Comparison of drillability and abrasivity properties of rocks

Abstract

Drillability is defined as the penetration rate of a drill bit into the rock. Abrasion is broken off by the tools during the excavation of rocks. Different types of rock formations have different abrasiveness and hardness properties and that is significantly affected excavatability and drillability in the mechanical excavation systems. Because, abrasive rocks and hard rocks lead to an increase of the cost excavation, decrease of the penetration rate and atrophy of the cutter in a short time. This study was carried out in Hopa-Borcka (Artvin) Cankurtaran Highway Tunnel. Rock samples were obtained from Cankurtaran Tunnel at the changing rock formations for the laboratory studies. The test samples were prepared at the appropriate size and quantity. Sievers J-miniature drill test (SJ) and the brittleness tests were carried out and for the drilling rate index values were calculated. Cerchar Abrasivity Index (CAI), Norway Abrasion Value (AV) and Bohme abrasion tests were carried out and for abrasiveness of rock properties. Uniaxial compressive strength, point load strength and Brazilian tensile strength tests were determined for the calculations mechanical properties of rock.