The stepped bar shown is loaded axially with a force of 45 k

The stepped bar shown is loaded axially with a force of 45 kip. Given the dimensions D = 4.50 in, d = 3.00 in. r = 0.63 in, t = 0.375 in Determine: What is the stress concentration factor for the geometry shown? What is the maximum stress in the bar?

Solution

Stress concentration factor due to geometry K_t can be found from the graph.

K_t = 1.75

Nominal stress in the bar = Force applied / cross-sectional area

Stress = 45 / ( 3 x 0.375) = 40 kpsi

Actual stress = Stress concentration factor x Nominal stress

= 1.75 x 40

= 70 kpsi