Determination of the longitudinal non linear elastic behaviour and compressive strength of a CFRP ply by bending tests on laminates

摘要

A method for extracting the axial non linear elastic behaviour and compressive strength of unidirectional plies from bending tests on carbon fibres laminates is proposed. It is first based on a procedure using the axial elastic non linearity to describe the observed shift of the neutral axis position during loading. This procedure extracts four axial elastic parameters by identification. It is validated via numerical analyses. The compressive strength is then calculated and lower values (similar to 15%) than those obtained by ignoring these elastic non linearities are found. This emphasises the necessity of using such a method to get proper elasticity description and compression strength values for the design of composite structures.