The Lightweight Porous Fine Aggregate Composite Based on Secondary Raw Materials

Abstract

The main objective of this study was to carry out more detailed research on the effects of the amount of cement paste on the physical and mechanical properties of porous fine aggregate concrete (PFAC). Fine foamed glass aggregate (prepared of local glass breaks) and crushed expanded polystyrene aggregate (prepared of local packing tare of household equipment), ordinary Portland cement (OPC), plasticizing and air entraining admixtures, as well as pozzolanic additive – metakaolin-based waste (local waste in production process of foamed glass aggregate), were used for the preparation of forming mixtures. Fine aggregates were coated by an extremely thin layer of porous cement paste in the samples with the lowest amount of OPC (70 kg/m3), and the aggregates contact with each other mainly at the points (empty spaces between the aggregates are interconnected between each other). There were no empty spaces between the aggregates observed, and porous cement paste seems to be monolithic in the samples with the highest amount of OPC (370 kg/m3). Increased amount of OPC (from 70 to 370 kg/m3) results in denser structure, increased dry density, compressive strength, thermal conductivity coefficient and decreased water absorption of the samples.