Proceedings of ISERME 2021 ISERME 2021 26 Correlations between Durability, Mineralogy and Strength Properties of Limestone Senarathna TMB, Janith SHMPK, * Dassanayake ABN, Chaminda SP and Jayawardena CL Department of Earth Resources Engineering, University of Moratuwa, Sri Lanka *Corresponding author – anjula@uom.lk Abstract Durability is used to depict the obstruction of rock to weathering and the pace of events of such changes. Wetting and drying cycles cause evaluation of physical changes and slaking behaviour of rocks, and that can be appraised by the slake durability test. Correlations between durability, mineralogy, and other physical-mechanical properties are different with the rock. Physical and mechanical characteristics of High-grade limestone samples and Low- grade limestone samples from the Aruwakkalu mine were determined according to ASTM standard methods. X-ray diffractometer (XRD) analysis and scanning electron microscope (SEM) analysis were used to determine the mineralogical contents of the studied samples. Regression analyses were performed between the slake durability index and the physical- mechanical properties of limestones to identify the best wetting and drying cycle to assess the relationships. Differences between the physical, mechanical properties, and mineralogical contents of High-grade limestone and Low-grade limestone were also identified from the laboratory test results. Finally, this study will help to understand any rock engineering problem relating to durability, mineralogy, and other physical-mechanical properties of areas with limestone. Keywords: Limestone, Regression analysis, SEM analysis, Slake durability, XRD analysis 1. Introduction Physical properties, strength, and durability are essential properties that help to assess the rocks for various applications. Determining the suitability of rocks for use under various environmental and stress conditions is mostly rely on these physical properties. The durability and strength of rocks generally help to categorize different types of rocks. The ability of a material to resist deformation induced by an external force is known as Strength [1]. Durability is an indicator of the ability of rocks to withstand and sustain their distinctive strength and resistance characteristics. Rocks are subjected to alternate dry and wet conditions and undergo repeated water absorption and dehydration steps. This cycle is called the Wetting and Drying cycle of rocks [2]. Many physical and mechanical properties of the rocks are changing with these cycles. The load of past durability characterizations depends on the subsequent cycles' durability index [1]. The most immediate control on