ABSTRACT We report studies on brick-lime stepwell plasters used in the construction of twelfth century Gandhak-ki-baoli in south Delhi. The analytical examinations were performed using thin section, sieve analysis, XRD, XRF, FTIR, SEM-EDX and thermal analysis of the plasters. Studies indicate that elevated temperature fired coarse brick aggregate mainly improved the mechanical properties and permeability of the plaster. The coarse brick grains played the role of filler, as analytical examination evidenced the existence of partial hydraulicity in the plasters. Sieve analysis demonstrates the use of mainly medium to coarse size aggregate grains leading to better carbonation of lime. XRD and FTIR data indicate brick used was fired at a high temperature that destroyed the crystalline structure of the clays and loss of pozzolanic activity due to the reduced surface area and formation of high-temperature mineral phases. The Calcium silicate formed at the brick-lime junction reduced the porosity and improved the strength of the plaster beside making the plaster partial hydraulic.

中文翻译：

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新德里 Gandhak-ki-baoli 12 世纪砖-石灰阶梯井灰泥中砖骨料的矿物学和物理行为

摘要 我们报告了在德里南部 12 世纪 Gandhak-ki-baoli 建筑中使用的砖-石灰阶梯井灰泥的研究。使用薄片、筛分分析、XRD、XRF、FTIR、SEM-EDX和石膏的热分析进行分析检查。研究表明，高温烧制的粗砖骨料主要改善了石膏的力学性能和渗透性。粗砖颗粒起到填料的作用，因为分析检查证明灰泥中存在部分水硬性。筛分分析表明主要使用中等至粗粒度的骨料颗粒，导致石灰更好的碳化。XRD 和 FTIR 数据表明，使用的砖在高温下烧制，由于表面积减少和高温矿物相的形成，粘土的晶体结构被破坏，火山灰活性丧失。在砖-石灰交界处形成的硅酸钙减少了孔隙率并提高了石膏的强度，同时使石膏部分水化。