“Hellend Veld” acoustic screen in Apeldoorn

The “Hellend Veld” acoustic screen is located along the Deventer–Apeldoorn railway line in the Hellend Veld district of Apeldoorn. ProRail commissioned the screen, which was to be positioned along the railway track beside the new housing development of Hellend Veld.

Client:
ProRail
Location:
Apeldoorn
Apeldoorn1
Apeldoorn2
Apeldoorn3
foto 005

Project

The acoustic screen was installed by Strukton Infratechnieken. The screen is around 1,500 metres long and has a variable height of 2.3 metres to 3.3 metres. The screen follows the (curved) contour of the railway track and is made of steel uprights with prefab concrete screen elements. The entire structure has a foundation of steel tube piles with concrete column bases.

The prefab screen elements were designed and produced by Strukton Prefab. These screen elements consist of a layer of structural concrete and a layer of sound-absorbent concrete (Loporton) specially developed by Strukton Prefab. The element has grooves on the railway side. The unusual thing about this element is the use of the sound-absorbing concrete and the fact that the two types of concrete are poured into the mould straight after each other. The layer of sound-absorbing concrete is poured first into the mould with grooves, after which the layer of construction concrete is poured. The elements are 4 metres long and 1,000 mm or 750 mm high. By stacking the two screen elements in different ways, the variable height of the acoustic screen can be followed.

An alternative in the specifications involves using steel tube piles for the screen foundation instead of concrete piles. The steel tube piles are vibro-driven 6 metres into the ground by a hydraulic crane with a vibration block. This method was initially chosen because of the short preparation time required. The long delivery period for the concrete piles would have delayed the project, whereas the tube piles were available directly from stock. An added advantage of the tube piles is that shuttering does not have to be used for the concrete column bases. This is because the cages of the column bases are suspended and poured directly into the excavation head of the tube pile.

To finish the screens, plant netting was fitted on the track side of the screen and hedria was planted in the groove along the entire screen. On the other side of the acoustic screen (residential side), a waterway was dug and fencing was positioned.