Hygrothermal effect on dynamic interlaminar stresses in laminated plates with piezoelectric actuators

Hygrothermal effect on the response histories and distribution of dynamic interlaminar stresses in laminated plates with piezoelectric actuator layers, under free vibration are studied, based on a hygrothermoelectrodynamic differential equations. The material properties of composite are determined according to a micro-mechanical model of a laminate. The stacking sequence of laminated plates may be arbitrary. The hygrothermal loads are considered as a linear function of coordinates in planes of each layer and the electric field is considered as the transverse component Ez only. The interlaminar stresses are obtained by integrating the 3-D equations of dynamic equilibrium, and utilizing given boundary conditions and continuity conditions of stresses between layers. The numerical illustrations concern the response histories and distribution of interlaminar stress in the laminated plates with different fiber volume and fully covered or embedded piezoelectric actuators, under different sets of environmental conditions and electric excitation. The theoretical analyses and results are of certain significance in practical engineering application.