Materials Design Center Processes Unit Conversion Formulas Mathematics
 Calculators Discussion Forum Trade Publications Directory Service
Reinforced Plastics

Informed and impartial coverage on the global composites industry.

CNC Machining Design Guide

Autonomous Vehicle Engineering

The No. 1 media source for those developing the next generation mobility solutions.

Laser Solutions

Cost-effective laser solutions for many manufacturing problems.

more free magazines
Glossary » Beams » Simply Supported » Uniformly Distributed Load » Three Equal Spans » Wide Flange Steel I Beam » W8 × 31
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 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 = 110 in4) for the W8 × 31 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: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 3.00 ft (lbf/ft) (in) (psi) 31.0 8.81 × 10-6 12.2 40.0 1.14 × 10-5 15.7 50.0 1.42 × 10-5 19.6 60.0 1.70 × 10-5 23.6 70.0 1.99 × 10-5 27.5 80.0 2.27 × 10-5 31.4 90.0 2.56 × 10-5 35.3 100 2.84 × 10-5 39.3 200 5.68 × 10-5 78.5 300 8.52 × 10-5 118 400 1.14 × 10-4 157 500 1.42 × 10-4 196 600 1.70 × 10-4 236 700 1.99 × 10-4 275 800 2.27 × 10-4 314 900 2.56 × 10-4 353 1000 2.84 × 10-4 393 2000 5.68 × 10-4 785 3000 8.52 × 10-4 1180 4000 0.00114 1570 5000 0.00142 1960 6000 0.00170 2360 7000 0.00199 2750 8000 0.00227 3140 9000 0.00256 3530 1.00 × 104 0.00284 3930 2.00 × 104 0.00568 7850 3.00 × 104 0.00852 1.18 × 104 4.00 × 104 0.0114 1.57 × 104 5.00 × 104 0.0142 1.96 × 104 6.00 × 104 0.0170 2.36 × 104 7.00 × 104 0.0199 2.75 × 104 8.00 × 104 0.0227 3.14 × 104 9.00 × 104 0.0256 3.53 × 104 1.00 × 105 0.0284 3.93 × 104 2.00 × 105 0.0568 7.85 × 104 3.00 × 105 0.0852 1.18 × 105 4.00 × 105 0.114 1.57 × 105 5.00 × 105 0.142 1.96 × 105 6.00 × 105 0.170 2.36 × 105 7.00 × 105 0.199 2.75 × 105 7.56 × 105 0.215 2.97 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 5.00 ft (lbf/ft) (in) (psi) 31.0 6.80 × 10-5 33.8 40.0 8.77 × 10-5 43.6 50.0 1.10 × 10-4 54.5 60.0 1.32 × 10-4 65.5 70.0 1.53 × 10-4 76.4 80.0 1.75 × 10-4 87.3 90.0 1.97 × 10-4 98.2 100 2.19 × 10-4 109 200 4.38 × 10-4 218 300 6.58 × 10-4 327 400 8.77 × 10-4 436 500 0.00110 545 600 0.00132 655 700 0.00153 764 800 0.00175 873 900 0.00197 982 1000 0.00219 1090 2000 0.00438 2180 3000 0.00658 3270 4000 0.00877 4360 5000 0.0110 5450 6000 0.0132 6550 7000 0.0153 7640 8000 0.0175 8730 9000 0.0197 9820 1.00 × 104 0.0219 1.09 × 104 2.00 × 104 0.0438 2.18 × 104 3.00 × 104 0.0658 3.27 × 104 4.00 × 104 0.0877 4.36 × 104 5.00 × 104 0.110 5.45 × 104 6.00 × 104 0.132 6.55 × 104 7.00 × 104 0.153 7.64 × 104 8.00 × 104 0.175 8.73 × 104 9.00 × 104 0.197 9.82 × 104 1.00 × 105 0.219 1.09 × 105 2.00 × 105 0.438 2.18 × 105 2.72 × 105 0.597 2.97 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 10.0 ft (lbf/ft) (in) (psi) 31.0 0.00109 135 40.0 0.00140 175 50.0 0.00175 218 60.0 0.00210 262 70.0 0.00246 305 80.0 0.00281 349 90.0 0.00316 393 100 0.00351 436 200 0.00701 873 300 0.0105 1310 400 0.0140 1750 500 0.0175 2180 600 0.0210 2620 700 0.0246 3050 800 0.0281 3490 900 0.0316 3930 1000 0.0351 4360 2000 0.0701 8730 3000 0.105 1.31 × 104 4000 0.140 1.75 × 104 5000 0.175 2.18 × 104 6000 0.210 2.62 × 104 7000 0.246 3.05 × 104 8000 0.281 3.49 × 104 9000 0.316 3.93 × 104 1.00 × 104 0.351 4.36 × 104 2.00 × 104 0.701 8.73 × 104 3.00 × 104 1.05 1.31 × 105 4.00 × 104 1.40 1.75 × 105 5.00 × 104 1.75 2.18 × 105 6.00 × 104 2.10 2.62 × 105 6.81 × 104 2.39 2.97 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 