Effect of nano-CuO and fly ash on the properties of self-compacting mortar

Abstract

This paper presents the fresh and hardened properties of self-compacting mortar (SCM) incorporating nano-CuO (NC) and fly ash (FA). CuO nanoparticles at the rates of 1%, 2%, 3% and 4%, and low-calcium fly ash at the rates of 20%, 25%, and 30% of the binder by weight were considered. Mini slump flow diameter and mini V-funnel flow time tests were conducted to determine the rheological properties of SCMs incorporating fly ash and nano-CuO. Compressive strength was determined at the ages of 7 days as an early age, 28 days as the standard age and 90 days as a late age. Water absorption, electrical resistivity and rapid chloride permeability tests (RCPT) were also performed to determine the durability properties. The results showed significant improvement in the mechanical properties of the samples incorporating the replacement of cement with a combination of 3% CuO nanoparticles and 25% FA. Chloride permeability and electrical resistivity of the FA blended mixtures improved with the increase of nano-CuO content up to 4%. The SEM micrographs indicated more packed pore structure of the SCMs containing nanoparticles which could lead to increasing the strength and durability of specimens.