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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Four Equal Spans » Wide Flange Steel I Beam » W12 × 30
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 stress_max 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 = 238 in4) for the W12 × 30 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: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 3.65 × 10-6 9.00
40.0 4.87 × 10-6 12.0
50.0 6.08 × 10-6 15.0
60.0 7.30 × 10-6 18.0
70.0 8.52 × 10-6 21.0
80.0 9.73 × 10-6 24.0
90.0 1.09 × 10-5 27.0
100 1.22 × 10-5 30.0
200 2.43 × 10-5 60.0
300 3.65 × 10-5 90.0
400 4.87 × 10-5 120
500 6.08 × 10-5 150
600 7.30 × 10-5 180
700 8.52 × 10-5 210
800 9.73 × 10-5 240
900 1.09 × 10-4 270
1000 1.22 × 10-4 300
2000 2.43 × 10-4 600
3000 3.65 × 10-4 900
4000 4.87 × 10-4 1200
5000 6.08 × 10-4 1500
6000 7.30 × 10-4 1800
7000 8.52 × 10-4 2100
8000 9.73 × 10-4 2400
9000 0.00109 2700
1.00 × 104 0.00122 3000
2.00 × 104 0.00243 6000
3.00 × 104 0.00365 9000
4.00 × 104 0.00487 1.20 × 104
5.00 × 104 0.00608 1.50 × 104
6.00 × 104 0.00730 1.80 × 104
7.00 × 104 0.00852 2.10 × 104
8.00 × 104 0.00973 2.40 × 104
9.00 × 104 0.0109 2.70 × 104
1.00 × 105 0.0122 3.00 × 104
2.00 × 105 0.0243 6.00 × 104
3.00 × 105 0.0365 9.00 × 104
4.00 × 105 0.0487 1.20 × 105
5.00 × 105 0.0608 1.50 × 105
6.00 × 105 0.0730 1.80 × 105
7.00 × 105 0.0852 2.10 × 105
8.00 × 105 0.0973 2.40 × 105
9.00 × 105 0.109 2.70 × 105
9.91 × 105 0.120 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 2.82 × 10-5 25.0
40.0 3.75 × 10-5 33.3
50.0 4.69 × 10-5 41.6
60.0 5.63 × 10-5 50.0
70.0 6.57 × 10-5 58.3
80.0 7.51 × 10-5 66.6
90.0 8.45 × 10-5 75.0
100 9.39 × 10-5 83.3
200 1.88 × 10-4 167
300 2.82 × 10-4 250
400 3.75 × 10-4 333
500 4.69 × 10-4 416
600 5.63 × 10-4 500
700 6.57 × 10-4 583
800 7.51 × 10-4 666
900 8.45 × 10-4 750
1000 9.39 × 10-4 833
2000 0.00188 1670
3000 0.00282 2500
4000 0.00375 3330
5000 0.00469 4160
6000 0.00563 5000
7000 0.00657 5830
8000 0.00751 6660
9000 0.00845 7500
1.00 × 104 0.00939 8330
2.00 × 104 0.0188 1.67 × 104
3.00 × 104 0.0282 2.50 × 104
4.00 × 104 0.0375 3.33 × 104
5.00 × 104 0.0469 4.16 × 104
6.00 × 104 0.0563 5.00 × 104
7.00 × 104 0.0657 5.83 × 104
8.00 × 104 0.0751 6.66 × 104
9.00 × 104 0.0845 7.50 × 104
1.00 × 105 0.0939 8.33 × 104
2.00 × 105 0.188 1.67 × 105
3.00 × 105 0.282 2.50 × 105
3.57 × 105 0.335 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 4.51 × 10-4 100
40.0 6.01 × 10-4 133
50.0 7.51 × 10-4 167
60.0 9.01 × 10-4 200
70.0 0.00105 233
80.0 0.00120 267
90.0 0.00135 300
100 0.00150 333
200 0.00300 666
300 0.00451 1000
400 0.00601 1330
500 0.00751 1670
600 0.00901 2000
700 0.0105 2330
800 0.0120 2670
900 0.0135 3000
1000 0.0150 3330
2000 0.0300 6660
3000 0.0451 10000
4000 0.0601 1.33 × 104
