2002-2003 Sevan-Dilijan Road Tunnel Construction

The tunnel construction works were recommenced after a very lengthy standstill, that had a negative effect on the structures constructed earlier. The works were conducted simultaneously from Northern and Southern Portals. The driving of tunnel at the stretch of about 200 m length was executed under utterly complicated mining-and-geological conditions that required special drifting methods with segregated-phase mining of rocks, strengthening of temporary roofing. The lining of tunnel in earlier constructed sections and the ceiling of air ducts have been reconstructed. The works on waterproofing and on drainage system, on the roadbed in the tunnel and the adjoining areas, ventilation system, electric lighting, traffic safety and control of the flow of traffic have been executed.

The works implemented on outer engineering networks, communications and structures include:

1. Construction of buildings for the maintenance and security staff;
2. Laying of 35 kV transmission line and installation of substations;
3. Construction of the pumping house, ventilation building, etc.