超大型土压平衡盾构穿越砂性地层施工技术研究

Research on the Key Techniques of Large Diameter EPB Shield Crossing Through Sandy Ground

用砂土液化的观点研究盾构穿越饱和砂质粉土引起的地表沉降机理进而用于解决实际工程问题。以迎宾三路超大型土压平衡盾构隧道为工程背景,在室内试验、现场试验和工程实践的基础上,提出并证明了超大型土压平衡盾构穿越砂性土层会引起砂土液化的观点,且针对性地采取了相应的工程措施,解决了超大型土压平衡盾构穿越砂性土层中遇到的开挖面失稳、注浆量失准、地表沉降失控的工程难题。

With a view to study liquefaction shield through the mechanism of surface subsidence caused by saturated sandy silt and solve practical engineering problems is a valuable attempt.In the background of a large diameter EPB shield tunnel,on the basis of laboratory tests,field tests and engineering practice,this paper proposed and demonstrated point of view that the large sandy soil pressure shield will cause soil liquefaction,and taken appropriate engineering measures to solve the super large earth pressure across the excavation face shield encountered sandy soil instability,grouting volume inaccurate,out of control surface subsidence engineering problems.