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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Two Equal Spans » Aluminum I Beam » 4.00 × 2.793
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 = 6.71 in4) for the 4.00 × 2.793 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 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 2.99 × 10-5 11.2
3.00 3.21 × 10-5 12.1
4.00 4.28 × 10-5 16.1
5.00 5.35 × 10-5 20.1
6.00 6.42 × 10-5 24.1
7.00 7.49 × 10-5 28.2
8.00 8.56 × 10-5 32.2
9.00 9.63 × 10-5 36.2
10.0 1.07 × 10-4 40.2
20.0 2.14 × 10-4 80.5
30.0 3.21 × 10-4 121
40.0 4.28 × 10-4 161
50.0 5.35 × 10-4 201
60.0 6.42 × 10-4 241
70.0 7.49 × 10-4 282
80.0 8.56 × 10-4 322
90.0 9.63 × 10-4 362
100 0.00107 402
200 0.00214 805
300 0.00321 1210
400 0.00428 1610
500 0.00535 2010
600 0.00642 2410
700 0.00749 2820
800 0.00856 3220
900 0.00963 3620
1000 0.0107 4020
2000 0.0214 8050
3000 0.0321 1.21 × 104
4000 0.0428 1.61 × 104
5000 0.0535 2.01 × 104
6000 0.0642 2.41 × 104
7000 0.0749 2.82 × 104
8000 0.0856 3.22 × 104
9000 0.0963 3.62 × 104
1.00 × 104 0.107 4.02 × 104
1.89 × 104 0.202 7.61 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 2.31 × 10-4 31.2
3.00 2.48 × 10-4 33.5
4.00 3.30 × 10-4 44.7
5.00 4.13 × 10-4 55.9
6.00 4.95 × 10-4 67.1
7.00 5.78 × 10-4 78.2
8.00 6.61 × 10-4 89.4
9.00 7.43 × 10-4 101
10.0 8.26 × 10-4 112
20.0 0.00165 224
30.0 0.00248 335
40.0 0.00330 447
50.0 0.00413 559
60.0 0.00495 671
70.0 0.00578 782
80.0 0.00661 894
90.0 0.00743 1010
100 0.00826 1120
200 0.0165 2240
300 0.0248 3350
400 0.0330 4470
500 0.0413 5590
600 0.0495 6710
700 0.0578 7820
800 0.0661 8940
900 0.0743 1.01 × 104
1000 0.0826 1.12 × 104
2000 0.165 2.24 × 104
3000 0.248 3.35 × 104
4000 0.330 4.47 × 104
5000 0.413 5.59 × 104
6000 0.495 6.71 × 104
6810 0.562 7.61 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 0.00369 125
3.00 0.00396 134
4.00 0.00528 179
5.00 0.00661 224
6.00 0.00793 268
7.00 0.00925 313
8.00 0.0106 358
9.00 0.0119 402
10.0 0.0132 447
20.0 0.0264 894
30.0 0.0396 1340
40.0 0.0528 1790
50.0 0.0661 2240
60.0 0.0793 2680
70.0 0.0925 3130
80.0 0.106 3580
90.0 0.119 4020
100 0.132 4470
200 0.264 8940
300 0.396 1.34 × 104
400 0.528 1.79 × 104
500 0.661 2.24 × 104
600 0.793 2.68 × 104
700 0.925 3.13 × 104
800 1.06 3.58 × 104
900 1.19 4.02 × 104
1000 1.32 4.47 × 104
1700 2.25 7.61 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 0.0187 281
3.00 0.0201 302
4.00 0.0268 402
5.00 0.0334 503
6.00 0.0401 604
7.00 0.0468 704
8.00 0.0535 805
9.00 0.0602 905
10.0 0.0669 1010
20.0 0.134 2010
30.0 0.201 3020
40.0 0.268 4020
50.0 0.334 5030
60.0 0.401 6040
70.0 0.468 7040
80.0 0.535 8050
90.0 0.602 9050
100 0.669 1.01 × 104
200 1.34 2.01 × 104
300 2.01 3.02 × 104
400 2.68 4.02 × 104
500 3.34 5.03 × 104
598 4.00 6.02 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 0.0590 499
3.00 0.0634 537
4.00 0.0846 715
5.00 0.106 894
6.00 0.127 1070
7.00 0.148 1250
8.00 0.169 1430
9.00 0.190 1610
10.0 0.211 1790
20.0 0.423 3580
30.0 0.634 5370
40.0 0.846 7150
50.0 1.06 8940
60.0 1.27 1.07 × 104
70.0 1.48 1.25 × 104
80.0 1.69 1.43 × 104
90.0 1.90 1.61 × 104
100 2.11 1.79 × 104
189 4.00 3.38 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 0.144 780
3.00 0.155 838
4.00 0.206 1120
5.00 0.258 1400
6.00 0.310 1680
7.00 0.361 1960
8.00 0.413 2240
9.00 0.464 2510
10.0 0.516 2790
20.0 1.03 5590
30.0 1.55 8380
40.0 2.06 1.12 × 104
50.0 2.58 1.40 × 104
60.0 3.10 1.68 × 104
70.0 3.61 1.96 × 104
77.5 4.00 2.17 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 0.299 1120
3.00 0.321 1210
4.00 0.428 1610
5.00 0.535 2010
6.00 0.642 2410
7.00 0.749 2820
8.00 0.856 3220
9.00 0.963 3620
10.0 1.07 4020
20.0 2.14 8050
30.0 3.21 1.21 × 104
37.4 4.00 1.50 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 0.945 2000
3.00 1.01 2150
4.00 1.35 2860
5.00 1.69 3580
6.00 2.03 4290
7.00 2.37 5010
8.00 2.71 5720
9.00 3.04 6440
10.0 3.38 7150
11.8 4.00 8460
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
2.79 2.31 3120
3.00 2.48 3350
4.00 3.30 4470
4.84 4.00 5410
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A white paper to assist in the evaluation of 3D scanning hardware solutions.

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