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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Three Equal Spans » Wide Flange Steel I Beam » W16 × 77
Wide Flange Steel I Beam | Single Span | Two Equal Spans | Three Equal Spans | Four Equal Spans

For a simply supported beam in three equal spans, we compute the displacement at the middle of the first and the third spans, and the maximum normal stress stress_max occuring at the second and third supports of the beam.
The tabulated data listed in this page are calculated based on the area moment of inertia (Ixx = 1110 in4) for the W16 × 77 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
L = 150 ft
   
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 2.17 × 10-6 6.19
80.0 2.25 × 10-6 6.43
90.0 2.53 × 10-6 7.23
100 2.82 × 10-6 8.04
200 5.63 × 10-6 16.1
300 8.45 × 10-6 24.1
400 1.13 × 10-5 32.1
500 1.41 × 10-5 40.2
600 1.69 × 10-5 48.2
700 1.97 × 10-5 56.3
800 2.25 × 10-5 64.3
900 2.53 × 10-5 72.3
1000 2.82 × 10-5 80.4
2000 5.63 × 10-5 161
3000 8.45 × 10-5 241
4000 1.13 × 10-4 321
5000 1.41 × 10-4 402
6000 1.69 × 10-4 482
7000 1.97 × 10-4 563
8000 2.25 × 10-4 643
9000 2.53 × 10-4 723
1.00 × 104 2.82 × 10-4 804
2.00 × 104 5.63 × 10-4 1610
3.00 × 104 8.45 × 10-4 2410
4.00 × 104 0.00113 3210
5.00 × 104 0.00141 4020
6.00 × 104 0.00169 4820
7.00 × 104 0.00197 5630
8.00 × 104 0.00225 6430
9.00 × 104 0.00253 7230
1.00 × 105 0.00282 8040
2.00 × 105 0.00563 1.61 × 104
3.00 × 105 0.00845 2.41 × 104
4.00 × 105 0.0113 3.21 × 104
5.00 × 105 0.0141 4.02 × 104
6.00 × 105 0.0169 4.82 × 104
7.00 × 105 0.0197 5.63 × 104
8.00 × 105 0.0225 6.43 × 104
9.00 × 105 0.0253 7.23 × 104
1.00 × 106 0.0282 8.04 × 104
2.00 × 106 0.0563 1.61 × 105
3.00 × 106 0.0845 2.41 × 105
3.70 × 106 0.104 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 1.67 × 10-5 17.2
80.0 1.74 × 10-5 17.9
90.0 1.96 × 10-5 20.1
100 2.17 × 10-5 22.3
200 4.34 × 10-5 44.6
300 6.52 × 10-5 67.0
400 8.69 × 10-5 89.3
500 1.09 × 10-4 112
600 1.30 × 10-4 134
700 1.52 × 10-4 156
800 1.74 × 10-4 179
900 1.96 × 10-4 201
1000 2.17 × 10-4 223
2000 4.34 × 10-4 446
3000 6.52 × 10-4 670
4000 8.69 × 10-4 893
5000 0.00109 1120
6000 0.00130 1340
7000 0.00152 1560
8000 0.00174 1790
9000 0.00196 2010
1.00 × 104 0.00217 2230
2.00 × 104 0.00434 4460
3.00 × 104 0.00652 6700
4.00 × 104 0.00869 8930
5.00 × 104 0.0109 1.12 × 104
6.00 × 104 0.0130 1.34 × 104
7.00 × 104 0.0152 1.56 × 104
8.00 × 104 0.0174 1.79 × 104
9.00 × 104 0.0196 2.01 × 104
1.00 × 105 0.0217 2.23 × 104
2.00 × 105 0.0434 4.46 × 104
3.00 × 105 0.0652 6.70 × 104
4.00 × 105 0.0869 8.93 × 104
5.00 × 105 0.109 1.12 × 105
6.00 × 105 0.130 1.34 × 105
7.00 × 105 0.152 1.56 × 105
8.00 × 105 0.174 1.79 × 105
9.00 × 105 0.196 2.01 × 105
1.00 × 106 0.217 2.23 × 105
1.33 × 106 0.289 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 2.68 × 10-4 68.8
80.0 2.78 × 10-4 71.4
90.0 3.13 × 10-4 80.4
100 3.48 × 10-4 89.3
200 6.95 × 10-4 179
300 0.00104 268
400 0.00139 357
500 0.00174 446
600 0.00209 536
700 0.00243 625
800 0.00278 714
900 0.00313 804
1000 0.00348 893
2000 0.00695 1790
3000 0.0104 2680
4000 0.0139 3570
5000 0.0174 4460
6000 0.0209 5360
