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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Three Equal Spans » Aluminum I Beam » 5.00 × 3.700
Aluminum I Beam | Single Span | Two Equal Spans | Three Equal Spans | Four Equal Spans

For a simply supported beam in three equal spans, we compute the displacement at the middle of the first and the third spans, and the maximum normal stress stress_max occuring at the second and third supports of the beam.
The tabulated data listed in this page are calculated based on the area moment of inertia (Ixx = 13.94 in4) for the 5.00 × 3.700 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
L = 60 ft
   
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 2.49 × 10-5 7.17
4.00 2.69 × 10-5 7.75
5.00 3.36 × 10-5 9.68
6.00 4.04 × 10-5 11.6
7.00 4.71 × 10-5 13.6
8.00 5.38 × 10-5 15.5
9.00 6.05 × 10-5 17.4
10.0 6.73 × 10-5 19.4
20.0 1.35 × 10-4 38.7
30.0 2.02 × 10-4 58.1
40.0 2.69 × 10-4 77.5
50.0 3.36 × 10-4 96.8
60.0 4.04 × 10-4 116
70.0 4.71 × 10-4 136
80.0 5.38 × 10-4 155
90.0 6.05 × 10-4 174
100 6.73 × 10-4 194
200 0.00135 387
300 0.00202 581
400 0.00269 775
500 0.00336 968
600 0.00404 1160
700 0.00471 1360
800 0.00538 1550
900 0.00605 1740
1000 0.00673 1940
2000 0.0135 3870
3000 0.0202 5810
4000 0.0269 7750
5000 0.0336 9680
6000 0.0404 1.16 × 104
7000 0.0471 1.36 × 104
8000 0.0538 1.55 × 104
9000 0.0605 1.74 × 104
1.00 × 104 0.0673 1.94 × 104
2.00 × 104 0.135 3.87 × 104
3.00 × 104 0.202 5.81 × 104
3.93 × 104 0.264 7.61 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 1.92 × 10-4 19.9
4.00 2.08 × 10-4 21.5
5.00 2.59 × 10-4 26.9
6.00 3.11 × 10-4 32.3
7.00 3.63 × 10-4 37.7
8.00 4.15 × 10-4 43.0
9.00 4.67 × 10-4 48.4
10.0 5.19 × 10-4 53.8
20.0 0.00104 108
30.0 0.00156 161
40.0 0.00208 215
50.0 0.00259 269
60.0 0.00311 323
70.0 0.00363 377
80.0 0.00415 430
90.0 0.00467 484
100 0.00519 538
200 0.0104 1080
300 0.0156 1610
400 0.0208 2150
500 0.0259 2690
600 0.0311 3230
700 0.0363 3770
800 0.0415 4300
900 0.0467 4840
1000 0.0519 5380
2000 0.104 1.08 × 104
3000 0.156 1.61 × 104
4000 0.208 2.15 × 104
5000 0.259 2.69 × 104
6000 0.311 3.23 × 104
7000 0.363 3.77 × 104
8000 0.415 4.30 × 104
9000 0.467 4.84 × 104
1.00 × 104 0.519 5.38 × 104
1.42 × 104 0.734 7.61 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 0.00307 79.6
4.00 0.00332 86.1
5.00 0.00415 108
6.00 0.00498 129
7.00 0.00581 151
8.00 0.00664 172
9.00 0.00747 194
10.0 0.00830 215
20.0 0.0166 430
30.0 0.0249 646
40.0 0.0332 861
50.0 0.0415 1080
60.0 0.0498 1290
70.0 0.0581 1510
80.0 0.0664 1720
90.0 0.0747 1940
100 0.0830 2150
200 0.166 4300
300 0.249 6460
400 0.332 8610
500 0.415 1.08 × 104
600 0.498 1.29 × 104
700 0.581 1.51 × 104
800 0.664 1.72 × 104
900 0.747 1.94 × 104
1000 0.830 2.15 × 104
2000 1.66 4.30 × 104
3000 2.49 6.46 × 104
3540 2.94 7.61 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 0.0156 179
4.00 0.0168 194
5.00 0.0210 242
6.00 0.0252 291
7.00 0.0294 339
8.00 0.0336 387
9.00 0.0378 436
10.0 0.0420 484
20.0 0.0841 968
30.0 0.126 1450
40.0 0.168 1940
50.0 0.210 2420
60.0 0.252 2910
70.0 0.294 3390
80.0 0.336 3870
90.0 0.378 4360
100 0.420 4840
200 0.841 9680
300 1.26 1.45 × 104
400 1.68 1.94 × 104
500 2.10 2.42 × 104
600 2.52 2.91 × 104
700 2.94 3.39 × 104
800 3.36 3.87 × 104
900 3.78 4.36 × 104
1000 4.20 4.84 × 104
1570 6.61 7.61 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 0.0492 319
4.00 0.0531 344
5.00 0.0664 430
6.00 0.0797 516
7.00 0.0930 603
8.00 0.106 689
9.00 0.120 775
10.0 0.133 861
20.0 0.266 1720
30.0 0.399 2580
40.0 0.531 3440
50.0 0.664 4300
60.0 0.797 5160
70.0 0.930 6030
80.0 1.06 6890
90.0 1.20 7750
100 1.33 8610
200 2.66 1.72 × 104
300 3.99 2.58 × 104
376 5.00 3.24 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 0.120 498
4.00 0.130 538
5.00 0.162 673
6.00 0.195 807
7.00 0.227 942
8.00 0.259 1080
9.00 0.292 1210
10.0 0.324 1350
20.0 0.649 2690
30.0 0.973 4040
40.0 1.30 5380
50.0 1.62 6730
60.0 1.95 8070
70.0 2.27 9420
80.0 2.59 1.08 × 104
90.0 2.92 1.21 × 104
100 3.24 1.35 × 104
154 5.00 2.07 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 0.249 717
4.00 0.269 775
5.00 0.336 968
6.00 0.404 1160
7.00 0.471 1360
8.00 0.538 1550
9.00 0.605 1740
10.0 0.673 1940
20.0 1.35 3870
30.0 2.02 5810
40.0 2.69 7750
50.0 3.36 9680
60.0 4.04 1.16 × 104
70.0 4.71 1.36 × 104
74.3 5.00 1.44 × 104
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 0.786 1270
4.00 0.850 1380
5.00 1.06 1720
6.00 1.28 2070
7.00 1.49 2410
8.00 1.70 2750
9.00 1.91 3100
10.0 2.13 3440
20.0 4.25 6890
23.5 5.00 8100
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 1.92 1990
4.00 2.08 2150
5.00 2.59 2690
6.00 3.11 3230
7.00 3.63 3770
8.00 4.15 4300
9.00 4.67 4840
9.64 5.00 5180
Aluminum I Beam: 5.00 × 3.700 (5.00 inch tall × 3.700 lbf/ft)
L = 60.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
3.70 3.98 2870
4.00 4.30 3100
4.65 5.00 3600
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