**9.9 Conclusion**

Acceptances and geotechnical investigations carried out during the tunnel design phase are limited. All tunnel projects are made with these deficiencies and in a sense, they are in the form of a preliminary project. It should never be possible to go with uncertainties and to implement the same support systems made in the design phase. Geotechnical measurements and project data should be continuously evaluated and revised according to the encountered geological conditions.
