Research On Safety Prediction And Control Of Mountain Tunnel Construction Based On The Inversion Theory

Along with the construction of tunnel engineering,the safety problems has got more and more attention in the process of tunnel construction,the safety accident of tunnel construction always occurred because of the complexity geological conditions and some other factors,and it had brought huge casualties and economic losses to the society.In order to reduce this kind of safety accidents,the first important thing is finding out the detail condition of the geological condition before the excavation of the tunnel(especially for the distribution of bad geological bodies),the second important thing is the monitoring measurement of the tunnel state in the process of tunnel excavation,and at same time,making a good use of monitoring data timely and effectively,and then it will help us to provide some valuable advices for the tunnel construction.In this paper,our research is based on xin-long tunnel belonged to dongtou county of wenzhou,and using the more effective means to detect the state of the changing of tunnel lock,and then with the help of relevant theories and finite element software,we can do useful analysis to provide some powerful reference data for the next step of construction.The main results were as follows:(1)Before the tunnel excavation,we can have a detection of the surrounding rock through the advanced geological prediction technology in the early,and have a known about the distribution of the bad geological body so that we can take some measures in advance.And got a correction data about the level of the tunnel surronding rock on the basis of survey data,which can help us to provide a reference for the selection range of surrounding rock parameters.(2)Take the field monitoring measurement data as a basis,to study the law of the surrounding rock deformation under different buried depth 、different excavation methods 、excavition method and so on,at the same time,combined with the regression analysis method and the space effect analysis method to get the total deformation value of surrounding rock,and to prepare for back analysis of the surrounding rock displacement.(3)according to the deformation characteristics of surrounding rock,elastic model had been established,and then take the measured displacement as a basis,with the help of the golden section method and the finite element software ABAQUS,we completed the inversion analysis of tunnel surrounding rock parameters,the inversion results are the equivalent elastic modulus and the coefficient of lateral pressure of surrounding rock.(4)on the basis of the above inversion parameters,combined with the software of ABAQUS to complete the simulation analysis of xin-long tunnel,which undered different orthe different steps of excavation,especially for the jiu-ting center grain depot locations that xin-long tunnel will pass under it,in order to got more safe and effective construction method.