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

Lin Htin1

Kishor Timsina2

Chaitanya Krishna Gadagamma1,3

Qudeer Hussain4

Ali Ejaz5

Panumas Saingam6

Wasim Khaliq5

Gritsada Sua-iam6

Burachat Chatveera7

Zabihullah Dalil Shinwari8

Kriti Shrestha9

Suniti Suparp10,11,Email

1Structural Engineering, School of Engineering and Technology (SET), Asian Institute of Technology (AIT), Klong Luang, 12120, Thailand

2Madan Bhandari University of Science and Technology (MBUST), Thaha-09, Chitlang, 33300, Nepal

3Department of Civil Engineering, Chennai Institute of Technology, Chennai, 600036, India

4Department of Civil Engineering, Kasem Bundit University, Bangkok, 10250, Thailand

5 National Institute of Transportation, National University of Sciences and Technology (NUST), Islamabad, 44000, Pakistan

6Department of Civil Engineering, School of Engineering, King Mongkut's Institute of Technology, Ladkrabang, Bangkok, 10520, Thailand

7Department of Civil Engineering, Faculty of Engineering, Thammasat University (Rangsit Campus), Pathum Thani, 12121, Thailand

8Faculty of Engineering, Kardan University, Kabul, 1001, Afghanistan

9Gautam Buddha International Airport, Kathmandu, 44600, Nepal

10Department of Civil and Environmental Engineering, Faculty of Engineering, Srinakharinwirot University, Nakhonnayok, 26120, Thailand.

11Center of Excellence in Rail System Technology and Civil Engineering Material Innovation for Sustainable Infrastructure, Strategic Wisdom and Research Institute, Srinakharinwirot University, Bangkok, 10110, Thailand

 

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.