Feasibility Study on Utilization of Compost as a Partial Replacement of Fine Aggregate in Conventional Concrete

Abstract. Solid waste management is the biggest challenge due to population growth. Lack of awareness about onsite processing of solid waste implies production of huge quantity of solid waste which is unmanageable. In this study an attempt is made to utilize the degraded solid waste called compost which is collected from municipal site and is used as a filler material in concrete. Compost is replaced for fine aggregate with 5%, 10%, 15% and 20% in conventional concrete. The compressive strength results at the age of 28 days are 30.5, 19.8, 16.8 and 18.2 N/mm2 respectively. Result indicates 5% replacement of compost is effective in concrete. The concrete specimen made with compost (CVC) and conventional concrete (CC) are exposed to an elevated temperature of 200°C, 400°C, 600°C and 800°C respectively. Result indicates the conventional concrete shows 5.3%, 6.1%, 15% and 24% compressive strength loss whereas 5% compost replaced specimen shows 10%, 11 %, 23.2% and 58.2% respectively. At an elevated temperature, both conventional concrete and compost-based concrete lost its strength. The reason could be thermal incompatibility between the aggregates and concrete. However, the loss of compressive strength is almost double in CVC than CC. The possible reason could be volatile compounds may evaporate in CVC at high temperature. The weight lost is observed in CC varies from 2.4 % to 4.5 % whereas CVC shows 6% to 7% from 200°C to 800°C. Weight lost is 3% more in CVC specimen than CC specimen.