Numerical Analysis of Stress Distribution During Tunneling in Clay Stone Rock

Modern technology has been used to build tunnels in recent years by means of drilling machines (TBM) that were used for civil engineering work in large cities to reduce the harmful effects of spending on the surface of the earth significantly. To build the tunnel, numerical modeling was used on the basis of the finite element method to predict stress behavior during the tunnel construction process. Tunnel simulation model by using the numerical method (FEM) with the Hoek-Brown model, which includes calculating the behavior of predicting stress-that surrounds the tunnel and analysis during the process of building the tunnel and compared with the natural state of the rocks during the different tunnel construction stages. Vertical stresses at the top and bottom of the tunnel are reduced during the advance of tunneling while horizontal stresses are increased. TBM progression is reflected in phases through one to five by performing an axial symmetric FE analysis, math calculation results revealed significant stress changes occurring in rock regions near the boundary of the tunnel. In other words, proximity to rocks is mostly affected by the tunnel. These pressure variations decrease as you move away from the tunnel horizontally and the seams reach extremely small values for distances greater than (2D) meters from the edge of the tunnel, where D is the diameter of tunnel.