AU613485B2 - Wind bracing bracket - Google Patents

Description

A

AUSTRALIA

TT

PATENTS ACT 195 2 6 4 t COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Application Number: Lodged: Complete Specification Lodged: Accepted: Published: *t *E r Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: Address of Applicant: Actual Inventor: Address for Service: DALE VIVIAN BOUCHER 13 Trumper Street, Ermington, New South Wales, 2115, Australia DALE VIVIAN BOUCHER ARTHUR S. CAVE CO.

Patent Trade Mark Attorneys Level Barrack Street SYDNEY N.S.W. 2000

AUSTRALIA

*4 4 Complete Specification for the invention entitled WIND BRACING

BRACKET.

The following statement is a full description of this invention including the best method of performing it known to me:- 1 ASC 49 SO 07337 2 0132J/PP WIND BRACING BRACKET The present invention relates to brackets for use in bracing systems in buildings and in particular relates to a bracket which provides a versatile and adjustable anchorage for bracing members such as bracing rods.

The bracing bracket preferably comprises a channel section having arcuate walls providing an angular range of movement to enable adjustable setting of bracing rods which are used in a variety of applications in buildings.

Most structures require bracing to counter the effects of windloads, other applied live and dead loads and eccentric loading generally which may be applied to a structure.

o o o In heavy steel construction and in particular in space Papa frames, portal frames and trusses generally it is essential 0 p0 0o0 that bracing be employed to prevent any form of slewing *000 o o (lateral or longitudinal) in a structure under applied loading both during construction and upon completion. Many forms of S such bracing (which is usually configured diagonally) have been oc o used previously.

In steel structures generally the methods of anchorage of a 0a the bracing members (which are usually steel angle sections or -rods) have included conventional bolting or welding techniques.

P *The bracing members are generally designed to act as tension members when a parallelogram slewing effect occurs in a structure, however, in practice some Compressive forces would be applied to some diagonal bracing members. The forces generated in the bracing members are translocated to the anchorage means for the members. In many cases such as in -2- 1293j trusses the anchorage comprises a gusset plate at a node point in the structure. The plate is generally positioned so that all of the applied the forces intersect in the gusset plate so that there is no eccentricity of load about the connection.

One disadvantage of these plates is that the positioning of the plate itself relative to connection members and the position and size of the bolt holes relative to the connecting members is critical in both site and factory assembly. In this case there is virtually no facility to 'work' the members of the structure to ensure that mating members properly mate. The same situation applies with respect to the relative positioning of the members when welded connections are used.

A means has hitherto previously been developed whereby rods used in bracing are anchored by a specially configured bracket which enables sufficient versatility to allow slight rotation of bracing rods when they are being fitted into position in the particular structure. This provides a certain degree of licence in fitting of these members where there may S be slight errors or misalignments of the structural members during construction. Such brackets have been used previously in structures such as fascia trusses and in some portal frame structures.

'The brackets are designed so as to key into a specifically prepared slot in members to be braced in such a structure. The brackets have a key protruding from a base portion which engages the slot to provide shear resistance for the bracket when the bracing rods are under tension. However, these brackets by virtue of their shape and configuration do not have 3 1293j universal application.

It has not been previously known to use these brackets in conjunction with bracing structures having fabricated cold rolled steel purlin and girt sections. Purlin and girt sections are normally used in roof and wall construction respectively and must be braced to prevent longitudinal and lateral slewing.

It has previously been unknown to provide an effective bracing bracket for use with purlins and girts such that the bracket, when in situ, keys into slots preformed in both the purlins and/or girts and which also allows the facility for arcuate movement of the bracing member during installation.

