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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Two 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 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 = 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_mid (in) stress_max (psi)
6.18 7.44 × 10-6 5.59
7.00 8.42 × 10-6 6.33
8.00 9.62 × 10-6 7.24
9.00 1.08 × 10-5 8.14
10.0 1.20 × 10-5 9.05
20.0 2.41 × 10-5 18.1
30.0 3.61 × 10-5 27.1
40.0 4.81 × 10-5 36.2
50.0 6.01 × 10-5 45.2
60.0 7.22 × 10-5 54.3
70.0 8.42 × 10-5 63.3
80.0 9.62 × 10-5 72.4
90.0 1.08 × 10-4 81.4
100 1.20 × 10-4 90.5
200 2.41 × 10-4 181
300 3.61 × 10-4 271
400 4.81 × 10-4 362
500 6.01 × 10-4 452
600 7.22 × 10-4 543
700 8.42 × 10-4 633
800 9.62 × 10-4 724
900 0.00108 814
1000 0.00120 905
2000 0.00241 1810
3000 0.00361 2710
4000 0.00481 3620
5000 0.00601 4520
6000 0.00722 5430
7000 0.00842 6330
8000 0.00962 7240
9000 0.0108 8140
1.00 × 104 0.0120 9050
2.00 × 104 0.0241 1.81 × 104
3.00 × 104 0.0361 2.71 × 104
4.00 × 104 0.0481 3.62 × 104
5.00 × 104 0.0601 4.52 × 104
6.00 × 104 0.0722 5.43 × 104
7.00 × 104 0.0842 6.33 × 104
8.00 × 104 0.0962 7.24 × 104
8.42 × 104 0.101 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_mid (in) stress_max (psi)
6.18 5.74 × 10-5 15.5
7.00 6.50 × 10-5 17.6
8.00 7.43 × 10-5 20.1
9.00 8.35 × 10-5 22.6
10.0 9.28 × 10-5 25.1
20.0 1.86 × 10-4 50.3
30.0 2.78 × 10-4 75.4
40.0 3.71 × 10-4 101
50.0 4.64 × 10-4 126
60.0 5.57 × 10-4 151
70.0 6.50 × 10-4 176
80.0 7.43 × 10-4 201
90.0 8.35 × 10-4 226
100 9.28 × 10-4 251
200 0.00186 503
300 0.00278 754
400 0.00371 1010
500 0.00464 1260
600 0.00557 1510
700 0.00650 1760
800 0.00743 2010
900 0.00835 2260
1000 0.00928 2510
2000 0.0186 5030
3000 0.0278 7540
4000 0.0371 1.01 × 104
5000 0.0464 1.26 × 104
6000 0.0557 1.51 × 104
7000 0.0650 1.76 × 104
8000 0.0743 2.01 × 104
9000 0.0835 2.26 × 104
1.00 × 104 0.0928 2.51 × 104
2.00 × 104 0.186 5.03 × 104
3.00 × 104 0.278 7.54 × 104
3.03 × 104 0.281 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_mid (in) stress_max (psi)
6.18 9.18 × 10-4 62.1
7.00 0.00104 70.4
8.00 0.00119 80.4
9.00 0.00134 90.5
10.0 0.00149 101
20.0 0.00297 201
30.0 0.00446 302
40.0 0.00594 402
50.0 0.00743 503
60.0 0.00891 603
70.0 0.0104 704
80.0 0.0119 804
90.0 0.0134 905
100 0.0149 1010
200 0.0297 2010
300 0.0446 3020
400 0.0594 4020
500 0.0743 5030
600 0.0891 6030
700 0.104 7040
800 0.119 8040
900 0.134 9050
1000 0.149 1.01 × 104
2000 0.297 2.01 × 104
3000 0.446 3.02 × 104
4000 0.594 4.02 × 104
5000 0.743 5.03 × 104
6000 0.891 6.03 × 104
7000 1.04 7.04 × 104
7580 1.13 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_mid (in) stress_max (psi)
6.18 0.00465 140
7.00 0.00526 158
8.00 0.00601 181
9.00 0.00677 204
10.0 0.00752 226
20.0 0.0150 452
30.0 0.0226 679
40.0 0.0301 905
50.0 0.0376 1130
60.0 0.0451 1360
70.0 0.0526 1580
80.0 0.0601 1810
90.0 0.0677 2040
100 0.0752 2260
200 0.150 4520
300 0.226 6790
400 0.301 9050
500 0.376 1.13 × 104
600 0.451 1.36 × 104
700 0.526 1.58 × 104
800 0.601 1.81 × 104
