X-Ray and Microstructure of Rice Husk Ash-Admixed Concrete

Abstract Morphological changes which occured during the hydration of concrete containing rice husk ash (RHA) and Conplast SP 430 admixture (CP-admixture) were observed. X-ray analyses were used to identify phases, while the scanning electron microscope (SEM) analyses were used for the corresponding changes in microstructure with changes in the physical and mechanical properties. The effects of the admixtures and RHA on the concrete samples were investigated with and without Conplast SP 430. RHA was at 10 % replacement by wt. % of cement, and the dosage of admixture was 5.7 ml by wt. % of cement, and the water to cement ratio was 0.5. The results clearly showed the morphological changes that took place as hydration proceeded and showed the specific influences of each of the two admixtures. The additions of RHA and CP-admixture or both, modified the pore network and the composition of the main hydration product.