Assessment of performance of lime mortars modified with natural additives for repair of historical structures

Abstract

The contemporary building material despite the significance of cement in the construction industry is the lime mortars because of its usage as a structural repair material around the ancient heritage structures. Though the significance of lime mortars lies in the fact of compatibility with the existing ancient lime-based structures, the method of construction and material preparations are still undisclosed. In such cases, it is necessary for the researchers to analyze scientifically, the influences of various additives on the performance of lime mortars. The literature commonly compares the efficiency of different additives in the preparation of lime mortar, but as far as the economy is concerned, it is necessary to adopt the optimum content to enhance the lime mortar properties without compromising the efficiency. This research work includes an attempt of incorporating two natural additives viz., gallnut (Terminalia chebula) and palm jaggery (Saccharam officinarum) as modifiers of mixing water in the preparation of hydraulic lime-based mortars through the process of fermentation. newlineThe research significance here lies in the fact that the studies made by the influence of those additives (palm jaggery and gallnut) towards durability properties were limited. The efficiency of the additives also largely influences the chemical composition of the additives; thus, it is also required to study the influence of hybrid additives i.e., the combination of a few best additives in a suitable proportion to test its efficiency towards the improvement of lime mortar. Thus, a combination of two additives was also analyzed to check its efficiency towards improvement in the properties of the mortar with respect to workability, strength, durability, microstructural and thermal parameters newline newline