GB2519542A

GB2519542A - A jacking device

Info

Publication number: GB2519542A
Application number: GB1318754.7A
Authority: GB
Inventors: Simon Paul Collis
Original assignee: GEOINNOVATIONS Ltd
Current assignee: GEOINNOVATIONS Ltd
Priority date: 2013-10-23
Filing date: 2013-10-23
Publication date: 2015-04-29
Anticipated expiration: 2033-10-23
Also published as: GB2519542B; GB201318754D0

Abstract

A jacking device for use in movement of a load 170 such as a foundation; in particular for moving a load that has become displaced to an undesirable position and therefore requires correction for example to lift sunken flooring due to settlement. The jacking device 120 is engaged with the load and may be embedded and fixed within the load. The load is moved by use of a displaceable member 140 acting upon a pile 100 so as to displace the load. A resultant void 300 created due to movement of the load may be backfilled with a setting agent so as to stabilise the load in the second position. The device may be bonded to the load by adhesive in a cavity between the load and the device. There may be a sensor provided to monitor movement of the load in relation to a datum. There is also a closure plate for covering an end of the device.

Description

A JACKING DEVICE

Field of the Invention

The present invention relates to a jacking device, in particular but not exclusively a jacking device for altering the level of a slab or foundation.

Background

There are a number of situations in construction where large loads need to be moved such as flooring or foundations, for example where slabs or foundations have subsided.

Typically this process of moving loads such as flooring or foundations is carried out by an injection method or complicated mechanical assemblies that cause movement of the load.

In such situations the ground below the flooring may be accessed and a selling fluid added so as to attempt to correct the settlement and lift the flooring that has sunk. However, in some situation such a method may not be possible or effective.

Floor jacking is a method of enabling a floor to be moved in order to correct the level of floors or foundations that may have sunken or are damaged.

Therefore altering the floor level and/or stability is a technique which can be used to rectify these problems. A jacking system typically serves to lift the floor with great accuracy.

Prior Art

US 6 929 249 (Simons) refers to a pneumatic lift device capable of elevating a load by a lift unit wherein the lift unit comprises a platform and a base between which an expandable bladder is provided that accepts an air supply so as to allow a platform to be lifted from a base in order to displace a load.

US 6 814 525 refers to a bracket placed under a slab and moved upward by adjusting a moving bracket centred on a screw thread mounted on a tubular pile. The bracket is inserted through a slot and rotated to achieve a bearing in an excavated cavity below the slab.

US 5 205 673 discloses an apparatus and method for supporting and lifting building foundation slabs utilizing an above-slab, power cylinder activated, lift assembly and a below-slab support bracket. The bracket is an elongated plate which is inserted through a small access slot cut in the slab and then rotated to extend transversely of the slot. Lift rods are connected between the bracket and a cross arm of the lift assembly positioned above the slab.

The cross arm and the bracket include aperture guides for slidably receiving and guiding pilings successively driven under the slab by power cylinders connected from the cross arm.

US 20080236061 Al reveals a floor slab support system for jacking and stabilizing a sagging or cracked floor or other such slab. Holes of 3%" diameter, for example, are drilled through the slab and a pipe pier driven downwardly until reaching bottom. A connector sleeve matching the slab hole size is temporarily suspended in the slab hole and a L-shaped brackets are inserted into the sleeve and manoeuvred to extend outwardly through slots in the sleeve to engage the underside of the slab.

A threaded rod with a threaded positioning member and a bottom stop is inserted through the sleeve and into the pipe pier, and the L-shaped brackets extended through the sleeve and maintained outwardly by the threaded positioning member. Once in position, the threaded rod is rotated to screw the * sleeve and brackets upwardly to support the slab. Finally, the top of the rod is cut off and the hole filled with concrete.

