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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Single Span » Wide Flange Steel I Beam » W18 × 71
Wide Flange Steel I Beam | Single Span | Two Equal Spans | Three Equal Spans | Four Equal Spans

For a simply supported beam in a single span, the maximum displacement w_max and the maximum normal stress stress_max occur at the center of the beam.
The tabulated data listed in this page are calculated based on the area moment of inertia (Ixx = 1170 in4) for the W18 × 71 Wide Flange Steel I Beam and the typical Young's modulus (E = 3.046 × 107 psi) of steels. Note that the typical yielding stress Yield 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.
L = 3 ft
L = 5 ft
L = 10 ft
L = 15 ft
L = 20 ft
L = 25 ft
L = 30 ft
L = 40 ft
L = 50 ft
L = 60 ft
L = 70 ft
L = 80 ft
L = 90 ft
L = 100 ft
L = 125 ft
   
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 3.63 × 10-6 7.57
80.0 4.09 × 10-6 8.52
90.0 4.60 × 10-6 9.59
100 5.11 × 10-6 10.7
200 1.02 × 10-5 21.3
300 1.53 × 10-5 32.0
400 2.05 × 10-5 42.6
500 2.56 × 10-5 53.3
600 3.07 × 10-5 63.9
700 3.58 × 10-5 74.6
800 4.09 × 10-5 85.2
900 4.60 × 10-5 95.9
1000 5.11 × 10-5 107
2000 1.02 × 10-4 213
3000 1.53 × 10-4 320
4000 2.05 × 10-4 426
5000 2.56 × 10-4 533
6000 3.07 × 10-4 639
7000 3.58 × 10-4 746
8000 4.09 × 10-4 852
9000 4.60 × 10-4 959
1.00 × 104 5.11 × 10-4 1070
2.00 × 104 0.00102 2130
3.00 × 104 0.00153 3200
4.00 × 104 0.00205 4260
5.00 × 104 0.00256 5330
6.00 × 104 0.00307 6390
7.00 × 104 0.00358 7460
8.00 × 104 0.00409 8520
9.00 × 104 0.00460 9590
1.00 × 105 0.00511 1.07 × 104
2.00 × 105 0.0102 2.13 × 104
3.00 × 105 0.0153 3.20 × 104
4.00 × 105 0.0205 4.26 × 104
5.00 × 105 0.0256 5.33 × 104
6.00 × 105 0.0307 6.39 × 104
7.00 × 105 0.0358 7.46 × 104
8.00 × 105 0.0409 8.52 × 104
9.00 × 105 0.0460 9.59 × 104
1.00 × 106 0.0511 1.07 × 105
2.00 × 106 0.102 2.13 × 105
2.79 × 106 0.143 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 2.80 × 10-5 21.0
80.0 3.16 × 10-5 23.7
90.0 3.55 × 10-5 26.6
100 3.95 × 10-5 29.6
200 7.89 × 10-5 59.2
300 1.18 × 10-4 88.8
400 1.58 × 10-4 118
500 1.97 × 10-4 148
600 2.37 × 10-4 178
700 2.76 × 10-4 207
800 3.16 × 10-4 237
900 3.55 × 10-4 266
1000 3.95 × 10-4 296
2000 7.89 × 10-4 592
3000 0.00118 888
4000 0.00158 1180
5000 0.00197 1480
6000 0.00237 1780
7000 0.00276 2070
8000 0.00316 2370
9000 0.00355 2660
1.00 × 104 0.00395 2960
2.00 × 104 0.00789 5920
3.00 × 104 0.0118 8880
4.00 × 104 0.0158 1.18 × 104
5.00 × 104 0.0197 1.48 × 104
6.00 × 104 0.0237 1.78 × 104
7.00 × 104 0.0276 2.07 × 104
8.00 × 104 0.0316 2.37 × 104
9.00 × 104 0.0355 2.66 × 104
1.00 × 105 0.0395 2.96 × 104
2.00 × 105 0.0789 5.92 × 104
3.00 × 105 0.118 8.88 × 104
4.00 × 105 0.158 1.18 × 105
5.00 × 105 0.197 1.48 × 105
6.00 × 105 0.237 1.78 × 105
7.00 × 105 0.276 2.07 × 105
8.00 × 105 0.316 2.37 × 105
9.00 × 105 0.355 2.66 × 105
