Study On Support Structure Of Excavations—in Haining Region

With the stong growth of the regional economy, rapid urbanization and development and utilization of underground space in Haining, a large number of excavations engineering infranstructures have emerged. However, causes such as improper investigation and design, poor project management and construction etc occaionally lead to accidents in excavations engineering, which brings big economic loss to the society and great pressure to the safety of the region.This paper collected and analyzed36real cases of excavation engineering projects in Haining region since2009and summarized different forms of support structures, dewatering and drainage systems, and historical accidents with handling methods that happened in Haining, followed by recommendations of how to choose from different drainage and dewatering structures based on different environmental conditions, geological conditions, hydrological conditions and excavation depths.This paper analyzed the typical features of both successful and failed excavation engineering projects in Haining region, by studying the data from two projects:the ex-situ relocation of Haining building decoration materials market and excavation engineering process of Haining Intime Town. It provided a reference for future excavation pit design and construction in this region.Ignoring pit in pit in the realworld construction would impact negatively on the stability and transformation of excavation support structures, which would cause security risks. This paper specifically targeted on the excavations under the typical deep soft soil conditions in Haining. It analysed the impact from the size, location and depth of the "pit in pit" structure to the to deformation and internal forces of the excavation support structures, by utilising the massive three-dimensional general finite element software ABAQUS.