Reference is also made to our co-pending UK Patent Application GB 1213003.5 which describes a system for soil consolidation comprising: a structural delivery channel that is closed at one end and adapted to receive a grout or resin through an open end, the channel has a plurality of apertures that are selectively openable and closable in order to permit, in use, the grout or resin to egress from the channel into selected regions of surrounding soil at desired times. The device allows the accurate placement of grout into soil to form a solid permeation grouted mass around the delivery channel permitting loads to be placed upon the structural delivery channel. The composite nature of the permeation grouted mass and structural delivery channel, which comprises a substantial tube, is to form a composite pile.

An object of the invention is therefore to overcome problems associated with the aforementioned systems.

Summary of the Invention

According to a first aspect of the present invention there is provided a jacking device accepted in an aperture formed through a load the device is adapted to engage with the load and sit atop a pile, whereby in use, the device, when engaged with the load, in use, is adapted to be displaced relative to the pile.

The load may comprise any object to be moved such as a slab, floor or foundation.

In preferred embodiments the jacking device is engaged with the load so as to be fixed in position. The jacking device and load may engaged by a bonded interference fit such as by use of adhesive.

In this way the jacking device or device can be used to move the load in relation to the pile. Typically this will be to correct the level of subsided or sunken slabs or foundations.

In preferred embodiments the jacking device is arranged in the load wherein the jacking device is fixed within the load in use, so as to remain absolutely static within the load.

In preferred embodiments the device is a substantially tubular member having an outer diameter of at least 70mm and preferably at least 72mm, an inner diameter of at least 60mm and preferably at least 65mm wherein the device thickness is at least 2mm, preferably at least 5mm and ideally at least 10mm.

Therefore the jacking device can be readily installed with minimal disruption using small light equipment.

Typically the jacking device is adapted to apply a force of at least 100 kN and it is ideally capable of applying much greater forces.

Preferably the device may be inserted into the aperture created in the load for receiving the device. Ideally the aperture is dimensioned to receive the device wherein the device fits snugly within the aperture but is capable of being readily inserted to the aperture without application of force. Ideally the aperture is also dimensioned so as to have a wall that is substantially parallel to an outer surface of the device. In this way movement of the device in the aperture is limited.

In preferred embodiments the jacking device is cylindrical and is fitted into a round aperture unmodified with slots. There is no requirement for slots to be provided or for excavation beneath the load for the placement of brackets as the jacking device(s) is/are fitted in, and fixed to, the load in situ.

Typically the device is attached the load for example the slab or foundation by a strong adhesive. Such a method of fixing the jacking device to the load is reliable, quick, inexpensive and permanent. Therefore the jacking device remains in-situ and can be reactivated for further use at a different time if required.

In some embodiments the aperture wall may be contoured for example being rifled, keyed or including notches that may aid with adhesion of the aperture wall to the device. In some further embodiments the contours may correspond to the device so that the aperture and device interlock.

Typically the aperture may be drilled into the load which is to be moved, for example apertures may be drilled into a foundation for a building, and the device(s) then inserted into the aperture(s).

Ideally the device may be fixed in the aperture so as to prevent dislodgment in use. Preferably the device is capable of receiving a coating layer intermediate the device and the load that serves to fix the device within the aperture.

Preferably the coating layer is an adhesive arranged between the device and load. Typically the adhesive may be a quick setting, strong, durable, water resistant adhesive such as epoxy resin, solid polyurethane or high strength cementitious grout.

Preferably the device has an 0-ring provided around an outer circumference of the device. Ideally the 0-ring is dimensioned to contact the load in use and define a cavity surrounding the device into which the adhesive layer can be added. In use the 0-ring serves to prevent the escape of the adhesive layer from the cavity and therefore prevent escape of adhesive fluid beyond the device's footprint.

Ideally the 0-ring may be arranged partially in a recess around the outer circumference.

In a preferred embodiment the 0-ring may be located distally on the device so as to provide a larger cavity into which the coating layer can be added along the length of the device thereby forming a stronger connection between the device and load by providing a greater surface area for attachment.

Typically the 0-ring may be resiliently deformable so as be capable of deformation whilst being inserted into the aperture whilst also maintaining contact with the aperture. For example the 0-ring may be formed from rubber or silicone.

