Effect of mixture composition on washout resistance of highly flowable underwater concrete

摘要

The underwater casting of relatively thin lifts of concrete in water requires the proportioning of highly flowable concrete that can resist water dilution and segregation and spread readily into place. An investigation was carried out to determine the effects of anti- Washout admixture concentration, water-cementitious materials Ratio, and binder composition on the washout resistance of highly Flowable concrete. Two main types of antiwashout admixtures were used:1)a pow- Dered welan gum at concentrations of 0.07 and 0.15/100(by mass of Binder); and 2)a liquid-based cellulosic admixture with dosages Up to 1.65 L/100 kg of binder. The water-cementitious materials Ratios were set at 0.41 and 0.47, corresponding to high-quality Underwater concrete.