— Project Description:

The project involves the upgrade to 4 lanes of a portion of 41km of length on NH-1A (between km89 to km130), including the construction of the Patnitop Tunnel (13.3m of diameter) and the parallel escape tunnel (6.4m of diameter). The excavation of the main tunnel was carried out simultaneously from both portals by conventional Drill & Blast method. The final optimized alignment needed to be compatible with any future increased capacity of the tunnel passing to a twin-bore solution. The layout includes pedestrian and vehicular cross-passages between the main and escape tunnel, lay-bys placed alternately at each side of the tunnel in the main tunnel and technical niches. Cross-passages are located every 300m (every 1200m a vehicular cross-passage is provided). Two complex junctions with toll station are provided at each portal to connect local roads.

— Description of Services:

Detailed Design, including Geotechnical Monitoring, MEP system design, and Construction Follow-up.