Research On The Supporting Of Unfavorable Geological Tunnel Portal

In tunnel engineering,people have always regarded the portal engineering highly,because runnel portals are always located at the comlex geography condition ground.Auxiliary construction methods are needed to reinforce it and it for-med a directive method that is" Getting in hurry and getting out slow".The paper discusses the employing condition,mechanical principle,reinforce effect and construction requirements of various anxiliary construction methods in surface ground and inside tunnel,then summarizes the design parameters.The background of this paper is Dashantou and Changfenggou unfavorable geolgical tunnel portal engineeing.Using FEM simulation by GTS software,the paper makes mechanical analyses on the tunnel partal.Through the analysis of rock deformation, internal forces as well as the supporting structure of the forces,the paper determines the location where the project accident occurred at offenly and main points to support.At laat,combined with the monitoring of the final measurement data the conclusions and reliability of the conclusions of the paper will be proved.And the Chang-fenggou tunnel support design is optimized.