Tertiary Sand Shale Tunnel Gushing Water Mud Paragraph Construction Plan Research

Tertiary Sand Shale is a kind of special strata which engineering characteristics of surrounding rock parameters is not clear.In tunnel construction that situation is the serious influence of the engineering quality and the construction schedule for rock with water is easy to collapse.This article is based on MUSUI line ShuangFeng tunnel construction engineering background,using the finite element numerical simulation method to tertiar y sand shale formation mud gushing water segment of tunnel excavation construction methods for the selection and optimization.Further through the numerical simulation analysis to select the optimal excavation scheme.Paper main research work and achieveme nts are as follows:(1)In view of the tunnel gushing water mud geological disaster area,respectively from the terrain,formation of surrounding rock and groundwater,atmospheric precipitation and other aspects of research and construction of excavation t unnel gushing water of the main causes of mud,and combination of waterproof and drainage technology which form home and abroad,to deal with the tunnel gushing water processing of geological disasters.(2)To monitor measurement the construction of tunnel gushing water mud.Respectively on the top of tunnel,right and left haunch,right and left flank wall,right and left arch springing,all the seven points to embedding pressure box,installation of steel strain gauge,concrete strain gauge and steel bar strain gauge to monitor.Through analysis of monitoring data that we can get the deformation of surrounding rock stress and the relationship between the supporting parameters.(3)Using finite element simulation method of the CD method and three steps middle of wall method for numerical simulation and analysis,to choose optimal excavation scheme selection of the tunnel construction.N umerical simulation study three steps middle of wall method has control of tunnel vertical deformation,reduce the disturbance of surrounding rock and initial support stable performance,suitable for large mechanical construction,the construction of the advantages of high safety,so choose three steps middle of wall method as the excavation construction scheme of the tunnel.(4)The use of finite element simulation for initial support scheme supporting parameters of the diameter of Lock foot anchor,Steel arch model,and the beginning of shot Crete thickness for optimization analysis.It is concluded that it is more conducive to the tunnel deformation control when use the supporting parameters of the diameter of lock foot anchor of d=89mm,Steel arch model I22 a,and the beginning of shot Crete thickness of h=30cm.(5)Use numerical simulation method in tunnel gushing water and mud for drain step-down technology research,numerical simulation analysis,form the two sides of the surface precipitation well and flat guide drain.Studies have shown that the surface precipitation well displacement of 900 m3/d Is greater than Flat guide drain displacement of 600 m3 /d,and Surface precipitation well pore water pressure of 0.9 MPa is Less than Flat guide drain the pore water pressure of 1.15 MPa,So choose the surface precipitation well as tunnel drainage decompression technology solutions.