**Abstract**

Tunneling is considered to be among the most important projects in all countries worldwide. However, interspersed, some tunnels rise to problems of instability during excavation. This chapter is a case study of the tunnel of "Djebel El Kantour" which is part of the East–West Algerian Highway. Face stability is the most critical problems that affect the subject of our research. This study is carried out via analytical and numerical methods based on the instability relationship, characteristics of the ground and the geometry of the tunnel, to draw conclusions and recommendations for overcoming this problem.

**Keywords:** replace stability, tunnel face, convergence, confinement, soil characteristics, excavation
