Comparison of Morphological Properties of Different Types of Coarse Aggregates

Abstract

The present study was undertaken to compare angularity, texture, and flat and elongated (F&E) particles of three different types (namely, granite, rhyolite, and limestone) of coarse aggregates. An aggregate imaging system (AIMS) manufactured by Pine Instruments Inc., was used to measure the shape parameters of the aggregates. Comparison of shape parameters was performed by plotting the distribution of different types of angular particles (i.e., rounded, sub-rounded, subangular, and angular), texture particles (i.e., polished, smooth, low, medium, and high roughness) and F&E particles (maximum to minimum dimension ratio = 5:1 and 3:1). In addition, analysis of variance (ANOVA) was conducted to compare the mean of the shape parameters. Results show that no significant difference exists in angularity of different types of aggregates. However, texture was found to be significantly different for the three types of aggregates considered in this study. It was observed that the granite aggregates have the highest texture followed by the limestone and the rhyolite aggregates. The study indicates that aggregates can have same angularity but can differ significantly in texture. The distribution of F&E particles shows that three aggregates had less than 10% and 20% of particles with maximum to minimum dimension ratios 5:1 and 3:1, respectively. It is expected that present study will be helpful in understanding the shape parameters for different types of aggregates.