The Indian heritage monuments are unique by the use of indigenous materials and intricate construction techniques. More than 80% of the built heritage in India are masonry structures in either brick or stone. Though they have survived over centuries, they are vulnerable to weathering actions of wind, salt and moisture, especially the structures along the coastal area. The incompatibility issues of replacing ancient lime mortar with cement mortar or mortars with other modern materials have been established recently through many case studies and research. The incompatibility generally arises between the physical, chemical, or mechanical properties of the ancient and new repair materials. The sacrificial nature of historic mortars is attributed to the excess interconnected porosity and lesser strength compared to the substrate masonry unit. Moreover, porosity and rigidity are the significant factors governing the design of repair mortar. Hence, in addition to the mechanical strength, stiffness, and bond strength, resistance to salt weathering is also critical to the durability of a masonry structure, especially for those near the coastal regions. Considering the adversities in using cement as repair mortar in masonry structures, lack of standardization and extremely longer slaking time requirement of lime mortar and the non-standardized use of organic additives, it is essential to investigate the possibilities of novel formulations which can cater to the requirements.
My research focuses on investigating the salt weathering resistance of bricks, and mortars, thereby formulating repair mortar compositions with functional, aesthetic and physical compatibility with the parent materials. Consolidants are usually applied to improve the cohesion between the grains and, thereby the mechanical properties of the substrates. I investigate the effectiveness of consolidants in the salt weathering resistance of mortars, brick and brick-mortar sandwiches.