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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Three Equal Spans » Aluminum I Beam » 8.00 × 6.181
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 = 59.69 in4) for the 8.00 × 6.181 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
L = 70 ft
L = 80 ft
L = 90 ft
   
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 9.71 × 10-6 4.47
7.00 1.10 × 10-5 5.07
8.00 1.26 × 10-5 5.79
9.00 1.41 × 10-5 6.51
10.0 1.57 × 10-5 7.24
20.0 3.14 × 10-5 14.5
30.0 4.71 × 10-5 21.7
40.0 6.28 × 10-5 28.9
50.0 7.85 × 10-5 36.2
60.0 9.42 × 10-5 43.4
70.0 1.10 × 10-4 50.7
80.0 1.26 × 10-4 57.9
90.0 1.41 × 10-4 65.1
100 1.57 × 10-4 72.4
200 3.14 × 10-4 145
300 4.71 × 10-4 217
400 6.28 × 10-4 289
500 7.85 × 10-4 362
600 9.42 × 10-4 434
700 0.00110 507
800 0.00126 579
900 0.00141 651
1000 0.00157 724
2000 0.00314 1450
3000 0.00471 2170
4000 0.00628 2890
5000 0.00785 3620
6000 0.00942 4340
7000 0.0110 5070
8000 0.0126 5790
9000 0.0141 6510
1.00 × 104 0.0157 7240
2.00 × 104 0.0314 1.45 × 104
3.00 × 104 0.0471 2.17 × 104
4.00 × 104 0.0628 2.89 × 104
5.00 × 104 0.0785 3.62 × 104
6.00 × 104 0.0942 4.34 × 104
7.00 × 104 0.110 5.07 × 104
8.00 × 104 0.126 5.79 × 104
9.00 × 104 0.141 6.51 × 104
1.00 × 105 0.157 7.24 × 104
1.05 × 105 0.165 7.61 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 7.49 × 10-5 12.4
7.00 8.48 × 10-5 14.1
8.00 9.69 × 10-5 16.1
9.00 1.09 × 10-4 18.1
10.0 1.21 × 10-4 20.1
20.0 2.42 × 10-4 40.2
30.0 3.64 × 10-4 60.3
40.0 4.85 × 10-4 80.4
50.0 6.06 × 10-4 101
60.0 7.27 × 10-4 121
70.0 8.48 × 10-4 141
80.0 9.69 × 10-4 161
90.0 0.00109 181
100 0.00121 201
200 0.00242 402
300 0.00364 603
400 0.00485 804
500 0.00606 1010
600 0.00727 1210
700 0.00848 1410
800 0.00969 1610
900 0.0109 1810
1000 0.0121 2010
2000 0.0242 4020
3000 0.0364 6030
4000 0.0485 8040
5000 0.0606 1.01 × 104
6000 0.0727 1.21 × 104
7000 0.0848 1.41 × 104
8000 0.0969 1.61 × 104
9000 0.109 1.81 × 104
1.00 × 104 0.121 2.01 × 104
2.00 × 104 0.242 4.02 × 104
3.00 × 104 0.364 6.03 × 104
3.79 × 104 0.459 7.61 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.00120 49.7
7.00 0.00136 56.3
8.00 0.00155 64.3
9.00 0.00175 72.4
10.0 0.00194 80.4
20.0 0.00388 161
30.0 0.00582 241
40.0 0.00776 322
50.0 0.00969 402
60.0 0.0116 482
70.0 0.0136 563
80.0 0.0155 643
90.0 0.0175 724
100 0.0194 804
200 0.0388 1610
300 0.0582 2410
400 0.0776 3220
500 0.0969 4020
600 0.116 4820
700 0.136 5630
800 0.155 6430
900 0.175 7240
1000 0.194 8040
2000 0.388 1.61 × 104
3000 0.582 2.41 × 104
4000 0.776 3.22 × 104
5000 0.969 4.02 × 104
6000 1.16 4.82 × 104
7000 1.36 5.63 × 104
8000 1.55 6.43 × 104
9000 1.75 7.24 × 104
9470 1.84 7.61 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.00607 112
7.00 0.00687 127
8.00 0.00785 145
9.00 0.00883 163
10.0 0.00982 181
20.0 0.0196 362
30.0 0.0294 543
40.0 0.0393 724
50.0 0.0491 905
60.0 0.0589 1090
70.0 0.0687 1270
80.0 0.0785 1450
90.0 0.0883 1630
100 0.0982 1810
200 0.196 3620
300 0.294 5430
400 0.393 7240
500 0.491 9050
600 0.589 1.09 × 104
700 0.687 1.27 × 104
800 0.785 1.45 × 104
900 0.883 1.63 × 104
