Numerical Simulation Study On The Effect Of Double-Wire Shield Tunneling On The Ground And The Existing Building Settlement

In recent years,China has developed a wave of infrastructure construction.Big cities rushed to build the subway.Lanzhou city is also actively preparing for the construction of lanzhou subway line 1 and line 2.Since lanzhou city had no previous experience in subway construction,the construction of lanzhou metro line 1 is based on reference and experience of subway construction in other areas.Subway construction inevitably affects the surrounding buildings,structures and underground pipelines and other urban facilities.The facility deformation affects normal use and even destroys the facilities.so it is necessary to study on the influence of the construction process on the surrounding buildings in lanzhou subway shield construction.Through in-depth study,The research work is as follows:(1)Soil conditions affecting factors of shield construction settlement,soil parameters,single shield forward distance,excavation face supporting force,the upper structure stiffness,double spacing,double shield advance about line excavation face of shield tunnel axis of two spacing these seven factors for numerical simulation are researched.We assign four or five different levels of parameters to each factor and the value of the parameter is changed by arithmetic.Then the settlement law of soil under different variables is analyzed.(2)The settlement law of soil,the settlement law of building,internal force distribution of buildings and internal force distribution of lining are analyzed.In the process of construction,The change rule of the above research object is analyzed.It is compared with the variation law of soil of the natural surface.(3)The settlement measures can be effectively controlled in shield construction.Three aspects of shield tunneling parameters,tail grouting and building reinforcement are analyzed.The concrete measures of these three kinds of control subsidence are studied.