1.00 × 106 0.395 2.96 × 105
1.00 × 106 0.396 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 4.48 × 10-4 84.1
80.0 5.05 × 10-4 94.7
90.0 5.68 × 10-4 107
100 6.31 × 10-4 118
200 0.00126 237
300 0.00189 355
400 0.00253 474
500 0.00316 592
600 0.00379 710
700 0.00442 829
800 0.00505 947
900 0.00568 1070
1000 0.00631 1180
2000 0.0126 2370
3000 0.0189 3550
4000 0.0253 4740
5000 0.0316 5920
6000 0.0379 7100
7000 0.0442 8290
8000 0.0505 9470
9000 0.0568 1.07 × 104
1.00 × 104 0.0631 1.18 × 104
2.00 × 104 0.126 2.37 × 104
3.00 × 104 0.189 3.55 × 104
4.00 × 104 0.253 4.74 × 104
5.00 × 104 0.316 5.92 × 104
6.00 × 104 0.379 7.10 × 104
7.00 × 104 0.442 8.29 × 104
8.00 × 104 0.505 9.47 × 104
9.00 × 104 0.568 1.07 × 105
1.00 × 105 0.631 1.18 × 105
2.00 × 105 1.26 2.37 × 105
2.51 × 105 1.58 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.00227 189
80.0 0.00256 213
90.0 0.00288 240
100 0.00320 266
200 0.00639 533
300 0.00959 799
400 0.0128 1070
500 0.0160 1330
600 0.0192 1600
700 0.0224 1860
800 0.0256 2130
900 0.0288 2400
1000 0.0320 2660
2000 0.0639 5330
3000 0.0959 7990
4000 0.128 1.07 × 104
5000 0.160 1.33 × 104
6000 0.192 1.60 × 104
7000 0.224 1.86 × 104
8000 0.256 2.13 × 104
9000 0.288 2.40 × 104
1.00 × 104 0.320 2.66 × 104
2.00 × 104 0.639 5.33 × 104
3.00 × 104 0.959 7.99 × 104
4.00 × 104 1.28 1.07 × 105
5.00 × 104 1.60 1.33 × 105
6.00 × 104 1.92 1.60 × 105
7.00 × 104 2.24 1.86 × 105
8.00 × 104 2.56 2.13 × 105
9.00 × 104 2.88 2.40 × 105
1.00 × 105 3.20 2.66 × 105
1.12 × 105 3.56 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.00717 336
80.0 0.00808 379
90.0 0.00909 426
100 0.0101 474
200 0.0202 947
300 0.0303 1420
400 0.0404 1890
500 0.0505 2370
600 0.0606 2840
700 0.0707 3320
800 0.0808 3790
900 0.0909 4260
1000 0.101 4740
2000 0.202 9470
3000 0.303 1.42 × 104
4000 0.404 1.89 × 104
5000 0.505 2.37 × 104
6000 0.606 2.84 × 104
7000 0.707 3.32 × 104
8000 0.808 3.79 × 104
9000 0.909 4.26 × 104
1.00 × 104 1.01 4.74 × 104
2.00 × 104 2.02 9.47 × 104
3.00 × 104 3.03 1.42 × 105
4.00 × 104 4.04 1.89 × 105
5.00 × 104 5.05 2.37 × 105
6.00 × 104 6.06 2.84 × 105
6.27 × 104 6.34 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.0175 525
80.0 0.0197 592
90.0 0.0222 666
100 0.0247 740
200 0.0493 1480
300 0.0740 2220
400 0.0987 2960
500 0.123 3700
600 0.148 4440
700 0.173 5180
800 0.197 5920
900 0.222 6660
1000 0.247 7400
2000 0.493 1.48 × 104
3000 0.740 2.22 × 104
4000 0.987 2.96 × 104
5000 1.23 3.70 × 104
6000 1.48 4.44 × 104
7000 1.73 5.18 × 104
8000 1.97 5.92 × 104
9000 2.22 6.66 × 104
1.00 × 104 2.47 7.40 × 104
2.00 × 104 4.93 1.48 × 105
3.00 × 104 7.40 2.22 × 105
4.00 × 104 9.87 2.96 × 105
4.01 × 104 9.90 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.0363 757
80.0 0.0409 852
90.0 0.0460 959
100 0.0511 1070
200 0.102 2130
300 0.153 3200
400 0.205 4260
500 0.256 5330
600 0.307 6390
700 0.358 7460
800 0.409 8520
900 0.460 9590
1000 0.511 1.07 × 104
