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 be made significantly more earthquake‑resistant through targeted retrofitting measures. The study focused on the critical beam‑column joints of RC frame structures, which experience the highest stresses during seismic events.
Project Leadership and Participants
The project was led by Prof Akanshu Sharma, Associate Professor at Purdue University and former Endowed Professor at the Institute of Materials Science, University of Stuttgart. Dr Margaritis Tonidis, a former PhD candidate at Purdue and the project’s lead engineer, explained the vulnerability of these joints, while Dr Erik Johannes Stehle, Head of Development FiXperience at fischer, highlighted the test outcomes.
Technical Solution
The retrofitting approach introduces haunch elements—specifically steel diagonal braces—into the existing structural framework. These braces are installed on‑site using injection mortar and threaded rods, reinforcing the beam‑column joints with minimal alteration to the surrounding structure, thereby avoiding extensive disruption for occupants.
Test Results
Full‑scale seismic loading tests on reinforced‑concrete specimens showed a marked improvement in performance, particularly at the reinforced joints. The tests confirmed that the earthquake resistance of existing buildings can be significantly increased when critical load‑bearing points are identified and strengthened.
Global Seismic Context
According to the US Geological Survey, approximately 500,000 earthquakes are recorded worldwide each year, with heightened risk in regions along the Pacific Ring of Fire, the Mediterranean, the Himalayas, and Central America. Human activities such as geothermal extraction, fracking, and large‑reservoir construction can also trigger seismic events.
Implications for India
India possesses a vast building stock, many structures having been constructed before modern seismic design standards were introduced. Demolishing and rebuilding these structures is deemed unrealistic due to cost, time, and resource constraints. Retrofitting, as demonstrated by the fischer‑Purdue research, offers a practical, affordable, and sustainable alternative that can enhance structural resilience while minimizing disruption to occupants.
Executive Commentary
Mayank Kalra, Managing Director of fischer India, stated that the research is especially relevant for India given its vulnerability to earthquakes across several regions. He emphasized that retrofitting critical structural points can strengthen existing buildings, protect lives, and contribute to safer, more resilient communities.