Research On Deformation Control Technology Of Weak Surrounding Rock Of Tunnel

In the process of tunnel construction,the soft surrounding rock environment has a very important influence on the design safety and construction quality of the tunnel project and the construction safety effect.At present,for tunnel construction in soft surrounding rock environment,there are usually large deformation,long construction period,high cost,prone to collapse and other safety accidents.With the continuous development of China's tunnel industry,the use of traditional methods to complex geological soft surrounding rock environment and the safe excavation of large scale tunnel has appeared a bottleneck,leading to the increasing incidence of underground engineering accidents in China.In this paper,geotechnical control deformation analysis method is mainly adopted to study soft rock tunnel excavation and construction and deformation control and other issues,including the following aspects:(1)through access to relevant information,the definition of weak rock,the characteristics of weak surrounding rock and various mechanical properties and deformation in the process of surrounding rock in tunnel excavation situation,engineering effect was studied,and combined with weak surrounding rock classification status,for different categories of weak surrounding rock engineering construction strategies are studied,and the basic concept of weak surrounding rock are the basic grasp with relevant theoretical knowledge.(2)through to the weak surrounding rock deformation control method and the supporting structure design principle is analyzed,respectively for forepole constraints(control deformation and vault subsidence in advance)constraints,it is support constraints(control extrusion deformation)and primary support behind the constraints of excavation deformation(control)was studied,and with the aid of auxiliary support measures,reserve constraints of weak surrounding rock stability reasonable supporting structure safety reserve status and residual deformation after the completion of the tunnel is studied.(3)based on the cases of taoshuping tunnel of lan-yu railway and tianpingshan tunnel of gui-guang railway,this paper studies the control practices of the deformation of the tunnel in front of the palm face and behind the palm face in soft surrounding rock.The engineering construction shows that the deformation of surrounding rock is effectively controlled.