BEAM AND JOIST ASSEMBLY

Abstract

The present invention is an I beam including a web, a top flange and a bottom flange. The flanges are parallel with the web extending therebetween so as to form spaces, at both sides of the web. Notches are formed in the top and bottom flanges of a joist of a height for fitment into the space of beam. A plate with at least four holes equi-spaced top and bottom is welded to each end of the stock length supplied beam, perpendicular to the web. The invention includes the method for providing a beam to beam connection, wherein the top and bottom flanges of beams are notched such that a first end is disposed between the top and bottom flanges of the first beam, and wherein the second beam web includes a connection plate to attach to the first beam web via fasteners.

Claims

1. A beam and joist assembly, comprising: an I cross-section beam having a top flange and a bottom flange with a web extending therebetween, the beam having a beam depth extending from a top surface of the top flange to a bottom surface of the bottom flange, and a joist having a top surface and a bottom surface, the joist having a joist height extending from the top surface to the bottom surface thereof, wherein the beam depth is the same as the joist height.

2. The assembly of claim 1, wherein a notch is formed in each of the top and bottom surfaces of the joist, wherein the first end of the joist is disposed between the top and bottom flanges of the beam such that the top surfaces of the beam and the joist are level, and the lower surfaces of the beam and the joist are also level.

3. The assembly of claim 2, wherein the joist is made from timber, and the beam has a minimum beam flange width related to the length of the timber joist.

4-5. (canceled)

6. The assembly of claim 2, wherein the top and bottom flanges of the beam have a maximum flange thickness related to the maximum depth of the notches to be formed in the top and bottom flanges in the first end of the joist.

7. (canceled)

8. The assembly of claim 1, wherein the joist is an I cross-section joist having a top flange and a bottom flange with a web extending therebetween.

9. The assembly of claim 1, wherein a notch is formed in each of the top and bottom flanges in a first end of the joist, wherein the first end of the joist is disposed between the top and bottom flanges of the beam such that the top surfaces of the beam and joist top flanges are level, and the lower surfaces of the beam and joist bottom flanges are also level.

10-12. (canceled)

13. The assembly of claim 1, further comprising: I cross-section beams having a top flange and a bottom flange with a web extending therebetween, the beams each having a beam depth extending from a top surface of the top flange to a bottom surface of the bottom flange, wherein the beam depths vary in the set, and the top and bottom flanges of the beams in the set each have the same thickness.

14-15. (canceled)

16. A steel beam to steel beam connection assembly, comprising: a first I cross-section beam having a top flange and a bottom flange with a web extending therebetween, and a second I cross-section beam having a top flange and a bottom flange with a web extending therebetween, the second beam disposed perpendicular to the first beam, wherein the top and bottom flanges of a first end of the second beam are notched such that the first end is disposed between the top and bottom flanges of the first beam, wherein the second beam web comprises a connection plate at the first end to attach to the first beam web via fasteners.

17. The connection assembly of claim 17, wherein the second beam comprises another connection plate at a second end thereof.

18-19. (canceled)

20. The connection assembly of claim 16, wherein the connection plate comprises four holes which are symmetrical around both the vertical and horizontal axes of the beam

21. A method of construction, the method comprising: providing an I cross-section beam having a top flange and a bottom flange with a web extending therebetween, providing an I cross-section joist having a top and bottom flanges with a web extending therebetween, wherein the beam depth and the joist height are the same.

22. The method of claim 21, further comprising forming a notch in each of the top and bottom flanges in a first end of the joist, and inserting the first end of the joist between the top and bottom flanges of the beam such that the top surfaces of the beam and joist top flanges are level, and the lower surfaces of the beam and joist bottom flanges are also level.

23. The method of construction of claim 21, the method comprising providing an I cross-section beam having a top flange and a bottom flange with a web extending therebetween, the beam having a beam depth extending from a top surface of the top flange to a bottom surface of the bottom flange, providing an I cross-section joist having a top flange and a bottom flange with a web extending therebetween, the joist having a joist height extending from a top surface of the top flange to a bottom surface of the bottom flange, wherein the beam depth and the joist height are the same.

