Performance of limestone masonry walls under diagonal compression using innovative hybrid fiber-reinforced polymer (FRP) reinforcement techniques

This study investigates the in-plane performance of limestone masonry walls under diagonal compression by experimental and numerical analysis, focusing on innovative fiber-reinforced polymer (FRP) reinforcement techniques. The novelty of this research is the use of a hybrid reinforcement method combining wet lay-up CFRP and NSM GFRP. Twelve masonry wall specimens, including two unreinforced controls and ten reinforced with various configurations of carbon fiber-reinforced polymer (CFRP) fabric and glass fiber-reinforced polymer (GFRP) bars, two specimens for each wall configuration were subjected to diagonal compression tests. A detailed 3D micro-modeling approach using the finite element method was developed to simulate the behavior of masonry wall reinforced with hybrid method. The model, implemented in ABAQUS software, showed good correlation with experimental results in predicting maximum shear load, initial stiffness and failure modes. This research makes a valuable contribution valuable to improving the seismic performance of stone masonry structures, particularly in heritage contexts where minimal intervention is crucial. The results demonstrate significant improvements in shear strength and ductility across all reinforced specimens, with the hybrid configuration combining GFRP bars and CFRP fabric strips (M-1BTC) exhibiting the most substantial increase in shear strength, up to 276.60% compared to unreinforced walls. The study's findings and modeling approach offer practical solutions for enhancing masonry wall resilience against seismic hazards while preserving historical integrity.