Piling Services
We are proud to offer a complete package of piling capabilities to our clients, including installation and testing. Thanks to our network of specialist geotechnical engineers, we are able to offer optimised designs to maximise efficiency.
Whatever your project requirements may be, we have a piling solution to serve your needs.
CFA Piles
The Continuous Flight Auger (CFA) process is one of the quickest and most cost-effective methods of piling available. EA Piling offers CFA piles of up to 900mm in diameter and 25m in length.
Advantages: quiet, quick, economical, minimises settlement, can be installed in water-logged soils, does not require casing or bentonite.
Applications: load bearing piles, contiguous walls, secant walls.
Process: First, a hollow-stem continuous flight auger is drilled into the soil to the required depth. Then, concrete is pumped through the stem of the auger as it is removed to fill the cylindrical cavity. Finally, a reinforcement cage is inserted into the freshly placed concrete using the piling rig and a vibrator.
Rotary Bored Piles
Rotary piles represent the state-of-the-art method of construction for deep foundations. EA Piling offers rotary piles of up to 1200mm in diameter and over 30m in depth.
Advantages: high loads, minimal settlement, low vibration, larger depths and diameters achievable than with CFA piles
Applications: load bearing piles, contiguous walls, secant walls.
Process: An auger and bucket is bored into the ground over its length and then withdrawn to remove the spoil. Temporary casings or bentonite fluid are used if the soils require lateral support to remain open. Once the design depth is reached, a full-length reinforcement cage is inserted into the hole. Finally, concrete is poured to fill the hole and form the pile.
Driven Piles
Driven piling is a versatile and economical technique to install either precast concrete or steel section piles. It is suitable for a wide range of soils where noise and vibration are not restricted. EA Piling can install driven piles using a vibro-hammer or an impact hammer.
Advantages: no spoil, rapid installation, particularly suited to soft soils with high water tables, a large range of depths and diameters are possible.
Applications: load bearing piles, marine structures, bridge abutments.
Process: Either an impact or vibration hammer is used to drive the pile to the required depth within the soil. The hammer can be slung from a crane or attached to a purpose made leader piling rig. Prior to driving, a guidance frame is erected to ensure the correct positioning and verticality of the piles.
Sheet Piles
Sheet piles are a versatile product which can be used to support both permanent and temporary excavations. Thanks to their interlocking joints, sheet piles can form water-tight walls for cofferdams. EA Piling has capacity to import both Z- and U-section sheet piles from our partners in Europe.
Advantages: water-tight, can be re-used, quick to install, versatile, lightweight, low-maintenance.
Applications: cofferdams, marine structures, quay walls, basement excavations, retaining walls.
Process: Steel sheet piles are installed into the ground to the required depth by using either a vibrating hammer or an impact hammer. Subsequent sheet piles interlock to form a continuous wall. The driving hammer can be slung from a crane, attached to an excavator or form part of a leader piling rig.
Contiguous Retaining Walls
Contiguous retaining walls are made of bored concrete piles with a gap of approximately150mm between each pile. This form of retaining wall is most suited to soils where the groundwater table is below the final level of excavation. When working in cantilever, contiguous walls can typically retain up to 7m of earth. External steel bracing or soil anchors may be installed to provide additional lateral support for deeper excavations.
Advantages: quick, cost-effective, efficient, CFA may be used.
Applications: retaining walls, basement excavations, slope stabilisation.
Process: Contiguous piles are installed using either CFA or rotary bored techniques with a 150mm gap between each pile. The soil between each pile can be stabilised with grout if necessary.
Secant Retaining Walls
A secant pile wall comprises a series of overlapping concrete piles to form an earth and water retaining structure. Secant walls are installed using the rotary bored piling method. Typically, an unbraced secant wall can retain between 5m and 7m, depending on the stratigraphy of the site. External steel bracing or soil anchors may be installed to provide additional lateral support.
Advantages: can be formed in waterlogged soils, high lateral load capacity, minimal lateral deformations, less vibration from installation than sheet piling.
Applications: retaining walls, basement excavations, slope stabilisation, water-tight cofferdams
Process: A secant wall consists of both reinforced and unreinforced concrete piles. The unreinforced “soft” piles are installed first using a weaker grade of concrete. Then the reinforced “hard” piles are installed which may contain either a reinforcing cage or a steel beam.
Soil Nails
Soil nails are typically used for stabilising earthworks including excavations and slopes prone to slips. They consist of steel bars drilled and grouted deep into the stable soils behind the face of the slope or excavation and a protective facing added to the slope.
Advantages: Cost-effective, enables deep excavations in excess of 10m, can be installed in areas with restricted access, does not require external bracing.
Applications: Slope stabilisation, reinforcing against landslides, facilitating unnaturally steel excavations.
Process: Holes are drilled into the wall face to a depth specified by the design. Tensile steel members are then inserted and grouted into place.
Nails may be post-tensioned to further strengthen the retained soil. A bearing plate is attached to the heads of the nails to ensure good bearing against the slope surface.
Ground Anchors
Ground anchors are used for tying back or anchoring structures that may otherwise be unstable. They are most commonly used for lateral support of retaining walls such as those used in deep basement structures.
Similar to soil nails, they consist of steel tie bars or strands drilled and grouted into stable soils, in this case behind the supported structure.
Advantages: Cost-effective, reduces required size of retaining walls, high tensile capacity.
Applications: Lateral support of retaining walls, locking tension structures, stabilising existing unsafe structures.
Process: Anchors are installed after the construction of the structure they are to support. The installation process is the same as that for soil nails.
Pile Integrity Testing
EA Piling undertakes integrity tests on the majority of our piling projects. TDR2 integrity tests are undertaken by a certain sonic wave being generated at the top of the pile. A highly sensitive specialist microphone detects sonic waves reflected by any potential defects in the pile concrete.
Integrity tests are used to check for structural integrity in a pile. Our test data is independently analysed by a laboratory in the UK to ensure utmost reliability.
Pile Load Testing
Many of EA Piling’s projects require various tests to verify both the design assumptions and construction quality. We provide all testing required by our clients in order to give full assurance of our work.
Static Load Testing: Static load testing involves incrementally loading a pile in the vertical direction to approximately 150% of the pile’s design load. This is done using a system of hydraulic jacks and load cells. During loading, the displacement of the pile head is measured by dial gauges to record how far the pile moves over the load sequence.
This test is used to verify the properties of the soil assumed in design. EA Piling can undertake static load testing by Kentledge (Weightbox) and Reaction Pile methods for both tensile and compression tests.
Lateral Load Testing: Lateral load tests use a hydraulic jack to apply load to the side of a pile. The horizontal displacement of the pile is measured during loading.
The test is used to measure a pile’s response to horizontal loading, and is particularly useful for retaining structures, anchor piles, and to check for seismic stability.