Enhancing Seismic Resilience of Soft-Storey Buildings through Optimized Reinforced Concrete Infill Solutions

Abstract

This research experimentally validates and establishes guidelines for optimizing the strengthening of reinforced concrete (RC) infill walls, focusing on local availability, response, price, usability, and difficulty. Two main objectives were pursued: (1) analyzing soft-storey frames using applied element method (AEM)-based numerical optimization to develop an effective strengthening solution, and (2) experimentally verifying the performance of the optimized RC infill wall in strengthening soft-storey buildings. The study found that the strengthening solution significantly enhanced structural performance, with the maximum peak load increasing from 7 kN for the soft-storey frame to 73 kN for the strengthened frame, a tenfold increase. The strengthened frame also dissipated energy five times better than the soft-storey frame, demonstrating superior seismic energy absorption. Substantial displacements at the ground floor were mitigated in the strengthened frame, improving stability and stiffness. The strengthened frame's stiffness was about ten times higher than that of the soft-storey frame, attributed to added curves connecting the columns and beams on the ground floor. Additionally, the strengthened frame's natural frequency was 25.62 Hz, lower than the predicted 30.55 Hz, likely due to construction variations. These results highlight the efficacy of the proposed strengthening method in enhancing the seismic resilience of soft-storey buildings.