CORRELATION BETWEEN UNCONFINED COMPRESSIVE STRENGTH AND INDIRECT TENSILE STRENGTH FOR JOINTED ROCKS

Abstract

Design Process in rock is very tedious because of its different nature compared to other engineering materials due to its distinct joint conditions like orientation, roughness, location & frequency affect the strength of jointed rock. Experimenting indirect tensile strength is very fast comparing with unconfined compressive strength. Material was created using plaster of Paris and water to simulate as jointed rocks. Three joint conditions were considered for evaluating the unconfined compressive strength using indirect tensile strength (joint orientation, joint roughness and number of joints). The model was prepared joint roughness using galvanized sheet, saw toothed blade and thin layer of bentonite clay in between the joints. By using multiple linear regression analysis unconfined compressive strength was predicted using indirect tensile strength. There is less number of research work carried out using jointed rocks for correlating unconfined compressive strength with indirect tensile strength. The present investigation was carried out to develop a relation between indirect tension and uniaxial compressive strength.