고체역학 (Gere) — Axially Loaded Members: Problem 2.4-6

2.4-6 Three prismatic bars, two of material \(A\) and one of material \(B\), transmit a tensile load \(P\) (see figure). The two outer bars (material \(A\)) are identical. The cross-sectional area of the middle bar (material \(B\)) is 50% larger than the cross-sectional area of one of the outer bars. Also, the modulus of elasticity of material \(A\) is twice that of material \(B\). (a) What fraction of the load \(P\) is transmitted by the middle bar? (b) What is the ratio of the stress in the middle bar to the stress in the outer bars? (c) What is the ratio of the strain in the middle bar to the strain in the outer bars?