Optimal relaxation of stress concentrations in adaptive plates with holes using piezoelectric actuators

Piezoelectric actuators can induce various amounts of strain upon being activated. Therefore, it is possible to reduce the stress concentrations under various external load conditions by distributing piezoelectric actuators in region expected to be subjected to high stress before external load application. In this study, we treat the optimal relaxation of stress concentrations in adaptive plates with holes using piezoelectric actuators. Adaptive plate models are concerned with simple actuator/substrate systems in which the substrates are infinite isotropic plates with a circular hole, an elliptical hole or two circular holes of equal diameter, and actuators are bonded to the plate surfaces near the holes. To examine the performance of the adaptive plates, we calculate the optimal voltage that must be applied to each piezoelectric actuator to minimize the maximum stresses in the substrates under some external load conditions.