As part of the Ulus Historic Urban Area Renewal Projects, a 2×2-lane twin-tube highway tunnel was designed to connect the Mamak (Gülveren) – Aydınlıkevler road beneath Hıdırlık Hill.
The project was completed in 6 months in 2010. The client was Yapı Merkezi.
The new Ulus Tunnel runs mainly through andesite, occasionally passing through weathered rock zones. The tunnel was designed to be built by drill-and-blast, with excavation and support systems determined according to NATM. At-grade junctions were also designed before and after the tunnel.
Pedestrian traffic in the project area was studied as well, and sidewalks and safe pedestrian crossings were designed to maintain existing pedestrian circulation.
Topographic and geological-geotechnical surveys were provided by the client. Information on existing and planned utilities was obtained from the relevant authorities, and the tunnel cross-section was designed taking these utilities into account.
