Directors DDAG assess tunnels in Nepal
Two pressurised tunnels of lengths 7500 & 6000 m in central crystallines have been reviewed by DDAG Directors Dr Gopal Dhawan & Shri Yogendra Deva. Based on representative Q values and using the experience in Himalayan tunnels, final support requirements were assessed. These are expected to lead to considerable savings in the estimated supports. The Directors also made contributions in the general understanding of the engineering geological model of the two tunnels. In particular, where the tunnel was detou yet had to negotiate 80 m length in slide debris. Training in the installation of NRVs in tackling hydro static pressure has been another contribution.