Construction Technique Study On Metro Station And Running Tunnelling By Excavation In Watery Strata

In the careful analysis of the construction environment and hydro-geological conditions of Science Building Station of Shenzhen Subway, this thesis makes a comparison between the methods of "cover-excavation consequent operation", "cover-excavation obsequent operation" and "hidden excavation" applied in the excavation of subway station construction and generalizes the respective characteristics thereof. Then it illustrates the key technique of "cover-excavation consequent operation" applied in the construction of the aforesaid subway station in Shenzhen. Meanwhile, it examines and discusses the function and design of the temporary surface system by calculating.Through the applocation fo the "metro-technique", the changes of mechanical parameters for the footing groove and the strain of the stress on the supporting structures are measured during the whole process of the construction. And the data obtained thereform are analyzed for the guidance of the modification and perfection of the various techniques so that the method of "cover-excavation consequent operation" can be implemented successfully.As far as complicated geologic condition with weak watery strata, complex construction condition with multi-tunnel system and complex environmental condition with adjacent to building and pipeline are concerned, difficulty and risk of construction are very great and the mechanism of ground settlement and its distribution are also very complex. It is revealed by domestic and overseas data and literatures that research on it is poor, so theoretical study is very weak compared to flourish metro engineering. Relative study in this dissertation is carried out combined with Shen-zhen metro engineering and multi-research techniques are used, on the one hand, so as that results acquired are reliable and reasonable, on the other hand, they can be verified each other and learn from other's strong point offset one's weak point. Because results acquired in the dissertation by means of numerical simulation and test are basically consistent with the results by spot measuring, analysis theory and method concerned in the dissertation is reasonable, and prediction before construction is almost right is also proved. Thus theoretical basis and guidance are provided to real engineering, at the same time, a series of key techniques and problems are solved. Valuable design, construction and scientific research experience is accumulated and provided to similar engineering. Outstanding construction achievement by real engineering indicated that it is a necessary direction to increase scientific research expense of great and complicated engineering.