Study On Optimization Of Lining Structure For Shield1Tunnel Segment In Oil And Gas Pipeline

The rapid economic and social developments of China have resulted in increasing demand for energy resources. As the west to east gas pipeline project, the engineering of gas pipeline provide a foundation of energy delivery. It is necessary to build the tunnel through the mountains and rivers in pipeline projects. At present, the design and construction of tunnel is being developed quickly, especially in shield method. Shield method becomes one of the main methods in oil and gas pipeline crossing project. There exists some difference between tunnel of oil and gas pipeline and subway tunnel or highway tunnel, such as the difference of load condition and the cross section. This paper base on the case of Xijiang shield tunnel in Guangdong gas pipeline. The main research method of this paper is numerical simulation. Following aspects are the main studies in this paper.1. Determined a reasonable thickness of tunnel segment by simulating the internal force and deformation of four kinds of segment thickness with considering the geological conditions of Xijiang shield tunnel on typical cross sections, by means of elastic uniform rigidity ring model of load-structure model.2. Chosen a reasonable division of shield segments by simulating the internal force and deformation of different segment block number and different assembly Angle of shield segment with considering the geological conditions of Xijiang shield tunnel on typical cross sections, by means of Beam-spring model of load-structure model.3. Chosen a optimized Width of shield segments by simulating the stress and deformation on the longitudinal direction of3kind of width with considering the geological conditions of Xijiang shield tunnel on typical cross sections, by means of shell-spring model of load-structure model.The main conclusions of this study are as follow:1. The cross section of shield method tunnel in oil and gas pipeline is smaller, we should firstly simulate the internal force and deformation of different thickness of shield segment, and then choose a better thickness by design checking computations according limit states.2. After simulating the internal force and deformation of different segment block number and different assembly Angle of shield segment, we consider that we should reduce the number of segments as far as possible. There exists some benefit for staggered joint when we use irregular assembly Angle of shield segment. 3. In the longitudinal direction of shield tunnel, it is necessary to improve the hole rigidity by using wider shield segments. In the case of this paper, if the condition of transportation, assembly process and construction are permissible, we should choose1.5m as the Width of shield segments first.