An investigation of the relationship between Los Angeles abrasion loss and rock texture for carbonate aggregates

Abstract

Rock aggregates are the most fundamental material of highway, railroad, and other construction activities. The quality of rock aggregates for a given usage is determined by many different test methods, one of the most important of which is the Los Angeles abrasion (LAA) test as it is used to evaluate the resistance to abrasion and wear of aggregates for such applications as railroad ballast, base course material, and asphalt and concrete aggregates. In this study, the relationship between rock texture and LAA loss was investigated for 26 sources of carbonate aggregates found in Iran which constitute the most commonly quarried crushed rock. Regression analyses were used to determine whether rock texture was a useful predictor of LAA loss. The texture of rock aggregate was quantified by texture coefficient (TC), which can be used to put a value on rock texture with studies carried out on the rock thin section using image analysis. In addition, the effects of textural parameters including area weighting of grains or packing density, grain shape, grain elongation, circularity, and orientation of mineral grains, and also TC on the LAA loss were evaluated. Although the results show that weak relationships exist between textural parameters and LAA loss, a strong relationship exists between TC and LAA loss. The results indicate that many textural parameters, together with TC, can be interpreted as rock texture which influences the LAA loss. Also, the results indicate a strong negative correlation between LAA loss and TC, and can be used to predict LAA loss in practical applications.