AU2005100373A4 - Foundation base plate - Google Patents

Description

06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 04/19 o FOUNDATION BASE PLATE Field of Invention This invention relates to foundation base plates for upright structural members.

\0Background Art Typically upright structural members such as piles, piers, stumps, columns and

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c r posts used in buildings are anchored at their bases by embedding them in holes or o trenches filled with concrete. Whilst this rudimentary arrangement normally produces sound structural results, it is labour intensive and is subject to the interruption by wet Sweather.

There is therefore a need for an improved method of founding upright structural members or at least a need for a useful alternative to the present method of doing so.

Statement of Invention Accordingly, the present invention provides in one aspect an integrally formed plastic support member for supporting an upright structural member in or on a ground surface, the support member including: a base plate having a relatively large footprint to spread the load of the upright structural member sufficiently to resist significant compressional movement of the ground immediately beneath said base plate; and an integral socket for receiving the lower end of said upright structural member, said socket having substantially upright side members to closely receive said upright structural member therebetween.

The upright structural member may be made of concrete, metal or timber. The upright structural member may be made from the locally preferred structural timber e.g. a treated pine post. The building structure supported by the upright structural member may be a building of light construction such as a pergola, deck, fence, rotunda, verandah or 1 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 05/19 o change pavilion whereby the live load applied in silu to the upright structural member is moderate. The upright structural member may be of any cross section, including circular, but will typically be square or rectangular as these are the common cross sections of IND posts, piers, pillars, piles or stumps used in the building industry.

The base plate may vary in thickness between the footprint defined by the socket n and the peripheral portions of the base plate outside the footprint defined by the socket.

SPreferably, the base plate is substantially stronger, e.g. by being thicker or having strengthening ribs, in the footprint defined by the socket than the peripheral portions of Sthe base plate whereby the support portion of the base plate immediately beneath the upright structural member is capable of withstanding substantial compressive loads.

The upright side members preferably define a box to closely receive the lower portion of the upright structural member. At least one of the upright side members may have a vertical planar inner wall surface, or may have a slight taper so that the socket widens slightly in the upwards direction. To improve the strength of the socket, the inner and outer wall surfaces of the socket may converge upwardly from a wider base and taper towards the upper portions of the upright side members. Accordingly, the one or more upright side members may have an inclined outer wall surface whereby the upright side member tapers upwards from a wide and sturdy base.

The upright side members may be reinforced by lateral structures extending between the outer wall surfaces of the upright side members and the upper surfaces of the peripheral portions of the base plate outside the footprint of the socket. The reinforcing structures may be in the form of gussets, ribs or struts. There may be one or more reinforcing structures extending from each upright side member. The reinforcing structures may include corner structures extending generally radially from the centre of 2 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 06/19 o the socket outwardly to terminate on the upper surface of the peripheral portion of the base plate.

The outer base of the upright side members may be strengthened by a bead or INs strip at the region where the upper surface of the peripheral portions of the base plate meet the external surfaces of the upright side members to provide further structural

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support, noting that the largest load applied to the socket is in the lower portions of the 0 upright side members where twisting and torsional stresses are most likely.

t' According to a second aspect of the invention there is provided a building O structure erected over a ground surface, the structure having multiple upright foundation members extending upwardly from the ground surface or from below the ground surface, the structure further including above ground structural members extending between and supported on respective pairs of foundation members, wherein each of said foundation members has at a bottom end thereof a respective integrally formed plastic support member located in or on the ground surface and spreading throughout the area thereof the weight of the respective foundation member and weight of the above ground structure, each plastic support member including: a base plate having a relatively large foot print spreading the load applied by the foundation member sufficiently to resist significant compressional movement of the ground immediately beneath the base plate during erection of the building structure; and an integral socket receiving therein the lower end of the respective foundation member, the socket having substantially upright side members closely receiving therein the lower end of the respective foundation member.

Brief Description of the Drawings Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However, it is to be understood 3 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 07/19 o that the features illustrated in and described with reference to the drawings are not to be C construed as limiting on the scope of the invention. In the drawings: Figure 1 is a perspective view of a sole plate according to a first embodiment; IND Figure 2 is a perspective view of a sole plate according to a second embodiment; Figure 3 is a perspective view of a sole plate according to a third embodiment; C€ Figure 4 is a perspective view of a sole plate according to a fourth embodiment; M Figure 5 is a side elevation of a sole plate according to a fifth embodiment of the 2- invention; SFigure 6 is a top perspective sectional view of a sixth embodiment of the invention; Figure 7 is an underneath perspective view of the sixth embodiment of Figure 6.

