The Role of Cooling on the Physical-Mechanical Response of Thermally Treated Jodhpur Sandstone: A Major Heritage Stone in India

Sandstone is a key material in many global heritage sites, including Jaisalmer Fort (Rajasthan), Petra (Jordan), and Angkor Wat (Cambodia). Its versatility makes it a popular building material, but environmental factors such as climatic conditions and fire incidents can cause significant damage. These factors can induce formation of microscopic changes, fissures, fractures, and intergranular porosity, leading to early failure. This vulnerability is of especial concern for heritage structures, where preserving the cultural and historical assets is critical task. In recent years, the frequency of fire incidents affecting heritage structures has increased such as the National Museum of Brazil fire in 2018, and the Notre Dame fire in 2019. Accurate assessment is crucial for developing effective remediation protocols for fire-damaged structures and ensuring the longevity of sandstone heritage sites globally. This study investigates the physical and mechanical properties of thermally treated Jodhpur sandstone, focusing on the role of cooling. The results demonstrate that various cooling methods, such as furnace cooling, air cooling, and water cooling, significantly influence the properties of sandstone. Specifically, the water-cooled specimens experienced the highest level of damage, characterized by the greatest decreases in density, uniaxial compressive strength (UCS), elastic modulus, and wave velocities. These findings underscore the importance of controlled cooling in heritage conservation, providing a scientific basis for improving preservation strategies for sandstone monuments exposed to thermal stress.