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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Four Equal Spans » Wide Flange Steel I Beam » W18 × 35
Wide Flange 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 = 510 in4) for the W18 × 35 Wide Flange 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: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 3.00 ft (lbf/ft) (in) (psi) 35.0 1.99 × 10-6 7.03 40.0 2.27 × 10-6 8.03 50.0 2.84 × 10-6 10.0 60.0 3.41 × 10-6 12.0 70.0 3.97 × 10-6 14.1 80.0 4.54 × 10-6 16.1 90.0 5.11 × 10-6 18.1 100 5.68 × 10-6 20.1 200 1.14 × 10-5 40.1 300 1.70 × 10-5 60.2 400 2.27 × 10-5 80.3 500 2.84 × 10-5 100 600 3.41 × 10-5 120 700 3.97 × 10-5 141 800 4.54 × 10-5 161 900 5.11 × 10-5 181 1000 5.68 × 10-5 201 2000 1.14 × 10-4 401 3000 1.70 × 10-4 602 4000 2.27 × 10-4 803 5000 2.84 × 10-4 1000 6000 3.41 × 10-4 1200 7000 3.97 × 10-4 1410 8000 4.54 × 10-4 1610 9000 5.11 × 10-4 1810 1.00 × 104 5.68 × 10-4 2010 2.00 × 104 0.00114 4010 3.00 × 104 0.00170 6020 4.00 × 104 0.00227 8030 5.00 × 104 0.00284 1.00 × 104 6.00 × 104 0.00341 1.20 × 104 7.00 × 104 0.00397 1.41 × 104 8.00 × 104 0.00454 1.61 × 104 9.00 × 104 0.00511 1.81 × 104 1.00 × 105 0.00568 2.01 × 104 2.00 × 105 0.0114 4.01 × 104 3.00 × 105 0.0170 6.02 × 104 4.00 × 105 0.0227 8.03 × 104 5.00 × 105 0.0284 1.00 × 105 6.00 × 105 0.0341 1.20 × 105 7.00 × 105 0.0397 1.41 × 105 8.00 × 105 0.0454 1.61 × 105 9.00 × 105 0.0511 1.81 × 105 1.00 × 106 0.0568 2.01 × 105 1.48 × 106 0.0840 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 5.00 ft (lbf/ft) (in) (psi) 35.0 1.53 × 10-5 19.5 40.0 1.75 × 10-5 22.3 50.0 2.19 × 10-5 27.9 60.0 2.63 × 10-5 33.5 70.0 3.07 × 10-5 39.0 80.0 3.50 × 10-5 44.6 90.0 3.94 × 10-5 50.2 100 4.38 × 10-5 55.8 200 8.76 × 10-5 112 300 1.31 × 10-4 167 400 1.75 × 10-4 223 500 2.19 × 10-4 279 600 2.63 × 10-4 335 700 3.07 × 10-4 390 800 3.50 × 10-4 446 900 3.94 × 10-4 502 1000 4.38 × 10-4 558 2000 8.76 × 10-4 1120 3000 0.00131 1670 4000 0.00175 2230 5000 0.00219 2790 6000 0.00263 3350 7000 0.00307 3900 8000 0.00350 4460 9000 0.00394 5020 1.00 × 104 0.00438 5580 2.00 × 104 0.00876 1.12 × 104 3.00 × 104 0.0131 1.67 × 104 4.00 × 104 0.0175 2.23 × 104 5.00 × 104 0.0219 2.79 × 104 6.00 × 104 0.0263 3.35 × 104 7.00 × 104 0.0307 3.90 × 104 8.00 × 104 0.0350 4.46 × 104 9.00 × 104 0.0394 5.02 × 104 1.00 × 105 0.0438 5.58 × 104 2.00 × 105 0.0876 1.12 × 105 3.00 × 105 0.131 1.67 × 105 4.00 × 105 0.175 2.23 × 105 5.00 × 105 0.219 2.79 × 105 5.33 × 105 0.233 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 10.0 ft (lbf/ft) (in) (psi) 35.0 2.45 × 10-4 78.1 40.0 2.80 × 10-4 89.2 50.0 3.50 × 10-4 112 60.0 4.20 × 10-4 134 70.0 4.91 × 10-4 156 80.0 5.61 × 10-4 178 90.0 6.31 × 10-4 201 100 7.01 × 10-4 223 200 0.00140 446 300 0.00210 669 400 0.00280 892 500 0.00350 1120 600 0.00420 1340 700 0.00491 1560 800 0.00561 1780 900 0.00631 2010 1000 0.00701 2230 2000 0.0140 4460 3000 0.0210 6690 4000 0.0280 8920 5000 0.0350 1.12 × 104 6000 0.0420 1.34 × 104 7000 0.0491 1.56 × 104 8000 0.0561 1.78 × 