,The present invention provides a bracket for use with and which is compatable with cold rolled purlin and girt sections thereby overcoming the limitations of application which existed t1*4 with the prior art bracket. In particular, the bracket of the t S present invention is newly configured so as to be compatible with both the standardised and usually pre-formed purlin and St girt slots and also to accommodate smaller sized bracing rods preferably within the range 06mm to 012mm. However, this S range is not to be construed as limiting to the rod size suitable for use with the bracket. The configuration of the tr' prior art bracket has at least one disadvantage in that there

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is excess clearance between the said slot edges and the bracket key or locating lug. This renders the prior art bracket both inefficient and largely unworkable in the present application.

The aforesaid prior art bracket has been fabricated for bracing rods of a diameter within the range 16mm to 30mm. If -4- 1293j i 'i these are used in the present application sloppiness of fit between rod and bracket will result along with sloppiness in the key/slot interfit.

A further disadvantage of the prior art bracket is related to the consequent reduction in the working angle when placed in standard purlins and girts.

One advantage of the present invention is that the bracket is configured and proportioned such that it conforms to the size of the rods which it is designed to accommodate. Further advantages are that the bracket will fit standard punchings in purlin and girt members and in addition, due to its particular shape and configuration it maximises the operating angle during insertion of the bracing members.

t The bracket is preferably made from a punched and folded S plate rather than a casting allowing versatility in relation to plate thickness and punching size without compromise to the

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structural integrity of the bracket.

The bracket is fabricated with the keying tabs or lugs S along the sidewalls of the bracket as opposed to the front of

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S the bracket thereby allowing the optimum operating angle.

4 In one broad form the present invention comprises an anchorage bracket for use in the anchorage of bracing members I, of the type utilised in building structures and in particular t steel structures, said bracket comprising an open channel formed by a base member and at least one arcuate wall member upstanding from and connected to said base member so as to form the open channel, said base member being adapted with a protrusion to act in engaging and keying to a member of a 5 1293j structure so as to provide shear resistance between said protrusion and said member wherein, when bracing is to be adapted to a structure, the bracing member penetrates both the structural member to be braced, the said base and the said open channel such that the bracing member protrudes beyond the extremity of said substantially arcuate wall member or members to enable movable engagement between a fastener and said bracing member such that said bracing member is allowed a degree of rotation about said extremity of said arcuate wall member or members and when tightened, said fastener holds said bracing rod and transfers tensile and or compressive loads in said rod to said bracket, said protrusion thereby preventing I r relative movement between said bracket and said member to be ttI SCCc braced.

In its broadest form the present invention comprises;

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a bracket for providing an anchorage for a bracing member of a ft 1£ S building structure characterised in that the bracket comprises a planar base having an opening therethrough, V a wall or walls each having an arcute extremity and being It 4 Sintegral with or connected to and extending from said planar it S" base, at least one key or lug integral with or connected to one or 4£I more of said walls and ad pted to engage a slot in a structural member to be braced, said opening being adapted to receive said bracing member, said arcuate extremity or extremities providing an engaging surface for an engaging fastener on said bracing member, said keys preventing relative movement between said bracket and -6- 1293j I .p said structural member to be braced when said engaging device tightly engages said arcuate extremities.

According to the method aspect, the invention comprises; a method of formation of a bracket adapted for use as an anchorage for a bracing member or members of a building structure said method comprising the steps of; providing a pre-cut and shaped planar blank having at least one arcuate edge; Punching or stamping out a portion of the blank at or near its middle so that the peripheral profile of the resultant Vtt hole defines at least one lug, outstanding from the periphery of the said hole and so that the lug or lugs are k4C.

,t c, opposite the said arcuate edge;

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bending the portion comprising the arcuate edge along a fold line so that the lug or lugs remain in the same plane as the resultant and corresponding wall or walls so formed; continuing the bending until the so formed wall or walls 4 are disposed normally to the plane of the remainder of the blank so that the said lug or lugs downwardly depend from said wall or walls

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In the preferred embodiment and according to one application the members to be braced are either purlins or girts having preformed slots therein which are adapted to receive the said protuberance or protrusion attached to said base of said bracket.

Also in the preferred embodiment, the bracket is fabricated by punching and folding a plate enabling accurate sizing of constituent parts.

