Project
Construction of “Lozarevo” tunnel and modernization of the associated Railway infrastructure
Contracting Authority
National Railway Infrastructure Company (NRIC)
Location
Karnobat–Sindel Railway Line, Lozarevo–Prilep Section, Burgas Region, Bulgaria
Period of implementation
august 2024 г.
Glavbolgarstroy’s role in the project
Main Constructor
Nature of works
The project forms part of the Double-Tracking and Electrification of the Karnobat–Sindel Railway Line and covers Lot 1: Completion of Tunnel No. 1 in the Lozarevo–Prilep Section.
Technical characteristics
- Execution of tunnel excavation works in rock formations using the drill-and-blast method.
- Execution of tunnel works in Pliocene clay formations and stabilization of the emergency section, with a total length of approximately 170 m.
- Construction of a cut-and-cover tunnel section with a total length of 216 m.
- Construction of tunnel portals:
- Entrance portal (Lozarevo side – south) – 20 m;
- Exit portal (Prilep side – north) – 12 m;
- Entrance portal for the emergency evacuation gallery.
- Construction and installation of the tunnel safety system, including:
- Excavation and construction of an emergency evacuation gallery with an approximate length of 1,888 m, including one entrance portal;
- Construction of cross-passages connecting the main tunnel and the evacuation gallery, located at approximately 500 m intervals along the tunnel alignment, each with an approximate length of 30 m;
- Construction of fire-fighting access areas at the entrance and exit portals, including earthworks and crushed-stone surfacing;
- Construction of access roads to the fire-fighting facilities, including earthworks and asphalt pavement.
- Waterproofing of the tunnel lining in sections affected by groundwater infiltration through the secondary lining of the completed tunnel sections.
- Rehabilitation and adjustment of the tunnel invert slab and communication ducts within the existing tunnel sections.
- Completion of the Patomishka River regulation works in the area in front of Portal No. 2 and construction of a bridge at km 22+420.
