FK Lowry offers a full range of Piling Techniques. We have many years’ experience using these techniques in providing cost effective foundations solutions.
Rotary Bored Piles
Rotary bored piling methods are used when the large diameter piles are required to provide high load capacity or for dealing with difficult ground conditions such as boulders and rocks. The system uses a telescopic Kelly bar and temporary steel casing where necessary. When the pile is bored to the required founding strata a reinforcement cage is inserted and the pile is usually concreted using the tremmie technique and the temporary casing is removed.
FK Lowry Piling has carried out bored CFA (Continuous Flight Auger) piling since 1990. This is a low noise and vibration free system in comparison to Driven Piling. The method involves drilling the pile to a design depth and pumping high slump concrete through the central auger stem as the auger is withdrawn. The system is controlled by on-board computer which measures depth, concrete flow, torque and pressure. Given that the bore is supported by the augers during pile construction it eliminates the requirement for temporary casing support fluids and is therefore particularly well suited to waterbearing ground conditions. Reinforcement is installed after concreting operations are completed by plunging or vibrating the cage into the wet concrete.
CFA piles are installed using our Soilmec SF65 for pile diameters between 300mm and 750mm diameter. For pile diameters above 600mm the higher torque Soilmec SR95 and Soilmec SR75’s machines are used for installation.
Driven Precast and Steel Piles
Driven piles represent our original core product with more than 30 years’ experience in the UK and Ireland. Our driven piles may be Steel H, Steel Sheet, Steel Tubular or Precast Concrete.
Driven piles are an economical piled foundation in comparison with some other systems available on the market. It is a ‘displacement’ system in that the existing soils are ‘displaced’ in the ground by the pile being driven in rather than the soil being removed from the ground by boring of the material. This is one of the many advantages of using driven piles in that there is no spoil to be removed from site. Others advantages include:
- Off site manufacture of the piles under controlled factory conditions
- Direct loading capacity being determined whilst the pile is installed
FK Lowry has invested in the modern and highly reliable purpose built Junttan PM20 and PMX20 piling rigs. These rigs are capable of installing a variety of pile types, sizes and sections in order to deal with almost any loading condition encountered within the construction industry today. All rigs are fully instrumented with the latest NDT computerised recording system and provide real time data on length, set and rate of installation and additional records can be used in our QA management system.
Secant and Contiguous Retaining Walls
We have extensive knowledge and experience in installing retaining walls, both secant and contiguous. These walls can be constructed to tight tolerances close to existing buildings to maximise your basement size. FK Lowry is viewed within the industry as offering the full package from detailed design to successful completion of contracts.
Both types of walls can be designed to cantilever or propped (anchored external or internal) to restrict displacement of the wall. Secant walls will provide protection against water up to Type A in accordance to BS8102. Sequencing of installation is also of paramount importance in the installation of both types of wall.
These walls maximize the space of the basement footprint which is of increasing interest to developers as land prices continue to escalate. Also these walls can be designed to take permanent loads, both axial and moment, from the structure above reducing the need for internal columns within the basement.
Contiguous and Secant walls can be installed using our entire CFA Fleet. The selected rig is dependent on ground conditions and required pile size.
The size of the projects we have been involved in varies greatly but at present we have capabilities to install walls up to 900mm diameter with a pile length up to 25mtrs and a retained height dependant on ground conditions, maximum so far 14mtrs.
Bored Displacement Piles
Bored displacement piles are used where low vibrations and minimal spoil generation are important to project delivery.
Typically bored piles are selected due to low vibration during installation compared with driven displacement systems. However bored systems generally produce spoil as the material is removed from the bore and replaced with concrete.
Bored displacement piles have the advantage of low vibrations as they are formed by rotating and pushing a displacement tool into the ground, displacing the sides of the bore, in this way very little spoil is generated.
Bored displacement piling requires very high torque machines in order to screw the drill rods and tool into the ground. Not all ground conditions are suited to this type of piling and its use is generally better in granular rather than cohesive soils.
Bored displacement piles can be constructed using our Soilmec SR70 and Soilmec SR-75 piling rigs.
Precast Manufacturing Process
- Input materials are sourced locally and delivered to our Precast Pile Manufacturing facility in Lisburn.
- Casting of piles takes place under quality controlled processes using under mould heating systems for rapid curing.
- Each pile is given a unique bar code for traceability and stock control purposes.
- Piles are moved into stock piles for final curing.
- Our dispatch office manages the distribution of piles to our projects throughout the UK and Ireland ensuring efficient timely delivery to meet project needs.
Our plant investment also covers a wide range of quality equipment and fleet vehicles.