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AU598684B2 - Reinforced laminated timber - Google Patents

Reinforced laminated timber Download PDF

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Publication number
AU598684B2
AU598684B2 AU18925/88A AU1892588A AU598684B2 AU 598684 B2 AU598684 B2 AU 598684B2 AU 18925/88 A AU18925/88 A AU 18925/88A AU 1892588 A AU1892588 A AU 1892588A AU 598684 B2 AU598684 B2 AU 598684B2
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Australia
Prior art keywords
timber
timber member
laminated structural
laminations
rods
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AU18925/88A
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AU1892588A (en
Inventor
Robert David Eaton
Guy Peter Gardner
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Priority to AU18925/88A priority Critical patent/AU598684B2/en
Priority to CA000582611A priority patent/CA1307731C/en
Priority to NZ226918A priority patent/NZ226918A/en
Priority to JP88284826A priority patent/JPH01287354A/en
Publication of AU1892588A publication Critical patent/AU1892588A/en
Application granted granted Critical
Publication of AU598684B2 publication Critical patent/AU598684B2/en
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    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04CSTRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C3/00Structural elongated elements designed for load-supporting
    • E04C3/02Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; Braces
    • E04C3/12Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; Braces of wood, e.g. with reinforcements, with tensioning members
    • E04C3/18Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; Braces of wood, e.g. with reinforcements, with tensioning members with metal or other reinforcements or tensioning members
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04CSTRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C3/00Structural elongated elements designed for load-supporting
    • E04C3/30Columns; Pillars; Struts
    • E04C3/36Columns; Pillars; Struts of materials not covered by groups E04C3/32 or E04C3/34; of a combination of two or more materials
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04CSTRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C3/00Structural elongated elements designed for load-supporting
    • E04C3/38Arched girders or portal frames
    • E04C3/42Arched girders or portal frames of wood, e.g. units for rafter roofs

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Rod-Shaped Construction Members (AREA)

