This page provides data for area, weight per unit length, moment
of intertia, Section Modulus, Radius of Gyration and centroid
location for round tube members.
wa = weight per foot of aluminum tubing, lb ws = weight per foot of steel tubing, lb A = area, in^2 I = moment of inertia, in^4 k = radius of gyration, in Z = section modulus, in^3 Size wa ws A I k Z ----------- ----- ------ ----- ----- ----- ----- 1 x 1/8 0.416 1.128 0.344 0.034 0.313 0.067 1 x 1/4 0.713 2.003 0.589 0.046 0.280 0.092 1-1/2 x 1/8 0.653 1.769 0.540 0.129 0.488 0.172 1-1/2 x 1/4 1.188 3.338 0.982 0.199 0.451 0.266 2 x 1/8 0.891 2.670 0.736 0.325 0.664 0.325 2 x 1/4 1.663 4.673 1.374 0.537 0.625 0.537 2-1/2 x 1/8 1.129 3.050 0.933 0.660 0.841 0.528 2-1/2 x 1/4 2.138 6.008 1.767 1.132 0.800 0.906 3 x 1/4 2.614 7.343 2.160 2.059 0.976 1.373 3 x 3/8 3.742 10.51 3.093 2.718 0.938 1.812 4 x 3/16 2.717 7.654 2.246 40.90 1.350 2.045 4 x 3/8 5.167 14.52 4.271 7.090 1.289 3.544 ----------- ----- ------ ----- ----- ----- -----