ABSTRACT: CERCHAR Abrasiveness Index (CAI) plays an important role in determination of rock abrasivity. Themain factors affecting the abrasiveness of rocks are amount of hard minerals such as quartz, rock density, degree of cementation and strength characteristics. In this study, rock samples of Austin (Texas - USA) weretested, weak limestone samples were tested according to CERCHAR method and relationships betweenabrasiveness and the strength properties of the soft rocks were investigated. Considering abrasion of therock and steel together, wear on the steel and indentation on the rock that occur at the same time weremeasured and tried to be correlated. Potential usage of CERCHAR method, which is currently used forestimation of life of excavation tools, was investigated for prediction of strength properties of weak rocks.As a result of the study, CAI values of the limestone samples were found less than 1.72, while the majorityof the results was found in the range of 0.2 to 1. In this study a good relationship has been found amongCAI and UCS and TS values, by the statistical analysis of the test results. Another good relationship wasobserved between CAI and indentation depth (ID). Similarly, ID has good correlation with the UCS andTS. . CAI parameter used in the determination of rock abrasivity and CERCHAR method used to obtainit have been suggested be improved for the soft rocks. It is concluded that, in addition to CAI values, bymeans of indentation depth measurements in CERCHAR tests, prediction of other rock properties will bepossible.