BIAXIAL LOADING ANALYSIS OF LAMINATED POLYMER COMPOSITE MATERIAL

Abstract

The contemporary practice of using uniaxial tests as a source for failure prediction of composite materials
which are inhomogeneous and anisotropic under multi-axial loading has witnessed to be inadequate. Therefore, biaxial and
multi-axial tests appeared obligatory to improve our understanding the behavior of these complex materials. The present
paper is focused on selection of suitable geometry for the test coupons required under biaxial loading.
The specimen with: 1. Uniform stress about the gauge section, 2. Failure in the gauge section and 3. Preventing the
undesired non-uniform strain distribution due to stress concentration is selected. FEA is implemented on the cross shape (╬)
specimen with different undercuts and holes with different stress ratios ranging from (σx:σy) = 1:1, 1:0.5, 1:0.75, 1: -0.25, 1:-
0.5, 1:-0.75 are applied on the four edges of the specimen for selection of suitable geometry.