Material properties of the light mass bricks from an 800 year old Heritage site in India

Restoration and preservation of Heritage Structures in any country is a challenging task and sometimes requires urgent attention. Moreover, it is important for sustenance of culture and heritage of the society. But many times, it is very difficult to find matching materials used in the past and hence due to use of available cementitious materials there can be degeneration of existing material. In view of this, there is a need to characterize these ancient materials and develop alternate materials with almost similar characteristics. With this knowledge, an alternate material similar in mineral composition and physical properties need to be developed, which will not have compatibility issues during and after repair. In the present study, the material characterization of an ancient floating brick at an Indian Heritage site was examined using modern analytical techniques like SEM-EDS, XRD and FTIR. In addition, the physical properties like specific gravity, bulk density, voids ratio and porosity were also determined. From the analysis, it could be confirmed that the bricks were light in weight due to the pores content and could float in water due to the non-interconnected porosity. Also, the presence of quartz, alumina and hematite from SEM-EDS analysis confirmed that these bricks were made of firing the clay, at lower temperatures, to induce pores. This low temperature firing of clay was supported by FTIR analysis indicating the presence of Si-O bond that would have disappeared at higher temperature.

Automated summary

The characterization of ancient materials and development of alternative materials with similar properties is crucial for preserving cultural and heritage sites. A study on floating bricks at an Indian heritage site revealed that the bricks were made of clay fired at low temperatures, explaining their lightweight and ability to float due to non-interconnected porosity. Advanced analytical techniques such as SEM-EDS, XRD, and FTIR were used to confirm the material composition and characteristics.