Isogeometric static analysis of laminated plates with curvilinear fibers based on Refined Zigzag Theory

In this study, we propose a new IsoGeometric formulation based on Refined Zigzag Theory (RZT), abbreviated as IG-RZT, for static analysis of laminated plates and sandwich panels with curvilinear fiber paths the first time in literature. The original RZT defines constant, linear, zigzag deformation contributions thickness coordinate to in-plane displacements. This kinematic relation can accurately predict displacement composite straight fibers. However, estimating realistic variation displacements variable angle tow (VAT) is more challenging problem compared composites. difficulty has been addressed herein by including quartic (fourth-order) polynomial expansion that includes transverse normal strain effects fields RZT. Moreover, modelling VAT composites results functions depend not only but also positions. present IG-RZT methodology free shear-locking shear correction factors due integration Non-Uniform Rational B-Splines (NURBS) isogeometric analysis. use NURBS enable exact geometry data be taken directly from computer aided design (CAD) software, e.g., Rhinoceros, into an in-house Mathematica code. accuracy efficiency assessed validated solving various examples different aspect span-to-thickness ratios. Comparison reference solutions available literature generated commercial software (ANSYS) using 3D finite elements have demonstrated remarkable benefits proposed method predicting highly accurate both stress distributions structures.