Membrane stress calculates the stresses along the thickness of the shell in longitudinal direction, in transverse direction, and in plane shear. The result is available only for shell bodies and solids that are meshed using the thin-solid meshing option. Each element of the body can display individual stress values and give a checkboard appearance to the result contours. The results are calculated in the element coordinate system.

Shell membrane stress tensor (s11m, s22m, s12m) is the average of the in-plane stress tensor (s11(z), s22(z), s12(z)) along the shell thickness direction:

Where:

Unlike linearized stress in other elements, a pre-defined path through the shell thickness is not required in order to compute shell membrane stress.