A Underwater Shield Tunnel External load Test Analysis

Abstract

Key word: Shield tunnel; Monitoring; water and soil pressure Abstract: A tunnel construction in a nuclear power plant is proposed in this paper. Some useful conclusions are drawn through the analysis of the measured results including the stress state and process of structure and water and soil pressure. It is useful for design, construction of similar engineering. Engineering survey Taishan nuclear power plant is the first EPR nuclear power plant in China; it is the world's largest single unit capacity of nuclear power. The maximum depth of the water intake tunnel is about 55.75m. The tunnel construction method uses shield method. The tunnel inner diameter is 7.3m, diameter is 8.7m, and the tunnel shield segments and two lining composite retaining structure. The shield segment thickness is 0.4m. Site monitoring and analysis of shield segment The theoretical problems of tunnel lining design is the model itself can reflect the actual situation of the project. For such complex factors, the simple use of a computing theory is difficult to truly reflect the actual engineering, therefore, this article through the method of field measurement, researching the shield tunnel segment stress process and state, and the soil pressure around the tunnel. Selection of monitoring section Monitoring section should be in the different overlying soil thickness and soil properties. Because the stability of IV, V and some kinds of third class III rocks is poor, and most of the type III and II class rock stability is generally good, therefore, the monitoring section is chosen in the IV and V rock stratum. Geological conditions of monitoring section