1000 0.982 1.81 × 104
2000 1.96 3.62 × 104
3000 2.94 5.43 × 104
4000 3.93 7.24 × 104
4210 4.13 7.61 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.0192 199
7.00 0.0217 225
8.00 0.0248 257
9.00 0.0279 289
10.0 0.0310 322
20.0 0.0620 643
30.0 0.0931 965
40.0 0.124 1290
50.0 0.155 1610
60.0 0.186 1930
70.0 0.217 2250
80.0 0.248 2570
90.0 0.279 2890
100 0.310 3220
200 0.620 6430
300 0.931 9650
400 1.24 1.29 × 104
500 1.55 1.61 × 104
600 1.86 1.93 × 104
700 2.17 2.25 × 104
800 2.48 2.57 × 104
900 2.79 2.89 × 104
1000 3.10 3.22 × 104
2000 6.20 6.43 × 104
2370 7.34 7.61 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.0468 311
7.00 0.0530 352
8.00 0.0606 402
9.00 0.0682 452
10.0 0.0757 503
20.0 0.151 1010
30.0 0.227 1510
40.0 0.303 2010
50.0 0.379 2510
60.0 0.454 3020
70.0 0.530 3520
80.0 0.606 4020
90.0 0.682 4520
100 0.757 5030
200 1.51 1.01 × 104
300 2.27 1.51 × 104
400 3.03 2.01 × 104
500 3.79 2.51 × 104
600 4.54 3.02 × 104
700 5.30 3.52 × 104
800 6.06 4.02 × 104
900 6.82 4.52 × 104
1000 7.57 5.03 × 104
1520 11.5 7.61 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.0971 447
7.00 0.110 507
8.00 0.126 579
9.00 0.141 651
10.0 0.157 724
20.0 0.314 1450
30.0 0.471 2170
40.0 0.628 2890
50.0 0.785 3620
60.0 0.942 4340
70.0 1.10 5070
80.0 1.26 5790
90.0 1.41 6510
100 1.57 7240
200 3.14 1.45 × 104
300 4.71 2.17 × 104
400 6.28 2.89 × 104
500 7.85 3.62 × 104
509 8.00 3.69 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.307 795
7.00 0.347 901
8.00 0.397 1030
9.00 0.447 1160
10.0 0.496 1290
20.0 0.993 2570
30.0 1.49 3860
40.0 1.99 5150
50.0 2.48 6430
60.0 2.98 7720
70.0 3.47 9010
80.0 3.97 1.03 × 104
90.0 4.47 1.16 × 104
100 4.96 1.29 × 104
161 8.00 2.07 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 0.749 1240
7.00 0.848 1410
8.00 0.969 1610
9.00 1.09 1810
10.0 1.21 2010
20.0 2.42 4020
30.0 3.64 6030
40.0 4.85 8040
50.0 6.06 1.01 × 104
60.0 7.27 1.21 × 104
66.0 8.00 1.33 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 60.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 1.55 1790
7.00 1.76 2030
8.00 2.01 2320
9.00 2.26 2610
10.0 2.51 2890
20.0 5.03 5790
30.0 7.54 8680
31.8 8.00 9220
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 70.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 2.88 2440
7.00 3.26 2760
8.00 3.72 3150
9.00 4.19 3550
10.0 4.66 3940
17.2 8.00 6770
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 80.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 4.91 3180
7.00 5.56 3600
8.00 6.35 4120
9.00 7.15 4630
10.0 7.94 5150
10.1 8.00 5180
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 90.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
6.18 7.86 4030
6.29 8.00 4100
Additional Information
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Mechanical Engineers Outlook

Guide for those interested in becoming a mechanical engineer. Includes qualifications, pay, and job duties.

Metal 3D Printing Design Guide

Direct Metal Laser Sintering (DMLS) 3D printing for parts with reduced cost and little waste.

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more publications