Failure analysis of composite laminates subjected to hydrostatic stresses: A multicontinuum approach

Triaxial failure analysis using multicontinuum decomposition has been employed at the constituent level to predict nonlinear damage behavior and failure envelopes, all involving through-thickness stresses. In addition, a structural analysis algorithm is presented and is found to be numerically highly efficient in that the relationships between composite properties and damaged or failed constituent properties are completely determined prior to structural analysis. As a part of the Second World-Wide Failure Exercise, three-dimensional failure envelopes and stress–strain curves involving isotropic materials as well various unidirectional and multi-directional materials are presented for 12 test cases requested by the organizers. The present paper provides new developments in the multicontinuum methodology including: (a) modification of the constituent failure criteria, (b) incorporation of pressure effects, (c) new damage analyses, and (d) implementation into a commercial finite element package. Correlation with experimental results is provided in a second article addressing Part B of the Second World-Wide Failure Exercise.