M PS #9 Read sections 5-8, 5-9, chapter 5 summary, 6-8, and 7-16 and complete the following problems. 1. A 3.0 x 1.5m sign is supported by a hollow circular column, which has a 100mm outside diameter and 75mm inside diameter. A wind pressure of p=0.75kN/m is evenly distributed across the sign area (blowing in the negative z direction). Neglect the weight of the sign and column. a. Find the state of stress at points B and D on the outside surface of the column. Find the principal stresses and directions and maximum shear stress b. c. Draw the principal stress on a stress element including the original axes 2 1.5m 5.25m 3m