Structural behavior of self-curing concrete with partial replacement of coarse aggregates with fly ash pellets

Abstract

As we are in the world to conserve water for our daily needs, the present technologies have to be optimized in a feasible way, especially to one of the process curing in construction field. Thus, indeed there is an immediate need to do research on water used for curing process on concrete. Curing is one of the significant process for the concrete to have sufficient moisture content particularly at early stages of concreting in order to enhance the property of the concrete. It also plays a major role in concrete by developing pore structure and microstructure thus enhances its performance and durability. By considering these importance’s about curing and also to minimize the water for curing of concrete, a study has been conducted on concrete with the help of Polyethylene Glycol-400 (PEG-400) a water soluble self-curing agent to reduce the usage of water for curing. The present study also emphasis the use of fly ash pellets (FAP) prepared from the waste fly ash as coarse aggregate partially. The trail mix of concrete is proportioned replacing coarse aggregate by 10%, 15%, 20%, 25% and 30% with FAP and the compressive strength of the concrete were determined and found the optimum percentage replacement of coarse aggregate with FAP is at 25% resulting maximum compressive strength. The mechanical properties of concrete using water-soluble Polyethylene Glycol (PEG 400) have been found and also identified the optimum dosage to achieve maximum mechanical properties of the concrete. The increase in water retention capacity in the concrete and reducing the water evaporation in curing process can be done by using self-curing agent and it will absorb the water from the atmosphere thus saves water in the curing process compare to conventional concrete. The concrete mechanical properties containing self-curing agent are studied at various percentage such as 0.5, 0.7, 0.75, 0.8 and 1.0 added by weight of cement and compared with those of conventionally cured concrete. From the investigation it has been concluded that optimum dosage of PEG-400 for maximum mechanical property of M25 grade of concrete containing 25% of fly ash pellets as coarse aggregate is at the percentage of 0.75 by weight of cement.