MULTIPLE CRACK DAMAGE DETECTION OF STRUCTURES USING SIMPLIFIED PZT MODEL

A novel damage identification scheme for multiple cracks in beams is presented based on the one-dimensional (1-D) piezoelectric patch with beam model. A hybrid element constituted of a 1-D beam element and a PZT sensor is used with reduced material properties. This model is more convenient and simpler for crack identification of beams than using a complex 3-D patch model. The hybrid beam element and the multiple crack identification procedure is verified experimentally. The crack identification is carried out as an inverse problem whereby location and depth parameters are identified by minimizing the deviation between the predicted and measured voltage responses of the patch when subjected to excitations. In the proposed method, a patch is attached to either end of the fixed beam. The numerical and experimental results show that there is significant improvement in identification accuracy compared to other methods.