Packing density investigation of blended cement pastes incorporating waste perlite and recycled concrete powder

Abstract

Widely available industrial local waste materials could be viable solutions as supplementary cementitious materials. Aside from their possible positive effect on material properties, benefits are also expected in the environmental and economic sense. This is the case mainly because these materials do not have value in the market and are discarded as waste. This research examines locally abundant waste powders from the production of recycled concrete aggregate and perlite. For the investigation, the wet packing density method was used based on volumetric replacement ratios of cement ranging from 2.5 to 12.5% and 2.5 to 7.5% for waste perlite and recycled concrete powder, respectively. The ternary blended cements showed beneficial behaviour when compared to reference containing solely ordinary Portland cement. On the other hand, compressive strength is one of the key indicators of porous materials' mechanical and durability performance. Compressive strength measurements for the blended cement pastes were also obtained to identify the possible enhancement in the packing density and its effect on the mechanical properties of cementitious materials. It has been demonstrated that focusing just on packing density for investigation of the mechanical performance of cementitious materials when alternative solutions are concerned might not be the most robust approach.