Engineering Management Measures And Monitoring Analysis Of Landslide Located In The Inlet Section Of Super Large Section Loess Road Tunnel

In recent years,most highway tunnels need to pass through various mountain ranges in the western region,and the tunnel through the mountain is the most convenient way.The study of super-large section highway tunnel and tunnel entrance landslide in loess area can be used for advanced prediction and prediction of loess landslide in the entrance section of the tunnel and provide important theoretical basis for the study of highway tunnel landslide prediction and treatment measures in loess area.With an expressway tunnel landslide in Baoji region of Shaanxi province as the research object,through on-site investigation,theoretical analysis,numerical calculation and field monitoring technology,discusses the large cross section of the loess highway tunnel landslide and the tunnel engineering of interaction relations,the analysis of the landslide control measures,and combined with field monitoring data are analyzed in detail,the research work mainly include the following:(1)Through the tunnel of the investigation and analysis on the engineering geological conditions,that the tunnel vault from the sliding surface of the left line of the vertical length of 0.5-14 m,most of the vertical distance from the sliding surface is greater than 5 m,the stress and deformation of the lining of the sliding body interference is small,local close distance sliding surface vertical distance,the stress and deformation of the lining of the sliding body interference is biggest.(2)The study of interaction mechanism of the landslide and the tunnel,the factors of landslide stability is analyzed,several influence factors of influenced the landslide disaster,and of the force deformation characteristics of landslide caused by tunnel theory analysis,get the deflection of the tunnel under the condition of stress,get the tunnel entrance "tunnel-landslide" interaction model.(3)The landslide at the tunnel entrance is relatively stable at the initial stage of tunnel excavation.When the working face is pushed to 50 m,the sliding displacement of the landslide increases with the increase of excavation distance.Falling behind,displacement rate increase with working face advancing,when face to monitoring period of decline rate reaches the maximum value,through the initial operation of the tunnel and secondary support,working face advancing to the monitoring period of 30 m,the landslide deformation basically stable.(4)Monitoring and analysis of the landslide in the entrance section of the tunnel are carried out by means of on-site monitoring and measurement.Controlled by the mechanical properties of the rock-soil mass,the interaction between the surface rock and the supporting structure significantly increases the surrounding rock pressure,and the final settlement trough at the point above the surface monitoring tunnel has obvious asymmetry.At the beginning of the tunnel construction,the settlement of the arch roof is relatively high.As the large section of the tunnel continues to go deeper,its support technology and anti-slide pile support effect become more and more obvious,and the settlement displacement of the cross section of the arch roof gradually tends to be stable.