In the preferred embodiment of the bracket the keying lugs 7 1293j are located on the sides of the bracket in the same plane as the walls as opposed to at the front or rear of the bracket thereby allowing the optimum operating angle to be effectively maintained and also facilitating more stability in the bracket in relation to force distribution.

The invention will now be described in more detail and with reference to the accompanying illustrations wherein Fig. 1 depicts a side elevational view of the bracing bracket according to the preferred embodiment.

1 Fig. 2 shows a plan view of a typical blank according to a trt preferred embodiment and from which the bracket is fabricated.

Fig. 3 shows a side view of the bracket following formation of t t the sidewalls.

t It Fig. 4 shows an end view of the bracket following formation of the sidewalls.

Fig. 5 shows an isometric view of the bracket according to the ri¢ preferred embodiment.

Referring to Fig. 1 there is shown a side elevational view of the bracket 1 of the present invention in situ. The figure shows the detail of the anchorage regime between the bracket 1 and the bracing rod 2 at an anchorage point on a member to be braced 3.

Member 3 is preferably a purlin or girt fastened to a building frame structure however, it is conceivable that such a member 3 could be a structural member of another type such as angle beam or column sections (not shown).

The bracket 1 comprises a planar base member 4 which lies 8 1293j h .11,111, i- I I- 11-1 .11-1-1- 1-1-1 I 1 1in apposition with surface 16 of the structural member 3.

Attached to and/or continuous with the base member 4 are arcuate wall members 5 and 6 (see also fig. 5) which provide a bearing surface 11 at their extremities for load transfer between the rod 2 fastener 7 and structural member 3. The bracket 1 is also adapted with keying or locating lugs 8 and 9 (see also fig. 5) which, when the bracket is in position locate the bracket 1 onto the member 3.

Figs. 2, 3, 4, and 5 show a series of views of the bracket (t tt rI C r 1 of the present invention according to the preferred embodiment. The figures show a developed view, a side view an t #c end view and an isometric view of the bracket i.

rtC From the developed view in figure 2 it can be readily seen tb t that the bracket is formed by punching out of the profiled portion 10 then bending the plate to form the base 4 and arcuate walls 5 and 6.

Figure 2 shows a plan view of a typical blank 12 used in Ct the formation of the bracket i. The preformed blanks are fabricated to form the shape shown. The blank comprises, according to the preferred embodiment, two arcuate edges 13 and 14 which provide a bearing surface for the fastener 7 (see figure 1).

The blank is first punched to form a hole 15 whose Speripheral profile defines lugs 8 and 9. Following punching the blank is folded along lines 17 and 18 to thereby form walls and 6. This results in hole 15 conforming to a substantially ovoid shape.

Figures 3, 4 and 5 show various views of the bracket formed from the blank depicted in figure 2.

9 1293j In use, the bracket 1 is first located on the member 3 to be braced by means of the locating lugs 8 and 9. Once these are set in receiving slots (not shown) in member 3, the rod 2 is fed through the hole 15 in bracket 1 resulting from the punching out of profiled portion 10 until the threaded portion extends beyond the arcuate extremities of the walls 5 and 6 so that fastener 7 can be threadably coupled with the rod 2.

When the rod 2 is under a tensile load the fastener 7 or an analogous alternative bearing element (not shown) bears on @0 a0 So the surfaces 13 or 14 of arcuate walls 5 and 6 respectively.

The tensile load naturally generates a shearing effect on the 0 0 O a b"e locating lugs by engagement with the member 3, however, this O* effect is resisted by the keying of the lugs thereby generating effective bracing in the structured members to which the bracket and rod is affixed; those being preferably purlins 0 and/or girts.

B It will be recognised by persons skilled in the art that 0° numerous variations and modifications can be made to the invention as broadly described herein without departing from o the overall spirit and scope of the invention.

