Abstract:Taking the construction of Dangui Road Station in the Shanghai Metro Line 13 East Extension Project as the background, aiming at the problems such as narrow site, high soft soil water level and severe requirements of environmental protection faced in the relocation and reconstruction of rainwater and sewage pipelines within the protection areas of rail transit, the application practice of slurry-balanced micro pipe-jacking technology in the trenchless construction of DN1200 large-diameter rainwater and sewage pipelines is introduced. By comparing and selecting the technical routes of the conventional excavated trenching and micro pipe jacking, the micro pipe-jacking method is finally selected for construction. In the engineering implementation process, the risks of the whole construction process can be controlled through the measures such as dynamic regulation of jacking parameters, frequent measurement and correction of attitude, minor adjustments, and real-time monitoring and feedback control of ground settlement. The measured results show that the ground and surrounding structure settlements during the construction period all meet the control requirements for the protection area of rail transit. The engineering practice demonstrates that the slurry-balanced micro pipe-jacking technology can significantly reduce the construction risks and environmental disturbance under the condition of close proximity to rail transit, and the smooth connection with the construction of main structures has been achieved.
