Evaluation of Shear Deformation Plate Theories of Composite Laminates

Abstract

The structural theories used to model the global behavior of laminated composite plates fall into the category of “equivalent single layer (ESL) theories”. In these theories, the material properties of the constituent layers through the thickness are “smeared” to form an equivalent single layer plate. The present study deals with an evaluation of various ESL theories, including the third-order shear deformation theories, in predicting global response characteristics of composite laminates. In this work, all commonly used, displacement-based theories are unified as special cases of the general third order theory developed by Reddy [1,2] with the introduction of “tracers”. The equations of motion, analytical solutions, and finite element models have been derived for the unified theory, and the other theories simply fall out from this by proper assignment of tracers. Due to the space limitation, details of the theoretical development are omitted and only few representative results are presented here.