DSI supplies 1,820 Permanent GEWI® Anchors for A 4 Motorway Construction from Delft to Schiedam
The plan to close the gap on the A 4 between Delft and Schiedam in the South-West of the Netherlands in order to create an efficient connection from The Haag to Rotterdam dates back to the 1950’s. However, the implementation was delayed several times and finally started in 2012 on the authority of Rijkswaterstaat, a department of the Dutch Ministry for Infrastructure and the Environment.
The gap on the A 4 is being closed by a 2km long tunnel as well as a 4km long, depressed road section. The recessed area is an open box construction that is being built within an artificial landfill cell. Cement-bentonite walls with sheet piles are constructed in the watersealing clay layer in the jobsite area, creating a 1.5km long watertight dam.
Due to the excavation depth of 13m, the sheet piles had to be stabilized against uplift and safely anchored. For this purpose, DSI Netherlands produced and supplied 1,820 corrosion protected, permanent 63.5mm Ø GEWI® Anchors. The anchors supplied by DSI had lengths ranging from 19 to 41.5m because of the variable and unstable soil conditions.
Each of the 1,820 permanent GEWI® Anchors was subjected to a control test by DSI in cooperation with the subcontractor Volker Staal en Funderingen B.V. The applied stressing forces varied from 607kN to 1,284kN. The subcontractor also installed the anchors. In total, approx. 50km of GEWI® Anchors were installed for closing the gap on the A 4 Motorway.