Multi-Plate Corrugated Steel Rock-Fall Tunnel at Km 311+550–311+700, Irmak–Zonguldak Railway

In the area of the Irmak–Zonguldak railway known as the tunnels section, between Km 311+550 and 311+700, a 150 m long, 5.85 m high epoxy-coated multi-plate corrugated steel tunnel was built to protect the line against rock fall. Carried out without interrupting rail traffic, it was a pioneering project in Türkiye. Alongside the tunnel, an 80 m long, 8 m high stone wall and ballast retaining wall were built. Site access was only possible by placing eight rows of 2×2 m precast culverts in the constantly flowing stream and rebuilding the crossing after every flood. The work for the TCDD 2nd Regional Directorate also involved 30,000 m³ of excavation and fill.

Scope of work

• 01150 m long, 5.85 m high epoxy-coated corrugated steel tunnel
• 0280 m long, 8 m high stone wall and ballast retaining wall
• 03River crossing with 8 rows of 2.00×2.00 m precast concrete culverts
• 0430,000 m³ of earthworks