Study on Specific Compressive Strength of Concrete with Fly Ash Cenosphere

Abstract

The properties of concrete, such as compressive strength and density, are the key properties that control the size and self-weight of any structure. Hence, concrete with high strength-to-density ratio (specific strength) can reduce the vulnerability of a structure against earthquake and also can reduce the operational energy consumption. Therefore, this investigation is focused on the study of the variations in specific compressive strength (SCS) of concrete incorporating fly ash cenosphere (FAC) as an alternative of natural fine aggregate (NFA). By doing so, the pollution of soil, water and air due to disposal of FAC can also be solved. To fulfil the above objectives, concrete mixes are prepared by replacing various fractions of NFA with FAC. The compressive strength and oven dried density of these concrete mixes are evaluated. Thereafter, the SCS of all these concrete mixes are calculated. The outcomes of the above study reveal that both density and compressive strength of FAC-based concrete are less than those of normal concrete. The decrease in density is due to the lightweight nature of the FAC and reduction in strength is due to the inferior bonding between FAC and cement paste. It is also found that the rate of reduction in compressive strength is higher than that of density. As a consequence, the SCS also gradually decreases with increase in the replacement of NFA with FAC. Therefore, it needs further investigation to enhance the SCS of concrete by increasing the compressive strength with minimum variation of density.