ABSTRACT
In order to design a large diameter surge shaft, headrace tunnel and passageway connection, it is required to perform effective numerical analyses to calculate the successive stress distributions and plastic deformations in rock. This paper investigates the structural response of vertical shafts considering interaction with rock mass by a various numerical modeling technique. The main objective of this study is to define a realistic and comprehensive approach to the design of vertical shafts. An axisymmetric and a plain strain nonlinear analyses have been conducted by using finite element codes as Plaxis 2D and Phase 2 to predict the response of rock mass around the shaft. Since geometry is 3-Dimensional, a 3D finite element program called Midas GTS NX has been used to investigate the accurate behavior of shaft excavation. The calculated displacements and plastic zones around the shaft by numerical simulation results have been evaluated and interpreted.
