Effects of rubber aggregate surface treatment on some properties of motar

Abstract

Rubber aggregates have very low elastic modulus, a reasonably smooth surface, and are highly water-repellent, so the air bubbles stuck to surface particles reduce the adhesive between aggregate and cement. The treatments on the surface of rubber particles can improve the adhesive and the mechanical properties of the mortar and concrete. The paper presents the treatment results on the surface of rubber particles and evaluates the modified particles on the mechanical properties of the mortar. The rubber aggregate immersed in NaOH solution for 30 minutes significantly improved the surface structure. The NaOH concentration of 20% enhances the highest in range of 20÷27% compressive strength, 11÷16% bending strength, and 21÷24% adhesive strength of the mortar.

Keywords: Rubber aggregate; surface of rubber particle; fineness modulus; NaOH solution; compressive strength; bending strength; adhesive strength.