Research On Freeze Design And Construction Technology Of Hangzhou Subway Connecting Passage

As China's population and urbanization rate continue to increase,the city's traffic congestion is becoming more and more serious,and rational use of urban space is the key to solving this problem.As a modern public transport,urban subway has the advantages of high speed,large passenger capacity and small environmental impact.As an important part of the subway tunnel line,the communication channel bears the functions of drainage,transportation and rescue..Due to the existence of groundwater,some of the communication channels have the risk of collapse and water seepage.The use of the freezing method has solved this problem well.The freezing method has the advantages of safety,cleanness and small impact on the surface.However,the research on the differential arrangement of the freezing tubes and the strength of various supporting forces in the freezing method needs to be strengthened.This paper firstly analyzes the formation of frozen wall and analyzes the formation process of frozen soil and the trend of temperature change in the corresponding stage.The mathematical model and temperature distribution law of temperature field in different stages are analyzed,and the conservative calculation formula of frozen wall thickness based on structural mechanics calculation is analyzed.Based on the construction of two communication channels between Zhejiang University Zijin Port Station and Sanba Village Station of Hangzhou Metro Line 5 Project,the two types of communication channels of different types are frozen and compared.When the communication channel structure is different,there is a significant difference in the freezing tube arrangement and freezing time.The finite element software ANSYS is used to numerically simulate the freezing strength index of the communication channel,and the displacement and stress of each position of the communication channel are obtained.The design of the freezing method is tested to meet the construction strength requirements,and the freezing design is optimized.Using the PKPM series STS steel structure software to calculate the general tunnel polygon support strength,calculate the support displacement of the project steel.The finite element analysis software SPA84 was used to calculate the strength of the steel bracket in the communication channel,and the rationality of the spacing of the brackets was verified.Finally,through the on-site monitoring of freezing temperature and pressure,combined with the relevant theory to analyze the freezing design.Figure[76]table[14]reference[46]...