| At present, it is brand new and challenging for the research of piezoelectric intelligent structure. Existing research is mainly about vibration control and deformation control. Many explore for other aspects are depended on development. For piezoelectric structure system, there are a lot of stochastic factors, for example,the load which act on the structure are indeterminate; material data and dimension data provided may be not completely consistent with that of real structure; Therefore, it is necessary to make stochastic analysis of piezoelectric structure and evaluate its reliability. The present thesis has made some progress in this field, statics reliability analysis, stabile reliability anlysis and dynamic reliabilityansyis are investigated.The main research works of the theis are as following:1. For the struss structure comprised of piezoelectric actuator element, the finite element model is derived and developed, which comprises statics model,stabile model and danymic model. The responses of internal force under Mech-Electric compling are acquired.2. To research the failure mechanism of the piezoelectric material. In the process of statics and danymic reliability analysis,the failure criterion of the piezoelectrics actuator is proposed, based on which, safety margin functions of failure mode are established which is caused by fracture damage or electrical breakdown. In the process of stabile reliability analysis, safety margin functions are establishede which is composed of load coefficient.3. Considered the material fracture strength, breakdown electric field intensity, area of section and load as stochastic variables, Taylor expansion SFEM is adopted to get partial derivative of the safety margin functions , and then reliability of structure systems is analyzed. The riability index of structure system is acquired by PNET.4. A lot of calculation procedures are written to solve examples and to analysis the effects of Mech-Electric compling to the reliability index.
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