Abstract: For the piezothermoelasticity intelligent thin plate, a cube finite element model including 4 displacement nodes, 2 electric potential nodes and 8 temperature nodes is presented, its displacement field is defined by means of the plane shell element model, and its electric potential field and temperature field are both defined by means of linear interpolation. The finite element equations are deduced by applying the virtual work principle. When parameters are random and the moment method is used to obtain response’s numerical characteristics, in order to avoid the difficulty of sensitivities computation on the response’s analytical solution, the finite element equations are translated to state equations, and the sensitivity differential equations are obtained from the derivative of state equations. Then, the sensitivity at each discrete time is obtained by making use of the deference method. An intelligent cantilever plate is taken as an example, and the numerical results show that the computing process presented has good precision and fast calculation speed.

Key words: piezothermoelasticity, finite element method, deference method, moment method, Monte Carlo method