Underwater Maintenance Technology Based on The Barometric Cabinet in Second Channel Sluice of Gezhouba Project

Second Channel Sluice, with large amount of water discharge and long working duration, is the main water release structure on Gezhouba Project, located in Yangtze River of China. Concrete overflow surface in apron slab of Second Channel Sluice is subjected to repeated water erosion and impacted by high-speed flow and suspended sediment in water continuously, contributing to various degrees of abrasion. This article relied on the underwater maintenance technology of the barometric cabinet, combined with concrete overflow construction treatments on the defects of apron slabs and joints, introduced underwater overhaul technical measures, repair technology and material selection, and also construction efficiency of the slabs, to set a good example and help to similar working conditions.