Sign Convention of Element Forces
General sign conventions of element forces
Bending moments Mx and My
Mx is the Bending moment on the local x face. the local x-face is the face perpendicular to the local x-axis.
My is the Bending moment on the local y face. the local y-face is the face perpendicular to the local y-axis.
Stress caused by Mx
Stress caused by My
Stress caused by Torsion (Mz)
Membrane stresses Sx and Sy
In plane shear stresses Sxy and Syx
