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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Four 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 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 = 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_max (in) stress_max (psi)
2.79 3.62 × 10-5 9.63
3.00 3.88 × 10-5 10.3
4.00 5.18 × 10-5 13.8
5.00 6.47 × 10-5 17.2
6.00 7.77 × 10-5 20.7
7.00 9.06 × 10-5 24.1
8.00 1.04 × 10-4 27.6
9.00 1.16 × 10-4 31.0
10.0 1.29 × 10-4 34.5
20.0 2.59 × 10-4 69.0
30.0 3.88 × 10-4 103
40.0 5.18 × 10-4 138
50.0 6.47 × 10-4 172
60.0 7.77 × 10-4 207
70.0 9.06 × 10-4 241
80.0 0.00104 276
90.0 0.00116 310
100 0.00129 345
200 0.00259 690
300 0.00388 1030
400 0.00518 1380
500 0.00647 1720
600 0.00777 2070
700 0.00906 2410
800 0.0104 2760
900 0.0116 3100
1000 0.0129 3450
2000 0.0259 6900
3000 0.0388 1.03 × 104
4000 0.0518 1.38 × 104
5000 0.0647 1.72 × 104
6000 0.0777 2.07 × 104
7000 0.0906 2.41 × 104
8000 0.104 2.76 × 104
9000 0.116 3.10 × 104
1.00 × 104 0.129 3.45 × 104
2.00 × 104 0.259 6.90 × 104
2.21 × 104 0.286 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_max (in) stress_max (psi)
2.79 2.79 × 10-4 26.7
3.00 3.00 × 10-4 28.7
4.00 4.00 × 10-4 38.3
5.00 4.99 × 10-4 47.9
6.00 5.99 × 10-4 57.5
7.00 6.99 × 10-4 67.0
8.00 7.99 × 10-4 76.6
9.00 8.99 × 10-4 86.2
10.0 9.99 × 10-4 95.8
20.0 0.00200 192
30.0 0.00300 287
40.0 0.00400 383
50.0 0.00499 479
60.0 0.00599 575
70.0 0.00699 670
80.0 0.00799 766
90.0 0.00899 862
100 0.00999 958
200 0.0200 1920
300 0.0300 2870
400 0.0400 3830
500 0.0499 4790
600 0.0599 5750
700 0.0699 6700
800 0.0799 7660
900 0.0899 8620
1000 0.0999 9580
2000 0.200 1.92 × 104
3000 0.300 2.87 × 104
4000 0.400 3.83 × 104
5000 0.499 4.79 × 104
6000 0.599 5.75 × 104
7000 0.699 6.70 × 104
7950 0.794 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_max (in) stress_max (psi)
2.79 0.00446 107
3.00 0.00479 115
4.00 0.00639 153
5.00 0.00799 192
6.00 0.00959 230
7.00 0.0112 268
8.00 0.0128 306
9.00 0.0144 345
10.0 0.0160 383
20.0 0.0320 766
30.0 0.0479 1150
40.0 0.0639 1530
50.0 0.0799 1920
60.0 0.0959 2300
70.0 0.112 2680
80.0 0.128 3060
90.0 0.144 3450
100 0.160 3830
200 0.320 7660
300 0.479 1.15 × 104
400 0.639 1.53 × 104
500 0.799 1.92 × 104
600 0.959 2.30 × 104
700 1.12 2.68 × 104
800 1.28 3.06 × 104
900 1.44 3.45 × 104
1000 1.60 3.83 × 104
1990 3.18 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_max (in) stress_max (psi)
2.79 0.0226 241
3.00 0.0243 259
4.00 0.0324 345
5.00 0.0404 431
6.00 0.0485 517
7.00 0.0566 603
8.00 0.0647 690
9.00 0.0728 776
10.0 0.0809 862
20.0 0.162 1720
30.0 0.243 2590
40.0 0.324 3450
50.0 0.404 4310
60.0 0.485 5170
70.0 0.566 6030
80.0 0.647 6900
90.0 0.728 7760
100 0.809 8620
200 1.62 1.72 × 104
300 2.43 2.59 × 104
400 3.24 3.45 × 104
494 4.00 4.26 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.79 0.0714 428
3.00 0.0767 460
4.00 0.102 613
5.00 0.128 766
6.00 0.153 919
7.00 0.179 1070
8.00 0.205 1230
9.00 0.230 1380
10.0 0.256 1530
20.0 0.511 3060
30.0 0.767 4600
40.0 1.02 6130
50.0 1.28 7660
60.0 1.53 9190
70.0 1.79 1.07 × 104
80.0 2.05 1.23 × 104
90.0 2.30 1.38 × 104
100 2.56 1.53 × 104
156 4.00 2.40 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.79 0.174 669
3.00 0.187 718
4.00 0.250 958
5.00 0.312 1200
6.00 0.375 1440
7.00 0.437 1680
8.00 0.499 1920
9.00 0.562 2150
10.0 0.624 2390
20.0 1.25 4790
30.0 1.87 7180
40.0 2.50 9580
50.0 3.12 1.20 × 104
60.0 3.75 1.44 × 104
64.1 4.00 1.53 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.79 0.362 963
3.00 0.388 1030
4.00 0.518 1380
5.00 0.647 1720
6.00 0.777 2070
7.00 0.906 2410
8.00 1.04 2760
9.00 1.16 3100
10.0 1.29 3450
20.0 2.59 6900
30.0 3.88 1.03 × 104
30.9 4.00 1.07 × 104
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.79 1.14 1710
3.00 1.23 1840
4.00 1.64 2450
5.00 2.05 3060
6.00 2.45 3680
7.00 2.86 4290
8.00 3.27 4900
9.00 3.68 5520
9.78 4.00 5990
Aluminum I Beam: 4.00 × 2.793 (4.00 inch tall × 2.793 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.79 2.79 2670
3.00 3.00 2870
4.00 4.00 3830
4.00 4.00 3840
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