INVESTIGATION OF THE CHEMICAL ADMIXTURE INFLUENCE ON THE PERFORMANCE OF SELF COMPACTING CONCRETE

A new formulation approach by using fines material supported by development of chemical admixture open the way to amazing progresses in concrete technology. The range of perfomances and characteristics that are covered by concrete have been expended in two way directions from conventional concrete to self compacting concrete (SCC). In order to establish an admixture system which can fulfil the SCC requirements, the mixes contained either a small quantity of fly ash (20%) or none. The aim of the research is to evaluate and invertigate the use of chemical admixture in SCC mixes that influent the properties of hardening concrete. Three different chemical admixture were used in the research. Decreasing the water-cement powder ratio may negatively influence the flowing ability of fresh concrete. Special attention must be paid to add of mineral admixtures, like fly ash are often used to modify the microstructure of the concrete matrix and to optimise the transition zone. The reduction of water-cement powder ratio in a decrease in porosity and increase the performance hardening concrete. In this research water to cement ratio around 0.28. The results shown that the lowest value of water-cement ratio the higher use of chemical admixture and increase the compressive strength of SCC (MixCA3).