900 0.677 2.04 × 104
1000 0.752 2.26 × 104
2000 1.50 4.52 × 104
3000 2.26 6.79 × 104
3370 2.53 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_mid (in) stress_max (psi)
6.18 0.0147 249
7.00 0.0166 281
8.00 0.0190 322
9.00 0.0214 362
10.0 0.0238 402
20.0 0.0475 804
30.0 0.0713 1210
40.0 0.0950 1610
50.0 0.119 2010
60.0 0.143 2410
70.0 0.166 2810
80.0 0.190 3220
90.0 0.214 3620
100 0.238 4020
200 0.475 8040
300 0.713 1.21 × 104
400 0.950 1.61 × 104
500 1.19 2.01 × 104
600 1.43 2.41 × 104
700 1.66 2.81 × 104
800 1.90 3.22 × 104
900 2.14 3.62 × 104
1000 2.38 4.02 × 104
1890 4.50 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_mid (in) stress_max (psi)
6.18 0.0359 388
7.00 0.0406 440
8.00 0.0464 503
9.00 0.0522 565
10.0 0.0580 628
20.0 0.116 1260
30.0 0.174 1880
40.0 0.232 2510
50.0 0.290 3140
60.0 0.348 3770
70.0 0.406 4400
80.0 0.464 5030
90.0 0.522 5650
100 0.580 6280
200 1.16 1.26 × 104
300 1.74 1.88 × 104
400 2.32 2.51 × 104
500 2.90 3.14 × 104
600 3.48 3.77 × 104
700 4.06 4.40 × 104
800 4.64 5.03 × 104
900 5.22 5.65 × 104
1000 5.80 6.28 × 104
1210 7.03 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_mid (in) stress_max (psi)
6.18 0.0744 559
7.00 0.0842 633
8.00 0.0962 724
9.00 0.108 814
10.0 0.120 905
20.0 0.241 1810
30.0 0.361 2710
40.0 0.481 3620
50.0 0.601 4520
60.0 0.722 5430
70.0 0.842 6330
80.0 0.962 7240
90.0 1.08 8140
100 1.20 9050
200 2.41 1.81 × 104
300 3.61 2.71 × 104
400 4.81 3.62 × 104
500 6.01 4.52 × 104
600 7.22 5.43 × 104
665 8.00 6.02 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
6.18 0.235 994
7.00 0.266 1130
8.00 0.304 1290
9.00 0.342 1450
10.0 0.380 1610
20.0 0.760 3220
30.0 1.14 4820
40.0 1.52 6430
50.0 1.90 8040
60.0 2.28 9650
70.0 2.66 1.13 × 104
80.0 3.04 1.29 × 104
90.0 3.42 1.45 × 104
100 3.80 1.61 × 104
200 7.60 3.22 × 104
210 8.00 3.38 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
6.18 0.574 1550
7.00 0.650 1760
8.00 0.743 2010
9.00 0.835 2260
10.0 0.928 2510
20.0 1.86 5030
30.0 2.78 7540
40.0 3.71 1.01 × 104
50.0 4.64 1.26 × 104
60.0 5.57 1.51 × 104
70.0 6.50 1.76 × 104
80.0 7.43 2.01 × 104
86.2 8.00 2.17 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 60.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
6.18 1.19 2240
7.00 1.35 2530
8.00 1.54 2890
9.00 1.73 3260
10.0 1.92 3620
20.0 3.85 7240
30.0 5.77 1.09 × 104
40.0 7.70 1.45 × 104
41.6 8.00 1.50 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 70.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
6.18 2.20 3040
7.00 2.50 3450
8.00 2.85 3940
9.00 3.21 4430
10.0 3.57 4930
20.0 7.13 9850
22.4 8.00 1.11 × 104
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 80.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
6.18 3.76 3980
7.00 4.26 4500
8.00 4.87 5150
9.00 5.47 5790
10.0 6.08 6430
13.2 8.00 8460
Aluminum I Beam: 8.00 × 6.181 (8.00 inch tall × 6.181 lbf/ft)
L = 90.0 ft
P (lbf/ft) w_mid (in) stress_max (psi)
6.18 6.02 5030
7.00 6.82 5700
8.00 7.80 6510
8.21 8.00 6680
Additional Information
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