SUMMARY
The Rock Mass Rating method applied in the Project of the H¶i V©n Col Tunnel
NguyÔn Ngäc N¨ng
In the realization of the Project of the H¶i V©n Col Tunnel the rock mass rating has been carried out on the main basis of the RMR system of Bieniawski with some small modifications in accordance to the applied confines and the support equipment. In the paper the author presents this system with some modifications expressed in the tunnel construction method of Austria.