 30.0 0.0988 1990 40.0 0.132 2650 50.0 0.165 3320 60.0 0.198 3980 70.0 0.231 4640 80.0 0.263 5300 90.0 0.296 5970 100 0.329 6630 200 0.659 1.33 × 104 300 0.988 1.99 × 104 400 1.32 2.65 × 104 500 1.65 3.32 × 104 600 1.98 3.98 × 104 700 2.31 4.64 × 104 800 2.63 5.30 × 104 900 2.96 5.97 × 104 1000 3.29 6.63 × 104 2000 6.59 1.33 × 105 2130 7.00 1.41 × 105
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 30.0 ft (lbf/ft) (in) (psi) 20.0 0.137 1910 30.0 0.205 2860 40.0 0.273 3820 50.0 0.341 4770 60.0 0.410 5730 70.0 0.478 6680 80.0 0.546 7640 90.0 0.615 8590 100 0.683 9550 200 1.37 1.91 × 104 300 2.05 2.86 × 104 400 2.73 3.82 × 104 500 3.41 4.77 × 104 600 4.10 5.73 × 104 700 4.78 6.68 × 104 800 5.46 7.64 × 104 900 6.15 8.59 × 104 1000 6.83 9.55 × 104 1030 7.00 9.79 × 104
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 40.0 ft (lbf/ft) (in) (psi) 20.0 0.432 3390 30.0 0.647 5090 40.0 0.863 6790 50.0 1.08 8490 60.0 1.29 1.02 × 104 70.0 1.51 1.19 × 104 80.0 1.73 1.36 × 104 90.0 1.94 1.53 × 104 100 2.16 1.70 × 104 200 4.32 3.39 × 104 300 6.47 5.09 × 104 324 7.00 5.51 × 104
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 50.0 ft (lbf/ft) (in) (psi) 20.0 1.05 5300 30.0 1.58 7960 40.0 2.11 1.06 × 104 50.0 2.63 1.33 × 104 60.0 3.16 1.59 × 104 70.0 3.69 1.86 × 104 80.0 4.21 2.12 × 104 90.0 4.74 2.39 × 104 100 5.27 2.65 × 104 133 7.00 3.52 × 104
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 60.0 ft (lbf/ft) (in) (psi) 20.0 2.19 7640 30.0 3.28 1.15 × 104 40.0 4.37 1.53 × 104 50.0 5.46 1.91 × 104 60.0 6.56 2.29 × 104 64.1 7.00 2.45 × 104
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 70.0 ft (lbf/ft) (in) (psi) 20.0 4.05 1.04 × 104 30.0 6.07 1.56 × 104 34.6 7.00 1.80 × 104
 Steel I Beam: S7 × 20 (S7 inch tall × 20 lbf/ft) L = 80.0 ft (lbf/ft) (in) (psi) 20.0 6.91 1.36 × 104 20.3 7.00 1.38 × 104
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