Postbuckling analysis of variable angle tow composite plates under shear load

A geometrical nonlinear analysis of a symmetric, variable angle tow (VAT), composite plate structure under inplane shear load is investigated in this work. The nonlinear von- Karman governing differential equations (GDEs) based on stress function and displacement function are derived for postbuckling analysis of symmetric VAT plate structures. A numerical methodology based on the differential quadrature method (DQM) is developed for solving the GDEs of VAT plates. The methodology is applied to solve the postbuckling problem of VAT plates with linear fibre angle orientations under simply supported plate boundary conditions. To show the accuracy and robustness of DQM, results are compared with commercial finite element analysis. The postbuckling behaviour of VAT plates under positive and negative shear is studied for different VAT fibre orientations, aspect ratios and their performance is compared with straight fibre composites. In addition, the influence of the direction of shear on the postbuckling behavior of VAT plates under axial compression is studied.