A Study on Mechanical and Durability Properties of Structural Concrete using Pumice and Sintered fly ash Aggregates

Abstract

Lightweight aggregates has low density, high permeability than the conventional coarse aggregate. Most commonly available lightweight aggregate (LWA) are Pumice aggregate (PA), which is a natural aggregate, sintered fly ash aggregate (SFA), which is made by sintered processing the fly ash obtained as a by-product of coal based Thermal power plants. Among the many artificial aggregates, SFA is used as a replacement to coarse aggregate to produce lightweight aggregate concrete. This paper presents an experimental study of structural lightweight aggregate concrete (SLWAC) using combination of PA and SFA as a partial replacement for coarse aggregates. In this, the mechanical and durability properties of SLWAC using different percentages i.e., 25%, 50%, 75% and 100% of PA and the rest natural coarse aggregate, fully replacement of coarse aggregate with 50% PA and 50% SFA, are evaluated by conducting comprehensive series of tests on strength and permeability parameters. The test results showed better strength and adequate density, at coarse aggregate replacement with 50% PA and 50% SFA, to be accepted as SLWAC as per ASTM standards. When the coarse aggregate is completely replaced by pumice aggregate alone, the strength achieved is poor and is suitable for non-structural members. In this study, the mixes are designed for M25 grade concrete and the results are then compared with M25 grade of conventional concrete (CC).