Description

598684 COMMONWEALTH OF AUSTRALIA The Patents Act 1952-1969 Name of Applicant(s): GUY PETER GARDNER and ROBERT DAVID
EATON
Address of Applicant(s): 14 Nansen Street, Northgate, in the State of Queensland, 4013, Commonwealth of Australia and 16 Emerald Street, Clontarf, in the State of Queensland, 4019, Commonwealth of Australia 4, o 4 000a 4, 04I 0~i Actual Inventor(s): Address for Service: Thris docu-ment contains the amendments made under Section 49 and is correct for printing. GUY PETER GARDNER AND ROBERT DAVID
EATON
G.R. CULLEN COMPANY, Patent Trade Mark Attorneys, Dalgety House, 79 Eagle Street, Brisbane, Qld, 4000, Australia.
COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: a4t 4 REINFORCED LAMINATED TIMBER The following statement is a full description of the invention including the best method of performing it known to us -2 THIS INVENTION relates to composite structural members and is particularly concerned with laminated structural timber having reinforcing elements.
Laminated timber is widely used in residential and light engineering structures in situations where large beam depths are required, such as long span openings in houses.
Large section timber is becoming more expensive and more ae difficult to obtain, and manufacturers have found it necessary to laminate smaller sections together to make the larger section sizes more readily available. Timber, in general, has a pleasing aesthetic effect and therefore in many architectural applications laminated beams are used, and are left exposed. However, bare timber is relatively weak i both in strength and stiffness when compared with other building materials such as steel.
Laminating a number of smaller sections of timber together to make a larger member decreases the possibility of inherent weaknesses due to natural wood defects and also I decreases the disparity in the strength of structural timber members because laminating effectively averages the varying properties of the timber used, But when joining shorter sections of timber together to make a single lamination, the I joins themselves become a point of inherent weakness.
Disparity of strength still exists though, and therefore the structural members must be carefully graded, and any member having an apparent weakness, either due to 4 i X~ ILr^~.rr r Li; -i i Il.rCI-- IIC- natural wood defects or at the joins within the individual laminations, must be rejected or downgraded which, of course, decreases their commercial value substantially. Also the load carrying capacity of a timber member will, by the very nature of the material, vary due to such factors as humidity and temperature changes, degree of seasoning, moisture i content, and load duration; and making allowances for these i variations can downgrade the design loads and deflections of the member compared to a member which is not dependent on these factors.
A further weakness of timber when used as a structural member is the effect of timber relaxation when subjected to long duration loads. Most structural beams in house construction are designed for long duration load and because of timber relaxation, the stiffness of the beam is approximately halved, Another disadvantage of timber as a structural member is its failure mode. When the ultimate load of the I beam is reached, the extreme fibres of timber on the tension S 20 face split and then the beam can no longer sustain the applied load. The failure is a catastrophic collapse and therefore undesirable in construction.
Previous attempts to increase the strength and stiffness of structural timber members have been made. In U.S. Patent No. 3251162 a series of rods or cables pass through a laminated beam and are connected to tensioning 4 plates and bolts at either end. However, the manufacire of products where one or more elements must be held under tension is inherently expensive. It also prohibits cutting the member into smaller lengths.
In Australian Patent Specification No. 33,433/84, steel strips are connected to the outer faces of a timber member to increase the strength and stiffness. However, the external application of the reinforcing sections detract from 9, the aesthetic appeal of the members and also cause difficulty 1 0 in ccnnecting the member. The method of bonding the strips to the timber has the adverse effect of severely damaging the extreme timber fibers which are crucial in transferring load into the strips and in taking load themselves.
United States Patent Specification No. 4,615,163 discloses a wooden beam reinforced with a glass fibre polyester rod. The rod is located within a groove formed on the surface of the beam or in a groove formed on the surface of a bottom lamination between adjacent laminations in a laminated beam. The rod is bound to the timber by a resin based adhesive. The disadvantage of these structures is that the bond between the rod and the timber is not particularly strong and the increase in strength which is obtained is so small as to not be economically viable. Furthermore, in the case of laminated beams, it is more economical to use additional laminations in the construction to gain the same increase in strength and stiffness, rather than use such reinforcements.
It is therefore an object of the present invention to provide a laminated structural timber member which is reinforced in such a way as to obviate or at least minimise the aforementioned disadvantages of known structural timber members.
According to one aspect of the present invention there is provided a laminated structural timber member comprising a plurality of longitudinally extending wooden laminations bonded together by a resin adhesive and reinforced by at least two longitudinally extending solid metal rods each having an integral spiral winding projecting outwaidly from its' surface, said metal rods being contained in grooves formed in or between the laminations and being bonded to the one or two laminations by said resin adhesive, one at a location between the longitudinal axis of the timber member and a longitudinal edge of the timber member, and the other at a location between the longitudinal axis of the timber member and the other longitudinal edge of the timber member, said spiral windings being such that they do not penetrate the wooden laminations but enable a keying effect l to be produced between the metal rods, said resin adhesive S0 and said laminations.
