SH. Taheri - Ms.c Rock mechanic engineering and academic member of azad university of Mashhad
H. Saghi - PhD Student of Hydraulics, Department of Civil Engineering, Ferdowsi University, Mashhad, Iran and designer of TOOSAB consulting engineering company

The purpose of this research is study of stability of water diversion tunnel of Ardak dam of Mashhad and analyzing it through the experimental and numerical methods and finally providing different methods and controlling stability of tunnel housing based on regional strategic situation. For this purpose, at first the condition of regional geology determined thorough ground experiments and cross-drilled bore tunnels and exploration, and then suitable options identified to determine location and depth of the tunnel. Then specific parameters for designing tunnel were determined and designing the covert tunnel is accomplished by using various soft wares (including software and UNWEDGE and PHASE2) which are based on Finite element methods, and wedge method. Finally, the achieved results were validated through experimental analysis (RMR and Q methods) and providing the amount required for increasing the stability of tunnel maintenance has been proposed through natural sustainability of land.

Ardak dam, Finite element, Boundary element, stability of tunnel