|
|
Keller's Augercast Continuous Flight Auger (CFA) piling system provides a quiet low vibration form of piling that is ideal for providing foundation support in built-up or environmentally sensitive areas.
Keller's CFA rigs can construct piles in most soils including sands, gravels, silts, clays, chalk and weak bedrock, in high water tables without the need for temporary support systems.
|
|
|
|
|
|
Keller Ground Engineering offers a range of high capacity small diameter drilled and bored pile systems purposely designed to tackle difficult ground conditions and working in limited space and low headrooms.
Highly versatile, compact but powerful rigs, can install piles in virtually any location whilst being able to tackle drilling through different soils, obstructions and forming substantial rock sockets.
Keller's drilled Minipiles are available in diameters of up to 350mm and in appropriate soil conditions can provide safe working loads in excess of 1000kN. Widely used for refurbishment of buildings, Minipiles are utilised for upgrading of existing foundations by stitch drilling or underpinning and for the provision of retention schemes, i.e. basement walls within limited access and headroom. Keller Minipiles are also used extensively in the infrastructure sector for forming earth retention systems to support unstable embankments and cuttings etc. and strengthening of existing foundations.
The Keller Minipile system operates with very low levels of noise or vibration and is highly suited to built up urban environments. Piles can be constructed in headroom as low as 2.1 metres.
The pile shafts are constructed from cement-based grouts with cage, bar or other reinforcement appropriate to the application.
|
|
This type of deep foundation is currently by far the most widely used in the world.
SEFI-INTRAFOR produces several types of piles.
None of them provides a universal solution, but each type is designed to meet specific requirements.
|
|
|
|
|
|
TRELICON technology joins the advantages of fixed piles with the versatility of application of drilled piles. A perfect method for projects in urban centres, as it eliminates vibration and disturbance to adjacent structures and reduces noise emissions. TRELICON piles make it possible to avoid decompressing the soil and using bentonite mud for drilling. This greatly simplifies the disposal of debris. Thanks to its constant technical improvement, this technology has significantly broadened its fields of application, allowing for a much wider range of diameters and lengths.
Operating specifications
The operating phases entail digging the pile by driving a continuous blade assembled on a central hollow pipe. At the end of the digging phases, extraction of the blade occurs at the same time concrete is poured by pumping from inside the same blade. When required, piles may be reinforced for their entire length with reinforcement cages inserted in the still wet concrete.
Technical data
Pile diameter: 400 to 1400 mm
Depth: 25 ÷ 36 meters (with blade loader) depending on soil diameter and consistency.
|
|
Covered in the New Spanish Technical Code for Building (CTE-2006) as rotation displacement piles, the Omega pile driving system is based on rotation and pushing the head of the displacement auger when driving it and rotating and pulling the tool when extracting it. Piles are installed in a total absence of vibration and produce sideways displacement of the soil, thereby compacting it and avoiding the need to remove debris.
Above the maximum diameter of the head, horizontal propellers and suitable tilt of the upper angle produce a second displacement of the soil during the extraction process and concreting. In this stage, the controlled pressure of the concrete injected through the centre pipe induces a third displacement and ensures perfect adherence of the pile with the ground.
|
|
|
|
|
|
The MP/50 MINI PILES, or the steel-cement tubes, are noiselessly pressure driven through the holes. There is no need to remove any soil and special anchors fixed to the structure are used to secure the hydraulic jack.
These elements are installed in sequence and secured together using a pressed coupling. The hydraulic jack is equipped with a gauge, which indicates the pressure required to drive the steel-cement piles into the soil. Therefore, the load of each mini pile is tested individually. When the mini pile reaches a stratigraphic formation which allows it to resist the desired drive force (which can vary from a minimum of 8,000 kg to a maximum 12,000 kg) the jack is removed and the MP/50 MINI PILE is internally and finally cemented into the foundation. Considering the reduced dimensions of the mini piles, the holes do not weaken the foundation and the foundation does not need to be reinforced in terms of dimensions and structural rigidity. The mini piles are easy to install using machines requiring little clearance, which can also access cellars and confined spaces in general.
|
|
Concrete industrial floors often present serious sinking problems.