0 0 The use of metal rods for reinforcement 0 A significantly increases the strength characteristics of the laminated timber member and the spiral windings on the rods
A
6 A L t 6 ensure that the metal rods are firmly keyed to the adhesive and to the wooden laminations.
jI The location of the metal rods within the timber i member enables maximum load carrying capacity and red-oLtion I 5 in deflection under a given load. The importance of the Slocation of the metal rods can be demonstrated by reference to a 315 mm deep by 70 mm wide laminated timber beam of structural grade F22, with a 28 mm diameter high strength steel reirforcing rod placed at the centre of the beam. The increase in the strength and stiffness of the beam is only Placing the rod close to the top or bottom of the beam increases the strength of the beam by approximately 23% and the stiffness by approximately 48%. However, placing 28 mm diameter rods both close to the top and bottom of the beam increases the strength and stiffness by a significant 128%.
Placing two reinforcing rods at each the top and bottom, one on top of the other, increases the strength and stiffness by 192%. Two smaller rods side by side are only more effective if the sum of their areas is greater than the 28 mm rod.
The spirally wound metal rod may be fabricated from any metal suitable for the particular application to which S. the laminated timber member is to be put. Examples of suitable metals include aluminium, iron, steel, and various alloys. The most preferred metal is high strength reinforcement steel.
The preferred profile for metal reinforcing rods is t i 4 4 L6Z__ 7 that complying with the Australian Standard, Steel Reinforcing Bars for Concrete, AS1302 grade 410Y.
The maximum section of the reinforcing rod that can be used is dependent upon the shear stresses developed in the adjacent timber at the sides of the deformed metal bar.
These shear stresses must comply with Australian Standard, Timber Engineering Code AS1720. Smaller sections still have significant increases in strength and stiffness and may therefore be used for economic or production reaso 8s. The minimum section size that can be used is such that the increase in strength and stiffness is sufficient to economically justify its use. The maximum and minimum sizes of high strength deformed steel reinforcing rods produced are 36 mm diameter and 12 mm diameter respectively and are available in increments of 4 mm.
f High strength deformed steel reinforcing rods are preferred rods because they have a deformation pattern that is used to physically key the bar in place within an adhesive and allows the transfer of load without needing or relying 0 I upon adhesive-steel adhesion. To ensure the physical keying of the deformations, the adhesive used should preferably be n- o non-shrinking.
o'a The deformed metal rods will generally extend over 0 the entire length of the timber member for maximum effect.
However, this is not essential since some applications may require lesser strength characteristics. It is, iII.
I
~ill i.llll4l(.. 11_ ;I-.I--YI~Lil 8 nevertheless, generally envisaged that the lower limit of extension will be approximately 10%. The preferred extension will lie within the range of 70% to 100% of the length of the timber member.
Preferably, the metal rod reinforcements are located within planed, routed or milled grooves between laminations, close to the top and bottom longitudinal edges of the timber member.
The resin adhesive will typically be of the type commonly used in the manufacture of laminated beams; that is, one that complies with the Australian Standard, Glue Laminated Structural Timber Code, AS 1328, such as Epiglass Hi Tech HT 9000.
The timber member will generally be a beam, but it could also be a post, rafter, joist or like structural component which are all well known to the skilled addressee.
In a further aspect of the present invention, the aforementioned laminated structural timber member is adapted to enable attachment to other structural members, being either other laminated timber members or concrete or steel members, By "adapted" is meant one of the following: (i) S that the reinforcing metal rod is restricted to such a length a that a groove is left in one or both ends of the beam to enable a connecting rod to be inserted therein; (ii) that 0 o a one or more additional grooves is formed in at least one end of the beam to enable one or more connecting rod- to be 46S0 I 0 4F I I -i 9 inserted therein, or (iii) that at least one end of one or more of the reinforcing rods is routed around to enable attachment of the rod or rods to a mechanical coupler.
According to another aspect of the present invention, there is provided a method of making a laminated structural timber member of the aforementioned type, which method comprises the steps of: forming a longitudinal groove in one lamination element or two lamination elements which are adapted to be bonded together; (ii) applying resin adhesive to the groove of one or both lamination elements; (iii) placing a longitudinally extending metal rod in the groove of one lamination element containing resin adhesive, said metal rod having an integral spiral winding projecting outwardly from it's surface; o (iv) placing the other grooved lamination Selement, or a different non-grooved lamination element, over the lamination element containing the metal rod, either with or without the addition of further resin adhesive; adding further laminations, one or more of i which a;e produced according to steps (iii) above; and o (iv) curing the resin adhesive.
The reinforced laminated structural timber member 00 2' according to the present invention enables the timber member to increase its load carrying capacity and reduce its i i._il I i. i i i deflection under a given load, in a very economical manner.
The method of reinforcement overcomes inherent weaknesses resulting from either natural wood defects or joints between timber pieces within a lamination. It enables uniformity and reproducibility of end product. It reduces the effect of timber relaxation while subjected to long duration loads, i.e. to increase the long term stiffness of the timber.
