Overview
A research project jointly undertaken by the fischer Group of Companies and Purdue University (USA) has demonstrated that existing reinforced‑concrete buildings in India can achieve significantly higher seismic resistance through targeted retrofitting measures. The study addresses the vulnerability of the vast pre‑code building stock that predates modern earthquake‑resistant design standards.
Test Methodology and Focus
The collaboration, led by Prof Akanshu Sharma (Associate Professor, Purdue University and former Endowed Professor at the Institute of Materials Science, University of Stuttgart), conducted large‑scale tests on full‑scale reinforced‑concrete structures. The primary focus was on beam‑column joints, identified as critical weak points that experience high stresses and horizontal forces during an earthquake. Dr Margaritis Tonidis, former PhD candidate at Purdue and project engineer, explained that failure of these joints can lead to total building collapse.
Retrofit Solution Details
The solution centers on installing haunch elements—specifically steel diagonal braces—directly into the existing structural framework. These braces are integrated using injection mortar and threaded rods, reinforcing the beam‑column joints on site. Dr Erik Johannes Stehle, Head of Development FiXperience at fischer, emphasized that the tests showed a marked increase in earthquake resistance when these critical points are identified and reinforced. The retrofit approach requires only minimal intervention, meaning occupants experience little disruption and no extensive alterations to the building’s interior.
Findings and Implications
Under simulated seismic loading, the retrofitted specimens displayed substantially improved performance, especially at the reinforced joints. The research validates a realistic, affordable pathway to enhance the resilience of older structures, offering a practical alternative to costly demolition and reconstruction. This approach can significantly reduce casualties in future seismic events.
Statements from Leadership
Mayank Kalra, Managing Director of fischer India, highlighted that India’s extensive building stock, much of which was constructed before current seismic design standards, makes the research especially pertinent. He noted that retrofitting critical structural points provides a sustainable solution that strengthens existing structures while minimizing disruption to occupants and preserving community resilience.
Global Seismic Context
The United States Geological Survey records approximately 500,000 earthquakes worldwide each year, with heightened risk in regions such as the Pacific Ring of Fire, the Mediterranean, the Himalayan belt, and Central America. Human activities like geothermal extraction, fracking, and large‑reservoir construction can also trigger seismic events.