Parametric analysis of thick plates subjected to earthquake excitations

Plates are structural elements commonly used in the building industry. A plate is considered to be a thin plate if the ratio of the plate thickness to the smaller span length is less than 1/20; it is considered to be a thick plate if this ratio is larger than 1/20. The purpose of this paper is to study shear locking-free analysis of thick plates using Mindlin’s theory and to determine the effects of the thickness/span ratio, the aspect ratio and the boundary conditions on the linear responses of thick plates subjected to earthquake excitations. Finite element formulation of the equations of the thick plate theory is derived by using second order displacement shape functions. A computer program using finite element method is coded in C++ to analyze the plates clamped or simply supported along all four edges. In the analysis, 17-noded finite element is used. Graphs and tables are presented that should help engineers in the design of thick plates subjected to earthquake excitations.