When a reinforcing metal rod is located close to the top and bottom longitudinal edges of a structural timber element such as a beam, upon the beam reaching its ultimate capacity under an applied load and tensile cracks begin appearing the timber fibres across the tension face of the beam, the reinforcing metal rods will themselves not be loaded to their ultimate capacity, This allows cracks, that is, areas of severe distress, to be observed prior to a catastrophic collapse, Preferred embodiments of the invention will now be described with reference to the accompanying drawings, in which:- Fig, 1 is a sectional end view showing a laminated timber beam and the preferred positions and placement of the So; reinforcing rods; Fig. 2 is a sectional end view of a laminated timber box beam and the preferred positions and placement of the reinforcing rods; 4 4 11 Fig. 3 is an enlarged side elevational view of a steel reinforcing rod; Fig. 4 is a cross-section of the rod depicted in Fig, 3; Fig, 5 is a sectional side view of a laminated Stimber beam as shown in Fig. 1; Fig. 6 is a sectional side view of a beam to beam pin splice using a dowelling technique; Fig. 7 is a sectional side view of a beam to beam moment splice using an overlap technique; Fig. 8 is a sectional side view of a se ondary beam to main beam pin connection using a dowelling technique; Fig. 9 is a sectional side view of a secondary beam to main beam moment connection using a mechanical anchoring technique; Fig. 10 is a sectional view of a continuous secondary beam to main beam pin connection using a dowelling technique; Fig. 11 is a sectional side view of a beam to column pin connection using dowelling technique; Fig. 12 is a sectional side view of a beam to I column moment connection using a mechanical anchoring j technique; Fig. 13 is a sectional side view of a beam to column moment connection using an overlap technique; *a a 24 0 4 4 -iiii -_r-iii-i Ill- r 12 Fig. 14 is a sectional side vs -w ,f a beam to column moment connection using a mechanical anchoring technique; Fig. 15 is a sectional side view of a beam ridge pin connection using a dowelling technique; Fig. 16 is a sectional side view of a beam ridge moment connection using an overlap technique; Fig. 17 is a sectional side view of a column footing pin connection using a dowelling technique; and Fig. 18 is a sectional side view of a column footing moment connection using a mechanical anchoring technique, Fig. 1 illustrates a timber beam comprising a plurality of wooden laminations 1 with a high strength deformed steel reinforcing rod 4 located in the lower and upper longitudinal sections of the beam adjacent to the edges thereof. An enlarged view of this rod is depicted in Figs.
3 and 4.
The reinforcing rods 4 are located in grooves 3 that are milled, planed or routed in the timber to suit *ia, accept the rods. The grooves are preferably positioned such that the timber thickness covering the reinforcing rod (refer Fig, 1 dimension is approximately equal to the covering thickness to the sides of the beam (refer Fig. 1 dimension It is preferable that the grooves be as close fitting as possible to the size and shape of the reinforcing rod, and therefore, it is preferable to position the grooves 3 between .i i i 13 therefore, it is preferable to position the grooves 3 between laminations 2.
The reinforcing rods are fixed into the grooves with a resin-based adhesive 5 that complies with Australian Standards, Glue Laminated Structural Timber Code AS 1328, and therefore bonds to the surrounding timber such that the resulting bond is stronger in shear, tension and bearing than the timber, Table I summarises the increases in strength and stiffness using various preferred arrangements. The table j shows the ranges of increase in strength and stiffness in percent, for beams reinforced with deformed steel reinforcing bars, placed in the outer laminations, as shown in Fig. 1, calculated over a range of beam widths and depths that are commercially available, and for differing timber structural grades, i TABLE I 20 Steel Reinforcing 36 32 28 24 20 16 Bar Diameters (mm) Range of beam 110-135 90-110 90-70 70-60 60-40 widths (mm) Range of beam 155-600 155-600 120-600 120-600 120-315 120-315 depths (mm) TIMBER STRUCTURAL
GRADE
F27 65-135 60-130 60-105 55-100 60-105 6065 F22 75-155 70-150 70-120 65-115 70-120 65-80 F14 95-200 90-190 85-155 80-145 90-155 85-100 F8 130-280 125-265 120-215 110-200 125-210 120-135 i i 14 This table clearly demonstrates the substantial increase in strength obtained by reinforcing timber beams according to the present invention, Referring to Fig. 2, there is illustrated a laminated timber box beam 7 comprising timber laminations 2 along each longitudinal edge, thin plywood webs 6 formed along each face of the beam and deformed steel reinforcing rod 4 located in grooves 3 formed between the timber laminations 2.
Similar increases in strength and stiffness are exhibited by this structure as are exhibited by the structure described with reference to Fig. 1.
In beams reinforced in accordance with the above two bmbodiments, the reinforcing rods take a far greater proportion of the applied load than the timber in the beams.
This means that the load carrying capacity of the member will vary significantly less due to atmospheric and timber property changes, which, of course, do not affect the reinforcing rods. This means that the occurrence of inherent weaknesses and the disparity of timber strength also have a much reduced effect on the member's strength.
Fig. 5 illustrates a laminated beam with reinforcing rods 4 extending approximately 90% of the length of the beam. Otherwise, the construction is substantially the same as illustrated in Fig. I and like reference numerals refer to like parts. This depicted arrangement lies within a fr3 3 18 925/88 -T4 the most preferred range wherein the reinforcing rods extend to 100% of the full length of the beam.
It has been calculated that an increase in the length of the reinforcing rod from 40% to 70% of the length of the beam may increase the stiffness of the beam from approximately 50% to 80%, while the increase in the length from 90% to 100% increases the stiffness by a further Maximum stiffness is thus obtained from th section extending the full length of the beam, and extensions over 90% are minimal.