104 9000 0.0631 2.01 × 104 1.00 × 104 0.0701 2.23 × 104 2.00 × 104 0.140 4.46 × 104 3.00 × 104 0.210 6.69 × 104 4.00 × 104 0.280 8.92 × 104 5.00 × 104 0.350 1.12 × 105 6.00 × 104 0.420 1.34 × 105 7.00 × 104 0.491 1.56 × 105 8.00 × 104 0.561 1.78 × 105 9.00 × 104 0.631 2.01 × 105 1.00 × 105 0.701 2.23 × 105 1.33 × 105 0.933 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 15.0 ft (lbf/ft) (in) (psi) 35.0 0.00124 176 40.0 0.00142 201 50.0 0.00177 251 60.0 0.00213 301 70.0 0.00248 351 80.0 0.00284 401 90.0 0.00319 452 100 0.00355 502 200 0.00710 1000 300 0.0106 1510 400 0.0142 2010 500 0.0177 2510 600 0.0213 3010 700 0.0248 3510 800 0.0284 4010 900 0.0319 4520 1000 0.0355 5020 2000 0.0710 1.00 × 104 3000 0.106 1.51 × 104 4000 0.142 2.01 × 104 5000 0.177 2.51 × 104 6000 0.213 3.01 × 104 7000 0.248 3.51 × 104 8000 0.284 4.01 × 104 9000 0.319 4.52 × 104 1.00 × 104 0.355 5.02 × 104 2.00 × 104 0.710 1.00 × 105 3.00 × 104 1.06 1.51 × 105 4.00 × 104 1.42 2.01 × 105 5.00 × 104 1.77 2.51 × 105 5.92 × 104 2.10 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 20.0 ft (lbf/ft) (in) (psi) 35.0 0.00392 312 40.0 0.00449 357 50.0 0.00561 446 60.0 0.00673 535 70.0 0.00785 624 80.0 0.00897 714 90.0 0.0101 803 100 0.0112 892 200 0.0224 1780 300 0.0336 2680 400 0.0449 3570 500 0.0561 4460 600 0.0673 5350 700 0.0785 6240 800 0.0897 7140 900 0.101 8030 1000 0.112 8920 2000 0.224 1.78 × 104 3000 0.336 2.68 × 104 4000 0.449 3.57 × 104 5000 0.561 4.46 × 104 6000 0.673 5.35 × 104 7000 0.785 6.24 × 104 8000 0.897 7.14 × 104 9000 1.01 8.03 × 104 1.00 × 104 1.12 8.92 × 104 2.00 × 104 2.24 1.78 × 105 3.00 × 104 3.36 2.68 × 105 3.33 × 104 3.73 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 25.0 ft (lbf/ft) (in) (psi) 35.0 0.00958 488 40.0 0.0110 558 50.0 0.0137 697 60.0 0.0164 836 70.0 0.0192 976 80.0 0.0219 1120 90.0 0.0246 1250 100 0.0274 1390 200 0.0548 2790 300 0.0821 4180 400 0.110 5580 500 0.137 6970 600 0.164 8360 700 0.192 9760 800 0.219 1.12 × 104 900 0.246 1.25 × 104 1000 0.274 1.39 × 104 2000 0.548 2.79 × 104 3000 0.821 4.18 × 104 4000 1.10 5.58 × 104 5000 1.37 6.97 × 104 6000 1.64 8.36 × 104 7000 1.92 9.76 × 104 8000 2.19 1.12 × 105 9000 2.46 1.25 × 105 1.00 × 104 2.74 1.39 × 105 2.00 × 104 5.48 2.79 × 105 2.13 × 104 5.83 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 30.0 ft (lbf/ft) (in) (psi) 35.0 0.0199 703 40.0 0.0227 803 50.0 0.0284 1000 60.0 0.0341 1200 70.0 0.0397 1410 80.0 0.0454 1610 90.0 0.0511 1810 100 0.0568 2010 200 0.114 4010 300 0.170 6020 400 0.227 8030 500 0.284 1.00 × 104 600 0.341 1.20 × 104 700 0.397 1.41 × 104 800 0.454 1.61 × 104 900 0.511 1.81 × 104 1000 0.568 2.01 × 104 2000 1.14 4.01 × 104 3000 1.70 6.02 × 104 4000 2.27 8.03 × 104 5000 2.84 1.00 × 105 6000 3.41 1.20 × 105 7000 3.97 1.41 × 105 8000 4.54 1.61 × 105 9000 5.11 1.81 × 105 1.00 × 104 5.68 2.01 × 105 1.48 × 104 8.40 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 40.0 ft (lbf/ft) (in) (psi) 35.0 0.0628 1250 40.0 0.0718 1430 50.0 0.0897 1780 60.0 0.108 2140 70.0 0.126 2500 80.0 0.144 2850 90.0 