Influence of recycled clay brick aggregate on the mechanical properties of concrete

Abstract

Abstract This article presents the experimental results of the compressive strength, the splitting tensile strength, the macro destruction mode, and the microstructure of recycled clay brick aggregate concrete (RBC) with different recycled clay brick aggregate (RBA) replacement rates. The results show that the compressive strength and the splitting tensile strength of RBC are lower than those of natural aggregate concrete (NAC), but the effect of RBA on the splitting tensile strength of concrete is not significant. The effect of the water–cement ratio (w/c) on the splitting tensile strength of RBC is smaller than that on the splitting tensile strength of NAC. The compressive strength of concrete shows a trend of first decreasing and then increasing with the increase in RBA replacement rates. The effect of RBA replacement rates on the compressive strength gradually decreases with the increase in the w/c. The AFt in NAC is thicker than that in RBC, and the C–S–H of RBC is in the form of agglomerated networks with large and uniform pores and less filler.