Referring to Figure 1. there is shown a first embodiment of the invention in its simplest form. A sole plate 1 includes a circular base plate 2 on which is centrally mounted a box shaped open topped socket 3. 'The socket 3 comprises four upright planar walls 4 to define a cavity 5 suitable to receive the lower end of a square or rectangular sectioned stump or pier e.g. made of timber or concrete, preferably with a close interference fit. There may be a slight taper of the walls 4 of the socket to facilitate removal of the article from a manufacturing mould, and to promote the interference fit of the stump within the socket.. As such stumps or piers are typically right angled at their end edges, the socket 3 correspondingly includes right angled corners where the internal surfaces 6 of the walls 4 meet the upper surface 7 of the base plate 2 within the footprint of the socket 3. The base plate 2 is circular in plan view so that it is in the form of a disc. The thickness of the base plate 3 may be about 4 mm and is uniform throughout.

Similarly, the side walls 4 are uniformly thick and, depending on the live load of a particular application, may be between 4 mm and 15 mm thick.

4 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 08/19 0 In the second embodiment shown in Figure 2, a sole plate 10 includes a square C base plate 22 on which is centrally mounted a truncated pyramid shaped socket 23. The side walls 24 of the socket 23 have upright internal surfaces 26 whereby the socket 23 Sdefines an internal space 25 which is square or rectangular to receive a correspondingly shaped lower portion of a stump or post. The outer surfaces 28 of the four walls 24 are M inclined to the vertical whereby each of the walls 24 has a wider base 29 and a narrower C top edge 21.

0 SReferring to Figure 3, the third embodiment of the invention provides a sole plate including a generally diamond shaped base plate 32 which, in plan view, generally C 10 follows the contours of the peripheral edges of a socket 33 mounted thereon. The socket 33 has the generally truncated pyramidal shape ofthe socket 23 shown in Figure 2. but additionally includes generally triangular shaped corner gussets or ribs 8 to reinforce the socket 33 structure and also the base plate 32 against bending upwardly when a load bears down through the stump through the socket onto the middle area of the base plate.

The base plate 32 includes a peripheral edge 9 which includes concave portions between the corner ribs 8 to save on material per unit. The concave recesses 10 do not compromise in any significant way the structural integrity of the base plate 32. The outer corners 11 of the base plate 32 provide it with the required footprint whereby to stably support the post or stump on the ground or in a hole as the case may be.

In the fourth embodiment shown in Figure 4, a sole plate 40 is provided with a generally truncated pyramid shaped socket 43 of the same general structure as the socket shown in Figure 2, centrally mounted on a generally square or rectangular base plate 42. The side walls 44 of the socket 43 are reinforced by a number of side gussets or ribs 12 extending from the external faces 48 of the side walls 44 and the top surface of the peripheral portions 13 of the base plate 42. The side ribs 12 may be anywhere between 1 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-99901337 PATENT ATTORNEY SERV PAGE 09/19 Smm and 4 mm thick and may be varied in width, depending on the application and the C expected live load applied by the post or stump. The side ribs 12 may be located close to the corners 14 of the socket 43 or may be spaced therebetween as shown. The person Sskilled in the art will appreciate that a wide variety of rib configurations will 0 5 satisfactorily reinforce the side walls 44 and the peripheral portions of the base plate. For example, the rib may be in the Form of an inclined continuous wall having a top edge e and the peripheral portions of the base plate extending around the periphery of the socket 43 and its top edge secured to each side wall 44 intermediate its height. The side ribs 12 o are illustrated in the form of struts but may be of a generally triangular shape as shown in cN 10 Figure 5 where stronger reinforcement is required.

Referring to the fifth embodiment shown in Figure 5, there is provided a sole plate 50 including a base plate 52 on which is mounted a socket 53 of the same general truncated pyramid shape as the socket 23 shown in Figure 2. The socket 53 includes internal walls 56 which, together with the inner upper surface 15 of the base plate 52 defined by the internal walls 56, define internal space 55. The side walls 54 of the socket 53 include an internal void 16 which includes internal ribs or grids (not shown) to provide the necessary structural rigidity whilst saving on material per unit. The side walls 54 are further strengthened by side gussets or ribs 16 which, in side view, have a generally inwardly curved top edge and join the top surface 63 of the base plate 52. A peripheral bead 17 extends around the outer base of the socket 53 and the outer surfaces 58 of the side walls 54. The corner reinforcing ribs 18 of the fifth embodiment are similar to those shown with respect to the third embodiment in Figure 3.

The bead 17 provides structural support for the base of the side walls 54 which is potentially subject to the highest loads which may result from strata movement during the life of the building structure. The central portion 15 of the base plate 52 is significantly 6 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-99901337 PATENT ATTORNEY SERV PAGE 10/19 g thicker than that of the peripheral portions 64 to withstand the higher compressive forces C imposed on the socket 53 by the post or stump at the centre of the box plate 52 at the bottom of the socket 53. Furthermore, as the requirement for strength decreases towards Sthe periphery of the base plate 52, the thickness of the peripheral portion 64 may slightly taper towards its outer edges In the sixth embodiment shown in Figures 6 and 7. the base plate 62 is of shallow c frusto conical shape in its peripheral regions 74 beyond the side walls 75 of the socket 73. As in earlier embodiments, strengthening gussets or ribs 77, 78 are provided which in this embodiment are provided both along the walls 75 and at the corners of the socket.

