Application Research On Advanced Geological Prediction Of Micangshan Tunnel Based On Geological Radar

With the rapid development of tunnel engineering in China,the safety construction of tunnels has attracted more and more people's attention.Ground penetrating radar(GPR)has been popularized in advanced geological prediction and lining quality detection of tunnel engineering because of its fast detection,convenient,high efficiency and no damage.In the present stage,the accurate prediction of unfavorable geology and the determination method of the surrounding rock grade in front of the tunnel excavation section are an important subject.In this paper,the ground penetrating radar(GPR)is used to determine the surrounding rock grade of the Mi Cangshan tunnel and the interpretation marks of the plastid radar images in the quartz diorite section,based on the actual project of the Mi Cangshan tunnel.On the basis of ground penetrating radar theory and related research principle,through the research section of ZK53+373-ZK53+343 section in tunnel,this paper focuses on the determination method of surrounding rock grade which is the most frequent change of surrounding rock in grade Mi Cangshan tunnel.In the study period presents a joint determination method of rice in Mi Cangshan tunnel,the ground penetrating radar geological prediction qualitatively determined by grade of surrounding rock and tunnel convergence prediction period of deformation monitoring and measurement work obtained the actual rock deformation curve forecast period,based on the existing tunnel surrounding rock convergence model,the application of data mining the software SPSS(Statistical Product and Service Solutions)for the inversion of measured data by correlation and regression analysis,fitting quantitative analysis on surrounding rock grade were analyzed,finally,to ensure the clearance convergence data to reflect the deformation of surrounding rock and tunnel lining quality of section of gpr.In order to ensure the correctness of the joint determination method,the corresponding provisions of the basic norms of quality index of intermediate rock on rock grade proposed joint determination results verify the results are consistent with the specification of intermediate surrounding rock,the tunnel surrounding rock deformation parameters and simulation analysis of ABAQUS inversion inversion of SPSS regression analysis results were verified.Then the method is applied in four application segments,and good results are obtained.At the same time,the characteristics of radar images in the ground penetrating radar in advance geological prediction are summarized and analyzed.The main results of this paper are as follows:(1)Quantitative analysis of the prediction of ground penetrating radar(GPR)advanced geological prediction,field monitoring measurement and measured deformation data inversion,regression analysis correlation and fitting,combined with the joint judgment method of the earth rock grade of the Mi Cangshan tunnel under the non destructive testing of ground penetrating radar lining.Joint decision method put forward in this paper,the classification of surrounding rock in period of application has achieved good results,show that the method can be extended to quartz diorite and Mi CangShan tunnel section with similar geological structure of tunnel for the determination of grade of surrounding rock.(2)Mi CangShan quartz diorite rock tunnel variety of geologic body on radar image interpretation signs and response characteristicsis was established,and can provide reference for the similar tunnel advance geological forecast interpretation of ground penetrating radar.