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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Two Equal Spans » Aluminum I Beam » 4.00 × 2.311
Aluminum I Beam | Single Span | Two Equal Spans | Three Equal Spans | Four Equal Spans

For a simply supported beam in two equal spans, we compute the displacement at the middle of each span w_mid and the maximum normal stress stress_max occuring at the center support of the beam.
The tabulated data listed in this page are calculated based on the area moment of inertia (Ixx = 5.62 in4) for the 4.00 × 2.311 Aluminum I Beam and the typical Young's modulus (E = 1.015 × 107 psi) of aluminum alloys. Note that the typical yielding stress Yield of aluminum alloys can range from 4061 to 7.614 × 104 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
   
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 2.95 × 10-5 11.1
3.00 3.83 × 10-5 14.4
4.00 5.11 × 10-5 19.2
5.00 6.39 × 10-5 24.0
6.00 7.67 × 10-5 28.8
7.00 8.94 × 10-5 33.6
8.00 1.02 × 10-4 38.4
9.00 1.15 × 10-4 43.2
10.0 1.28 × 10-4 48.0
20.0 2.56 × 10-4 96.1
30.0 3.83 × 10-4 144
40.0 5.11 × 10-4 192
50.0 6.39 × 10-4 240
60.0 7.67 × 10-4 288
70.0 8.94 × 10-4 336
80.0 0.00102 384
90.0 0.00115 432
100 0.00128 480
200 0.00256 961
300 0.00383 1440
400 0.00511 1920
500 0.00639 2400
600 0.00767 2880
700 0.00894 3360
800 0.0102 3840
900 0.0115 4320
1000 0.0128 4800
2000 0.0256 9610
3000 0.0383 1.44 × 104
4000 0.0511 1.92 × 104
5000 0.0639 2.40 × 104
6000 0.0767 2.88 × 104
7000 0.0894 3.36 × 104
8000 0.102 3.84 × 104
9000 0.115 4.32 × 104
1.00 × 104 0.128 4.80 × 104
1.58 × 104 0.202 7.61 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 2.28 × 10-4 30.8
3.00 2.96 × 10-4 40.0
4.00 3.94 × 10-4 53.4
5.00 4.93 × 10-4 66.7
6.00 5.92 × 10-4 80.1
7.00 6.90 × 10-4 93.4
8.00 7.89 × 10-4 107
9.00 8.87 × 10-4 120
10.0 9.86 × 10-4 133
20.0 0.00197 267
30.0 0.00296 400
40.0 0.00394 534
50.0 0.00493 667
60.0 0.00592 801
70.0 0.00690 934
80.0 0.00789 1070
90.0 0.00887 1200
100 0.00986 1330
200 0.0197 2670
300 0.0296 4000
400 0.0394 5340
500 0.0493 6670
600 0.0592 8010
700 0.0690 9340
800 0.0789 1.07 × 104
900 0.0887 1.20 × 104
1000 0.0986 1.33 × 104
2000 0.197 2.67 × 104
3000 0.296 4.00 × 104
4000 0.394 5.34 × 104
5000 0.493 6.67 × 104
5710 0.563 7.61 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 0.00365 123
3.00 0.00473 160
4.00 0.00631 214
5.00 0.00789 267
6.00 0.00946 320
7.00 0.0110 374
8.00 0.0126 427
9.00 0.0142 480
10.0 0.0158 534
20.0 0.0315 1070
30.0 0.0473 1600
40.0 0.0631 2140
50.0 0.0789 2670
60.0 0.0946 3200
70.0 0.110 3740
80.0 0.126 4270
90.0 0.142 4800
100 0.158 5340
200 0.315 1.07 × 104
300 0.473 1.60 × 104
400 0.631 2.14 × 104
500 0.789 2.67 × 104
600 0.946 3.20 × 104
700 1.10 3.74 × 104
800 1.26 4.27 × 104
900 1.42 4.80 × 104
1000 1.58 5.34 × 104
1430 2.25 7.61 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 0.0185 278
3.00 0.0240 360
4.00 0.0319 480
5.00 0.0399 601
6.00 0.0479 721
7.00 0.0559 841
8.00 0.0639 961
9.00 0.0719 1080
10.0 0.0799 1200
20.0 0.160 2400
30.0 0.240 3600
40.0 0.319 4800
50.0 0.399 6010
60.0 0.479 7210
70.0 0.559 8410
80.0 0.639 9610
90.0 0.719 1.08 × 104
100 0.799 1.20 × 104
200 1.60 2.40 × 104
300 2.40 3.60 × 104
400 3.19 4.80 × 104
500 3.99 6.01 × 104
501 4.00 6.02 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 0.0583 493
3.00 0.0757 641
4.00 0.101 854
5.00 0.126 1070
6.00 0.151 1280
7.00 0.177 1490
8.00 0.202 1710
9.00 0.227 1920
10.0 0.252 2140
20.0 0.505 4270
30.0 0.757 6410
40.0 1.01 8540
50.0 1.26 1.07 × 104
60.0 1.51 1.28 × 104
70.0 1.77 1.49 × 104
80.0 2.02 1.71 × 104
90.0 2.27 1.92 × 104
100 2.52 2.14 × 104
158 4.00 3.38 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 0.142 771
3.00 0.185 1000
4.00 0.246 1330
5.00 0.308 1670
6.00 0.370 2000
7.00 0.431 2340
8.00 0.493 2670
9.00 0.555 3000
10.0 0.616 3340
20.0 1.23 6670
30.0 1.85 1.00 × 104
40.0 2.46 1.33 × 104
50.0 3.08 1.67 × 104
60.0 3.70 2.00 × 104
64.9 4.00 2.17 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 0.295 1110
3.00 0.383 1440
4.00 0.511 1920
5.00 0.639 2400
6.00 0.767 2880
7.00 0.894 3360
8.00 1.02 3840
9.00 1.15 4320
10.0 1.28 4800
20.0 2.56 9610
30.0 3.83 1.44 × 104
31.3 4.00 1.50 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 0.933 1970
3.00 1.21 2560
4.00 1.62 3420
5.00 2.02 4270
6.00 2.42 5120
7.00 2.83 5980
8.00 3.23 6830
9.00 3.63 7690
9.91 4.00 8460
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.31 2.28 3080
3.00 2.96 4000
4.00 3.94 5340
4.06 4.00 5410
Additional Information
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Injection Molding Design Guide

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

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

CNC Machining Design Guide

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

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

more publications