In most cases, the floor sinks because the foundation has not been carried out properly or because there are deeper layers of soil with poor consistency. The resin-mini pile method is the perfect solution for these issues. Injecting the foamed resins below the floor fills any cavities that have formed, compresses the soil below and raises the floor by as much as 20-30 centimetres until it is perfectly level. By subsequently applying the pressure driven mini piles, the weight is transferred below the soil avoiding any future sinking.
|
|
|
|
|
|
This technology can be applied to:
New buildings, swimming pools, silo bases, concrete beds for any type of structure.
It is common for buildings or constructions on concrete bed foundations to sink in different areas. The buildings tend to remain intact but rotate and tilt to one side or slant on one corner.
During its over ten years’ experience, Novatek has treated and resolved countless similar cases, raising the structure using foamed resins and then securing it into place with micro piles.
To prevent a building or structure built on concrete bed foundations from developing this problem, it is possible to act in advance during the construction phase by using the simple and economic PX780 pressure driven micro piles.
It is necessary to insert jackets alloyed to the reinforcement in the concrete bed. After the concrete has been cast and partially cured, the PX/80 micro piles are driven into the concrete.
The design engineer and calculator will provide indications regarding the degree of weight to offload underground, which could correspond to the weight of the entire building or it could be calculated to guarantee an even and balanced load distribution.
PX/80 micro piles are pressure driven into the ground by a hydraulic jack equipped with a gauge to individually test and certify the necessary driving pressure and the effective load bearing capacity of each micro pile.
|
|
|
|
|
|
Micropiles allow solving some problems concerning the execution of foundations thanks to the possibility of using equipment having reduced sizes and encumbrance, and to the minimum disturbance caused to the soil and pre-existing structures.
MICROTREVI I is particularly suitable for being executed in soils that can be drilled by means of the rotation technique. In these cases, the same steel pipe making up the reinforcement of the micropile is used as drill string during the boring phase. To this aim, its bottom side is provided with a sacrificial three blades bit (drag bit). Close to the bonded length, the pipe is equipped with special non-return valves, "VELANOR" type, that are housed within the pipe thickness so that they are not damaged during the drilling phase. Said valves allow - whenever requested - to re-grout the micropile in a following time.
MICROTREVI II doesn't require the formation of a cement sheath for its execution, since the shaft of the micropile is plitted by means of bag packer. The single sections between bag and bag are subsequently pressure grouted. Said method assures an improved control over the grouting pressure and it allows grouting into those formations which would require excessive pressures due to the failure of the sheath, with following claquage risks.
|
|
Micro-piles enable the implementation of foundations for new structures or
the reinforcement of old structures in confined spaces.
This method consists of transferring the loads from the structure to the soil by sinking a small pile (diameter under 250 mm) generally fitted with a metal insert (ribbed blocking bar, tube).
Micro-piles can be used for working in compression, traction or a combination of both.
|
|
erratest has the technical capacity and know-how to install micro-piles using its highly-qualified personnel to offer the best solution and to execute the project once that solution has been decided upon.
Terratest has the most up-to-date equipment thanks to its ambitious yearly programs of capital investment, which enables us to remain permanently at the forefront of quality and productivity.
Some of the applications where Terratest develops its micro-pile technology are:
* Underpinning
* Foundation strengthening for building extensions
* Strengthening of existing foundations for basement excavation
* Deep foundations in soils not apt for conventional piles
* Umbrellas for tunnel mouths
|
|
Rotation with recoverable steel casing
In all types of ground (exept large boulder or blocks)
Minimum concrete consumption,most usual diameters :650-2200mm
|
|
|
|
|
|
The pressure driven mini piles mean it is much easier, practical and faster to increase the load bearing capacity of industrial floors or existing foundations for the installation of heavy or precision machinery, the construction of indoor metallic infrastructures, the installation of automated warehouses, overhead travelling cranes and mezzanines.
Generally, in all these cases, suitable foundations have to be installed (consisting in adequately sized plinths).
To do this, it is necessary to break up the existing floor, remove earth, install reinforcements and cast concrete.
