Study On Deformation Characteristics And Control Techniques Of Sericite Schist Tunnel Construction

Sericite schist is a kind of metamorphic rock with sericite and chlorite as the main mineral composition.In the tunnels under construction through sericite schist,large deformation of surrounding rock is common,the supporting structure is damaged,the section boundary is invaded,and the tunnel will collapse or even be completely blocked due to improper handling,which is very easy to cause serious consequences,and the mechanical equipment will be damaged,causing casualties,construction delay and increasing project cost.In this paper,the deformation characteristics and control techniques of sericite schist tunnel construction are studied by theoretical analysis,laboratory test,field test and numerical simulation.The work completed in this paper mainly includes the following aspects:1、The physical properties of surrounding rock of sericite schist tunnel are studied by means of microstructure test,physical property test and hydrology property test.It provides a basis for analyzing the deformation characteristics of white stone tunnel and its influencing factors and provides basic parameters for the numerical simulation of sericite schist tunnel.2、Advance geological forecast in the construction site,monitoring,measurement and field test,and combining the method of numerical simulation of silk mica schist tunnel deformation characteristics of surrounding rock during construction period are studied,this paper analyzed the deformation characteristics of surrounding rock,white stone white rock tunnel is studied the mechanism of large deformation occurred,and white stone tunnel surrounding rock deformation during the construction influence factors are analyzed.3、This paper collects and enumerates the typical cases of large deformation tunnel of soft rock at home and abroad,analyzes the basic concept of tunnel deformation control,and studies the deformation control technology of surrounding rock during the construction period of sericite schist tunnel by means of numerical simulation.Through the comparison of different excavation methods,than choose the suitable for silk mica schist tunnel excavation method,the anchor length and arrangement is optimized,proposed the bolt arrangement that gets on next short length,the advanced small pipe and optimized the layout,the length of the numerical simulation results show that the method in this paper,the excavation and supporting structure optimization and effective control of the deformation of surrounding rock.