Screw injection piles: vibration free, displacement pile

The screw injection pile is, basically, a steel tube pile encased in hardened cement grout. During installation the ground is wholly displaced, thereby increasing the bearing capacity. The steel tube is installed by screwing, whilst simultaneously injecting cement grout. During the installation the grout acts as a lubricant, which temporarily reduces driving resistance. When set the cement grout increases the strength and stiffnes of the pile, transfers part of the loading to the ground and gives corrosion protection to the steel tube. The steel tube is filled with either cement grout or concrete.

Main features of screw injection piles

• Steel shaft is screwed into the ground, resulting in:

• Vibrationless installation;
  
• Displacing the soil (no ground upheaval, no reduction in cone resistance values);
  
• Enlarged pile toe;
  
• Steel shaft makes the pile suitable for dynamic (tensile) loading situations;
  
• Steel shaft has a relative large steel section providing stiffnes/ rigidity of the pile (anchor piles);
  
• Pile head design and cement casing protects pile against corrosion;
  
• The pile can be installed anywhere (depending on soil conditions) but, because it is segmental, it is particularly suitable for use in situations with restricted access or headroom.  

Applications of screw injection piles

• Renovation works
  
• Operations within existing buildings / works close to adjecent buildings, old quaywalls, etc. / piling to strengthen or renew foundations (underpinning);
  
• Working heights or headroom clearance of minimum 4.0 m feasible (depending on proposed details);
  
• Reconstruction works
  
• In industry, roadworks or close to water-retaining structures;
  
• New buildings
  
• Close to vibration-sensitive premises / close to installations and buildings containing vibration sensitive equipment;
  
• Special applications
  
• Piling in connection with transmission masts, advertising structures, machine foundation, etc.;
  
• Anchor or tension piles;
  
• Strut piles;
  
• Piles with limited elastic behaviour;
  
• Piles with tensioned structures.

Source: www.walinco.nl