Figgs. 6 18 illustrate embodiments according to the further aspect of the invention which relates to attachment of laminated structural timber elements to other structural members. The method of attachment may be achieved in the following preferred ways.
The first method is a dowelling technique, making use of the empty grooves at the end of beams in which the reinforcing bars do not extend the full length of the beam, and inserting portions of reinforcing bars or sections 9, for connecting purposes into these grooves and butting them up against the in situ reinforcing bars or sections 4. The portions are fixed in place by injecting a resin-based adhesive, similar to that used in fixing the reinforcing sections in the beam, until the grooves are fully filled, see Figs. 6, 8, 10, 11, 15 and 17. In these figures, like reference numerals to those of Figs. 1 3, refer to like 16 integers in those drawings.
The second preferred jointing method is an overlapping technique made by planing, milling, routing or drilling other grooves adjacent to the grooves in which the reinforcing sections are fixed, and inserting portions of reinforcing bars or sections 9 for connecting purposes, into these grooves. The portions overlap the in situ reinforcing bars or sections 4 sufficiently to transfer loads as dictated So a by Australian Standards Timber Engineering Code AS1720, and 10 are fixed in place by injecting a resin-based adhesive, S° similar to that used in fixing the reinforcing sections in the beam, until the grooves are fully filled, see Figs. 7, 13 and 16.
The third preferred method is a mechanical anchoring technique effected by using high strength steel reinforcing bars 4 and either threading the ends of the bars and using mechanical couplers or using mechanical splices routing the groove around the ends of the bars to accommodate the larger outer diameter of a mechanical coupler 20 or splice; placing the bar complete with the mechanical coupler or splice in the groove; and fixing the bars in place. Bolts or other threaded sections 11 can be screwed into the coupler or splice to make the joint, see Figs. 9, 12, 14 and 18.
In the preferred method of manufacture, a groove is formed in the timber as the lamination passes thzough a J r I. Il.ii.. i C 31
I
17 moulder which dresses the lamination to the required thickness. The resin-based adhesive, in the case of the high strength deformed steel reinforcing bar, is placed in every groove as the lamination is passed through the glue spreader that applies the laminating glue to the dressed surfaces.
The reinforcing section is placed in the beam as the beam laminations are assembled in a conventional manner. The structure is then cured to produce the desired reinforced l laminated structural member.
10 Load tests conducted on a number of members constructed in accordance with the invention disclosed herein provide evidence of its value and effectiveness. The beams were tested using a two-point loading configuration, and tested in accordance with Australian Standards, Timber Engineering Code AS1720 as prototype tests and were therefore tested to the required equivalent test loads (ETL). The results of a typical teOt are tabulated in Table II together with theoretical valuos of both the unreinforced and a 4 reinforced beam, The member, whose results are shown in 0 Table II, is a six metre long beam, 295 mm deep by 85 mm wide, of structural timber grade F8, Young's Modules of 9975 MPa, with 24 mm diameter high strength deformed steel reinforcing bars inserted between the outer top and bottom laminations with the bars' centres 35 mm from the outer faces of the beam. The bars extend the full length of the beam and are fixed in place with a resin-based adhesive, Epiglass
V
I xi-..i^ir i.inil~ri~ 18 Epiglue. The table shows that the theoretical and experimental values are similar, while the unreinforced and reinforced theoretical values highlight the 125% increase in strength and stiffness obtained by reinforcing the beam in the manner described.
TABLE II LOAD DEFLECTION AT MID POINT OF BEAM (mm) (TONNES) REINFORCED BEAM UNREINFORCED EXPERIMENTAL THEORETICAL THEORETICAL .0 0 0 0 0 0.4 3.04 3.68 8.28 0.8 6.61 7.36 16.57 1.2 10.34 11.03 24.86 1.6 14.11 14.71 33.14 2.0 17.79 18.39 41.43 2.4 21.66 22.07 49.71 2.8 25.49 25.74 58.00 3.2 29.40 29.42 66.28 3.6 33.25 33.10 74.57 0 4.0 37.16 36.78 82.86 4.4 41.08 40.46 91.14 4.8 45.09 44.14 99.43 5.2 48.71 47.81 107.71 5.6 52.68 51.49 116.00 A number of beams were subjected to long term loads equal to their design loads to investigate timber 4 I 19 relaxation. The results of timber relaxation tests for the beam described above are tabulated in Table III. The results show that there is a significant increase in the long term stiffness of laminated timber when reinforced in accordance with the invention disclosed herein. Whereas in natural timber a factor of 2.0 is applied to account for timber relaxation, the results of the tests on the reinforced laminated timber beams indicate that a factor very close to can be used.
A number of beams have also been tested to failure. The tests show that with the application of loads i which cause tensile cracks to occur on the tension face of I the beams, the beams were still able to carry the applied load, proving that the invention as disclosed herein ensures against catastrophic collapse. The results of the test to failure of the beam described above are tabulated in Table IV, and shows the ability of the beam to carry the load after the splitting of the timber fibers on the tension face, TABLE III t j~ TIME DEFLECTION INCREASE IN DEFLECTION (HOURS) (mm) (nmm) 0 25.55 0 25 25.75 0.20 25.75 0.20 125 25.75 0.20 325 1 25.85 0.30 375 25.90 0.35 500 25.90 0.35 550 25.95 0.40 675 25.80 0.25 725 25.80 0.25 900 25.90 0.35 TABLE IV LOAD DEFLECTION DESCRIPTION/REMARKS (TONNES) (mm) 0 0 .815 9.75 1.733 18.55 2.752 27.50 Design Load 3.700 35.90 4.587 44.00 5.627 53.35 Prototype ETL 6.575 62.50 7.492 71.45 Tensile Cracks 8.410 84.75 9.378 101.10 Ruptured Load 5.060 143.80 Load carrying capacity of ruptured section Whilst the above has been given by way of i. _i y tl I I- -K i i 21 illustrative example of the invention, many modifications and variations may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein defined in the following claims.
a

