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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Single Span » S Section Steel I Beam » S4 × 7.7
S Section 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 = 6.08 in4) for the S4 × 7.7 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: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 7.58 × 10-5 34.2
8.00 7.87 × 10-5 35.5
9.00 8.86 × 10-5 40.0
10.0 9.84 × 10-5 44.4
20.0 1.97 × 10-4 88.8
30.0 2.95 × 10-4 133
40.0 3.94 × 10-4 178
50.0 4.92 × 10-4 222
60.0 5.90 × 10-4 266
70.0 6.89 × 10-4 311
80.0 7.87 × 10-4 355
90.0 8.86 × 10-4 400
100 9.84 × 10-4 444
200 0.00197 888
300 0.00295 1330
400 0.00394 1780
500 0.00492 2220
600 0.00590 2660
700 0.00689 3110
800 0.00787 3550
900 0.00886 4000
1000 0.00984 4440
2000 0.0197 8880
3000 0.0295 1.33 × 104
4000 0.0394 1.78 × 104
5000 0.0492 2.22 × 104
6000 0.0590 2.66 × 104
7000 0.0689 3.11 × 104
8000 0.0787 3.55 × 104
9000 0.0886 4.00 × 104
1.00 × 104 0.0984 4.44 × 104
2.00 × 104 0.197 8.88 × 104
3.00 × 104 0.295 1.33 × 105
4.00 × 104 0.394 1.78 × 105
5.00 × 104 0.492 2.22 × 105
6.00 × 104 0.590 2.66 × 105
6.69 × 104 0.658 2.97 × 105
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 5.85 × 10-4 95.0
8.00 6.08 × 10-4 98.7
9.00 6.83 × 10-4 111
10.0 7.59 × 10-4 123
20.0 0.00152 247
30.0 0.00228 370
40.0 0.00304 493
50.0 0.00380 617
60.0 0.00456 740
70.0 0.00532 863
80.0 0.00608 987
90.0 0.00683 1110
100 0.00759 1230
200 0.0152 2470
300 0.0228 3700
400 0.0304 4930
500 0.0380 6170
600 0.0456 7400
700 0.0532 8630
800 0.0608 9870
900 0.0683 1.11 × 104
1000 0.0759 1.23 × 104
2000 0.152 2.47 × 104
3000 0.228 3.70 × 104
4000 0.304 4.93 × 104
5000 0.380 6.17 × 104
6000 0.456 7.40 × 104
7000 0.532 8.63 × 104
8000 0.608 9.87 × 104
9000 0.683 1.11 × 105
1.00 × 104 0.759 1.23 × 105
2.00 × 104 1.52 2.47 × 105
2.41 × 104 1.83 2.97 × 105
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 0.00936 380
8.00 0.00972 395
9.00 0.0109 444
10.0 0.0122 493
20.0 0.0243 987
30.0 0.0365 1480
40.0 0.0486 1970
50.0 0.0608 2470
60.0 0.0729 2960
70.0 0.0851 3450
80.0 0.0972 3950
90.0 0.109 4440
100 0.122 4930
200 0.243 9870
300 0.365 1.48 × 104
400 0.486 1.97 × 104
500 0.608 2.47 × 104
600 0.729 2.96 × 104
700 0.851 3.45 × 104
800 0.972 3.95 × 104
900 1.09 4.44 × 104
1000 1.22 4.93 × 104
2000 2.43 9.87 × 104
3000 3.65 1.48 × 105
3290 4.00 1.62 × 105
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 0.0474 855
8.00 0.0492 888
9.00 0.0554 999
10.0 0.0615 1110
20.0 0.123 2220
30.0 0.185 3330
40.0 0.246 4440
50.0 0.308 5550
60.0 0.369 6660
70.0 0.431 7770
80.0 0.492 8880
90.0 0.554 9990
100 0.615 1.11 × 104
200 1.23 2.22 × 104
300 1.85 3.33 × 104
400 2.46 4.44 × 104
500 3.08 5.55 × 104
600 3.69 6.66 × 104
650 4.00 7.22 × 104
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 0.150 1520
8.00 0.156 1580
9.00 0.175 1780
10.0 0.194 1970
20.0 0.389 3950
30.0 0.583 5920
40.0 0.778 7890
50.0 0.972 9870
60.0 1.17 1.18 × 104
70.0 1.36 1.38 × 104
80.0 1.56 1.58 × 104
90.0 1.75 1.78 × 104
100 1.94 1.97 × 104
200 3.89 3.95 × 104
206 4.00 4.06 × 104
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 0.365 2370
8.00 0.380 2470
9.00 0.427 2780
10.0 0.475 3080
20.0 0.949 6170
30.0 1.42 9250
40.0 1.90 1.23 × 104
50.0 2.37 1.54 × 104
60.0 2.85 1.85 × 104
70.0 3.32 2.16 × 104
80.0 3.80 2.47 × 104
84.3 4.00 2.60 × 104
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 0.758 3420
8.00 0.787 3550
9.00 0.886 4000
10.0 0.984 4440
20.0 1.97 8880
30.0 2.95 1.33 × 104
40.0 3.94 1.78 × 104
40.6 4.00 1.80 × 104
Steel I Beam: S4 × 7.7 (S Section 4 inch tall × 7.7 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
7.70 2.40 6080
8.00 2.49 6320
9.00 2.80 7110
10.0 3.11 7890
12.9 4.00 1.02 × 104
Additional Information
Related Pages
Glossary
Selecting the Right 3D Printer

Discover how to choose the right 3D printer for your needs and the key performance attributes to consider.

Injection Molding Design Guide

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

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.