From  the enlarged view of the linear variation of normal stress s, we see that s  varies from zero at the beam’s neutral axis to a maximum value, s_max, at a distance farther from the neutral axis.

s = -(y/c)smax

smax = Mc/I

s = -My/I

   Here,

s_max = the maximum normal stress in the beam.

I = the moment of inertia of cross sectional area computed about the neutral axis

M = the resultant internal moment, determined from the method of section and the equilibrium, and computed about the neutral axis of cross section

c = the perpendicular distance from the neutral axis to a point farthest away from he neutral axis, where s_max acts.

y = the distance far away from neutral axis.

top