The drilling rig had to be set up on a narrow section between the underground (metro) track belonging to Gemeentelijk Vervoer Bedrijf Amsterdam and the railway track belonging to ProRail parallel to the Schinkelbrug bridge. From this location two HDD’s were performed. The first had a measured distance of 336 metres. The second bore, measuring 356 metres in length, was drilled alongside the ProRail track and the A4 motorway. On successfully completing the pilot holes and reaming phase a bundle of 13 PE ducts (9x Ø 90mm PE and 4x Ø 125mm PE) were pulled in to each bore. During all drilling operations both tracks remained in use throughout the HDD works!
The only way to get the 27-tonne rig and all the ancillary equipment to the location was to lift it over the tracks directly into the required position. For the first HDD all equipment was prepared and installed during a rail track shutdown on Saturday 21 June, with the first drill being executed without incident and all equipment being removed again by 01:30hrs on Monday 1 July at 01:30. A similar schedule was also applied to the second HDD. This meant there was no room for error and the drilling needed to be completely on time as per the per the planning which it was to everyone’s delight.
Thanks to the excellent cooperation with sister companies VSKR (Volker Stevin Kabelwerken Railinfra) and the VolkerRail/VHB (Van Hattum en Blankenvoort) consortium, the schedule was met. VSKR and VHB ensured that the working area was optimised for the HDD process. Furthermore, they arranged that it was possible to turn the rig in the limited working area. All necessary cables and wires ran through three pipes under the track. In addition, VSKR saw to it that there was sufficient space on the exit side of the drilled holes to lay out the pe ducts in one continuous length.
This once again shows different divisions of the VolkerWessels group can achieve great things when working together with the client fully satisfied with the works.