Higher-order shear deformation of very thick simply supported equilateral triangular plates under uniform load

Abstract

ABSTRACTWhere deflections of thick plates are concerned, sufficient studies have been performed on circular and rectangular plates using first-order shear deformation theory (FSDT). Less attention, however, has been placed on the use of higher-order theories and plates of other shapes. This article proposes a deflection model for a simply supported and under uniformly loaded equilateral triangular plate that fulfils the third-order shear deformation theory (TSDT). Comparison of maximum plate deflections using this exact TSDT model with the FSDT and the simplified TSDT models reveals that the former exhibits better correlation agreement with the exact TSDT. Using the plate deflection from the exact TSDT, a refined shear correction factor, which is a function of Poisson's ratio, relative thickness, and location on plate, is extracted for the FSDT model. Results suggest that the usual shear correction model of 5/6 in Mindlin plates is highly accurate when dealing with moderately thick triangular plates made from negative Poisson's ratio materials, while the prescription of the refined shear correction factor obtained herein is advised for very thick triangular plates made from large Poisson's ratio materials. The results avail an FSDT deflection model for very thick triangular plates with the accuracy of exact TSDT.