Research And Practice On The Construction Process For The Working Well Of New Tubular Roof Method

With the deepening of urbanization, metro construction is rapidly expanding, the surrounding environment has become increasingly complex, the problem are also more and more, the demand protecting the environment improve gradually, which propose higher requirements for the design and the construction technology of the metro project. In the process of metro construction, to learn and absorb from foreign experience, transform the foreign advanced technology and reliable experience to contribute to metro construction of the country. The new tubular roof method is a new metro construction method imported from abroad, the working well is an important part, the research and practice summary for construction process is the necessary prerequisite to promote the application of this methods.Based on the summary of the calculation method for deformation and design, then, a new metro station project of new tubular roof method as the example, the basic situation of methods of construction of the working well was introduced and the results of construction monitoring were analyzed, FLAC3D was used to simulate the whole process which includes excavation, applying internal bracing and pipe jacking, the results of simulation were comparative analysised with the construction monitoring data. The main contents and results achieved are as follows:The earth pressure distribution pattern for the working well of new tubular roof method was described, the methods of design and deformation calculation were summaried and discussed preliminary. Through the dissertation for construction method and the analysis of the construction monitoring data, the main features and key links of design and construction were studied, variation characteristics of the retaining structure, the surrounding soil and other objects by monitoring during construction process were summed up. Deformation of the retaining structure and the surrounding soil was small which occurred during construction process, the way and degree of the deformation effects for the retaining structure and surrounding soil from pipe jacking process were different, the stability problems of reaction wall occurred mainly during the first three top pipe jacking process and so on.