ENCI 451 Study Guide - Final Guide: Virtual Work, Elastic Modulus, Delaware Route 1

• School: University of Calgary
• Department: Civil Engineering
• Course: ENCI 451
• Professor: T.G.Brown

Document Summary

Random virtual work example november 15, 2012. Given the truss in the figure above, find the forces in all the members. This is a simple truss, so the force method is sufficient enough to solve this problem. Step 1: find i, the degree of static indeterminacy or degrees of freedom. Two ways to do this: inspection 2 cross braced sections means i = 2, calculation: Hence two forces releases are needed, so remove the diagonal members hb and hd. Step 2: find the displacements {d} due to the released structure. The axial displacement of a truss member using virtual work is given in the textbook as: Nuj = the member forces of the truss due to a virtual unit load at coordinate j, N = the member forces of the truss due to the released structure (hence, the two diagonal members we removed should not exist in the truss), l = length of each truss member.