Finite Element Results - Bending Stresses
The bending stresses are the surface stresses within the element that are caused by the bending moments alone, and the shear stresses at the mid-thickness plane of the element caused by the shear forces.
The surface stresses printed are for the top surface of the shell; and are given by:
The surface stresses for the bottom surface are of course of opposite sign.
A positive stress denotes compression.
It is assumed that the magnitude of the out-of-plane shear stress varies parabolically through the thickness of the shell, and that there is no shear stress at the surface. Hence the shear stress at the mid-thickness plane is given by:
where:
σzx and σzy denote the shear stress in the local zx and zy planes respectively.