3816

3608

كارشناسي ارشد

خاك و پي

اصفهان : دانشگاه صنعتي اصفهان ، دانشكده عمران

1386

ده، 119، [II]ص: مصور، نمودار، جدول

ص.ع. به: فارسي و انگليسي

محمود وفائيان

30/10/86

محمود هاشمي اصفهاني، بهروز كوشا

مهندسي عمران

ID3608

به فارسي و انگليسي : قابل رؤيت در نسخه ديجيتال

AbstractWhen tunneling through poor ground conditions or if there is a shallow ground coverabove the tunnel crown the rock or soil mass needs to be reinforced a head of the facebecacuse the tunnel displacement causes deformation of the ground between thetunnel and the ground surface and hence results in subsidence at the ground surface The Umbrella method is a ground reinforcement technique in which all or a part of atunnel section is placed before beginning excavation The aim of the Umbrellamethod is to form an Arch like shell of grouted and or reinforced rock and soil massaround the tunnel The Umbrella method has advanteges in certain conditions wherethe overburden is shallow or where the ground deformation needs to be restricted This thesis discusses the potential of using steel pipes around a tunnel to enhance thestability of the tunnel prior to tunnel excavation An Implicit finite element analysis ABAQUS was employed to evaluate the effect ofthe steel pipe roof on ground surface settlement and deformation at the tunnelface The numerical results indicate that the tunnel roof formed by the steel pipesprovide a restraining effect on the tunnel induced displacement and helps to reducethe tunnel deformation and corresponding ground surface settlement

محمود وفائيان

محمود هاشمي اصفهاني، بهروز كوشا