SHALE DISINTEGRATION AS A FUNCTION OF PHYSICAL AND THERMAL BEHAVIOR

Increasing use of rock materials like shale in building, roofing, embankment filling, brick manufacturing, and in other civil structure application makes it an important rock to consider in construction engineering. The thermal and physical behaviors of shale are important characteristics which should be estimated before using them as construction and building materials. Shale which make up about 75% of most sedimentary rocks are complex and show considerable variation in terms of their physical and thermal properties. These properties are directly linked to their durability and strength. The purpose of this research was to study the physical and thermal behavior and compare them with the durability and strength parameters of shale rock mass. Thirty-six fresh rock samples were collected from Sevier Shale, a complexly folded, thrust faulted and diverse rock-mass sequence in southern Appalachian Valley and Ridge Province. Shale samples were subjected to series of laboratory tests, which included multi-cycle Slake Durability Index (Id), Unconfined compressive strength (UCS), Specific heat capacity, bulk density, natural water content, and porosity. The tests were performed according to the standard ASTM (American Society for Testing and Materials) methods. Results indicated that properties like porosity, durability, strength and specific heat capacity varied significantly within samples, where as density and water content yielded steady values. Regression analysis was performed to evaluate possible correlations among the tested properties. Strong inverse relationship was evident between specific heat capacity, durability and porosity. Specific heat capacity increased UCS of shale. This study emphasized that physical and thermal properties of shale are directly linked with strength and durability of the rock mass.