A three-dimensional stress recovery procedure for composite materials

A three-dimensional stress recovery procedure is described in this paper. As usual, in the finite element method, we suppose to know a good approximation of the nodal values of the displacements; starting from the nodal displacements, we evaluate the strain components at Gauss points of a 27-node prismatic element, then the stress components at the same points. Stresses are finally projected to corner nodes with a smoothing procedure. The repeated application of such a procedure to a set of adjacent elements allows the construction of the stress field in a finite region of any deformed body. The proposed method finds its most natural application in the field of composite materials as shown in the numerical applications which reveal a good concordance of results with an equivalent three-dimensional finite element analysis.