7000 0.0243 6250
8000 0.0278 7140
9000 0.0313 8040
1.00 × 104 0.0348 8930
2.00 × 104 0.0695 1.79 × 104
3.00 × 104 0.104 2.68 × 104
4.00 × 104 0.139 3.57 × 104
5.00 × 104 0.174 4.46 × 104
6.00 × 104 0.209 5.36 × 104
7.00 × 104 0.243 6.25 × 104
8.00 × 104 0.278 7.14 × 104
9.00 × 104 0.313 8.04 × 104
1.00 × 105 0.348 8.93 × 104
2.00 × 105 0.695 1.79 × 105
3.00 × 105 1.04 2.68 × 105
3.33 × 105 1.16 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.00135 155
80.0 0.00141 161
90.0 0.00158 181
100 0.00176 201
200 0.00352 402
300 0.00528 603
400 0.00704 804
500 0.00880 1000
600 0.0106 1210
700 0.0123 1410
800 0.0141 1610
900 0.0158 1810
1000 0.0176 2010
2000 0.0352 4020
3000 0.0528 6030
4000 0.0704 8040
5000 0.0880 1.00 × 104
6000 0.106 1.21 × 104
7000 0.123 1.41 × 104
8000 0.141 1.61 × 104
9000 0.158 1.81 × 104
1.00 × 104 0.176 2.01 × 104
2.00 × 104 0.352 4.02 × 104
3.00 × 104 0.528 6.03 × 104
4.00 × 104 0.704 8.04 × 104
5.00 × 104 0.880 1.00 × 105
6.00 × 104 1.06 1.21 × 105
7.00 × 104 1.23 1.41 × 105
8.00 × 104 1.41 1.61 × 105
9.00 × 104 1.58 1.81 × 105
1.00 × 105 1.76 2.01 × 105
1.48 × 105 2.60 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.00428 275
80.0 0.00445 286
90.0 0.00500 321
100 0.00556 357
200 0.0111 714
300 0.0167 1070
400 0.0222 1430
500 0.0278 1790
600 0.0334 2140
700 0.0389 2500
800 0.0445 2860
900 0.0500 3210
1000 0.0556 3570
2000 0.111 7140
3000 0.167 1.07 × 104
4000 0.222 1.43 × 104
5000 0.278 1.79 × 104
6000 0.334 2.14 × 104
7000 0.389 2.50 × 104
8000 0.445 2.86 × 104
9000 0.500 3.21 × 104
1.00 × 104 0.556 3.57 × 104
2.00 × 104 1.11 7.14 × 104
3.00 × 104 1.67 1.07 × 105
4.00 × 104 2.22 1.43 × 105
5.00 × 104 2.78 1.79 × 105
6.00 × 104 3.34 2.14 × 105
7.00 × 104 3.89 2.50 × 105
8.00 × 104 4.45 2.86 × 105
8.32 × 104 4.62 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.0105 430
80.0 0.0109 446
90.0 0.0122 502
100 0.0136 558
200 0.0272 1120
300 0.0407 1670
400 0.0543 2230
500 0.0679 2790
600 0.0815 3350
700 0.0950 3910
800 0.109 4460
900 0.122 5020
1000 0.136 5580
2000 0.272 1.12 × 104
3000 0.407 1.67 × 104
4000 0.543 2.23 × 104
5000 0.679 2.79 × 104
6000 0.815 3.35 × 104
7000 0.950 3.91 × 104
8000 1.09 4.46 × 104
9000 1.22 5.02 × 104
1.00 × 104 1.36 5.58 × 104
2.00 × 104 2.72 1.12 × 105
3.00 × 104 4.07 1.67 × 105
4.00 × 104 5.43 2.23 × 105
5.00 × 104 6.79 2.79 × 105
5.32 × 104 7.23 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.0217 619
80.0 0.0225 643
90.0 0.0253 723
100 0.0282 804
200 0.0563 1610
300 0.0845 2410
400 0.113 3210
500 0.141 4020
600 0.169 4820
700 0.197 5630
800 0.225 6430
900 0.253 7230
1000 0.282 8040
2000 0.563 1.61 × 104
3000 0.845 2.41 × 104
4000 1.13 3.21 × 104
5000 1.41 4.02 × 104
6000 1.69 4.82 × 104
7000 1.97 5.63 × 104
8000 2.25 6.43 × 104
9000 2.53 7.23 × 104
1.00 × 104 2.82 8.04 × 104
2.00 × 104 5.63 1.61 × 105
3.00 × 104 8.45 2.41 × 105
3.70 × 104 10.4 2.97 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.0685 1100
80.0 0.0712 1140
90.0 0.0801 1290
100 0.0890 1430
200 0.178 2860
300 0.267 4290
400 0.356 5720
500 0.445 7140
600 0.534 8570
700 0.623 1.00 × 104
800 0.712 1.14 × 104
900 0.801 1.29 × 104
1000 0.890 1.43 × 104
2000 1.78 2.86 × 104
