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Glossary » Beams » Simply Supported » Uniformly Distributed Load » Four Equal Spans » Aluminum I Beam » 4.00 × 2.311
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 = 5.62 in4) for the 4.00 × 2.311 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 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 3.57 × 10-5 9.51
3.00 4.64 × 10-5 12.3
4.00 6.18 × 10-5 16.5
5.00 7.73 × 10-5 20.6
6.00 9.27 × 10-5 24.7
7.00 1.08 × 10-4 28.8
8.00 1.24 × 10-4 32.9
9.00 1.39 × 10-4 37.0
10.0 1.55 × 10-4 41.2
20.0 3.09 × 10-4 82.3
30.0 4.64 × 10-4 123
40.0 6.18 × 10-4 165
50.0 7.73 × 10-4 206
60.0 9.27 × 10-4 247
70.0 0.00108 288
80.0 0.00124 329
90.0 0.00139 370
100 0.00155 412
200 0.00309 823
300 0.00464 1230
400 0.00618 1650
500 0.00773 2060
600 0.00927 2470
700 0.0108 2880
800 0.0124 3290
900 0.0139 3700
1000 0.0155 4120
2000 0.0309 8230
3000 0.0464 1.23 × 104
4000 0.0618 1.65 × 104
5000 0.0773 2.06 × 104
6000 0.0927 2.47 × 104
7000 0.108 2.88 × 104
8000 0.124 3.29 × 104
9000 0.139 3.70 × 104
1.00 × 104 0.155 4.12 × 104
1.85 × 104 0.286 7.61 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 2.76 × 10-4 26.4
3.00 3.58 × 10-4 34.3
4.00 4.77 × 10-4 45.7
5.00 5.96 × 10-4 57.2
6.00 7.15 × 10-4 68.6
7.00 8.35 × 10-4 80.0
8.00 9.54 × 10-4 91.5
9.00 0.00107 103
10.0 0.00119 114
20.0 0.00238 229
30.0 0.00358 343
40.0 0.00477 457
50.0 0.00596 572
60.0 0.00715 686
70.0 0.00835 800
80.0 0.00954 915
90.0 0.0107 1030
100 0.0119 1140
200 0.0238 2290
300 0.0358 3430
400 0.0477 4570
500 0.0596 5720
600 0.0715 6860
700 0.0835 8000
800 0.0954 9150
900 0.107 1.03 × 104
1000 0.119 1.14 × 104
2000 0.238 2.29 × 104
3000 0.358 3.43 × 104
4000 0.477 4.57 × 104
5000 0.596 5.72 × 104
6000 0.715 6.86 × 104
6660 0.794 7.61 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 0.00441 106
3.00 0.00572 137
4.00 0.00763 183
5.00 0.00954 229
6.00 0.0114 274
7.00 0.0134 320
8.00 0.0153 366
9.00 0.0172 412
10.0 0.0191 457
20.0 0.0382 915
30.0 0.0572 1370
40.0 0.0763 1830
50.0 0.0954 2290
60.0 0.114 2740
70.0 0.134 3200
80.0 0.153 3660
90.0 0.172 4120
100 0.191 4570
200 0.382 9150
300 0.572 1.37 × 104
400 0.763 1.83 × 104
500 0.954 2.29 × 104
600 1.14 2.74 × 104
700 1.34 3.20 × 104
800 1.53 3.66 × 104
900 1.72 4.12 × 104
1000 1.91 4.57 × 104
1660 3.18 7.61 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 0.0223 238
3.00 0.0290 309
4.00 0.0386 412
5.00 0.0483 515
6.00 0.0580 617
7.00 0.0676 720
8.00 0.0773 823
9.00 0.0869 926
10.0 0.0966 1030
20.0 0.193 2060
30.0 0.290 3090
40.0 0.386 4120
50.0 0.483 5150
60.0 0.580 6170
70.0 0.676 7200
80.0 0.773 8230
90.0 0.869 9260
100 0.966 1.03 × 104
200 1.93 2.06 × 104
300 2.90 3.09 × 104
400 3.86 4.12 × 104
414 4.00 4.26 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 0.0705 423
3.00 0.0916 549
4.00 0.122 732
5.00 0.153 915
6.00 0.183 1100
7.00 0.214 1280
8.00 0.244 1460
9.00 0.275 1650
10.0 0.305 1830
20.0 0.611 3660
30.0 0.916 5490
40.0 1.22 7320
50.0 1.53 9150
60.0 1.83 1.10 × 104
70.0 2.14 1.28 × 104
80.0 2.44 1.46 × 104
90.0 2.75 1.65 × 104
100 3.05 1.83 × 104
131 4.00 2.40 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 0.172 661
3.00 0.224 858
4.00 0.298 1140
5.00 0.373 1430
6.00 0.447 1720
7.00 0.522 2000
8.00 0.596 2290
9.00 0.671 2570
10.0 0.745 2860
20.0 1.49 5720
30.0 2.24 8580
40.0 2.98 1.14 × 104
50.0 3.73 1.43 × 104
53.7 4.00 1.53 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 0.357 951
3.00 0.464 1230
4.00 0.618 1650
5.00 0.773 2060
6.00 0.927 2470
7.00 1.08 2880
8.00 1.24 3290
9.00 1.39 3700
10.0 1.55 4120
20.0 3.09 8230
25.9 4.00 1.07 × 104
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 1.13 1690
3.00 1.47 2200
4.00 1.95 2930
5.00 2.44 3660
6.00 2.93 4390
7.00 3.42 5120
8.00 3.91 5850
8.19 4.00 5990
Aluminum I Beam: 4.00 × 2.311 (4.00 inch tall × 2.311 lbf/ft)
L = 50.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
2.31 2.76 2640
3.00 3.58 3430
3.35 4.00 3840
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Mechanical Engineers Outlook

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

Negotiate Your Salary

Learn the best principles to negotiate the salary you deserve!

Metal 3D Printing Design Guide

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

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Optimize your designs, reduce machining time, and lower your costs.

more publications