24. (canceled)

25. The method of construction of claim 21, the method comprising: providing I cross-section beams having a top flange and a bottom flange with a web extending therebetween, the beams each having a beam depth extending from a top surface of the top flange to a bottom surface of the bottom flange, wherein the beam depths vary, and the top and bottom flanges of the beams each have the same thickness.

26-27. (canceled)

28. The method of claim 21, further comprising: providing a beam to beam connection comprising: a first I cross-section beam having a top flange and a bottom flange with a web extending therebetween, a second I cross-section beam having a top flange and a bottom flange with a web extending therebetween, the second beam disposed perpendicular to the first beam, wherein the top and bottom flanges of a first end of the second beam are notched such that the first end is disposed between the top and bottom flanges of the first beam, wherein the second beam web comprises a connection plate to attach to the first beam web via fasteners.

29-33. (canceled)

34. The assembly of claim 1, further comprising: a timber joist having a joist height extending from a top surface to a bottom surface thereof, wherein the beam depth and the joist height are the same, wherein a notch is formed in each of the top and bottom surfaces in a first end of the joist, the notches having a depth substantially equal to a thickness of the top and bottom flanges, wherein the first end of the joist is to be disposed in use between the top and bottom flanges of the beam such that the top surfaces of the beam and the joist are level, and the lower surfaces of the beam and the joist bottom flanges are also level.

35. The assembly of claim 34 wherein a notch is formed in each of the top and bottom surfaces in a second end of the joist, the notches having a depth substantially equal to a thickness of the top and bottom flanges.

36. The assembly of claim 34 wherein the timber joist is an I cross-section joist having a top flange and a bottom flange with a web extending therebetween, wherein the notches are formed in the top and bottom flanges.

37. A method of construction, the method comprising: using the beam and the joist of claim 34; supplying the timber joist to site with the notches at the first end pre-cut prior to delivery to site; and disposing the first end of the joist between the top and bottom flanges of the beam.

38. A method of construction, the method comprising: using the beam and joist of claim 35; supplying the timber joist to site with the notches at the first and second ends pre-cut prior to delivery to site, supplying the timber joists to site pre notched at one or two ends and the joist cut to length, disposing the first end of the joist between the top and bottom flanges of a first beam, and disposing the second end of the joist between the top and bottom flanges of a second beam.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0103] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings.

[0104] FIG. 1 (a-c) show perspective views of prior art examples of conventional timber joist to steel beam connection mounting methods.

[0105] FIG. 2 is a cross-sectional view of a beam according to a preferred embodiment of the present invention.

[0106] FIG. 3 shows a sectional view of a single sided connection between a timber joist and the beam showing notching to the top and bottom flanges of the timber joist.

[0107] FIG. 4 is a perspective view of an end of a beam as in FIG. 2, with the beam flanges being notched at the ends thereof and a connection plate welded to the web.

[0108] FIG. 5 shows a sectional view of the beam as in FIG. 4 connected to another beam via the connection plate.

[0109] FIG. 6 shows a perspective view of the beam as in FIG. 4 with a connection plate welded to each end.

[0110] FIG. 7 (a-b) show a perspective view (a) and an end elevation view (b) respectively of a beam according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0111] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

[0112] FIG. 2 shows a cross-section of a beam 10 according to a preferred embodiment of the present invention. The beam 10 is an I beam and comprises a web 11, a top flange 12 and a bottom flange 13. The flanges 12 and 13 are parallel with the web 11 extending therebetween. The flanges 12 and 13 and the web 11 form spaces 19, at both sides of the web 11.

[0113] The web has a web thickness 14 and the flanges both have a flange thickness 15. The beam 10 has a depth (height) 16 and flanges have a width 17.

[0114] As shown in FIG. 3, one application of the beam 10 is for mounting of a timber I joist 20 perpendicularly thereto, with the end of the joist 20 received in one of the spaces 19. The ends of a respective joist 20 can be received in the spaces 19, with the joists 20 extending in opposite directions. The timber joist 20 is also an I beam and comprises a web 21, a top flange 22 and a bottom flange 23.