3000 2.67 4.29 × 104
4000 3.56 5.72 × 104
5000 4.45 7.14 × 104
6000 5.34 8.57 × 104
7000 6.23 1.00 × 105
8000 7.12 1.14 × 105
9000 8.01 1.29 × 105
1.00 × 104 8.90 1.43 × 105
1.86 × 104 16.5 2.65 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.167 1720
80.0 0.174 1790
90.0 0.196 2010
100 0.217 2230
200 0.434 4460
300 0.652 6700
400 0.869 8930
500 1.09 1.12 × 104
600 1.30 1.34 × 104
700 1.52 1.56 × 104
800 1.74 1.79 × 104
900 1.96 2.01 × 104
1000 2.17 2.23 × 104
2000 4.34 4.46 × 104
3000 6.52 6.70 × 104
4000 8.69 8.93 × 104
5000 10.9 1.12 × 105
6000 13.0 1.34 × 105
7000 15.2 1.56 × 105
7610 16.5 1.70 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 60.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.347 2480
80.0 0.360 2570
90.0 0.405 2890
100 0.450 3210
200 0.901 6430
300 1.35 9640
400 1.80 1.29 × 104
500 2.25 1.61 × 104
600 2.70 1.93 × 104
700 3.15 2.25 × 104
800 3.60 2.57 × 104
900 4.05 2.89 × 104
1000 4.50 3.21 × 104
2000 9.01 6.43 × 104
3000 13.5 9.64 × 104
3670 16.5 1.18 × 105
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 70.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 0.643 3370
80.0 0.668 3500
90.0 0.751 3940
100 0.834 4380
200 1.67 8750
300 2.50 1.31 × 104
400 3.34 1.75 × 104
500 4.17 2.19 × 104
600 5.01 2.63 × 104
700 5.84 3.06 × 104
800 6.68 3.50 × 104
900 7.51 3.94 × 104
1000 8.34 4.38 × 104
1980 16.5 8.66 × 104
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 80.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 1.10 4400
80.0 1.14 4570
90.0 1.28 5140
100 1.42 5720
200 2.85 1.14 × 104
300 4.27 1.71 × 104
400 5.69 2.29 × 104
500 7.12 2.86 × 104
600 8.54 3.43 × 104
700 9.97 4.00 × 104
800 11.4 4.57 × 104
900 12.8 5.14 × 104
1000 14.2 5.72 × 104
1160 16.5 6.63 × 104
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 90.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 1.76 5570
80.0 1.82 5790
90.0 2.05 6510
100 2.28 7230
200 4.56 1.45 × 104
300 6.84 2.17 × 104
400 9.12 2.89 × 104
500 11.4 3.62 × 104
600 13.7 4.34 × 104
700 16.0 5.06 × 104
724 16.5 5.24 × 104
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 100 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 2.68 6880
80.0 2.78 7140
90.0 3.13 8040
100 3.48 8930
200 6.95 1.79 × 104
300 10.4 2.68 × 104
400 13.9 3.57 × 104
475 16.5 4.24 × 104
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 125 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 6.53 1.07 × 104
80.0 6.79 1.12 × 104
90.0 7.64 1.26 × 104
100 8.49 1.40 × 104
195 16.5 2.72 × 104
Steel I Beam: W16 × 77 (Wide Flange 16 inch tall × 77 lbf/ft)
L = 150 ft
P (lbf/ft) w_max (in) stress_max (psi)
77.0 13.5 1.55 × 104
80.0 14.1 1.61 × 104
90.0 15.8 1.81 × 104
93.9 16.5 1.89 × 104
Additional Information
Related Pages
FREE Publications
CNC Machining Design Guide

Optimize your designs, reduce machining time, and lower your costs.

STEM Career Outlook

Wages, employment opportunities, and growth projections for STEM jobs.

3D Scanners

A white paper to assist in the evaluation of 3D scanning hardware solutions.

Negotiate Your Salary

Learn the best principles to negotiate the salary you deserve!

more publications