Research and application of sinking-aided methods for circular open caisson under complex formation conditions: case study

Open caissons have been widely used owing to their good structural integrity and waterproofing performance, convenient construction, and low cost. However, sinking construction is affected by many factors, such as geological conditions, groundwater, designed depth, and self-weight. Improper measures may lead to severe subsidence of the surface and adjacent structures of an open caisson and even adversely affect its structure. This study using a large-diameter circular open caisson in the Jinshan Lake, Zhenjiang, first examines the causes of its substantial sinking and stagnation during construction. Owing to the different leading causes, sinking-aided methods differ. Therefore, these methods and their subsequent optimization schemes are established, and their effects are analyzed to provide a reliable reference for future related projects.