2000 1.02 2.13 × 104
3000 1.53 3.20 × 104
4000 2.05 4.26 × 104
5000 2.56 5.33 × 104
6000 3.07 6.39 × 104
7000 3.58 7.46 × 104
8000 4.09 8.52 × 104
9000 4.60 9.59 × 104
1.00 × 104 5.11 1.07 × 105
2.00 × 104 10.2 2.13 × 105
2.79 × 104 14.3 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.115 1340
80.0 0.129 1520
90.0 0.145 1700
100 0.162 1890
200 0.323 3790
300 0.485 5680
400 0.647 7580
500 0.808 9470
600 0.970 1.14 × 104
700 1.13 1.33 × 104
800 1.29 1.52 × 104
900 1.45 1.70 × 104
1000 1.62 1.89 × 104
2000 3.23 3.79 × 104
3000 4.85 5.68 × 104
4000 6.47 7.58 × 104
5000 8.08 9.47 × 104
6000 9.70 1.14 × 105
7000 11.3 1.33 × 105
8000 12.9 1.52 × 105
9000 14.5 1.70 × 105
1.00 × 104 16.2 1.89 × 105
1.57 × 104 25.3 2.97 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.280 2100
80.0 0.316 2370
90.0 0.355 2660
100 0.395 2960
200 0.789 5920
300 1.18 8880
400 1.58 1.18 × 104
500 1.97 1.48 × 104
600 2.37 1.78 × 104
700 2.76 2.07 × 104
800 3.16 2.37 × 104
900 3.55 2.66 × 104
1000 3.95 2.96 × 104
2000 7.89 5.92 × 104
3000 11.8 8.88 × 104
4000 15.8 1.18 × 105
4680 18.5 1.39 × 105
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 60.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 0.581 3030
80.0 0.655 3410
90.0 0.736 3840
100 0.818 4260
200 1.64 8520
300 2.45 1.28 × 104
400 3.27 1.70 × 104
500 4.09 2.13 × 104
600 4.91 2.56 × 104
700 5.73 2.98 × 104
800 6.55 3.41 × 104
900 7.36 3.84 × 104
1000 8.18 4.26 × 104
2000 16.4 8.52 × 104
2260 18.5 9.62 × 104
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 70.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 1.08 4120
80.0 1.21 4640
90.0 1.36 5220
100 1.52 5800
200 3.03 1.16 × 104
300 4.55 1.74 × 104
400 6.06 2.32 × 104
500 7.58 2.90 × 104
600 9.10 3.48 × 104
700 10.6 4.06 × 104
800 12.1 4.64 × 104
900 13.6 5.22 × 104
1000 15.2 5.80 × 104
1220 18.5 7.07 × 104
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 80.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 1.84 5380
80.0 2.07 6060
90.0 2.33 6820
100 2.59 7580
200 5.17 1.52 × 104
300 7.76 2.27 × 104
400 10.3 3.03 × 104
500 12.9 3.79 × 104
600 15.5 4.55 × 104
700 18.1 5.30 × 104
714 18.5 5.41 × 104
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 90.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 2.94 6810
80.0 3.31 7670
90.0 3.73 8630
100 4.14 9590
200 8.29 1.92 × 104
300 12.4 2.88 × 104
400 16.6 3.84 × 104
446 18.5 4.28 × 104
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 100 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 4.48 8410
80.0 5.05 9470
90.0 5.68 1.07 × 104
100 6.31 1.18 × 104
200 12.6 2.37 × 104
293 18.5 3.46 × 104
Steel I Beam: W18 × 71 (Wide Flange 18 inch tall × 71 lbf/ft)
L = 125 ft
P (lbf/ft) w_max (in) stress_max (psi)
71.0 10.9 1.31 × 104
80.0 12.3 1.48 × 104
90.0 13.9 1.66 × 104
100 15.4 1.85 × 104
120 18.5 2.22 × 104
Additional Information
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