All elements of the structure in Figure P3?47 have the same AE except element 1, which has an axial stiffness of 2AE. Find the displacements of the nodes and the stresses in elements 2, 3, and 4 by using symmetry. Check equilibrium at node 4. You might want to use the results obtained from the stiffness matrix of Problem 3.24.

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Reference Problem 3.24

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Determine the nodal displacements and the element forces for the truss shown in Figure P3?24. Assume all elements have the same AE.

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P 2 6 20 ft Figure P3-47 P 3 0 7 (10) 20 ft (10) 5 15 ft 8