Numerical and Experimental Analysis to Predict the Compressive Strength of Pristine Composite Laminates

Abstract

In this work, the numerical and experimental work has been carried out to verify the compressive strength of pristine composite laminates. Theoretical computations have been carried out using MATLAB to compute the strength and buckling load. Finite Element Analysis has been carried out for the composite laminate using two and three dimensional elements. PATRAN as the Pre and Post processing package and NASTRAN as the solver have been used in this work. The various failure theories considered in this article are Tsai-Wu, Hill, Hoffman, Maximum Stress and Quadratic failure theory (YSFT). All the first four failure theories are available as a standard criterion in the PATRAN package. The fifth quadratic failure criterion has been implemented using PATRAN Command Language. Static analysis along with failure theories has been carried out to compute the strength of the laminate. Static and buckling analysis has been presented for both in two-and three-dimensional models. Experiments have been carried out on number of pristine laminates and the strain values obtained from FEA have been compared with the experimental values. The theoretical computation provides a load value which is about the elastic limit of the specimen. It is generally observed that quadratic failure theory (YSFT) provides least failure indices and may be employed for conservative design.