Answer Happy

Q7. Statically determinate or indeterminate truss analysis by the stiffness method (50 marks) a) Determine the stiffness matrix of the whole truss shown in Fig. 2 in the global co- ordinate system. Indicate the degrees-of freedom in all the stiffness matrices. Assume for each member AE = constant. (10 marks) b) Determine the stiffness matrices of elements 2, 3 and 4 in the local co-ordinate system and then convert the local stiffness matrices to the global co-ordinate system. Show all calculations. Check the results with those obtained in part a) above and comment. (15 marks) c) Calculate all the nodal displacements and all the member forces of the truss. (25 marks) 2 m 2 KN 2 2 m 90 Fig 7. Truss for Q7 1