Free travel in Amsterdam - with innovative fastening technology 06 April 2020

The longest and second-widest land tunnel in the Netherlands is currently under construction, in order to channel traffic in Amsterdam Southeast more underground - and thereby reduce noise and air pollution for the benefit of local residents. Over 1.7 million fischer nail anchors FNA II in stainless steel (A4) have been used to attach fire protection panels to walls and ceilings as well as for other applications.

The state road manager is currently having the highway 9 in Amsterdam south-east expanded as the client (Rijkswaterstaat). The construction project is part of the Schiphol-Amsterdam-Almere (SAA) project in the Netherlands, which aims to increase the capacity of several expressways (A1, A6, A10 and A9) and thereby better develop the Randstad area. The A9 Gaasperdammerweg between the intersections Holendrecht and Diemen will be expanded from three to five lanes in each direction plus one alternate lane.

Part of the project is the new tunnel, which will be three kilometres long after completion in 2020. It is the longest land tunnel in the Netherlands. Another special feature is that the underpass can be left halfway through local transport. With a width of 73 metres, it is also the second widest land tunnel in the Netherlands.

Two tunnel tubes located on the very outside are being created for local traffic to and from Amsterdam south-east. In addition, there are two interior locations for through traffic. A fifth tunnel tube is provided for the alternating lane. The underground, central traffic artery is designed to reduce noise pollution for residents on the A9 and improve air quality. A park is also being built on the roof of the tunnel and is scheduled for completion in 2021. The green area is intended to connect the neighbourhoods in Amsterdam-Zuidoost with each other and to further improve the quality of life there.

The fischer group of companies has already successfully completed the fastening of the fire protection panels to the walls and ceiling in close cooperation with the construction company Kaefer Construction GmbH. The purpose of retrofitting tunnel clothing is to protect the concrete structure in the underground traffic system in the event of a fire. "The type of fire protection, whether panel, fire protection plaster or paint was determined in advance. The focus was placed on, among other things, the service life, visual appearance, economy and duration of installation,” explains Sven Burgard, head of passive fire protection for buildings and tunnels at Kaefer Construction GmbH.

In the end, the system was tested in several fire tests to ensure its suitability. The fischer nail anchor FNA II A4 with a built in number of more than 1.7 million was used. "The fact that our FNA II A4 is demonstrably ideal for tunnel fire protection and that it can be processed easily and quickly was one of the quick arguments. The FNA II also meets the high requirements for wind suction loads and longevity in the project and is also suitable for sensitive concrete as anchoring base,” emphasises Daniel Jäger, head of industrial key account management at fischer Deutschland Vertriebs GmbH, who was instrumental in accompanying the project.

Few installation steps were sufficient for the execution - the fire protection plate was simply positioned on the wall or ceiling, create the drill hole through both and then place the dowel in a push-through assembly using a compressed air tool. The FNA II spreads automatically when loaded. The cone is pulled into the expansion clip and braces it against the borehole.

“The FNA II is very well suited for this application because it is very easy to process. Simply drill the hole, drive in the nail anchor - and you're done. Once set, it guarantees its function for a very long time,” confirms Sven Burgard.

The FNA II A4 has already been used several times in the Netherlands in the area of fire protection. It has proven itself in numerous projects. The anchor has successfully passed all fire tests by the fire protection board manufacturers. "In addition to the timely production and delivery of the large number of FNA II as the ideal fastening solution, our wide range of services also made the difference," emphasises Daniel Jäger. "This is how we successfully accompany our customers through all project phases - from planning and calculation to pull-out attempts in advance to on-site support through training and certification of the contractors."

Claire Aldridge Deputy Editor t: +44 (0) 1727 743 889

Having spent a decade in the fastener industry experiencing every facet – from steel mills, fastener manufacturers, wholesalers, distributors, as well as machinery builders and plating + coating companies, Claire has developed an in-depth knowledge of all things fasteners.

Alongside visiting numerous companies, exhibitions and conferences around the world, Claire has also interviewed high profile figures – focusing on key topics impacting the sector and making sure readers stay up to date with the latest developments within the industry.