Interdependence between point load index, compressive strength and crushing resistance of Jordan oil shale and relation to calorific value

Abstract

Rock parameters are important to be considered in mine design. Physical-mechanical tests were carried out on oil shale and dolostone samples from the Attarat Um Ghudran oil shale area in central Jordan, in order to determine the rock mass properties. It was necessary for assessing the feasibility of excavation and processing. Half-core and core samples were compressed up to failure during the Point Load Test (PLT) and Uniaxial Compressive Strength Test (UCST), respectively, and the PLT index (PLTI) and compressive strength were calculated. A conversion factor between PLTI and UCS for Jordan oil shale and dolostone was determined. The Crushing Resistance Test (CRT) on samples was conducted. Taking into consideration confidence limits, the recommended conversion factor 1 for Attarat oil shale and dolostone is respectively 14 and 12 and the recommended conversion factor 2 is 33 and 12, respectively. This knowledge is relevant in designing selective excavation and dry separation of oil shale.