In preferred embodiments the device includes a textured outer surface. The outer surface may include raised and lowered portions so as to improve purchase for the adhesive. For example the outer surface may be contoured, keyed, knobbled, ribbed or knurled. In this way the device is fixed more securely within the aperture by the adhesive so as to be capable of bearing greater loads.

The aperture typically traverses the load that is to be moved so as to allow insertion of the pile through the aperture and therefore through the load to the ground below in which the pile will be embedded.

Ideally the device length is dimensioned to be no greater than the thickness of the load to be moved, thereby only serving to provide movement of the load and not other surrounding layers or structures.

Preferably the device is dimensioned to fit about the pile wherein the device is free to move about the pile in use. Preferably the device has an inner circumference that is at least equal to and preferably larger than the pile's circumference so as to allow the device to be readily positioned and moved about the pile whilst remaining substantially parallel in relation to the pile.

Typically the device is formed for a strong, durable material such as metal or metal alloy so as to be capable of lead bearing and suitable for use in the ground and to remain in situ and intact indefinitely.

Ideally the device is formed from steel.

In preferred embodiments the device includes an end cap. The end cap serves to partially close the device, only allowing access for the displaceable member. For example the end cap may be in the form a ring that is inserted into the device thereby providing an opening through which the displaceable member may be accepted.

Preferably the end cap may be threaded so as to be screwed into the device.

In this way the end cap can be readily removed, for example whilst inserting the pile but may be selectively closed in order to receive the displaceable member.

In some embodiments the end cap may be integral with the device.

In preferred embodiments a method of displacing the load with respect to the pile is provided comprising the steps of: filling a jacking device in an aperture formed in the load, inserting the pile and displacing the device, with respect to the pile, thereby displacing the load.

In preferred embodiments the device is used together with the pile so as to enable movement of the load. Typically the device in use is arranged about the pile, wherein the pile is inserted to the ground, through the device.

Preferably the device is inserted and fixed into the load prior to the pile being driven into the structure beyond the load. For example the device may be fixed in the aperture and once the adhesive is set the pile may be driven into the ground below the foundation. Advantageously in this way there is no requirement to attempt to insert the device about the pile and within the aperture after the pile has been inserted which may be problematic if the pile is slightly misaligned, for example due to obstacles encountered whilst driving in the pile.

In some embodiments where it may be necessary to insert the pile prior to insertion of the device a centring tool may be provided to ensure the pile is correctly aligned.

Typically the centring tool is a cylinder dimensioned to fit within the aperture wherein the centring tool includes an annular shoulder that serves to locate the tool at the aperture entrance. The shoulder is dimensioned to be larger than the aperture so as to prevent the tool dropping through the aperture and securing it at the aperture opening.

Ideally the tool protrudes at least 50mm from the aperture. It may be envisaged that the shoulder may be located 50mm from a proximal end. In this way the portion of the tool outside of the aperture is sufficiently strong to withstand associated forces whilst driving the pile into the ground.

Alternatively the shoulder may be at least 50mm for superior strength.

Typically once the pile has been located through the device a ram plate may be positioned on a proximate end of the pile. The ram plate is provided for receiving the displaceable member. Ideally the ram plate abuts the displaceable member in use. The ram plate is typically formed from a strong and durable material such as steel, capable of bearing point loads so as to direct force through the pile.

In some preferred embodiments the ram plate may include a recess for accepting the displaceable member, in this way the member is located to prevent slipping in use and furthermore may be used to centralise the member to ensure even and accurate movement of the load with force directed through the centre of the pile.

B

In same embodiments more than one ram plate may be used, for example a first ram plate mounted on the pile and a second ram plate including a recess positioned atop the first ram plate. A railer bearing or grease may be applied between these plates to reduce friction in a thread operated displaceable member.

Ideally the displaceable member is accepted through the end cap arranged at the proximate end of the device. Therefore the displaceable member serves to fully close one end of the device.

