Study on the use of antiwash high performance concrete for rehabilitating the hydraulic structure submerged in water

Tóm tắt

Antiwash high performance concrete (AHPC) is a specialized type of concrete used for construction projects where concrete needs to be placed below the waterline. With the aim to extend the service life of the hydraulic structures under water, this paper attempts to study on AHPC and its usage for rehabilitating the structure submerged in water. To do so, four AHPC mixtures have been involved in the experiment, in which superplasticizer dosages varied from 1% to 2% in conjunction with a specialized anti-washout admixture. Besides, a particular AHPC mixture would be used for repairing the structure by underwater concreting. The experimental results have shown that at fresh state the higher superplasticizer dosage, the higher slump flow of the AHPC mixtures, and the higher mixture mass loss inside the water. Meanwhile, at hardened state the higher superplasticizer dosage, the higher compressive strength gains. The single AHPC, which achieved slump flow of 20 cm and strength class of 50MPa, was chosen for successfully rehabilitating the structure submerged in water by mean of tremie method. The proposed future work could involve the study on mechanical performance of the concerned structure after rehabilitation. Keywords: Antiwash high performance concrete, hydraulic structure, underwater concreting, anti-washout admixture, superplasticizer