Claims (16)

1. A laminated structural timber member comprising a plurality of longitudinally extending wooden laminations bonded together by a resin adhesive and reinforced by at least two longitudinally extending solid metal rods each having an integral spiral winding projecting outwardly from its' surface, said metal rods being contained in grooves formed in or between the laminations and being bonded to the one or two laminations by said resin adhesive, one at a location between the longitudinal axis of the timber member and a longitudinal edge of the timber member, and the other at a location between the longitudinal axis of the timber Smember and the other longitudinal edge of the timber member, said spiral windings being such that they do not penetrate oo the wooden laminations but enable a keying effect to be produced between the metal rods, said resin adhesive and said laminations.
2. A laminated structural timber member as claimed in claim 1 and including one or more additional longitudinally extending solid metal rods each having an integral spiral winding projecting outwardly from its' surface, said additional rods being contained in grooves formed in or S* between the laminations and being bonded to one or more of the laminations by said resin adhesive.
3. A laminated structural timber member as claimed in claim 1 or claim 2, wherein said metal rods extend from i i I .L to 100% of the length of the timber member.
4. A laminated structural timber member as claimed in claim 3 wherein said metal rods extend from 70% to 100% of the length of the timber member.
A laminated structural timber member as claimed in any one of the preceding claims, wherein the metal rods are located in the outermost laminations of the timber member,
6, A laminated structural timber member as claimed in any one of the preceding claims wherein said metal rods are steel reinforcing rods, i
7. A laminated structural timber member as claimed in any one of the preceding claims wherein said timber member is a timber beam. B
8. A laminated structural timber member as claimed in any one of the preceding claims which is "adapted" (as herein defined) to enable attachment to other structu 1 members.
9, A laminated structural timber member as claimed in Sclaim 8 wherein one or more additional grooves is formed in at least one end of the beam to enable one or more connecting ods to be inserted therein. SO
10, A laminated structural timber member as claimed in j claim 8 wherein at least one end of one or more of the metal S° rods is routed around to enable attachment of the rod or rods to a mechanical coupler, 1'
11, A method of making a reinforced laminated structural timber member which comprises the steps oft i _i ii. _i 24 forming a longitudinal groove in one lamination element or two lamination elements which are adapted to be bonded together; (ii) applying resin adhesive to the groove of one or both lamination elements; (iii) placing a longitudinally extending metal rod in the groove of one lamination element containing resin adhesive, said metal rod having an integral spiral winding projecting outwardly from it's surface; (iv) placing the other grooved lamination element, or a different non-grooved lamination element, over the lamination element containing the metal rod, either with or without the addition of further resin adhesive; adding further laminations, one or more of which are produced according to steps (iii) above; and (iv) curing the resin adhesive,
12. A method of making a laminated structural timber member as defined in claim 11 which results in a product as defined in any one of claims 2 7
13, A reinforced laminated structural timber member substantially as herein described with reference to any one of the accompanying drawings.
14. A method of making a reinforced laminated structural timber member substantially as herein described I,,r with reference to the accompanying drawings.
15. A plurality of reinforced laminated structural i .i I .r r_. timber members connected together substantially as herein described with reference to any one of Figs. 6, 7, 11, 12, 13, 14, 15 or 16 of the accompanying drawings.
16. A reinforced laminated structural timber member adapted, as herein defined, for connection to another structural member substantially as herein described with reference to any one of Figs. 8, 9, 10, 17 or 18 of the accompanying drawings. DATED this 27th day of March 1990 GUY PETER GARDNER and ROBERT DAVID EATON By their Patent Attorneys G.R. CULLEN CO. S 0 0 00 J 0 a I *j e-* t e S S i ,1 .i i i
AU18925/88A 1987-11-11 1988-07-11 Reinforced laminated timber Expired AU598684B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
AU18925/88A AU598684B2 (en) 1987-11-11 1988-07-11 Reinforced laminated timber
CA000582611A CA1307731C (en) 1987-11-11 1988-11-09 Reinforced laminated timber
NZ226918A NZ226918A (en) 1987-11-11 1988-11-09 Metal rod reinforced laminated timbers
JP88284826A JPH01287354A (en) 1987-11-11 1988-11-10 Reinforced laminated wood

