EFFECT OF DEGREE OF SATURATION ON PARTICLE BREAKAGE OF RECYCLED CONCRETE AGGREGATE UNDER CYCLIC LOADING

Abstract

Construction of road infrastructure consumes a large volume of natural crushed rock, which is used in different layers of the road pavement structure. The use of construction and demolition waste (CDW) for manufacturing recycled concrete aggregates (RCA) that are suitable for engineering aspects of road construction contributes not only to decreasing the exhaustion of natural resources but also to the promotion of CDW recycling. The performance of recycled concrete aggregate (RCA) as a granular roadbed material depends on various field loading conditions (e.g., traffic load) and environmental factors (e.g., degree of saturation, S_r). Particle breakage is one of the important aspects that affect the performance of RCA, especially for evaluating the long-term pavement performance under field traffic conditions. However, the effect of variable saturation of RCA on particle breakage under cyclic loading is not fully understood. Therefore, this research performed both static and cyclic triaxial tests to study the strength and deformation behavior of RCA with variable S_r and examined the particle breakage of RCA based on Marsal’s breakage ratio and mass reduction/accumulation of coarse aggregate using a coloring technique. The results showed that S_r affected the deformation of RCA and that the permanent axial strain increased with increasing Sr. On the other hand, S_r contributed to reducing the particle breakage of RCA under cyclic loading and the breakage of coarse fraction decreased with increasing S_r of RCA.