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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Four Equal Spans » S Section Steel I Beam » S3 × 7.5
S Section 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 = 2.93 in4) for the S3 × 7.5 S Section 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
   
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 7.41 × 10-5 44.4
8.00 7.90 × 10-5 47.4
9.00 8.89 × 10-5 53.3
10.0 9.88 × 10-5 59.2
20.0 1.98 × 10-4 118
30.0 2.96 × 10-4 178
40.0 3.95 × 10-4 237
50.0 4.94 × 10-4 296
60.0 5.93 × 10-4 355
70.0 6.92 × 10-4 415
80.0 7.90 × 10-4 474
90.0 8.89 × 10-4 533
100 9.88 × 10-4 592
200 0.00198 1180
300 0.00296 1780
400 0.00395 2370
500 0.00494 2960
600 0.00593 3550
700 0.00692 4150
800 0.00790 4740
900 0.00889 5330
1000 0.00988 5920
2000 0.0198 1.18 × 104
3000 0.0296 1.78 × 104
4000 0.0395 2.37 × 104
5000 0.0494 2.96 × 104
6000 0.0593 3.55 × 104
7000 0.0692 4.15 × 104
8000 0.0790 4.74 × 104
9000 0.0889 5.33 × 104
1.00 × 104 0.0988 5.92 × 104
2.00 × 104 0.198 1.18 × 105
3.00 × 104 0.296 1.78 × 105
4.00 × 104 0.395 2.37 × 105
5.00 × 104 0.494 2.96 × 105
5.02 × 104 0.496 2.97 × 105
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 5.72 × 10-4 123
8.00 6.10 × 10-4 132
9.00 6.86 × 10-4 148
10.0 7.62 × 10-4 164
20.0 0.00152 329
30.0 0.00229 493
40.0 0.00305 658
50.0 0.00381 822
60.0 0.00457 987
70.0 0.00534 1150
80.0 0.00610 1320
90.0 0.00686 1480
100 0.00762 1640
200 0.0152 3290
300 0.0229 4930
400 0.0305 6580
500 0.0381 8220
600 0.0457 9870
700 0.0534 1.15 × 104
800 0.0610 1.32 × 104
900 0.0686 1.48 × 104
1000 0.0762 1.64 × 104
2000 0.152 3.29 × 104
3000 0.229 4.93 × 104
4000 0.305 6.58 × 104
5000 0.381 8.22 × 104
6000 0.457 9.87 × 104
7000 0.534 1.15 × 105
8000 0.610 1.32 × 105
9000 0.686 1.48 × 105
1.00 × 104 0.762 1.64 × 105
1.81 × 104 1.38 2.97 × 105
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 0.00915 493
8.00 0.00976 526
9.00 0.0110 592
10.0 0.0122 658
20.0 0.0244 1320
30.0 0.0366 1970
40.0 0.0488 2630
50.0 0.0610 3290
60.0 0.0732 3950
70.0 0.0854 4610
80.0 0.0976 5260
90.0 0.110 5920
100 0.122 6580
200 0.244 1.32 × 104
300 0.366 1.97 × 104
400 0.488 2.63 × 104
500 0.610 3.29 × 104
600 0.732 3.95 × 104
700 0.854 4.61 × 104
800 0.976 5.26 × 104
900 1.10 5.92 × 104
1000 1.22 6.58 × 104
2000 2.44 1.32 × 105
2460 3.00 1.62 × 105
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 0.0463 1110
8.00 0.0494 1180
9.00 0.0556 1330
10.0 0.0618 1480
20.0 0.124 2960
30.0 0.185 4440
40.0 0.247 5920
50.0 0.309 7400
60.0 0.371 8880
70.0 0.432 1.04 × 104
80.0 0.494 1.18 × 104
90.0 0.556 1.33 × 104
100 0.618 1.48 × 104
200 1.24 2.96 × 104
300 1.85 4.44 × 104
400 2.47 5.92 × 104
486 3.00 7.19 × 104
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 0.146 1970
8.00 0.156 2110
9.00 0.176 2370
10.0 0.195 2630
20.0 0.390 5260
30.0 0.586 7900
40.0 0.781 1.05 × 104
50.0 0.976 1.32 × 104
60.0 1.17 1.58 × 104
70.0 1.37 1.84 × 104
80.0 1.56 2.11 × 104
90.0 1.76 2.37 × 104
100 1.95 2.63 × 104
154 3.00 4.05 × 104
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 0.357 3080
8.00 0.381 3290
9.00 0.429 3700
10.0 0.477 4110
20.0 0.953 8220
30.0 1.43 1.23 × 104
40.0 1.91 1.64 × 104
50.0 2.38 2.06 × 104
60.0 2.86 2.47 × 104
63.0 3.00 2.59 × 104
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 0.741 4440
8.00 0.790 4740
9.00 0.889 5330
10.0 0.988 5920
20.0 1.98 1.18 × 104
30.0 2.96 1.78 × 104
30.4 3.00 1.80 × 104
Steel I Beam: S3 × 7.5 (S3 inch tall × 7.5 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.50 2.34 7900
8.00 2.50 8420
9.00 2.81 9470
9.61 3.00 1.01 × 104
Additional Information
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Negotiate Your Salary

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CNC Machining Design Guide

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

Metal 3D Printing Design Guide

Direct Metal Laser Sintering (DMLS) 3D printing for parts with reduced cost and little waste.

3D Scanners

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

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