CNC Machining Design Guide

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

Injection Molding Design Guide

Guide for high quality and cost-effective plastic injection molding.

Metal 3D Printing Design Guide

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

3D Scanners

A white paper to assist in the evaluation of 3D scanning hardware solutions.

more free publications

Materials

Design

Processes

Units

Formulas

Math
Glossary » Beams » Simply Supported » Uniformly Distributed Load » Three Equal Spans » Aluminum I Beam » 3.00 × 1.637
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 = 2.24 in4) for the 3.00 × 1.637 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
   
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 3.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 6.85 × 10-5 11.8
2.00 8.37 × 10-5 14.5
3.00 1.26 × 10-4 21.7
4.00 1.67 × 10-4 28.9
5.00 2.09 × 10-4 36.2
6.00 2.51 × 10-4 43.4
7.00 2.93 × 10-4 50.6
8.00 3.35 × 10-4 57.9
9.00 3.77 × 10-4 65.1
10.0 4.19 × 10-4 72.3
20.0 8.37 × 10-4 145
30.0 0.00126 217
40.0 0.00167 289
50.0 0.00209 362
60.0 0.00251 434
70.0 0.00293 506
80.0 0.00335 579
90.0 0.00377 651
100 0.00419 723
200 0.00837 1450
300 0.0126 2170
400 0.0167 2890
500 0.0209 3620
600 0.0251 4340
700 0.0293 5060
800 0.0335 5790
900 0.0377 6510
1000 0.0419 7230
2000 0.0837 1.45 × 104
3000 0.126 2.17 × 104
4000 0.167 2.89 × 104
5000 0.209 3.62 × 104
6000 0.251 4.34 × 104
7000 0.293 5.06 × 104
8000 0.335 5.79 × 104
9000 0.377 6.51 × 104
1.00 × 104 0.419 7.23 × 104
1.05 × 104 0.441 7.61 × 104
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 5.00 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 5.29 × 10-4 32.9
2.00 6.46 × 10-4 40.2
3.00 9.69 × 10-4 60.3
4.00 0.00129 80.4
5.00 0.00161 100
6.00 0.00194 121
7.00 0.00226 141
8.00 0.00258 161
9.00 0.00291 181
10.0 0.00323 201
20.0 0.00646 402
30.0 0.00969 603
40.0 0.0129 804
50.0 0.0161 1000
60.0 0.0194 1210
70.0 0.0226 1410
80.0 0.0258 1610
90.0 0.0291 1810
100 0.0323 2010
200 0.0646 4020
300 0.0969 6030
400 0.129 8040
500 0.161 1.00 × 104
600 0.194 1.21 × 104
700 0.226 1.41 × 104
800 0.258 1.61 × 104
900 0.291 1.81 × 104
1000 0.323 2.01 × 104
2000 0.646 4.02 × 104
3000 0.969 6.03 × 104
3790 1.22 7.61 × 104
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 10.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 0.00846 132
2.00 0.0103 161
3.00 0.0155 241
4.00 0.0207 321
5.00 0.0258 402
6.00 0.0310 482
7.00 0.0362 563
8.00 0.0413 643
9.00 0.0465 723
10.0 0.0517 804
20.0 0.103 1610
30.0 0.155 2410
40.0 0.207 3210
50.0 0.258 4020
60.0 0.310 4820
70.0 0.362 5620
80.0 0.413 6430
90.0 0.465 7230
100 0.517 8040
200 1.03 1.61 × 104
300 1.55 2.41 × 104
400 2.07 3.21 × 104
500 2.58 4.02 × 104
581 3.00 4.67 × 104
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 15.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 0.0428 296
2.00 0.0523 362
3.00 0.0785 542
4.00 0.105 723
5.00 0.131 904
6.00 0.157 1080
7.00 0.183 1270
8.00 0.209 1450
9.00 0.235 1630
10.0 0.262 1810
20.0 0.523 3620
30.0 0.785 5420
40.0 1.05 7230
50.0 1.31 9040
60.0 1.57 1.08 × 104
70.0 1.83 1.27 × 104
80.0 2.09 1.45 × 104
90.0 2.35 1.63 × 104
100 2.62 1.81 × 104
115 3.00 2.07 × 104
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 20.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 0.135 526
2.00 0.165 643
3.00 0.248 964
4.00 0.331 1290
5.00 0.413 1610
6.00 0.496 1930
7.00 0.579 2250
8.00 0.661 2570
9.00 0.744 2890
10.0 0.827 3210
20.0 1.65 6430
30.0 2.48 9640
36.3 3.00 1.17 × 104
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 25.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 0.330 822
2.00 0.404 1000
3.00 0.605 1510
4.00 0.807 2010
5.00 1.01 2510
6.00 1.21 3010
7.00 1.41 3520
8.00 1.61 4020
9.00 1.82 4520
10.0 2.02 5020
14.9 3.00 7470
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 30.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 0.685 1180
2.00 0.837 1450
3.00 1.26 2170
4.00 1.67 2890
5.00 2.09 3620
6.00 2.51 4340
7.00 2.93 5060
7.17 3.00 5180
Aluminum I Beam: 3.00 × 1.637 (3.00 inch tall × 1.637 lbf/ft)
L = 40.0 ft
P (lbf/ft) w_max (in) stress_max (psi)
1.64 2.17 2100
2.00 2.65 2570
2.27 3.00 2920
Additional Information
Related Pages
FREE Publications
CNC Machining Design Guide

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

Injection Molding Design Guide

Guide for high quality and cost-effective plastic injection molding.

Metal 3D Printing Design Guide

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

3D Scanners

A white paper to assist in the evaluation of 3D scanning hardware solutions.

more publications