Problem # p007

Axial stresses, statically indeterminate

    In the figure to the left a rod is installed in between two walls and anchored solidly into each wall. The distance between the walls will remain at L for good. The rod is made out of two sections, length L1 and L2, respectively. Both sections have the same cross-section, A, and same Young's modulus E. Initially the entire rod is stress free but then load P, acting exactly at the intersection between the two sections, is applied.

Question

Derive the equations for the two forces, F1 and F2 in the above figure, which each of the stationary walls exert onto the rod.

Evaluate and comment on your equations for the three cases :

  1. L1 = 0
  2. L1 = L2
  3. L2 = 0