Elongation of bars due to axial loading

1. Elongation of simple bar
For prismatic bar area is constant along depth

Change in length (ΔL) = PL/AE
Here, P = pull applied
L = length of section
A = area of section
E = Young's modulus of elasticity of material

2. Elongation of stepped bar

Elongation ( Δ) =
(PL1/A1E) + (PL2/A2E) + (PL3/A3E)

3. Elongation of circular tapering bar

Elongation ( Δ) = (4PL/ πED1D2)

4. Elongation of composite bar

Elongation ( Δ) = [PL(A1E1+A2E2)]

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