ICE NL visit to Rokin subway station
On Saturday the 29th of September the Dutch Branch of the ICE organized a site visit to the Rokin subway station of the new North – South subway line in Amsterdam, the Netherlands. The visiting members were hosted by Joep Houtenbos en Tonny Johanna of the Rokin construction team.
The North – South subway line has been under construction for several years and runs underneath the historic city centre. The new subway line is built using sunk and bored tunnels, and several underground stations along the route. On completion, the subway will link Amsterdam North to the the rest of Amsterdam, which are separated by the IJ channel. Currently only ferry services and a road tunnel connect these parts.
The Rokin Station is a large underground station made of reinforced and self-compacting concrete. Tonny, the concrete technology expert on site, started the visit by giving a presentation on the application of self-compacting concrete in this station, and how this technology has developed and improved rapidly in the Netherlands over the last few years. The choice of self-compacting concrete is based on the size of the walls (up to 3 m thickness) and the dense reinforcement required making the station water tight. The construction time is reduced by not having to compact the concrete manually during the pouring of the concrete.
The station runs to a depth of 25 m. The top part of the structure will be used for car parking, trying to relieve the parking problems in the city centre.
After the presentation, the ICE members were allowed to visit the station under construction. Descending from a temporary stairs, the group was guided through the immense space underground. The concrete structure under construction still allowed a good view on the large steel props holding the walls, floors and ceilings in place until the station is completed.
Janwillem Breider, ICE Graduate Member in Amsterdam