In this way with the member abutting the ram plate atop the pile the displaceable member is positioned upon a fixed object -the pile. Therefore as the displaceable member is forced through the device via the end cap the displaceable member is blocked by the pile and therefore the device and associated load is displaced in respect of the pile.

In a preferred embodiment the displaceable member is threaded. Accordingly the end cap includes a threaded opening so as to accept the threaded displaceable member. In this way as the displaceable member is turned the length of displaceable member inserted within the device is altered. As the tip abuts the ram plate atop the pile the member is blocked and the device and thereby the load are displaced.

Ideally the displaceable member may include a drive head so that the displaceable member can be readily turned and if required, mechanically driven. For example the drive head may be in the form of an hexagonal nut for means for mechanically driving the drive head.

In some embodiments a torque wrench can be used to measure the lifting force applied against the pile.

Advantageously, when using the threaded member to adjust the load exact displacement of the load can be measured against the threaded member.

In other embodiments the displaceable member may operate by hydraulic means so as to reduce friction. Preferably a hydraulic assembly including a piston may be provided instead of, or in addition to the ram plate, being located in use upon the pile.

Typically the hydraulic assembly is dimensioned to be received by the device wherein the piston serves as the ram plate, or one of the ram plates. Ideally the piston is formed from solid steel or steel alloy bar.

Preferably the piston includes at least one and preferably two outwardly mounted 0-rings that abut with the device inner wall and serve to prevent hydraulic fluid added to the hydraulic assembly from leaking out of the space defined by the 0-rings, for example leaking to the area around the pile. The device thereby functions as pad of the hydraulic assembly by housing the piston and providing a conduit into which hydraulic fluid may be added.

In use the end cap serves to close the device and therefore providing a seal area in which hydraulic fluid can be added. Ideally the end cap includes a nipple through which hydraulic fluid such as grease can be inserted to as to engage the piston wherein addition of fluid to the piston causes movement of the load.

In some embodiments a means may be provided to measure pressure within the within the hydraulic assembly to indicate the force applied against the pile.

For example the hydraulic assembly may include a pressure gauge or alternatively amount of hydraulic fluid added to the hydraulic assembly is measured. In this way exact displacement of the load can be measured.

Advantageously the end cap is interchangeable with the earlier mentioned end cap with the threaded opening. In this way the method of jacking can be altered or varied depending upon the situation, for example in response to accessibility or load to be lifted.

In another embodiment and according to a second feature of the displaceable member the jacking device is adapted to engage with the pile and support the load, whereby in use, the device receives a displaceable member for displacing the load with respect to the pile. For example the displaceable member may include a planar member fixed part way along that is arranged below the load to be moved in use. In this way the planar member is moveable with the displaceable member and therefore may be arranged to move the load when the planar member is in contact with the load and being driven.

Ideally the proximate end of the pile is located in use so as to finish at floor level and preferably just below floor level. In this way the pile is able to accept the device so that the device is also located in the floor in use.

In preferred embodiments a permeation pile is used. In this way the pile diameter is typically less than standard piles and therefore the required aperture in the load is less and therefore the disruption caused during operation is reduced.

Preferably the jacking device is used with the permeation pile as described in our co-pending UK Patent Application GB 1213003.5. The permeation pile is used so as to provide a structural support below ground upon which the jacking device is supported.

Typically the device is sacrificial so as to be left in situ after use and advantageously enabling future use if required.

In a preferred embodiment the device may be provided with a closing cap so as to conceal the device in the load whilst not in use.

In preferred embodiments the jacking device may be used as part of a load jacking system wherein a plurality of jacking devices are arranged in the load so that the relative position of the load at one jacking device can be assessed in relation to another at a different location in the load thereby enabling levelling of the load.

Typically the displaceable member may be operated by the driver or driving means so as to displace one or more jacking devices at any one time with respect to the piles.

It may be envisaged that the system may include a controller so as to remotely engage the driving means and thereby movement of the load incrementally. In this way adjustment of one or more of the piles separately or.

in unison can be achieved so as to enable levelling of the load.