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Claims (14)

1. A bracket for providing an anchorage for a bracing member of a building structure characterised in that the bracket comprises a planar base having an opening therethrough, a wall or walls each having an arcute extremity and being integral with or connected to and extending from said planar base, at least one key or lug integral with or connected to one or more of said walls and adapted to engage a slot in a structural member or members to be braced, rt l t said opening being adapted to receive said bracing member, t t t S said arcuate extremity or extremities providing an engaging r{to surface for an engaging fastener on said bracing member, said at least one key or lug preventing relative movement between said bracket and said structural member to be braced w he -saidengn er when said engaging deviee-tightly engages said arcuate St i extremities. c r t I,

2. A bracket according to claim 1 wherein the said structural member or members to be braced comprise purlin and girt members 1 of a building structure.

3. A bracket according to claim 2 wherein the said opening is located centrally of the planar base.

4. A bracket according to claim 3 further comprising two planar walls disposed in opposed relationship to each other which together with the planar base form a substantially U shaped channel.

A bracket according to claim 4 wherein the said at least is/or dAeendif'ong one key or lug is/are co-planar with and downwardly depend from the said walls. 11 *<U9^ /yy w-i

6. A bracket according to claim 5 wherein the said walls are configured so as to define a segment of a circle or semi-circle with the resultant arcuate portion forming a bearing surface for said engaging fastener.

7. A bracket according to claim 6 wherein the said engaging fastener comprises a bolt and washer assembly threadably attached to said bracing member.

8. A bracket according to claim 7 wherein there is one key or lug downwardly depending from each wall, with each of said keys Ia or lugs being located at or near the longitudinal midpoint of 4*4 each of said walls.

9. A bracket according to claim 8 wherein the key or keys comprise a substantially square or rectangular tab adapted to fit snugly within slots in or on said purlins and/or girts.

An anchorage bracket for use in the anchorage of bracing 4a members of the type utilised in building structures and in particular steel structures, said bracket comprising a channel o* or angle section comprising a base member and at least one arcuate wall member upstanding from the connected to said base member, said base member being adapted with a protrusion/s to act in engaging ind keying to a member of a structure to be braced so as to provide shear resistance between said protrusion and said member wherein, when bracing is to be adapted to a structure, the bracing member penetrates both the structural member to be braced and the said base, such that the bracing member protrudes beyond the extremity of said substantially arcuate wall member or members to enable movable engagement between a fastener and said bracing member such that said bracing member is allowed a degree of rotation about said 12 1293j extremity of said arcuate wall member or members and when i me.(-i6 e <r tightened, said fastener holds said bracing rfeIand transfers rme b er tensile and/or compression loads in said -edto said bracket, said protrusion/s thereby preventing relative movement between said bracket and said member to be braced.

11. A method of formation of a bracket adapted for use as an anchorage for a bracing member or members of a building structure said method comprising the steps of; providing a pre-cut and shaped planar blank having at least one arcuate edge; Punching or stamping out a profiled portion of the blank S" at or near its middle so that the peripheral profile of I ,4 the resultant hold defines at least one key or lug, outstanding from the periphery of the said hole and so that the key/s or lug/s are opposite the said arcuate edge; bending a portion of the blank comprising the arcuate edge along a fold line so that the key/s or lug/s remain in the same plane as the resultant and corresponding wall or walls so formed; continuing the bending until the so formed wall or walls are disposed normally to the plane of the remainder of the blank so that the said lug or lugs downwardly depend from said wall or walls

12. A method of formation of a bracket according to claim 1] wherein the punched hole results in two keys or lugs being formed one opposite each of said arcuate portions.

13. A method of formation of a bracket according to claim 11 wherein two arcuate walls are formed by folding of each about a fold line. 13 I i3/k

14. A bracket as hereinbefore described and with reference to the accompanying illustrations. A method of formation of a bracket as hereinbefore described and with reference to the accompanying illustrations. DATED this 9th day of May, 1989. DALE VIVIAN BOUCHER By His Patent Attorneys, ARTHUR S. CAVE CO. T t* ft t tt14 1293j