Construction Control Technology of Large Cross-section Rectangular Top Pipe Super Close Crossing the Existing Pipelines
In order to ensure the smooth implementation of large cross-section rectangular top pipes close crossing of existing sewage pipelines,combined with the risk source levels and the construction principle of large cross-section earth pressure balance rectangular top pipes,based on the rectangular top pipe project at the entrance and exit of Qingqiao Station on the Changnan Line of Beijing Metro,numerical models were established for calculation predic-tion.The key construction control measures were summarized and analyzed to innovatively obtain the key construc-tion technologies for large cross-section rectangular top pipes close crossing existing sewage pipelines;Gouting re-inforcement was carried out on the soil around the existing pipeline structure to improve the strength of the soil around the existing pipeline;Advance interception and diversion and implementation of UV in-situ curing technol-ogy to ensure the safety of the existing pipeline structure itself;The full earth pressure during the initiation and ex-cessive earth pressure excavation of the earth pressure balance pipe jacking machine ensure that there is no slight disturbance to the surrounding soil during the pipe jacking process;Finally,that mud replacement reduce the creep deformation of the existing pipeline structure in the later stage.The measured data shows that the key control tech-nology of ultra close crossing make the settlement of existing sewage pipelines is much smaller than the control value.This technology can provide reference and guidiance for the construction of same projects.
rectangular pipe jackingearth pressure balanceultra close crossingexisting structureconstruction control