[0115] The beam depth 16 is equal to the height 26 of the joist 20. The flange thickness 15 is less than the maximum notching height of the flanges 22 and 23 of the joist 20. This maximum notching height is 12 mm to suit timber joists (currently in use in Australia however the flange thickness is adjusted to suit any timber joist which has a maximum notch depth). The beam flange width 17 is the minimum width to support the notched timber I joist 20 in the spaces 19 on each side of the beam 10.

[0116] The single sided timber joist 20 connection to the steel beam 10 shows notches 31 in the top and bottom flanges 22 and 23 of the joist 20 of a height for fitment into the space 19 of beam 10. The top surfaces 34 of the beam and joist top flanges 12 and 22 are level, and the lower surfaces 35 of the beam and joist bottom flanges 13 and 23 are also level.

[0117] The present invention comprises an I beam with an overall depth corresponding to the overall depth of timber I joists which are used in the construction of timber floors.

[0118] The depth sizes of the I joists used in Australia are 200 mm, 240 mm, 255 mm, 300 mm, 360 mm and 400 mm depth. The most commonly used I joists, being the 240 mm and 300 mm depths, come in a number of different timber flange sizes (widths) enabling larger spanning capacities.

[0119] The timber joists 20 are fitted to a structural steel beam 10 by notching 31 its bottom flange 23 to a depth of the steel beam bottom flange 13, but no greater than the allowable design notch depth (12 mm) to maintain structural capacity of the joists 20. The length of the notch 31 can be no shorter than the minimum that will maintain structural adequacy of the joist.

[0120] The timber joists 20 are manufactured off site and provided in predetermined depths and lengths, they are pre-notched in the top and bottom flanges 22 and 23 at each end or on one end only of the timber I joists, transported to the site in cut to length and ready to use to construct the floor structure.

[0121] The steel beam 10 in the invention incorporates a flange thickness 15 which is common to the beams in a beam group of the same depth 16. For example, the beam flange width 17 for the 240 mm depth beams can be 125 mm and 200 mm wide. In the 300 mm depth beams, the flange widths are 125 and 200 mm. The standardisation of flange width in a beam group means that carpenters can visually size the beam width and cut their joists to length.

[0122] In the prior art, the flange thickness can differ between beam groups of different steel beam depths due to maximising steel beam material efficiencies, however in the preferred form of the invention, the flange thickness is the same for all steel beam depths.

[0123] The flange thickness is the same for all beam depths, and the flange thickness is equal to or less than the maximum notch depth of the timber joists. The beam capacity in each group comprising the same depth is increased by widening the top and bottom flange width 17.

[0124] The flange 12/13 with can be widened to suit a design capacity required for a beam in any group with the same depth. In the preferred form, the flange widths 17 are the same for each beam grouping.

[0125] In another embodiment of the preferred form of the invention, the minimum beam flange width 17 is twice the minimum bearing length for the notch 31 in the timber joists 20 plus twice the root radius between the flange 12/13 and the web 11 and the beam web thickness 14 and 28 mm clearance. Using Australian joists and the preferred beam design, this equates to 245 mm (minimum bearing length) plus 26 mm (radius 6 mm on the join between the web and the flange each side) plus 7 mm (web thickness) and 210 mm (clearance) which sums to 124 mm. Hence the minimum flange width 17 in the beams 10 of this preferred embodiment is nominally 125 mm.

[0126] The maximum flange width is designed to support the external brick veneer, nominally 110 mm thick and the internal (normally) load bearing timber wall which is nominally and usually 90 mm thick. The brick cladding is allowed to overhang the steel beam by 25 mm, and given a brick veneer cladding and internal wall with cavity between them is nominally 250 mm thick, the generally accepted flange width to support the wall is 200 mm.

[0127] As shown in FIGS. 4 to 6, another embodiment is the optimisation of standard beam lengths supplied to fabricators. The beam length is sized to suit production so that at least two beams are cut optimally from a standard length.

