Cerchar abrasivity index (CAI) and its relation to strength and abrasion test methods for marble stones

The Cerchar abrasivity index (CAI) is the most widely known test method for identification of rock abrasivity. The CAI value is related directly to cutter life in the field. On account of this, it is significant for building and constructions materials especially for the dimension stones. This paper presents strength tests, which are uniaxial compressive (UCS) and direct shear (DSS) influencing the CAI value. Additionally, the relationship between CAI and abrasion test methods that are Bohme abrasion (BA) and Wide-Wheel (WW) values are investigated. In the study tests were performed on 15 different marbles stone specimens. Results show that a strong correlation exists between CAI value, strength and abrasion test values. Based on this information, two converter charts were developed using multi regression analysis method.

► The CAI is the most widely known test method for identification of rock abrasivity. ► CAI value can be used for predicting of strength and abrasiveness of rocks. ► Uniaxial compressive (UCS) and direct shear (DSS) influencing the CAI value. ► Bohme (BA) and Wide-Wheel (WW) abrasion values of the rock are predictable with CAI.