Seismic Assessment and Retrofitting of Clay Brick Masonry Historical Structures of Northern India

Abstract

newline Historical clay brick masonry structures, particularly those constructed with lime surkhi mortar, are significant cultural and architectural assets, especially in regions like Punjab, India. Among the various historical sites, only thirty-three have been protected by the Archaeological Survey of India, while many others remain neglected and urgently need preservation, conservation, and maintenance. These structures, built over several centuries, are exposed to various environmental challenges and are at risk of deterioration, primarily due to their vulnerability to seismic forces. Southeastern Punjab, including cities like Fatehgarh Sahib, Patiala, Sangrur, and Ludhiana, seismically classified as a moderate risk level and comes in Zone III according to the IS 1893 seismic zoning map of India. Seismic events can inflict significant damage on these structures, which, while resilient to gravity loads, often lack the necessary capacity to withstand lateral forces from earthquakes. Given their historical and cultural importance, preserving these structures requires understanding their physical, mechanical and mineral properties. Additionally, developing effective retrofitting strategies is essential to preserve the structural integrity of these monuments for future generations.