C 10 The shallow frusto conical shape of the base plate 72 provides greater resistance to bending of the periphery 74 thus assisting spreading of the compressive load applied by a post or stump received within the socket 73. As seen in the underneath view of Figure 7, integral strengthening ribs 79 are provided on the concave bottom face of the face plate 72 with these ribs extending radially to the sides and to the corers of the base plate.

in use, the sole plate may be placed directly on horizontal ground at the location required for the upright structural member. To further stabilise the placement of the sole plate pegs may be hammered into the ground through apertures 66 located in the peripheral portions. If a structure is to be erected on a concrete slab, masonry anchor bolts may be used to anchor the sole plate to the slab. Such an arrangement will be suitable for many lighter building structures such as carports, pergolas or rotundas.

However, for structures which impose a heavier load on the pier or stump, a trench or hole may be dug to specifications or regulations (such as for example, 450 mm deep) and the sole plate placed at the base of the hole or trench. In placing the sole plate, it is desirable to ensure that the base plate is horizontal to ensure that the post or pillar is substantially vertical. Once the post or pillar is mounted into the socket and is vertical, 7 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 11/19 soil can be used to fill the hole or trench to stabilise the foundation. As the sole plate is 0 ]intended only for light building structures, generally it will not be necessary to partially or completely fill the bole or trench with concrete but, of course, such an installation method may be advantageous in some applications, particularly where some earth movement is anticipated, such as in loamy soil.

She support member of the present invention may be manufactured from any Ssuitable plastics material. Polyethylene and polypropylene may be suitable plastics materials. The manufacture preferably involves a moulding process in which two facing dies define the mould cavity. Slight tapering of the socket walls, strengthening ribs and gussets are desirable to assist ejection of the moulded article upon separation of the dies.

A slight taper within the cavity of the socket can also facilitate a positive interference fit with the end of a stump, pillar. ete, enabling the support member to be readily fitted to a stump, etc. before the stump is placed in the ground.

In use of the support member according to the invention, the erection of a relatively light weight structure such as a verandah, deck, fence, pergola, carport, etc can process to completion usually at a faster rate than present practices which involve pouring concrete foundations around support stumps, pillars, etc. In conventional present practices, one day is usually allowed for the concrete used in the foundations to set sufficiently before erection of the structure above ground continues. Using the present invention, the support member obviates the needs for poured concrete foundations enabling stumps or the like to be located and erection of the structure above ground to immediately progress.

Throughout the specification and claims the word "comprise" and its derivatives are intended to have an inclusive rather than exclusive meaning unless the context requires otherwise.

8 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 06/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 12/19 Orientational terms used in the specification and claims such as vertical, horizontal, top, bottom, upper and lower are to be interpreted as relational and arc based on the premise that the component, item, article, apparatus, device or instrument will Susually be considered in a particular orientation, typically with the socket facing upwardly.

It will be appreciated by those skilled in the art that many modifications and n Yvariations may be made to the embodiments described herein without departing from the 0 spirit and scope of the invention.

09 o 9 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06

Claims (1)

1. 61-3-98901337 PATENT ATTORNEY SERV PAGE 13/19 The claims defining the invention are as follows: 1i. An integrally formed plastic support member for supporting an upright structural t member in or on a ground surahce, the support member including: S(a) a base plate having a relatively large footprint to spread the load of the upright structural member sufficiently to resist significant compressional movement of r- the ground immediately beneath said base plate; and S(b) an integral socket for receiving the lower end of said upright structural member, said socket having substantially upright side members to closely receive said Supright structural member therebetween. 2. Asupport member according to claim 1, wherein said base plate is stronger in the footprint defined by said socket than the peripheral portions of said base plate, projecting laterally beyond the side members of the socket. 3. A support member according to claim I or 2, wherein each of said upright side members has at least one of its inner wall surface and its outer wall surface inclined so that it has a narrowing taper in the upwards direction. 4. A support member according to any one of the preceding claims, wherein one or more of said upright side members are reinforced by lateral structures extending between one or more of the outer wall surfaces of said upright side members and upper surfaces of the peripheral portions of said base plate outside the footprint of said socket. 5. A building structure erected over a ground surface, the structure having multiple upright bfundation members extending upwardly from the ground surface or from below the ground surface, the structure further including above ground structural members extending between and supported on respective pairs of foundation members, wherein each of said foundation members has at a bottom end thereof a respective integrally formed plastic support member located in or on the ground surface and spreading COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06 OG/05/2005 14:54 61-3-98901337 PATENT ATTORNEY SERV PAGE 14/19 throughout the area thereof the weight of the respective foundation member and weight of the above ground structure, each plastic support member including: a base plate having a relatively large foot print spreading the load applied by the foundation member sufficiently to resist significant compressional movement of the ground immediately beneath the base plate during erection of the building structure; and an integral socket receiving therein the lower end of the respective foundation member, the socket having substantially upright side members closely receiving therein the lower end of the Srespective Foundation member. 11 COMS ID No: SBMI-01235169 Received by IP Australia: Time 15:00 Date 2005-05-06