0.161 3210 100 0.179 3570 200 0.359 7140 300 0.538 1.07 × 104 400 0.718 1.43 × 104 500 0.897 1.78 × 104 600 1.08 2.14 × 104 700 1.26 2.50 × 104 800 1.44 2.85 × 104 900 1.61 3.21 × 104 1000 1.79 3.57 × 104 2000 3.59 7.14 × 104 3000 5.38 1.07 × 105 4000 7.18 1.43 × 105 5000 8.97 1.78 × 105 6000 10.8 2.14 × 105 7000 12.6 2.50 × 105 8000 14.4 2.85 × 105 8320 14.9 2.97 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 50.0 ft (lbf/ft) (in) (psi) 35.0 0.153 1950 40.0 0.175 2230 50.0 0.219 2790 60.0 0.263 3350 70.0 0.307 3900 80.0 0.350 4460 90.0 0.394 5020 100 0.438 5580 200 0.876 1.12 × 104 300 1.31 1.67 × 104 400 1.75 2.23 × 104 500 2.19 2.79 × 104 600 2.63 3.35 × 104 700 3.07 3.90 × 104 800 3.50 4.46 × 104 900 3.94 5.02 × 104 1000 4.38 5.58 × 104 2000 8.76 1.12 × 105 3000 13.1 1.67 × 105 4000 17.5 2.23 × 105 4040 17.7 2.25 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 60.0 ft (lbf/ft) (in) (psi) 35.0 0.318 2810 40.0 0.363 3210 50.0 0.454 4010 60.0 0.545 4820 70.0 0.636 5620 80.0 0.727 6420 90.0 0.817 7230 100 0.908 8030 200 1.82 1.61 × 104 300 2.72 2.41 × 104 400 3.63 3.21 × 104 500 4.54 4.01 × 104 600 5.45 4.82 × 104 700 6.36 5.62 × 104 800 7.27 6.42 × 104 900 8.17 7.23 × 104 1000 9.08 8.03 × 104 1950 17.7 1.56 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 70.0 ft (lbf/ft) (in) (psi) 35.0 0.589 3820 40.0 0.673 4370 50.0 0.841 5460 60.0 1.01 6560 70.0 1.18 7650 80.0 1.35 8740 90.0 1.51 9840 100 1.68 1.09 × 104 200 3.37 2.19 × 104 300 5.05 3.28 × 104 400 6.73 4.37 × 104 500 8.41 5.46 × 104 600 10.1 6.56 × 104 700 11.8 7.65 × 104 800 13.5 8.74 × 104 900 15.1 9.84 × 104 1000 16.8 1.09 × 105 1050 17.7 1.15 × 105
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 80.0 ft (lbf/ft) (in) (psi) 35.0 1.00 5000 40.0 1.15 5710 50.0 1.44 7140 60.0 1.72 8560 70.0 2.01 9990 80.0 2.30 1.14 × 104 90.0 2.58 1.28 × 104 100 2.87 1.43 × 104 200 5.74 2.85 × 104 300 8.61 4.28 × 104 400 11.5 5.71 × 104 500 14.4 7.14 × 104 600 17.2 8.56 × 104 617 17.7 8.80 × 104
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 90.0 ft (lbf/ft) (in) (psi) 35.0 1.61 6320 40.0 1.84 7230 50.0 2.30 9030 60.0 2.76 1.08 × 104 70.0 3.22 1.26 × 104 80.0 3.68 1.45 × 104 90.0 4.14 1.63 × 104 100 4.60 1.81 × 104 200 9.20 3.61 × 104 300 13.8 5.42 × 104 385 17.7 6.95 × 104
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 100 ft (lbf/ft) (in) (psi) 35.0 2.45 7810 40.0 2.80 8920 50.0 3.50 1.12 × 104 60.0 4.20 1.34 × 104 70.0 4.91 1.56 × 104 80.0 5.61 1.78 × 104 90.0 6.31 2.01 × 104 100 7.01 2.23 × 104 200 14.0 4.46 × 104 253 17.7 5.63 × 104
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 125 ft (lbf/ft) (in) (psi) 35.0 5.99 1.22 × 104 40.0 6.84 1.39 × 104 50.0 8.56 1.74 × 104 60.0 10.3 2.09 × 104 70.0 12.0 2.44 × 104 80.0 13.7 2.79 × 104 90.0 15.4 3.14 × 104 100 17.1 3.48 × 104 103 17.7 3.60 × 104
 Steel I Beam: W18 × 35 (Wide Flange 18 inch tall × 35 lbf/ft) L = 150 ft (lbf/ft) (in) (psi) 35.0 12.4 1.76 × 104 40.0 14.2 2.01 × 104 49.9 17.7 2.50 × 104
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