[0128] Generally, one end of a beam 10b is fixed to another beam 10 using a cleat and bolt connection. So instead of welding a cleat to a beam to form a connection during manufacturing, a standard sized plate 30 with at least four holes 32 equi-spaced top and bottom is welded to each end 33 of the stock length supplied beam, perpendicular to the web 11.

[0129] The four holes 32 in the connection plate 30 are symmetrical around both the vertical and horizontal axes of the beam, which means the beam is not handed in regard to the connection plate.

[0130] Generally only 2 bolts are required in most beam to beam connections. So in this connection, to maintain the connection loading directly into the beam web 11 attached to the bracket plate 30, bolts have to be installed across the diagonal. So only two diagonally opposite holes need to be drilled in the mating beam web, this saves time labor and obviously two bolts and labor on site.

[0131] The benefit of this bolting arrangement is that the loading through the connection is co-linear with the webs 11, and the mating beam diagonal holes do not make the beam handed, they are equi-spaced about the centerline of the connection, and regardless in which direction the holes are made across the diagonal, there will always be a pair of diagonally opposed holes in the 4 holes connection plate 30 to complete the connection. This is far superior to a plate and web connection because the web of the mating beam can be connected to the plate either side of the plate, making the beam location either correct or incorrect. So it requires management to make sure connections that are not formed on beam centerlines are joined in the correct way.

[0132] When the beam 10b is cut to length the beam is complete except for painting if required. The connection is completed by drilling four corresponding holes in the mating beam, thus voiding a welding process during manufacturing. If the beam 10b is not connected to another beam at the other end, than the connection plate 30 is simply cut from the end of the beam 10b.

[0133] The embodiment thus supplies pre-primed standard length beams to a fabricator with prefixed connection plates fixed to each end. The pre-fixed cleats 30 to each end, in its preferred form centrally located on the beam axis, makes the fabricators manufacturing material efficient and speeds up production by reducing the need for welding cleats for connections in the production line.

[0134] The preferred embodiment provides an improved design for a range of structural steel beams, that will have a number of beams, whereby each beam depth matches the corresponding depth of each timber floor joist.

[0135] The preferred embodiment provides having a flange thickness common to all beam sizes and less than or equal to the maximum allowable notch depth in the timber joists.

[0136] The preferred embodiment provides having beam capacity within a beam nominal depth is increased or decreased by varying the width of the top and bottom flange together.

[0137] The preferred embodiment provides standardisation of the notching requirement of the range of timber joists so that it will remain the same for all beams.

[0138] The preferred embodiment provides a beam which uses beam flange thickness less than the allowable notch depth in the timber I joists

[0139] The preferred embodiment provides the standardisation of the beam depths and standardising joists notching sizing.

[0140] The preferred embodiment provides common thickness flanged beams enabling standard notching and cut to length joist supply to site by a manufacturer, or as a minimum supplying the standard packs to site with one or both ends of each timber joist notched top and bottom during manufacture so that at least one end is available to fit a standard beam, reducing labour costs on site.

[0141] The framing companies cannot at this time supply joists cut to length and pre notched to site mainly due to the complications caused by the beam differences. The above embodiment will make a real difference in the site labour costs reductions if they were cut to length and pre-notched. The invention allows this to be done now because of the standardised flange widths and the flange thickness.

[0142] The beams are manufactured off site and provided in predetermined depths and lengths, they are pre-notched in the top and bottom flanges at each end or on one end only of the timber I joists, transported to the site in cut to length and ready to use to construct the floor structure.

[0143] Conventional floors squeak if the ends of the joist are in contact with the web of the steel beam, which is a common problem in the industry. The standard length notching of the above embodiment will overcome that problem as well.

[0144] The preferred embodiment allows to manufacture beams to standard lengths that suit their application maximising efficiency of manufacturing and minimising offcut wastage within the domestic building industry.

[0145] The preferred embodiment provides a range of simple and optimised structural beam cross sectional shapes that will standardise and significantly reduce the installation costs of labour and material in floor structures built on site.

[0146] Although a preferred embodiment of the present invention has been described, it will be apparent to skilled persons that modifications can be made to the embodiment shown.