These are invasive procedures and are not always easy to carry out within an existing structure. By simply installing pressure driven mini piles, Novatek is able to increase the load bearing capacity of a normal industrial floor so that it is able to support the new required loads. Machinery weighing hundreds of tonnes no longer requires a huge base which takes a long time to create and is highly invasive. All you need to do is install a series of mini piles whose layout and capacity is designed and calculated according to your specific requirements. The absolute reliability and safety of the process is guaranteed by the fact that the effective load bearing capacity of the mini piles is individually tested and certified.
|
|
Prefabricated Concrete Micropiles are reinforced centrifugated concrete pipes for special foundations. The friction between pile and surrounding land is assured by the lateral high pressure injections of cement (without packer).
The installation is like normal micropiles. In few minutes a simple machine can put the pile in the hole, and a workman completing all the injections.
Usual diameter : 210 mm
The most important advantages are :
- velocity of the work
- reduced cost
- high load capacity
- best protections about pitting
|
|
|
|
|
|
Typical reinforcement is 8 pre-tensioned steel strands of 0.5” section as longitudinal reinforcement and transverse reinforcement made up of rings of 6 to 10 cm. diameter at the ends of the pile.
Pre-tensioned, pre-fabricated piles are especially suitable for installation in very soft soils where significant tensile stress may be exerted during pile driving.
Applications:
Structures (bridges and viaducts)
Multi-storey buildings or edifices in seismic areas where foundations are subjected to significant buckling stress.
Structures and buildings where the lowest elevation is below the water table, so that the piles are subjected to tensile stress due to under-pressure.
Retention of earthwork embankments, basements, etc., (pile wall).
Industrial buildings with significant horizontal or buckling stress.
As for Prefabricated Reinforced Piles, the quality of these Pre-tensioned Pre-fabricated piles is monitored both at the factory and on the building site (PDA, static and dynamic load testing, vibration control).
|
|
Prefabricated Concrete Piles are reinforced concrete pipes for special foundations of Bridges. The friction between pile and surrounding land is assured by the lateral high pressure injections of cement (without packer). Structural resistence is assured by a tickness of 10-15 cm of high quality reinforced concrete.
The installation is like Drilled Piles. Then in few minutes a simple crane can put the pile in the hole, and a workman completing all the injections.
The most important advantages are :
- veolcity of the work
- reduced cost
- high load capacity
- best protections about pitting
|
|
|
They are driven piles in which the pile is formed by prefab elements, with a square or round section. They can be jointed or made of a single element. Piles with a square section ranging from 400 to 600 mm work at 150 and 200 tons, respectively. A good sections' alignment is required in order to avoid cutting stresses during re-driving operations.
|
|
TERRA pre-fabricated piles are capable of handling vertical compression stresses of around 12.5 N/mm2 (NTE, CPP-78) or 0.3 * fck (Technical Building Code, Basic Document SE-C, 2006), as they are Category 1 piles that are prefabricated under strict control in permanent installations.
In all cases they are made of concrete with minimum resistance properties of 45 N/mm2.
Likewise, I 52,5 N/SR (RC-03) cement is always used, which makes the piles resistant to sulphates and seawater.
Both the manufacture and on-site driving of our piles are separately guaranteed by AENOR Quality Assurance certification (UNE-EN ISO standards 9001:2000 and UNE-EN ISO standard 9002:1994).
TERRA prefabricated piles are systematically monitored during their manufacture (raw material reception, resistance and geometry, manufacture, concrete resistance and consistency) both at the factory and on the building site (static and dynamic load testing, integrity trials...l).
|
|
|
Bored Piles are circular piles made of concrete and steel being installed in the soil by various drilling methods. They divert high structural loads into deeper, stronger soils, form stringed together a retaining wall for excavation pits or terraces remove obstacles in the soil or block ground water below the surface. Depending on the application length, diameter, material, formation, and placing of the individual piles can be adapted.
|
|
Drilled piles are often used in 'critical ground' where there is a risk of subsidence. A drilled pile is also used when noise pollution has to be avoided. In addition a drilled pile is used to 'drill out' another pile. Advantage: vibration free and fully ground penetrating. Disadvantage: the costs of drilled piles are higher than those of prefab piles.
