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The aim of this paper is finite element presentation for vibration response of the intelligent structure (consisting peizoeectric members) and modification of the response. The active element consists of a piezoelectric ceramic actuator stack, a force transducer and mechanical interfaces. An integral plus double-integral force controller is designed to suppress vibration of the truss. In this paper, in order to find the best piezoelectric operator’s location in spatial truss and optimizing the performance of the member by changing the property of the members, an algorithm is presented to achieve desired natural frequency. Therefore, finite element method of spatial truss is extracted. The results are admitted by ANSYS software. At the end, an example to show the application of the relations is given.

Thermal shock describes the way that a material exposed to a sudden change in temperature. These conditions usually take place in aerospace industry, when aircraft encounter the atmosphere layers. It also happens in combustion chamber of engines when mixture of fuel and air ignite in cylinder. Classical thermoelasticity is not capable to analyze such a problem. Therefore, generalized coupled thermoelasticity theories arose. In this article, the dynamic coupled thermoelastic response of a rectangular plate made of functionally graded material subjected to a thermal shock based on Lord-Shulman theory is studied. Using state space approach, the state equations of the problem are obtained. The plate’s boundary condition is simply support on the edges and the variation of mechanical properties is assumed to change along the thickness of the plate. The Laplace transform is applied to transform governing equations from time domain to the Laplace domain. Then by using a numerical method, the equations are solved and the results are inversed to the time domain displacement and temperature field are acquired. Results are presented for different power law indices and they are validated by previous reported literature.

In this paper, a dynamic analysis of annular laminate disk under radial thermal shock is carried out by employing a Galerkin Finite Element (GFE) approach. The governing equations, including the equation of the motion and energy equation are obtained based on Lord-Shulman theory. These two equations are solved simultaneously to obtain the displacement components and temperature distributions. A simply support boundary condition through outer edge is assumed for the annular disk. The inner radius is subjected to thermal shock and free of any traction. The outer edge is keeping at a constant temperature. Using Laplace transfer technique to transfer the governing equations into the space domain, where the Galerkin Finite Element Method is employed to obtain the solution in space domain. The inverse of Laplace transfer is performed numerically to achieve the final solution in the real time domain. The results are validated with the known data reported in the literature.