5000 0.0751 1.67 × 104
6000 0.0901 2.00 × 104
7000 0.105 2.33 × 104
8000 0.120 2.67 × 104
9000 0.135 3.00 × 104
1.00 × 104 0.150 3.33 × 104
2.00 × 104 0.300 6.66 × 104
3.00 × 104 0.451 1.00 × 105
4.00 × 104 0.601 1.33 × 105
5.00 × 104 0.751 1.67 × 105
6.00 × 104 0.901 2.00 × 105
7.00 × 104 1.05 2.33 × 105
8.00 × 104 1.20 2.67 × 105
8.92 × 104 1.34 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.00228 225
40.0 0.00304 300
50.0 0.00380 375
60.0 0.00456 450
70.0 0.00532 525
80.0 0.00608 600
90.0 0.00684 675
100 0.00760 750
200 0.0152 1500
300 0.0228 2250
400 0.0304 3000
500 0.0380 3750
600 0.0456 4500
700 0.0532 5250
800 0.0608 6000
900 0.0684 6750
1000 0.0760 7500
2000 0.152 1.50 × 104
3000 0.228 2.25 × 104
4000 0.304 3.00 × 104
5000 0.380 3.75 × 104
6000 0.456 4.50 × 104
7000 0.532 5.25 × 104
8000 0.608 6.00 × 104
9000 0.684 6.75 × 104
1.00 × 104 0.760 7.50 × 104
2.00 × 104 1.52 1.50 × 105
3.00 × 104 2.28 2.25 × 105
3.96 × 104 3.01 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.00721 400
40.0 0.00961 533
50.0 0.0120 666
60.0 0.0144 800
70.0 0.0168 933
80.0 0.0192 1070
90.0 0.0216 1200
100 0.0240 1330
200 0.0481 2670
300 0.0721 4000
400 0.0961 5330
500 0.120 6660
600 0.144 8000
700 0.168 9330
800 0.192 1.07 × 104
900 0.216 1.20 × 104
1000 0.240 1.33 × 104
2000 0.481 2.67 × 104
3000 0.721 4.00 × 104
4000 0.961 5.33 × 104
5000 1.20 6.66 × 104
6000 1.44 8.00 × 104
7000 1.68 9.33 × 104
8000 1.92 1.07 × 105
9000 2.16 1.20 × 105
1.00 × 104 2.40 1.33 × 105
2.00 × 104 4.81 2.67 × 105
2.23 × 104 5.36 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.0176 625
40.0 0.0235 833
50.0 0.0293 1040
60.0 0.0352 1250
70.0 0.0411 1460
80.0 0.0469 1670
90.0 0.0528 1870
100 0.0587 2080
200 0.117 4160
300 0.176 6250
400 0.235 8330
500 0.293 1.04 × 104
600 0.352 1.25 × 104
700 0.411 1.46 × 104
800 0.469 1.67 × 104
900 0.528 1.87 × 104
1000 0.587 2.08 × 104
2000 1.17 4.16 × 104
3000 1.76 6.25 × 104
4000 2.35 8.33 × 104
5000 2.93 1.04 × 105
6000 3.52 1.25 × 105
7000 4.11 1.46 × 105
8000 4.69 1.67 × 105
9000 5.28 1.87 × 105
1.00 × 104 5.87 2.08 × 105
1.43 × 104 8.37 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.0365 900
40.0 0.0487 1200
50.0 0.0608 1500
60.0 0.0730 1800
70.0 0.0852 2100
80.0 0.0973 2400
90.0 0.109 2700
100 0.122 3000
200 0.243 6000
300 0.365 9000
400 0.487 1.20 × 104
500 0.608 1.50 × 104
600 0.730 1.80 × 104
700 0.852 2.10 × 104
800 0.973 2.40 × 104
900 1.09 2.70 × 104
1000 1.22 3.00 × 104
2000 2.43 6.00 × 104
3000 3.65 9.00 × 104
4000 4.87 1.20 × 105
5000 6.08 1.50 × 105
6000 7.30 1.80 × 105
7000 8.52 2.10 × 105
8000 9.73 2.40 × 105
9000 10.9 2.70 × 105
9910 12.0 2.97 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.115 1600
40.0 0.154 2130
50.0 0.192 2670
60.0 0.231 3200
70.0 0.269 3730
80.0 0.308 4260
90.0 0.346 4800