In some embodiments the system and in preferred embodiments the device may include a level sensor so as to indicate movement of the device in use.

Typically engagement of the driving means may be in response to the information rebeived from the level sensors.

In some embodiments a datum may be provided to indicate the present position of the load wherein movement of the device in relation to the datum is detected by the level sensor so as to monitor movement of the load during operation of the system. In this way the amount of movement can be determined and recorded thereby enabling exact incremental adjustments to be made.

It may be envisaged that the datum may be separate to the device or integrated with the device. Typically the level sensor is capable of communication with the datum so as to monitor movement.

Accordingly movement of the load may result in creation of a void, for example in the gap between the first position of the load and the final position of the load. Preferably this void is back-filled so that the load cannot return to the first position. For example the void may be pumped full of a setting agent such as cement grout, concrete or structural chemical grout.

Brief Description of Figures

Figure la shows an overall diagrammatic view of a building on a sunken foundation; Figure lb shows a building on a foundation that has been raised by load jacking after deployment of the invention; Figure 2 is a cross sectional view of an embodiment of a jacking device positioned in a load; Figure 3 shows a cross sectional view of the jacking device, of Figure 2, with a drive head for driving the displaceable member; Figure 4 is an overall view of a load jacking system; Figures 5a to 5c show an overall view of a load management system incorporating the present invention and progressive stages of movement of the load by the system; Figure 6 shows a jacking assembly with two ram plates; Figure 7 shows a centring tool for centrally locating a pile within an aperture; and Figure 8 shows a hydraulic assembly for moving a load.

Detailed Description of Preferred Embodiments

Referring to the Figures, Figure la shows an overall view of a load 170, in this example a foundation 170, located below a building 200 that has become sunken, for example due to settlement or subsidence so as to alter the level of the flooring.

Figure lb shows the corrected foundation 170 that has been moved from the sunken position to a raised position by use of the load jacking system so as to level the foundation 170 upon which the building 200 is arranged. Therefore correcting the load, in this case a floor above a foundation, to its original arrangement.

The action of moving the foundation 170 has revealed a void 300 below the foundation 170. The void 300 is backfilled typically with a liquid filler such as concrete or resin thereby preventing the foundation 170 from returning to its sunken position and thereby maintaining the foundation 170 at the corrected position.

Figure 2 reveals the jacking device 120 situate in an aperture 180 wherein the jacking device 120 is fixed in the aperture 180 by means of adhesive 130 so as to secure the jacking device in positioning.

The aperture 180 is round so as to accept a tubular jacking device 120. The aperture 180 shown is of near equal depth to that of the foundation 170 wherein the device 120 is the same depth. Therefore the aperture 180 and device 120 traverse the foundation 170 so as to provide purchase through the foundation 170. In this way the device 120 can be best secured within the aperture 180 by the adhesive 130.

The device 120 has a textured outer surface 125 so as to improve purchase of the adhesive 130 to the device 120. The device 120 is shown with a crosshatched etching over the outer surface 125.

The cavity 135 shown intermediate the aperture 180 in the foundation 170 and the device 120 is shown filled with adhesive 130 so as to secure the device 120 into the aperture 180.

The adhesive is poured or injected into the cavity 135 ensuring that the cavity is filled so that no gaps remain where the adhesive 130 has not filled the space between the device 120 and the aperture 180.

The device 120 includes an 0-ring 160 to prevent the escape or egress of adhesive 130. In this way the pile is prevented from becoming adhered to the device by the adhesive 130. The 0-ring 160 is shown distally mounted on the device 120, arranged about the outer surface 125 thereby providing a cavity that extends almost the entire length of the device 120 ensuring maximum purchase and thereby being capable or withstanding greater forces such as when the load is being moved.