[0147] The beam flange thickness is an avenue for optimization of the process, whereby the joists allowable maximum notch depth is not exceeded by the flange thickness. The optimal flange thickness suits the beam capacity and material efficiency to suit the span range of a depth of beam in the most efficient way.

[0148] The flange thickness may not be the same in each depth grouping of the beams, however it is preferred that they are the same for all the different beam depths. In the preferred embodiment, the flange thickness is 10 mm which works for both the 240 mm and 300 mm deep beams.

[0149] The reason why the larger flange beam of nominal 200 mm depth is that in many cases, the beams are used to support the external brick wall as well as the timber floor joists and timber wall. The wider flange allows the brick wall to be supported on one side of the beam flange, and the joists and timber walls on the other side of the top flange.

[0150] The brickwork can overhang the beam flange max 25 mm, the timber wall frame cannot overhang more than 10 mm. However, when the flooring is sandwiched between it obviously can be more, hence 250 mm overall wall thickness including 90 mm timber wall, 50 mm cavity and 110 brickwork with 25 mm overhang, has the 90 mm wall frame hang over the internal half of the top flange by 25 mm,

[0151] In another embodiment of the beam, it now can be made to a 240 mm or 300, deep, whereas they are currently 250 mm (pfcparallel flange channel) plus a 10 mm plate or 260 mm, or 230 mm pfc with 10 mm plate making it 240 mm with a very thick bottom flange, or a 300 pfc with a 10 mm plate or 310 mm overall and not useful.

[0152] The invention in one embodiment provides having the beam overall depth being equal to the timber joist depth.

[0153] The connection end plate is centrally located at mid height of the beam and is symmetrical about the web, so the vertical centre line of the connection plate is to the centre of the beam web.

[0154] The joist in the example is a timber I-beam but can alternatively be solid timber, steel I beam, steel trussed joist, timber trussed joist, or purlin joists.

[0155] The maximum flange thickness can be up to 16 mm rather than the example 12 mm described. This allows an opportunity to optimise to suit any joist system and any future joist system allowing a deeper notch depth, since the beams flanges in this depth range are around 16 mm maximum.

[0156] The optimal (preferred) form of the beam connection to suit the current timber I joists is 12 mm flange thickness, a smaller beam flange width of 125 mm and larger beam flange width of 200 mm.

[0157] FIG. 7 shows a beam 10c according to another embodiment. In this example, the top flange 11 extends further to a first side of the beam web 12 (right side in the drawing) and extends only a short distance from a second opposite side of the beam web 12 (left side in the drawing). The bottom flange 13 extends further to the second side of the beam web 12. The extended bottom flange 12 is useful laying a course of bricks thereon at the space 19b, while the joist 10/10b extends from the opposite (first) side at the space 19a.

[0158] The present invention provides a beam and joist set comprising an I cross-section steel beam and a timber joist, wherein the beam depth and the joist height are the same. A notch is pre-formed/pre-cut to the top and bottom surfaces in a first end of the joist, and preferably in both ends of the joist. The notches have a depth substantially equal to a thickness of the top and bottom flanges or just slightly deeper.

[0159] In use, the first end of the joist is disposed between the top and bottom flanges of the beam such that the top surfaces of the beam and the joist are level, and the lower surfaces of the beam and the joist bottom flanges are also level.

[0160] If the second end of the joist is pre-notched, the second end can also be inserted into a second steel beam.

[0161] The joist is preferably cut to length prior to delivery to site.

[0162] The timber joist is preferably an I cross-section joist having a top flange and a bottom flange with a web extending therebetween, wherein the notches are formed in the top and bottom flanges.

[0163] The present invention also provides a method of construction using the beam and joist set of the above including supplying the timber joist to site with the notches at the first end pre-cut prior to delivery to site; and disposing the first end of the joist between the top and bottom flanges of the beam.

[0164] The present invention also provides a method of construction using the beam and joist set of the above including supplying the timber joist to site with the notches at the first and second ends pre-cut prior to delivery to site, disposing the first end of the joist between the top and bottom flanges of a first beam, and disposing the second end of the joist between the top and bottom flanges of a second beam.