Application Of Large Diameter Pipe Jacking Technology

Along with the development of the pipeline construction industry,the application of large-diameter pipe jacking construction is expanding gradually,and the construction conditions are more complicated.However,little systematic research of large-diameter pipe jacking construction is carried out in China.In this paper,the scheme comparison,equipment selection and modification for a canal crossing project of East China-Russia Natural Gas Pipeline are carried out.The project was successfully finished according to the selected pipe jacking scheme and its equipment.The construction process is also comprehensively analyzed,and the conclusions of this paper can provide a reference for the succedent project.The paper compares each construction schemes one by one in terms of geological adaptability,distance adaptability,comprehensive work efficiency and economy,and summarizes the constraints of each scheme.Furthermore,the applicability of various equipments is investigated,and the cutter header arrangement form of the selected slurry pressure balance pipe-jacking machine M1832 is redesigned after the characteristics of this project.In addition,the reasons for the deviation of the jacking force predictions are analyzed,and case studies verify that the China common empirical correlation for jacking force is the best one.For the entry and exit access control,the project adopts the fullsection cavity reinforcement technology which made the cavity treatment completely succeed with no water leakage during the construction period.On the other side,the slurry application reduces push resistance and protects the wall stability effectively,but whether less slurry circulation can play a better protective effect is worthing further studying.The measurement steering system is the core technology for curve and long-distance pipe jacking construction.The project adopts the gyroscope system,which has completed the survey and correction task well.However,the gyroscope system is imported from Germany,and its core technology is not mastered,so it can only be operated according to the tips of the operation console.