Page 71 - Fundamental of Engineering Design
P. 71
Direct stress in the round bar
◦ Figure below shows a bar of constant cross-sectional
area A. The end of the bar carry uniformly distributed
normal loads of intensity p. We know from static that:
when the loading is uniform, its resultant passes through
the centroid of the loaded area
◦ Therefore the resultant P=Σp of each end load acts P
along the central axis of the bar. In the case of p
uniform loading the internal forces acting on all cross Area= A
sections are also uniformly distributed.
p
◦ Therefore, the normal stress acting in any point on a
cross section is
σ = 71
