A comparison study between basalt and granite crushed rocks under repeated traffic loads

Class 2 crushed rock is used as an unbound granular pavement base material in Australia. Commonly, there are several types of Class 2 rocks attributed to their origins. Roads Corporation of Victoria (VicRoads) specification assigns several requirements including Los Angeles Value to characterise the strength of the base layer’s crushed rock. As the base materials are exposed to traffic loads, it is more rational if it is characterised under similar loading configurations. Two types of Class 2 rocks are used in this study- crushed basalt and granite rocks. A repeated load triaxial test (RLTT) was conducted to assess the permeant deformation (PD) properties for both types of crushed rocks. The results from the RLTT test shows that Class 2 crushed basalt rock has PD varied from 2.0% to 4.3 % while PD of Class 2 crushed granite rock varied from 1.0% to 2.3% meaning that granite rocks are comparatively superior to their basalt counterparts.