ẢNH HƯỞNG CỦA TRO TRẤU ĐẾN CƯỜNG ĐỘ, TÍNH CHỐNG THẤMCỦA BÊ TÔNG THỦY CÔNG

Abstract

This paper presents a method of rice husk ash (RHA) manufacture in the form of pilot and study on the influence of RHA to strength and waterproofing capability of hydraulic concrete structures. Results show that RHA was obtained by burning rice husk at the temperature of 600 - 800oC in 24 hours. The combustion of rice husk was designated to produce ash with the unburnt carbon content of 3,6%,  SiO2 content of 90,75%, active pozzolanic index of 290 mg CaO per 1g RHA and medium particle size of 17 μm. The compressive strength of concrete using 10% of RHA is remarkably higher than that of the reference concrete without using RHA at the ages of 28 and 90 days. It provides the possibility to increase the waterproof capability and decrease the penetration of chloride ion into the concrete. The samples and laboratory experiments were followed chemical – mechanical analysis methods and standards such as XRD, DTA, SEM, TCVN, and ASTM.