mechanics of materials part 2

1. Normal and Shear stresses on inclined sections
b
c
ϴ
A
P
2D view of the normal section
(thickness perpendicular to the
page)
2D view of the inclined section
Stress

2. The force P can be resolved into components:
Normal force N perpendicular to the inclined plane, N = P cos θ
Shear force V tangential to the inclined plane V = P sin θ

3. If we know the areas on which the forces act, we can
calculate the associated stresses.
Stress

4. A prismatic bar having cross-sectional area A=1200mm2 is compressed by an
axial load P=90KN. Determine the stress acting on an inclined section pq cut
through the bar at angle ϴ = 250
Stress
Example