Question

For a 6x4 x5/8 unequal leg angle locate the centroid relative to the axes shown below (the U and V axes in the figure), and then find the maximum and minimum mlues for the moment of inertia with respect to the centroidal axes. The centroidal axes are located at the centroid, but the axes associated with the maximum and minimum moments of inertial (the principle moments of inertia) are not parallel to the U and V axes shown below. Find the radius of gyrations associated with the maximum and minimum values of the moment of inertias, as well as the orientation of the maximum moment of inertia. Ignore fillets and rounds in your computations You should consult your text books from ESC 201 and ESC 2 6.00 4.00 If the angle above was half of a double angle section with long legs back to back (2L LLBB) find the value of the section modulus with respect to the horizontal centroidal axis.

Answer 1

In cases of L section, centroid of the section is positioned outside the section. Principal axes are rotated about the centroid. So the horizontal and vertical axes are no more the principal axes. All the calculations must be done keeping this in mind.

u. u/ =2.03 T0-62.5 石0.92 niviaing the ale int

depth ot ecto ind cen ta 3-2,03)2 400.6s X 0,615 X (2 00,62512 = 14.77+629 21.06 1.5 t-4,4 b 5.96