A cell-based smoothed three-node Mindlin plate element (CS-FEM-MIN3) based on the C0-type higher-order shear deformation for geometrically nonlinear analysis of laminated composite plates

A cell-based smoothed three-node Mindlin plate element (CS-FEM-MIN3) based on the first-order shear deformation theory (FSDT) was recently proposed for static and free vibration analyses of Mindlin plates. In this paper, the CS-FEM-MIN3 is extended to geometrically nonlinear analysis of laminated composite plates. The nonlinear formulation is based on the C0-type high-order shear deformation plate theory (C0-HSDT) and the von Kármán strains, which deal with small strains and moderate rotations. In the process of formulating the system stiffness matrix of the CS-FEM-MIN3, each triangular element will be divided into three sub-triangles, and in each sub-triangle, the MIN3 is used to compute the strains. Then the strain smoothing technique on whole the triangular element is used to smooth the strains on these three sub-triangles. The accuracy and reliability of the proposed method is verified by comparing its numerical solutions with those of available other numerical results.