Relationship Between Rock Abrasivity and Tensile Strength

We discussed the relationship between rock abrasivity and tensile strength so as to provide clues for the choice of cutting head of tunnel boring machine. A total of 24 samples belonging to four lithologies were tested for abrasivity and uniaxial tensile strength. Correlation analysis indicated that rock abrasivity is not a mathematical function of tensile strength; rather, the two have a positive correlation in a qualitative sense. Two influence factors of rock abrasivity are contents of hard minerals (typically the quartz) and the mode and strength of mineral bonding (crystallization and cementation). We found that rock abrasivity is the result of combined action of several factors. In tunnel construction, the choice of cutting head of TBM should be based on consideration of the effect of several factors on rock abrasivity.