100 0.384 5330
200 0.769 1.07 × 104
300 1.15 1.60 × 104
400 1.54 2.13 × 104
500 1.92 2.67 × 104
600 2.31 3.20 × 104
700 2.69 3.73 × 104
800 3.08 4.26 × 104
900 3.46 4.80 × 104
1000 3.84 5.33 × 104
2000 7.69 1.07 × 105
3000 11.5 1.60 × 105
3210 12.3 1.71 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.282 2500
40.0 0.375 3330
50.0 0.469 4160
60.0 0.563 5000
70.0 0.657 5830
80.0 0.751 6660
90.0 0.845 7500
100 0.939 8330
200 1.88 1.67 × 104
300 2.82 2.50 × 104
400 3.75 3.33 × 104
500 4.69 4.16 × 104
600 5.63 5.00 × 104
700 6.57 5.83 × 104
800 7.51 6.66 × 104
900 8.45 7.50 × 104
1000 9.39 8.33 × 104
1310 12.3 1.10 × 105
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 60.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 0.584 3600
40.0 0.779 4800
50.0 0.973 6000
60.0 1.17 7200
70.0 1.36 8400
80.0 1.56 9600
90.0 1.75 1.08 × 104
100 1.95 1.20 × 104
200 3.89 2.40 × 104
300 5.84 3.60 × 104
400 7.79 4.80 × 104
500 9.73 6.00 × 104
600 11.7 7.20 × 104
634 12.3 7.60 × 104
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 70.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 1.08 4900
40.0 1.44 6530
50.0 1.80 8160
60.0 2.16 9800
70.0 2.52 1.14 × 104
80.0 2.88 1.31 × 104
90.0 3.25 1.47 × 104
100 3.61 1.63 × 104
200 7.21 3.27 × 104
300 10.8 4.90 × 104
342 12.3 5.59 × 104
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 80.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 1.85 6400
40.0 2.46 8530
50.0 3.08 1.07 × 104
60.0 3.69 1.28 × 104
70.0 4.31 1.49 × 104
80.0 4.92 1.71 × 104
90.0 5.54 1.92 × 104
100 6.15 2.13 × 104
200 12.3 4.26 × 104
201 12.3 4.28 × 104
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 90.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 2.96 8100
40.0 3.94 1.08 × 104
50.0 4.93 1.35 × 104
60.0 5.91 1.62 × 104
70.0 6.90 1.89 × 104
80.0 7.88 2.16 × 104
90.0 8.87 2.43 × 104
100 9.85 2.70 × 104
125 12.3 3.38 × 104
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 100 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 4.51 10000
40.0 6.01 1.33 × 104
50.0 7.51 1.67 × 104
60.0 9.01 2.00 × 104
70.0 10.5 2.33 × 104
80.0 12.0 2.67 × 104
82.2 12.3 2.74 × 104
Steel I Beam: W12 × 30 (Wide Flange 12 inch tall × 30 lbf/ft)
L = 125 ft
P (lbf/ft) w_max (in) stress_max (psi)
30.0 11.0 1.56 × 104
33.7 12.3 1.75 × 104
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Injection Molding Design Guide

Guide for high quality and cost-effective plastic injection molding.

Mechanical Engineers Outlook

Guide for those interested in becoming a mechanical engineer. Includes qualifications, pay, and job duties.

Negotiate Your Salary

Learn the best principles to negotiate the salary you deserve!

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

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