The Study Of Influence And Construction Control When One Shield Tunnel Of The Subway Line Crossing The Guangzhou-Shenzhen Railway Brige

In an urban environment, a lot of high-rise buildings and bridges are supposed by pile foundations. When shield tunneling adjacent to pile foundations is unavoidable due to underground space restrictions, though great progress has been made in shield technology at present, it almost inevitably causes ground movements which in turn will impose additional axial and lateral forces on, and lead to additional displacements of,adjacent pile foundations. This has become an issue urgently needed to be resolved to assess the likely impact of shield tunneling on adjacent pile foundations and take protection measures. Using site monitoring data, numerical and theoretical analysis, this dissertation conducted a systematic research in the following aspects:1. The features, mechanisms and factors of ground movements caused by shield tunneling are summarized. On the basis of monitoring data of Guangzhou metro No.2line project, the characteristics of ground movements caused by combined shield driving in mixed soft-and-rigid strata are investigated, and a method is proposed for estimating ground movements induced by shield tunneling.2. The features and mechanisms of the pile responses are discussed. Summarized the relationship of the pile and the location of the shield tunnel based based on the features of shield construction. At last,the shield stage of the construction impact on the pile has been divided.3. A method for analyzing responses of the bridge caused by shielding tunneling is put forward. Using the Ansys software to simulate the Guangzhou metro No.2line beneath the Guangzhou-Shenzhen railway bridge, the analysis of the bridge deformation caused by shield construction on the basis of reasonable modeling and parameter selection is put forward.5.Analyze the deformation law of Guangzhou-Shenzhen railway bridge in different parameters of shield and construction scheme to provide reasonable recommendations and guide the similar construction.4. Procedures and control methods for shield tunneling adjacent to pile foundations are presented. Control of construction parameters、auxiliary treatment measures for pile foundations and methods for assessing pile responses caused by shield tunneling are emphasized.