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In this study, stability of Pardis tunnel, east of Tehran, is analyzed by means of three dimensional profiles of displacements and stresses around tunnel. These profiles are obtained from numerical models created by FLAC3D software and provide complete insight about state of displacements and stresses around tunnel. By compare of these displacements with respect critical values, stability of tunnel could be assessed. Also in this study, state of support system in clay zone of tunnel was discussed and importance of support penetration in tunnel floor and effect of this phenomenon on tunnel stability was showed.