Underpass Reinforcement – Hisarönü–Zonguldak Highway, Kilimli Pass, Turkey
ViaCon delivered a corrugated steel structural solution to reinforce an existing highway underpass located on the Hisarönü–Zonguldak Highway at Kilimli Pass in Turkey. The project required a durable reinforcement system that could be installed efficiently in a challenging mountainous location while maintaining traffic flow.
Structural Design
- Number of structures: 2
- Span: 11.66 m
- Rise: 7.15 m
- Bottom length: 63 m
- Bevels: 1:1
- Skew angle: 90°
Project Background
In 2021, the Turkish General Directorate of Highways identified structural deterioration in an existing underpass tunnel along the Zonguldak Highway. Cracks and fractures had developed in the tunnel walls, affecting the structural performance of the structure and causing water leakage from the road surface.
Due to the strategic importance of the route and the high daily traffic volume, the reinforcement works needed to be executed with minimal disruption. The mountainous terrain and elevated site location also required a solution that could be transported and installed efficiently under difficult site conditions.
Engineering Solution
ViaCon Turkey proposed the installation of a ViaPlate corrugated steel structure as a structural support inside the existing underpass.
The modular steel plate system allowed the structure to be transported in segments and assembled directly on site. This approach minimized logistical challenges associated with transporting large, prefabricated elements and enabled rapid installation compared to traditional concrete reinforcement methods.
Once assembled, the steel structure provided a new load-bearing system within the existing tunnel, restoring structural safety while extending the service life of the underpass.
Structural Design
- Number of structures: 2
- Span: 11.66 m
- Rise: 7.15 m
- Bottom length: 63 m
- Bevels: 1:1
- Skew angle: 90°
Construction
Fabrication and installation of the steel structures were completed within approximately two months, under the supervision of ViaCon Turkey.
The modular nature of the system enabled fast assembly while maintaining traffic operations throughout the construction period.
Technical specifications
- Product: ViaPlate corrugated steel structure
- Design load: Eurocode LM71 train load
- Cover depth: 3 m under road surface
- Seismic conditions: Peak ground acceleration 0.239 g
- Design service life: 75 years
- Corrosion protection: Hot-dip galvanizing in accordance with EN ISO 1461
Project Outcome
The installation of the ViaPlate structure restored the structural capacity of the underpass while minimizing construction time and disruption to traffic.
The project demonstrates how modular corrugated steel structures can provide an effective reinforcement solution for existing infrastructure in challenging environments.