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The membrane nodal resultants of a shell are concentrated forces Fx and Fy (with force units) at the four nodes of each shell element.  They in effect keep each individual element in equilibrium (in-plane).  They are expressed in the local coordinate system.

 

You may view nodal forces of selected shell elements by Quick Access Toolbar > Annotate.  The membrane nodal forces may be used to compute shears, axial forces, or moments in a shear wall. For example, the following three shells represent a pier in a shear wall.  Each shell is 1.5 x 1.5 ft in size.  Membrane nodal resultants Fx and Fy are shown in the first and second rows respectively at each corner of the element.  The shear, axial force and moment resultants on the top of the pier may be computed as follows: