Technical Field

[0001] Embodiments relate generally to timber piling systems and methods. Some embodiments relate to timber piles and methods of making and using such piles. Embodiments also relate to pile driving helmets and kits comprising the same for use with described timer piling embodiments. In particular, embodiments relate to piles formed of engineered timber or natural solid timber.

Background

[0002] Footings for buildings and other structures are commonly required in order to stably support large weights above a ground surface.

[0003] For deep foundations, piles may be used. Such piles may be formed of timber, steel, concrete or a combination of steel and concrete, for example. Steel and concrete piles can be somewhat expensive to fabricate and transport, while timber piles can be subject to rotting or wear and may not be considered to have the requisite strength for all applications. Hardwood timber species traditionally used for timber piling are now becoming scarce. Environmental concerns and access are making traditional timber piles relatively expensive and difficult to procure in larger volumes. Traditional timber piles are also limited by length. The overall pile length is limited by the saw mill's infrastructure and its ability to transport the pile.

[0004] It is desired to address or ameliorate one or more shortcomings of or associated with prior timber piles or their methods of use or construction, or to at least provide a useful alternative thereto.

[0005] Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

[0006] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application.

Summary

[0007] Some embodiments relate to a timber pile for receipt in the ground to support a structure, wherein the pile has a cruciform shape in cross-section. The timber pile may be formed of engineered timber.

[0008] The pile may be formed of at least two timber beams coupled together. The pile may be elongate along a longitudinal axis and the cruciform shape may be provided in a lateral cross-section. A length of the pile along the longitudinal direction may be between about 5 to about 20 times a maximum lateral width of the pile.

[0009] A timber material of the pile may be treated with a preservative substance. The preservative substance may comprise chromated copper arsenate (CCA), for example. The timber material may be treated with the preservative substance prior to formation of the pile.

[0010] The timber material may comprise a plurality of pieces of glued laminated timber.

[0011] The pile may comprise a first elongate beam extending in a longitudinal direction of the pile and having a first width in a first lateral direction and a second width in a second lateral direction, the second lateral direction being generally perpendicular to the first lateral direction, the first width being greater than the second width. The pile may comprise a second elongate beam and a third elongate beam and the second and third elongate beams may be coupled to opposed sides of the first elongate beam and aligned in the second lateral direction.

[0012] The second elongate beam may be coupled to the first elongate beam by at least one dowel received in a respective at least one slot in one face of the first elongate beam and a similarly-dimensioned respective at least one slot in the second elongate beam. The third elongate beam may be coupled to the first elongate beam by at least one dowel received in a respective at least one slot in an opposite face of the first elongate beam and a similarly-dimensioned respective at least one slot in the third elongate beam.

[0013] The second and third elongate beams may be coupled to the first elongate beam by a plurality of fasteners. The second and third elongate beams may be coupled to the first elongate beam by an adhesive substance. The adhesive substance may be formed by a two-part epoxy. A length of the pile may be at least 4 meters.

[0014] Some embodiments relate to a method of providing a footing, comprising:

driving at least one timber pile into the ground, wherein the at least one timber pile has a cruciform shape in a lateral cross-section.

[0015] Some embodiments relate to a method of forming a timber pile, comprising:

forming timber material into an elongate pile having a cruciform shape in a lateral cross-section. The timber material may comprise engineered timber material.

[0016] The method may further comprise treating the engineered timber material with a preservative prior to the forming. The forming may comprise coupling a first elongate beam with a second elongate beam and a third elongate beam in a configuration that has the cruciform shape in a cross-section. [0017] Some embodiments relate to a timber pile, comprising an elongate body extending along a longitudinal axis and having a non-circular shape in lateral cross- section, the body comprising timber material of a first orientation extending longitudinally along a first lateral axis and timber material of a second orientation extending longitudinally along a second lateral axis, wherein the second lateral axis crosses the first lateral axis at a longitudinal centre-line of the body. The first lateral axis may cross the second lateral axis approximately at a right angle.

[0018] Some embodiments relate to a pile driving helmet, comprising: an impact- receiving portion and a cover portion coupled to the impact-receiving portion, the cover portion comprising walls defining a cavity, wherein the cavity has a cruciform shape in cross-section to receive an end of a pile that has a corresponding cruciform shape in cross-section.

[0019] The pile driving helmet may further comprise an elastomeric cushioning element in the cover portion to disperse impact stress on the pile.

[0020] Some embodiments relate to a kit comprising the timber pile described and/or claimed herein and the helmet described and/or claimed herein.

Brief Description of Drawings

[0021] Embodiments are described in further detail below, by way of example and with reference to the accompanying drawings, in which:

[0022] Figure 1 is a side view of a timber pile according to some embodiments;

[0023] Figure 2 is an end view of the timber pile of Figure 1 ;

[0024] Figure 3 is a perspective view of the timber of Figure 1 ;

[0025] Figure 4 is a cross- sectional view of the timber pile of Figure lalong line A- A of Figure 1 ; [0026] Figure 5A is a side view of a helmet for use in driving the timber pile of Figure 1;

[0027] Figure 5B is a perspective view of the helmet of Figure 5A; [0028] Figure 6 A is a plan view of the helmet of Figure 5 A;

[0029] Figure 6B is a cross- sectional view of the helmet of Figure 5A along line A-A of Figure 5A;

[0030] Figure 7A is a cross- sectional view of the helmet of Figure 5A along the line B-B of Figure 5A; and

[0031] Figure 7B is a bottom view of the helmet of Figure 5 A. Detailed Description

[0032] Embodiments relate generally to elongate timber piles and methods of making and using such piles. In particular, embodiments relate to piles having a cruciform (cross) shape in cross-section and formed of engineered timber. In some embodiments, the timber pile may be formed from natural, solid timber, rather than engineered timber. In some embodiments, the cross shape may have a configuration resembling two cross-beams, optionally of substantially the same lateral length in cross-section, that are approximately right-angled with respect to each other. In other embodiments, the cross-shaped configuration may have an orientation that defines opposing obtuse angles and opposing acute angles.

[0033] Referring firstly to Figures 1 to 4, a timber pile 100 according to some embodiments is described in further detail. As is evident from Figures 2, 3 and 4, the timber pile 100 has a cruciform shape in cross-section, where the cross-section is taken as a lateral cross-section in a direction perpendicular to a longitudinal (lengthwise) axis or direction of the pile 100 (best seen in Figures 1 and 3). [0034] By use of the cruciform shape, the timber pile 100 of the depicted embodiments may have a ground contact surface area that is about 21.5% greater than a round pile having the same maximum lateral dimension (i.e. diameter). This greater contact surface area of such embodiments allows the pile 100 to have greater skin (ground contact) friction relative to the surrounding ground and thus up to 21.5% greater bearing capacity. The cruciform shape of such embodiments also requires about 28% less volume of timber material than a round pile of the same maximum lateral width and even less timber material than a pile of square cross-section with the same lateral width. Additionally, the cruciform shape tends to better resist longitudinal twisting and bending away from vertical during driving of the pile into the ground, as compared to a round pile.

[0035] The material from which the timber pile 100 is formed may be an engineered timber material, such as a plurality of pieces of glued laminated timber, for example. This material is sometimes called "glulam". For example, the engineered timber material of pile 100 may include radiata pine glulam. The use of glulam timber material allows easily procurable short sections of timber to be bonded together to make longer sections. This is in contrast to solid timber, which requires long single sections that are more difficult and costly to source. Both solid and engineered timber materials can be trimmed or shaped post-installation using standard wood-working equipment.

[0036] The timber material may be pre-treated with preservative substances before being formed into the timber pile 100. For example, radiata pine glulam material allows a relatively high level of chemical preservative treatment acceptance, has a relatively light weight (approximately 550 kilograms per cubic meter), it can be sourced as an environmentally sustainable material made from farmed timber and it can be readily worked with appropriate tools. Such timber material can be readily treated with a preservative such as chromated copper arsenate (CCA). Alternative timbers of different densities can be used instead of radiata pine as a timber source material, such as timber having in the range of 400-700 or 500-600 kg per cubic metre on average. [0037] In traditional construction practices, when building foundations, particularly concrete foundations, it is common to require significant plant hire, removal of spoil, significant build time and significant waiting time to pour concrete and wait for it to cure. Further, delays may be encountered in transporting the concrete to site in concrete mixing trucks. Thus, there are delays and disadvantages inherent in traditional foundation building using concrete footings or piles.

[0038] Timber pile 100 is formed to have a generally elongate construction, with a major axis along the longitudinal center line 115 (shown as a point in Figure 2) of the body of the timber pile 100. The cruciform shape of the timber pile 100 may be formed in a number of ways but at the least should define first and second lateral axes that cross each other at about the longitudinal center line 115. As shown in Figure 2, the first and second lateral axes 107, 108 may cross each other at approximately at a right angle, although some variation in the angle may be permitted while achieving substantially the same structural benefits. In other embodiments, the first and second lateral axes 107, 108 may cross each other at non-right angles, defining opposing obtuse angled inside corners and opposing acute angled inside corners. The timber pile 100 may thus define four longitudinally extending fins that project in different directions from a central body portion that contains the longitudinal center line 115 where the first and second lateral axes 107, 108 cross each other. The fins may extend laterally from the central body portion by about the same distance. Such fins provide an increased contact surface area when compared to round piles having the same maximum width in cross-section.

[0039] The timber pile 100 has a generally uniform cross-section along its length, between a first end 102 and an opposite end 104. The timber pile 100 has a generally flat cruciform-shaped face 103 at the first end 102 and a generally flat cruciform- shaped face 105 at the second end 104, consistent with the substantially uniform cross- section.

[0040] Some embodiments of timber pile 100 may be formed by coupling at least two timber beams together. For example, where beams with opposing slotted ends are mated together, only two beams are needed to form the timber pile 100. Other embodiments formed with three beams are illustrated in Figures 1 to 4. Still other embodiments may form the timber pile 100 in other ways, examples of which are described in further detail below. For the timber pile embodiments shown in Figures 1 to 4, the timber pile 100 has a major beam 110 having a lateral extent coincident with the first lateral axis 107. Second and third minor beams 112 and 114 are coupled on opposite major side faces of the major beam 110 so as to be aligned with each other along the second lateral axis 108. The second lateral axis 108 thus extends through the first, second and third beams 110, 112 and 114.

[0041] The first and second minor beams 112, 114 may be coupled to the major beam 110 by use of a plurality of dowels 120 received in facing slots extending inwardly from facing side surfaces of the major beam 110 and minor beams 112, 114, as illustrated in Figure 2 and Figure 4. Each of the first and second minor beams 112, 114 may be coupled to the major beam 110 by a plurality of dowels at locations spaced along the length of the beams. Such dowels 120 may be formed as wood plates, for example. Such dowels 120 may be formed of a laminated material, such as plywood, and have a width, length and thickness suited to the scale and dimensions of the timber pile 100.

[0042] Dowels 120 serve an alignment function and a connection function. Further, the dowels 120 may assist in providing sheer strength to resist shearing between the major beam 110 and the minor beams 112, 114.

[0043] The major beam 110 may have a generally rectangular cross-section, with a first width and a first lateral direction and a second width and a second lateral direction perpendicular to the first lateral direction, where the first width is greater than the second width. The minor beams 112, 114 may have a generally square cross-section. The timber pile 100 may be substantially symmetrical about each of the first and second lateral axes 107, 108. [0044] In one example, the timber pile 100 may have a length of about 4 meters and a maximum lateral width of about 600 millimetres. The central portion may have a cross-sectional area of about 200 millimetres by 200 millimetres, for example. Each of the fins may project from the central portion by about 200 millimetres, for example. The dowels 120 may have a length of about 600 millimetres and four such dowels may be used to bond the major beam 110 with the minor beams 112, 114, separated by gaps of about 400 millimetres. Additionally, a plurality of wood screws 132 may be inserted through the minor beams 112, 114 into the major beam 110 at lengthwise spaced positions close to a corner formed by the interface of the minor beams 112, 114 with the major beam 110. This is best illustrated in Figure 2. The screws 132 may also be inserted into the minor and major beams 110, 112, 114 at the end faces 103, 105 and at approximately 600 millimetre intervals along the length of the timber pile 100 on each side of the minor beams 112, 114.

[0045] A suitable wood bonding adhesive can be used to adhere each of the dowels 120 in place within the slots formed in the major beam 110 and the minor beams 112, 114. Thus, the slots may be formed with a few millimetres clearance in width and depth to accommodate the presence of the adhesive. A suitable adhesive may be a two part epoxy resin, such as TECHNIGLUE® from ATL Composites. Additionally, adhesive may be applied to the facing surfaces of the lengthwise coupling interface between the major beam 110 and the minor beams 112, 114 in order to more strongly bond the minor beams 112, 114 onto the major beam 110. For that adhesive, a similar two part epoxy resin, such as TECHNIGLUE®, may be used.

[0046] Although a combination of three means of coupling the minor beams 112, 114 to the major beam 110 are described and illustrated (i.e. fasteners, such as screws 132, connectors, such as dowels 120, and adhesives), fewer or more means of coupling may be used. Further, alternative fasteners and connectors may be employed as part of the coupling means.

[0047] Instead of coupling multiple beams together, alternative methods of making the cruciform pile 100 may include: mechanical shaping methods, such as routing the cruciform shape from a billet of timber material; lamination methods, such as layering and adhering a multitude of veneers that are glued and pressed to form the engineered timber material having the desired cruciform shaped cross-section; and assembly from multiple dovetailed pieces having male and female connections (that can also be glued). A further method of forming the timber pile 100 may include joining multiple pieces together using different shaped dowels, such as cylindrical dowels. A further alternative may include the use of vacuum forming to combine a number of veneers preformed into a desired shape and then sucked into place under vacuum pressure and adhered to each other with a suitable bonding agent.

[0048] Although Figures 1 to 4 show a timber pile 100 having a perfect square cross shape in cross-section with square fins and square corner cavities, the fins need not be perfectly squared and each of the corner cavities may define a corner angle of greater than 90 degrees. Further, in some embodiments, the timber pile 100 may have a greater length along one of the lateral axes 107, 108 than the other lateral axis.

[0049] Embodiments of timber pile 100 may be formed to have a length along the longitudinal direction between about 5 to about 20 times a maximum lateral width of the pile. In some embodiments, the length of the pile may be about 6 to 7 times the maximum lateral width of the pile. The precise proportions of the timber pile 100 may vary, depending on design requirements.

[0050] In some embodiments, the timber pile 100 may have one or more cushioning elements (not shown) fastened or otherwise attached to one or both end faces 103, 105. The timber pile 100 may have multiple spaced cushioning elements disposed on and attached to either end face 103, 105. The one or more cushioning elements may be fastened to one or both of the end faces 103, 105 by mechanical or chemical fastening means, for example including nails, screws, bolts and washers in recesses in the outer surface, adhesives or other bonding agents. Further fastening means may include frictional attachments, such as those that may involve a compressive interference fit of part of the cushioning material within one or more recesses in the end face 103, 105. [0051] The cushioning elements may have a cruciform shape or configuration that is substantially the same as or at least resembles the cross-sectional cruciform shape of the timber of the pile 100, although some variation of the shape of the cushioning elements is acceptable while still providing an appropriate cushioning function against impact forces from a pile driver. For example, the cushioning elements may have a cruciform shape or configuration (including multiple separate pieces of cushioning material) that fits within the dimensions of the end faces 103, 105. The cushioning elements may comprise substantially the same elastomeric material and/or configuration as the cushioning element 530 describe below and shown in Figure 7A. For example, the cushioning element may comprise a single or double layer of Chutex rubber.

[0052] Referring now to Figures 5 A, 5B, 6 A, 6B, 7 A and 7B, a pile driving helmet 500 for driving the timber pile 100 is shown and described in further detail. The helmet 500 may form part of a kit that, together with a plurality of the timber piles 100, can be used to provide a foundation with multiple timber piles 100 placed in the ground at spaced locations.

[0053] The helmet 500 can be used to drive multiple timber piles 100 into the ground in series (end-on-end) in the same location, where the vertical depth achievable by a single timber pile 100 is not considered to be adequate and a further length of pile is desired to be driven in to the ground. Multiple timber piles 100 can thereby be concatenated lengthwise to effectively provide a single pile to a depth to suit a particular application.

[0054] Where multiple piles 100 are driven down end-on-end, one or more shaped guides can be affixed or placed on the top end of the lower pile 100 as the next pile is driven down on top of the lower pile 100, to guide and appropriately locate the lower end of the next pile in alignment with the upper end of the lower pile. Such guides may include angled plates received in correspondingly angled corner recesses of the upper end of the lower pile 100. The shaped guides may be affixed only to an end of one of the two adjacent piles 100 or alternatively they may be affixed to both adjacent ends. [0055] The helmet 500 comprises an impact-receiving section 510 at an upper end thereof and a cover portion 520 at a lower end thereof. The cover portion 520 is coupled to the impact-receiving portion 510 by an intermediate plate portion 518. The cover portion 520 has a hollow cylindrical or annular shroud 522 extending downwardly from the intermediate plate 518. The helmet 500 may have coupling lugs 525 projecting from the shroud 522 at diametrically opposite locations.

[0056] The impact-receiving portion 510 comprises a plurality of outer plates 514 and internal cross plates 516a, 516b arranged vertically to define an upper impact surface 512. The upper impact surface 512 may be defined by the upper edges of the vertically oriented plates 514, 516a, 516b so that vertically downward impact forces transmitted through the impact surface 512 are transmitted downwardly through the vertically extending parts of the plates 514 into the intermediate plate portion 518. The vertical plates 514 may surround the internal crossed vertical plates 516a, 516b that may be welded together and to the vertical plates 514 in order to provide a relatively strong structure for transmitting the impact forces to lower parts of the helmet 500.

[0057] The shroud 522 circumferentially surrounds a series of internal vertical plates 524 that, together with the shroud 522, define a cavity 526 having a substantially cruciform shape in cross-section that is sized to receive one end of the timber pile 100. The cavity 526 is sized to be approximately 5 to 15%, optionally 10%, larger than the cross-sectional dimensions of the timber pile 100, so that the helmet 500 can be easily fitted down over an upward end of the timber pile 100 to drive it downward. Thus, for a timber pile 100 having a fin of about 200 mm in width, the corresponding receiving part of the cavity 526 may be about 210 to about 230 mm, optionally about 220 mm, for example.

[0058] The helmet 500 may further comprise a cushioning element 530 disposed close to or adjacent an upper end of the shroud 522, close to the intermediate plate 518, to act as a cushioning element to distribute impact stresses transmitted through the intermediate plate 518 to an end face of the pile 100. The cushioning element 530 may be provided in the helmet 500 instead of or in addition to any cushioning element attached to either end face 103, 105 of the timber pile 100. The cushioning element 530 may comprise an elastomeric material, which may comprise rubber or plastic or both. One example of material that can be used for the cushioning material 530 is Chutex rubber of about 40 Durometer. One or two layers of Chutex of about 12 mm thickness can be used, for example.

[0059] The helmet 500 may be generally formed of strong metal materials, such as steel, other than for the elastomeric material of the cushioning element 530. The helmet 500 may be formed by welding metal plates together, for example. Alternatively, some of the parts of the helmet 500, such as the cover portion 520, may be moulded.

[0060] Numerous variations and/or modifications may be made to the above- described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.