Question

Use FEA (computations by hand) to analyze the space truss below: The truss is composed of four nodes, whose coordinates (in inches), and three elements with cross-sectional areas given in the Figure. The modulus of elasticity (for all elements) is E-1.2x10. A load F-1000 lbf is applied at node lin the negative z-direction. Nodes 2,3, and 4 are supported by ball-and-socket joints and thus constrained from movement in the x,y, and z directions. Node 1 is constrained frommovement in the y-direction by the roller. For clarity, additional pertinent information is given in the Table below: j L, in е (0, 36, 72) сх су cz 1 1 2 80.5 -0.89 0.45 0 A) 0.302 in. A 0.729 in.2 2 3 -0.667 108 0.33 0.667 A) 0.187 in.2 3 1 4 86.5 -0.833 0 -0.55 Determine: (0, 36, 0) (a) displacement components of node 1 (b) support reactions (c) stress in each element Roller preventing y displacement (72, 0, 0) (0, 0,-48)

Answer 1

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Calulate imilar manner e 049.46 Lb 40 pei1ension 2850 psi (ompuasim