Instructions:

This assignment is to learn how to analyze structures using commercial software "ETABS" which is available at a computer lab in KU$.$

You should show all steps of your work in detail.

Do not copy any other solutions. If you copy your solutions from others, it will result in $30\%$ reduction of your mark.

$20\%$ reduction in late submission.

Use A$4$ Sheet.

Answer the below two questions. The results of ETABS simulations must be included via a screen capture or any other ways.

Question #$2(50$ marks$)$: Truss Analysis

Assume the joint $(4)$ is pin$-$supported and the joint $(2)$ is free to move in the x direction and fixed in the y$-$direction like a roller support. Consider the joint $(1)$ as the origin of the global coordinate system. Assume AE is a constant.

a$)(30$ marks$)$ Determine the reactions at all the supports and the force in each member using ETABS?

b$)(20$ marks$)$ Compute the reactions at all the supports and the force in each member using the direct stiffness method and compare them with the results of a$)?$