Mechanical-microstructural characteristics of concrete containing high volumes of coal bottom ash

Abstract

This paper aims to study the effect of coal bottom ash (CBA) as a fine aggregate substitution at high levels on the mechanical properties and microstructure characteristics of concrete. CBA that sourced from a local coal-fired power plant in Vietnam was used to replace the natural sand (NS) in the concrete mixtures at different levels of 0, 30, 50, 70, and 100%. The concrete samples were prepared in the laboratory and checked for properties through the tests of compressive strength (CS), ultrasonic pulse velocity (UPV), water absorption (WA), porosity, electrical surface resistivity (ESR), and thermal conductivity (TC).