15.0 ft (lbf/ft) (in) (psi) 31.0 0.00550 304 40.0 0.00710 393 50.0 0.00888 491 60.0 0.0107 589 70.0 0.0124 687 80.0 0.0142 785 90.0 0.0160 884 100 0.0178 982 200 0.0355 1960 300 0.0533 2950 400 0.0710 3930 500 0.0888 4910 600 0.107 5890 700 0.124 6870 800 0.142 7850 900 0.160 8840 1000 0.178 9820 2000 0.355 1.96 × 104 3000 0.533 2.95 × 104 4000 0.710 3.93 × 104 5000 0.888 4.91 × 104 6000 1.07 5.89 × 104 7000 1.24 6.87 × 104 8000 1.42 7.85 × 104 9000 1.60 8.84 × 104 1.00 × 104 1.78 9.82 × 104 2.00 × 104 3.55 1.96 × 105 3.00 × 104 5.33 2.95 × 105 3.03 × 104 5.37 2.97 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 20.0 ft (lbf/ft) (in) (psi) 31.0 0.0174 541 40.0 0.0224 698 50.0 0.0281 873 60.0 0.0337 1050 70.0 0.0393 1220 80.0 0.0449 1400 90.0 0.0505 1570 100 0.0561 1750 200 0.112 3490 300 0.168 5240 400 0.224 6980 500 0.281 8730 600 0.337 1.05 × 104 700 0.393 1.22 × 104 800 0.449 1.40 × 104 900 0.505 1.57 × 104 1000 0.561 1.75 × 104 2000 1.12 3.49 × 104 3000 1.68 5.24 × 104 4000 2.24 6.98 × 104 5000 2.81 8.73 × 104 6000 3.37 1.05 × 105 7000 3.93 1.22 × 105 8000 4.49 1.40 × 105 9000 5.05 1.57 × 105 1.00 × 104 5.61 1.75 × 105 1.70 × 104 9.55 2.97 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 25.0 ft (lbf/ft) (in) (psi) 31.0 0.0425 845 40.0 0.0548 1090 50.0 0.0685 1360 60.0 0.0822 1640 70.0 0.0959 1910 80.0 0.110 2180 90.0 0.123 2450 100 0.137 2730 200 0.274 5450 300 0.411 8180 400 0.548 1.09 × 104 500 0.685 1.36 × 104 600 0.822 1.64 × 104 700 0.959 1.91 × 104 800 1.10 2.18 × 104 900 1.23 2.45 × 104 1000 1.37 2.73 × 104 2000 2.74 5.45 × 104 3000 4.11 8.18 × 104 4000 5.48 1.09 × 105 5000 6.85 1.36 × 105 5840 8.00 1.59 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 30.0 ft (lbf/ft) (in) (psi) 31.0 0.0881 1220 40.0 0.114 1570 50.0 0.142 1960 60.0 0.170 2360 70.0 0.199 2750 80.0 0.227 3140 90.0 0.256 3530 100 0.284 3930 200 0.568 7850 300 0.852 1.18 × 104 400 1.14 1.57 × 104 500 1.42 1.96 × 104 600 1.70 2.36 × 104 700 1.99 2.75 × 104 800 2.27 3.14 × 104 900 2.56 3.53 × 104 1000 2.84 3.93 × 104 2000 5.68 7.85 × 104 2820 8.00 1.11 × 105
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 40.0 ft (lbf/ft) (in) (psi) 31.0 0.278 2160 40.0 0.359 2790 50.0 0.449 3490 60.0 0.539 4190 70.0 0.628 4890 80.0 0.718 5590 90.0 0.808 6280 100 0.898 6980 200 1.80 1.40 × 104 300 2.69 2.09 × 104 400 3.59 2.79 × 104 500 4.49 3.49 × 104 600 5.39 4.19 × 104 700 6.28 4.89 × 104 800 7.18 5.59 × 104 891 8.00 6.22 × 104
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 50.0 ft (lbf/ft) (in) (psi) 31.0 0.680 3380 40.0 0.877 4360 50.0 1.10 5450 60.0 1.32 6550 70.0 1.53 7640 80.0 1.75 8730 90.0 1.97 9820 100 2.19 1.09 × 104 200 4.38 2.18 × 104 300 6.58 3.27 × 104 365 8.00 3.98 × 104
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 60.0 ft (lbf/ft) (in) (psi) 31.0 1.41 4870 40.0 1.82 6280 50.0 2.27 7850 60.0 2.73 9430 70.0 3.18 1.10 × 104 80.0 3.64 1.26 × 104 90.0 4.09 1.41 × 104 100 4.55 1.57 × 104 176 8.00 2.76 × 104
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 70.0 ft (lbf/ft) (in) (psi) 31.0 2.61 6630 40.0 3.37 8550 50.0 4.21 1.07 × 104 60.0 5.05 1.28 × 104 70.0 5.89 1.50 × 104 80.0 6.74 1.71 × 104 90.0 7.58 1.92 × 104 95.0 8.00 2.03 × 104
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 80.0 ft (lbf/ft) (in) (psi) 31.0 4.45 8660 40.0 5.75 1.12 × 104 50.0 7.18 1.40 × 104 55.7 8.00 1.56 × 104
 Steel I Beam: W8 × 31 (Wide Flange 8 inch tall × 31 lbf/ft) L = 90.0 ft (lbf/ft) (in) (psi) 31.0 7.13 1.10 × 104 34.8 8.00 1.23 × 104