The Research On The Key Point Technique Of The Pipe-roofed Wide Box-culvert Jacking

With the rapid development of the economy and the population, the city traffic is becoming more and more crowded. In order to loosen the traffic jam, many cloverleaf junctions and subways are constructed. An underpass, a section of road that passes under another road is typical.The tunnel of Shanghai Middle Ring Line is carried out by the pipe roof culvert box advancing scheme. By this method, the influence to the traffic on the ground was lessened to the least in the construction process. And the ground settlement is also well controlled.In this thesis, by means numerical analysis and theoretical research, the underpass of Beihong road is researched and some key points of the pipe roof design method are proposed. By analyzing the factors to the ground deformation and the mechanics action of the pipe roof, some theories are concluded. Based on the conclusion, some measures are recommended to control the ground settlement; The material of injecting slurry and its property are studied. The reciprocal-action mechanism of soil and mud slurry around the culvert box in the course of injecting slurry is investigated, and several problems which should be paid attention to in injecting slurry is put forward; The pose of the jacking culvert box in different load case is studied with the model of beam on elastic foundation in order to explain the up-and-down phenomena of the ground surface. And also some measures are proposed to control the pose of the jacking culvert box according to the explanation.