This research presents a study of the use of classified fly ash and ground rice husk ash as a pozzolanic material in producing high-strength concrete. Portland cement (CT) is partially replaced with classified fly ash and ground rice husk ash by weight of the cementitious materials. Compressive strength porosity and chloride penetration were investigated. The results show that the compressive strength resistance to chloride and low porosity of high-strength concrete improves substantially with partial replacement of Portland cement with fly ash and rice husk ash.

This research was to determine the appropriated mixing ratio of bottom ash and admixture (dust rock and Portland cement type 1) for improving the compressive strength. Bottom ash was used instead of soil and the quantities of admixture were 0 2 4 6 8 and 10% by dry weight of bottom ash. The specimens were cured for 7 14 28 and 90 days. Results of compressive strength test show that the admixture of 8% was the best mixing ratio. The increasing primary strength is developed from hydration reaction and the increasing secondary strength at 90 days is developed from pozzolanic reaction. Moreover the compressive strength of this specimen is close to the compressive strength of laterite