The jacking device 120 is arranged about a pile 100 therefore the device 120 is always at least the diameter of the pile 100. The proximal end of the pile when in situ receives a ram plate 110 upon which the displaceable member 140 is in contact when in use. The ram plate 110 serves as a protective plate atop the pile 100 being capable, of taking the forces associated with the displaceable member 140 so as not to damage the pile 100. Furthermore the ram plate 110 aids in the distribution of force across the proximal end of the pile 100.

The pile 100 is a permeation pile thereby also serving to stabilise the ground below the foundation 170 whilst also typically being of a lesser diameter of standard piles.

The jacking device 120 accepts an end cap 150. the end cap 150 includes an opening 155 thereby partially closing one end of the jacking device 120 when in use. The end cap 150 is threaded enabling the end cap 150 to be added to and removed from the jacking device 120.

Removal of the end cap 150 results in the provision of a larger access to the device channel 115 through which the pile 100 can be readily inserted and driven into the ground. In this way the jacking device 120 is first inserted into the aperture 180, the pile 100 is then inserted into the ground through the channel 115 in the devicel2o thus preventing any difficulty in retrospectively positioning the jacking device 120 about the pile 100.

Once the pile 100 has been inserted through the device 120 the end cap 150 is the located in the device 120, thereby partially closing the jacking device apart from the opening 155 provided for accepting the displaceable member 140.

The displaceable member 140 is shown being accepted through the end cap 150 thereby fully closing one end of the device. The displaceable member is inserted through the opening 155 so as to be arranged in use in contact with the ram plate 110. Therefore the displaceable member 140 is inserted until it abuts the ram plate 110.

Figure 2 shows the displaceable member 140 being threaded and accepted into a threaded opening 155 on the end cap so as to enable incremental adjustment of the displaceable member 140 by turning. In this way adjustment of the amount of displaceable member 140 inserted into the device is controlled by turning of the displaceable member 140.

Figure 3 shows the jacking device 120 in situ wherein the displaceable member 140 includes a hexagonal drive head 160 so as to enable the displaceable member 140 to be mechanically turned in order to move the device 120 and thereby the load 170 in respect of the pile 100.

Figure 4 reveals a load jacking system wherein a plurality of jacking devices 120, are arranged about a plurality of piles 100 forming jacking device and pile assemblies 190 -Al, A2, A3, A4. Therefore enabling fin adjustment of a load by separate adjustment of multiple jacking devices 120.

Each jacking device and pile assembly 190-Al, A2, A3, A4 is provided with a sensor 500 connected to a controller 400. The sensors 500 operate in conjunction with a datum 310 to as to measure displacement of the load. The movement is recorded by the controller 400. The movement recorded by each sensor 500 can be analysed in relation to another until the load is moved to the corrected position.

Figure 5a-c show progressive stages of load jacking wherein figure 5a shows floor that has sunken. Figure 5b shows reduced sagging of the floor. Figure 5c shows a floor that is at the corrected level position.

The void 300 is shown to increase from Figure 5b to 5c as the load is lifted.

The void 300 is back filled with a filler 305 so as to prevent return movement of the load.

Figure 6 shows a jacking assembly wherein the displaceable member 140 is located within a recess 125 on the ram plate 110. Figure 6 shows two ram plates, a first ram plate 11 OA arranged on the pile and a second ram plate 1 lOB situate below the first with a recess 125.

Figure 7 shows a centring tool 700 arranged in an aperture 180 wherein the shoulder 710 prevents the tool 700 from dropping through the aperture 180.

The tool includes a conduit 720 through which the pile 100 can be inserted so as to ensure it is inserted in the same axis as that of the aperture 180.

Figure 8 shows a piston assembly arranged within the device 120 wherein the piston 800 is arranged on the pile 100 and includes two outer mounted 0-rings 810A and BlOB. The 0-rings 810A/810B abut the inner face 135 of the device 120 so as to prevent escape of hydraulic fluid.

The end plate 150 includes a nipple 151 through which hydraulic fluid is added.

The invention has been described by way of examples only and it is appreciated that variation may be made to the aforementioned examptes without departing from the scope of the invention.