Drilled piles were used in the construction of the Goes council offices. The ground turned out to be rock hard because of the fine soil layers containing shells, silt and very fine sand. Because of the central location in the town of Goes drilled piles had to be used for the foundations in order to keep the nuisance to a minimum.
|
|
|
Some very heavy structures (high rise towers, industrial buildings) need foundation piles which can each bear a load of several thousand tonnes. The solution lies in increasing the cross sectional area of the foundation, using multiform piles or circular piles up to 3 metres in diameter. If the ground does not display sufficient strength, the piles may be belled out (under-reamed) at the bottom.
|
|
|
The Continuous Flight Auger (CFA) system is well known as a rapid and cost effective open site method of constructing load bearing and retaining structure piles where the appropriate ground conditions exist. This makes it suited to many construction projects and particularly for sensitive sites, where it provides a quiet and vibration free piling technique.
|
|
Micro piles are foundation elements up to a diameter of 300 mm, being able to transfer loads through skin friction into deeper, competent soil stratums.
The special feature about micro piles is a.o. that a high bearing capacity is possible due to well-targeted injection techniques with small diameters.
A great variety of rigs and equipment enable highly productive methods to install mini piles even at limited working space.
Buildings damaged by erratic settlements can be stabilised and/or lifted by prestressable mini piles.
|
|
|
Micropiles are small diameter drilled and grouted friction piles. Each pile includes steel elements that are bonded into the bearing soil or rock - usually with cement grout. The bearing stratum is logged during installation drilling to assure that bearing capacity is adequate. Micropiles do not rely on end-bearing capacity, so there is no need to establish the competency of rock beyond bond-depth. They can be installed quickly in virtually every type of ground using highly adaptable mobile drilling equipment. These steel piles have working capacities up to 250 tons.
|
|
|
This nomenclature refers to piles of small section and low to medium load capacity. The basic principle is to install these piles with small, light and manageable equipment, and to use them wherever conventional equipment is unable to operate; underpinning, strengthening, bracing, take-up of bending and tensile loads due to fill, resistance to negative friction, etc.
|
|
A vibro combi-pile is a ground penetrating concrete pile with a grout casing. The basis of this principal is the same as that of vibro-piles. However, no reinforcement is hung inside or concrete cast.
With a vibro comb-pile a prefab core is set in the steel tube and the open space is filled with grout. This creates a pile that can resist large tensile forces and is primarily used to anchor underwater concrete floors. Vibro combi-piles were constructed on the HSL Roelofarendsveen track.
|
|
Concrete piles can bear greater loads than wooden piles. The prefab concrete pile is a traditional type of pile: ground penetrating and suitable for both small and large structures. Price-wise prefab concrete piles are an attractive option and because of the pre-tensioned reinforcement they can be supplied in various diameters.
The length of a prefab concrete pile runs to a maximum of 38 metres (longer is not practicable due to transport considerations and their susceptibility to breakage). A short note: the pile is smooth therefore it cannot 'bite into' the ground. More and more often prefab concrete piles are installed using hydraulic pile drivers.
Ballast Nedam Funderingstechnieken installed prefab concrete piles, amongst others, at the Kortsluitroute on the south side of Rotterdam. And prefab concrete piles were also used in the construction of the track for the HSL at Zwijndrecht.
|
|
|
The BAUER Ductile Pile is a fast, simple and highly effective foundation system. For the purpose of load transfer ductile cast iron tubes are driven into the ground with high frequency hydraulic hammers. This system can support loads from all kinds of superstructures.
|
|
An MV-pile is a steel profile that is driven into the ground with a grout injection. The grout ensures that the pile 'cements itself tight' into the ground after which, for example, they can be attached to a combi-wall so that the full wall can absorb the tensile force. During driving a hollow space is created above the foot of the MV-pile which is injected from below with cement mortar, fine concrete or other self-hardening materials (during driving) using a high pressure lance.
MV-piles serve as anchors in both the horizontal and vertical directions. For horizontal anchoring the piles are driven into the ground at an angle and this way function as compression or traction elements. They are often used for quay walls. As vertical anchoring they are used as an alternative to vibro combi-piles.
|
|
|
|
