Helsinki Metro Achieves 60% Reduction in Equipment Maintenance with Barchip’s Synthetic Fiber Shotcrete Reinforcement
The Helsinki Metro System is currently undergoing a major expansion from Ruoholahti to Matinkylä in Espoo via Lauttasaari and is Finland’s largest infrastructure project.
The expansion consists of 13.9 km twin tube tunnels, 6 m diameter with connection tunnels every 150 to 170 m. Seven new stations will be built along the line with a further station planned for Niittykumpu. Upon completion the west metro will transport over 100,000 passengers every day. The entire metro system will be a fully automated, driverless system.
The estimate for the overall project cost, drafted at October 2007 prices, is €713.6 million, shared approximately 72 % /28 % (Espoo/Helsinki), with the government taking over 30 % of the metro costs.
The Helsinki West Metro extension has a number of subsea sections which rained serious concerns over the corrosion and durability of steel fiber reinforcement. As a result, the original specification of 40 kg/m3 of steel fiber was changed to 7 kg/m3 of BarChip54 synthetic fiber shotcrete reinforcement.
The change to BarChip structural synthetic fiber also delivered owner Lansimetro an 82.5% reduction in handling, storage and transport of fiber materials and a 66% reduction in wear, tear and maintenance of shotcrete equipment.
BarChip structural synthetic fiber reinforcement was specified for the shotcrete support lining after achieving the specified 1000J (EFNARC) at the lowest cost per Joule.
- Estimated cost € 713.6 million
- Largest construction project in Finland
- 9 km twin tube tunnels 6 m diameter. Connection tunnels every 150 to 170 m. Comprises 7 new underground stations
- Drill and Blast tunnelling method.
- Initial mix of steel fibers was changed to BarChip synthetic fibers due to corrosion of steel fibers, cost advantages, performance and availability
- BarChip achieved 1000J EFNARC specification with the lowest dose rate and lowest cost per Joule
- BarChip offered a c.82.5% reduction in handling, storage and transport of fiber materials
- BarChip offered a c.66% reduction in maintenance of shotcrete equipment, particularly hoses and nozzles.
- BarChip offered a c.70% reduction in carbon footprint.
- Reinforced with BarChip structural fibers