Nonlinear Stability Analysis of Imperfect Three‐Phase Double Curved Shallow Shell Integrated With Magneto‐Electro‐Elastic Face Sheets

ABSTRACT

This paper investigates the nonlinear buckling and post‐buckling behaviors of geometrically imperfect double curved shallow sandwich shells subjected to axial compressive loading and uniformly distributed transverse load in a thermomechanical environment. The sandwich shell consists of a three‐phase composite (TPC) core integrated with magneto‐electro‐elastic (MEE) face sheets. The homogenized effective properties of the TPC core are analytically evaluated based on the volume fractions of the constituent polyester matrix, reinforcing fibers, and particles, while explicitly accounting for the interaction between the matrix and particles, as well as the subsequent interaction between the matrix reinforced with particles and the reinforcing fiber. The coupled system of governing equations is formulated within the framework of Reddy's first‐order shear deformation shell theory (FSDT), integrated von Kármán‐type geometric nonlinearity, initial geometric imperfections, thermal effects, and elastic foundations. Parametric studies are carried out to evaluate the effects of particle volume fraction, fiber volume fraction, geometric parameters, initial imperfection, and elastic foundation stiffness parameters on the critical buckling loading, thermomechanical post‐buckling response, and load‐carrying capacity. The results reveal that the nonlinear stability response is highly sensitive to these parameters, providing useful insights for the design of advanced smart sandwich structures.