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
AUPI5351 1987-11-11
AUPI535187 1987-11-11
AU18925/88A AU598684B2 (en) 1987-11-11 1988-07-11 Reinforced laminated timber

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AU1892588A AU1892588A (en) 1989-05-11
AU598684B2 true AU598684B2 (en) 1990-06-28

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AU (1) AU598684B2 (en)
CA (1) CA1307731C (en)
NZ (1) NZ226918A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2764622A1 (en) * 1997-06-17 1998-12-18 Paul Henri Mathis Vegetable fibre base composite beam used in constructions, especially of support structures
EP0915213A3 (en) * 1997-11-04 2000-10-18 Konstruktion-Holz-Werk Seubert KHW GmbH & Co. KG Wooden building element and its manufacturing method

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JPH0494403U (en) * 1990-12-28 1992-08-17
JP3346487B2 (en) * 1993-04-13 2002-11-18 住友林業株式会社 Composite beam
US7726094B2 (en) 1997-01-17 2010-06-01 Induo Gesellschaft Zur Verwertung Von Schutzrechten Mbh & Co. Kg Supporting structure and its structural members
JP5801129B2 (en) * 2011-07-27 2015-10-28 小松精練株式会社 Method of joining wooden members
EP3366855B1 (en) * 2017-02-24 2020-04-01 Knapp GmbH Connector, support and device for coupling vertical components
CN112502278B (en) * 2020-11-03 2022-05-17 濮阳职业技术学院 A assembled connected node for large-span

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AU570331B2 (en) * 1984-06-22 1988-03-10 Arne Engebretsen Reinforced/strengthened laminated wood beam

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AU570331B2 (en) * 1984-06-22 1988-03-10 Arne Engebretsen Reinforced/strengthened laminated wood beam

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2764622A1 (en) * 1997-06-17 1998-12-18 Paul Henri Mathis Vegetable fibre base composite beam used in constructions, especially of support structures
EP0915213A3 (en) * 1997-11-04 2000-10-18 Konstruktion-Holz-Werk Seubert KHW GmbH & Co. KG Wooden building element and its manufacturing method

Also Published As

Publication number Publication date
NZ226918A (en) 1991-06-25
CA1307731C (en) 1992-09-22
JPH01287354A (en) 1989-11-20
AU1892588A (en) 1989-05-11

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