Control of stress concentration using bonded piezoelectric actuator and composite patch in aluminium structure

In fracture mechanics, material failure can occur when the applied load is directly proportional to the maximum stress region or stress concentration point. In this study, a finite element analysis was conducted to investigate the reduction of stress concentration factors in aluminum plates with a central hole using various repair strategies. The repair configurations included single- and double-sided bonded composite patches, piezoelectric actuators with varying electric fields, and hybrid systems combining both techniques. The analysis was performed under uniaxial tensile loading to evaluate the performance of each method. A detailed parametric study of the bonded repair system was conducted, and the stress distribution in the optimized repair configuration was evaluated. Results showed that the double-sided composite patch reduced the SCF by approximately 55.67%, while the hybrid configuration (composite patch and actuator with an electric field of 1.0) achieved a 56.99% reduction. The greatest improvement, a 60.67% reduction, was observed in the fully active system with piezoelectric actuators on both sides. The findings demonstrate that electric field intensity plays a critical role in enhancing repair performance and that actuator-based active repair outperforms passive patching. These results provide insights into the development of advanced structural control strategies in aerospace and mechanical systems.