DPA-PLUS screw piles - Vroom Funderingstechnieken
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DPA-PLUS screw piles

The DPA-PLUS screw pile forms part of a cast-in-situ displacement screw pile system. The soil is pushed to the side so only a little of the disturbed soil can enter the casing. It is a low-vibration process, which is important where piles are installed close to adjacent walls that could easily be damaged by subsidence and/or vibrations.

Vroom Foundation Technology has built up a substantial body of experience with screw piles and can advise on specific potential applications for both this type of pile and other screw-pile systems.

Features of DPA-PLUS screw piles

  • Soil is displaced, so little disturbed soil either rises to the surface or is retained in the casing.
  • Low-vibration, i.e. suitable for use close to adjacent walls that could easily be damaged by subsidence and/or vibrations.
  • Low-noise, which means less disturbance in the surrounding area, and that the pile system is suitable for use in the vicinity of schools, public buildings etc.
  • The pile head is cast up to the working level.
  • The pile length can immediately be adapted to the nature of the ground.
  • Adjustment of pile specifications possible until just before the start of work.
  • Pile angles: tilting backwards 5:1 / tilting forwards 10:1.
  • May be subjected to both compression and tensile forces.
  • Reinforcement can be applied to the full length.
  • Reinforcement is applied in the lining tube before the concrete is poured.
  • The pile system is well-known and recognised by the Netherlands Building Control Committee and designers alike. Competitive in relation to displacement piles due to larger bearing capacity and a ‘clean’ building pit.

Areas of application

  • Particularly suitable for residential construction, non-residential construction and other new-build projects where disturbance to the surrounding area needs to be kept to a minimum.
  • Suitable for urban-renewal projects where foundations need to be installed close to adjacent walls or properties without vibrations.
  • They are an alternative to non-soil displacing screw piles where the soil that comes to the surface would seriously pollute the building pit, or where the resulting soil cannot or may not be removed.
  • They are less of a noise pollutant than driven pile systems and can thus be used when extending existing buildings and buildings that are in use.
  • Can be used where the nature of the soil or the pressure mean that a long reinforcement cage is required that can be centrally fitted to the pile with the required cover.

Quality control

Vroom Foundation Technology installs DPA-PLUS piles using a proprietary process devised as part of internal quality control and in line with nationally-applicable standards.

Monitoring geotechnical bearing capacity

The DPA-PLUS piles are installed to the correct depth using soundings. To do this, the required drilling torque is measured to assess and identify the depth of the foundations.

Monitoring pile bearing capacity

All DPA-PLUS piles are checked after installation by means of acoustic testing. Additional inspection can be made visually, once the pile head has been excavated. The grade of concrete used can also be checked by taking a sample from the concrete core of finished piles.

Allow us to advise you

We at Vroom Foundation Technology prepare our leaflets and website with the greatest possible care and attention. However, no rights can be derived from such content. If you use information from our leaflets or our website without verification or further advice, you are doing this at your own risk. Vroom Foundation Technology accepts no liability for the correctness and/or suitability of the information for the purpose you envisage. Should you have any questions about the use of our products for actual projects we advise you to contact our sales department.

Technical specifications


1. Positioning of DPA PLUS drill with hydraulic drill attachment.

2. The hydraulic rotary head turns clockwise through the intervening strata.

3. The hydraulic rotary head turns clockwise to the correct depth.

4. The reinforcement is installed to the required length.

5. Wet concrete is then injected into the stem of the screw pile.

6. Wet concrete is injected during the process up to at least 1m above working level. The tube is then retracted from the ground by rotating it anti-clockwise.

7. The pile can then be finished, before acoustic continuity testing.


B500B grade. Pile reinforcement and dimensioning are based on force data provided by the designer. Spiral rebar stirrups make for a significantly stiffer reinforcement cage, so less deformation. Shaft reinforcement is positioned to the correct height in the tube.


Pile base coefficient

αp = 0.63 for the external diameter of the pile (section III NOT reduced) β = 1.0

Shaft friction coefficient

αs = 0.009 for the external diameter of the pile (no reductions) Tension: αt = 0.009

Load and deformation behaviour

Within the scope of the forces to which the piles are exposed subsidence is almost equal to that of a driven pile.

Load spectrum

Compressive force up to approx. 2500 kN. Tensile stress up to approx. 400 kN.

We can advise on the load-bearing capacity of DPA PLUS piles for a specific soil composition/surface.


360/510, 460/610 en 560/710.

The pile length depends on the nature of the nature of the ground and forces to which the piles are subjected. We will assess the feasibility of installation depth and load-bearing capacity for piles.


Available in grades C20/25, C25/30, C30/37 and C35/45.

Default rsm 78 104
Can we help you with your project?

Contact Rob Sman. Dial +31(0)299 409 542 or send us an e-mail.

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