MATHEMATICAL MODELLING OF DELAMINATION IN COMPOSITE PLATES

Abstract

The use of fiber reinforced plastic composite materials in the field of aerospace, naval architecture, mechanical engineering and also in infrastructure application such as civil engineering is expanding very fast. Delamination is one of the predominant forms of failure in laminated composites due to the lack of reinforcement in the thickness direction. Delamination as a result of impact or a manufacturing defect can cause a significant reduction in the load carrying capacity of a structure. The simulation of the delamination process of FRP composite laminates is quite complex, and requires advanced Finite Element modelling techniques. The aim of the present study is mathematical modeling of delamination of fiber reinforced plastic laminated composite plates. This is presented in a simple and computationally efficient, adaptive finite element analysis using general purpose computer software ANSYS. A computational finite element model of the delamination problem of fiber reinforced composite laminate has been presented and validated by comparing the obtained results with the existing literature. ANSYS has been adopted for accurate and reliable evaluation of delamination of fiber reinforced composite laminate and normal and shear traction stresses of the interface in FRP composite laminates subjected to controlled displacement as loading. Studies have clearly shown the importance of appropriate finite element mesh for reliable prediction of delamination initiation and growth. A good number of cases have been considered with varying stacking sequences, height to length ratio, width to length ratio, material properties, maximum normal traction and normal separation values, and number of plies. The model clearly shows the increase of normal traction stress to the maximum normal traction stress value given and the decreases to zero with the growth of delamination.