Classifications

• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
  • E04C2/00—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels
  • E04C2/02—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by specified materials
  • E04C2/08—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by specified materials of metal, e.g. sheet metal
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
  • E04D3/00—Roof covering by making use of flat or curved slabs or stiff sheets
  • E04D3/24—Roof covering by making use of flat or curved slabs or stiff sheets with special cross-section, e.g. with corrugations on both sides, with ribs, flanges, or the like
  • E04D3/30—Roof covering by making use of flat or curved slabs or stiff sheets with special cross-section, e.g. with corrugations on both sides, with ribs, flanges, or the like of metal

Definitions

• the present invention relates to a sheet metal section, especially for roof, wall or floor struc ⁇ tures, comprising an upper flange which at its edges passes into two sloping webs, each formed with a stif- fening and passing, at its lower edge, into an out ⁇ wardly bent lower flange, the upper flange being sub ⁇ stantially wider than the lower flanges and having, at its junction with each web, a longitudinal, stiffening fold.
• a technique frequently used for erecting roofs is to arrange transverse ridges at a suitable centre distance on the so-called main beams. Subsequently, metal sheeting, insulation and the roof covering pro ⁇ per are mounted in this order on the said ridges.
• transverse and longitudinal stiffening beads or folds in a sheet metal section of this type is, of course, more complicated and consequently more expensive than if the section is provided with longitudinal stiffen ⁇ ings only.
• transverse embossments of the type as shown in the above patent specification are made in the sheet, there is also a risk that cracks or em- brittlements are formed in the upper flange.
• One object of the present invention is therefore to provide a sheet metal section which can be manufac- tured more easily and thus at lower cost as compared with previously known sheet metal sections of similar type.
• Another object is to provide a stiffened sheet metal section having higher strength and a lower ten- dency to buckling, particularly when subjected to load from above, such as snow loads.
• One more object is to provide a sheet metal sec ⁇ tion which may serve as a walking surface during erec ⁇ tion of the roof covering.
• a still further object of the invention is to pro ⁇ vide a sheet metal section whose design makes for a lower tendency to cracks or embrittlements during the process of manufacture.
• the inventive sheet metal section mentioned by way of intro ⁇ duction is characterised in that the centre portion of the upper flange is of arched cross-section throughout its entire length, the arch bulging upwards in relation to the webs.
• the cross-section of this arch may have the form of an arc of a circle, parabola or ellipse, or a series of straight portions which together form the arc of a circle, parabola or ellipse.
• Fig. 1 is a per ⁇ spective view of a sheet metal section according to the invention
• Fig. 2 is a cross-sectional view of the sheet metal section in Fig. 1
• Figs. 3 and 4 show alternative embodiments of the sheet metal section.
• Fig. 1 shows an embodiment of a sheet metal beam or a sheet metal section 1 according to the invention.
• the section 1 which has a thickness of for example 0.7-1.5 mm, comprises an arched upper flange 2 and two sloping webs 3. Each web 3 has at its lower end an outwardly bent flange 4 with a bead 5.
• each flange 4 When neces ⁇ sary, more than one such bead can be formed in each flange 4.
• the outer edge of at least one flange 4 is upwardly bent to form an edge stiffening 6.
• a plurality of sections 1 When erecting a roof structure, a plurality of sections 1 are arranged on the main beams (not shown), the flanges 4 of each section 1 being engaged with each other in prior art manner. It will be appreciated that safe engagement is promoted by means of the beads 5 and the edge stiffenings 6.
• each web 3 is, in the embodiment shown, provided with two stiffenings in the form of longitu ⁇ dinal folds 7.
• the number of folds 7 is, however, of no import to the invention.
• the transition between the arched portion 2 of the upper flange and each web 3 comprises on the one hand a stiffening ridge 8 which imparts to the section 1 sufficient ridgidity and strength, in particular when the flange 2 is sub- jected to load from above, and, on the other hand, a longitudinal fold 9 which also stiffens the section 1.
• the highest point of the arched portion is on a level with or higher than the highest points of the stiffening ridges.
• the section is formed of the lower flanges 4, the webs 3 connected therewith and an upper flange extending between the upper ends of the webs 3 and comprising ridge-forming flange portions 11, downwardly bent flange portions 12 and an arched flange member 2, such that the valleys be- tween the flange portions 12 and the arched flange mem ⁇ ber 2 form longitudinal stiffening folds 9.
• the invention is not limited to the arched shape of the upper flange 2 as shown in the drawings, and in actual practice the arch may be formed of an outwardly bulging arc of a circle, ellipse or parabola, or a series of straight portions which together form an arch.
• the stiffen- ings of the webs 3 are formed of folds 7 extending in the longitudinal direction of the section 1, but these stiffenings can of course also be formed of stiffening folds or beads (not shown) which are transverse to the longitudinal direction of the section 1.
• the stiffenings may also comprise other types of indentations, emboss ⁇ ments or the like.
• the width of the upper flange 2 is substantially larger than the width of each lower flange 4, the width ratio accord- ing to the embodiment shown being about 7.5 to 1.
• the invention is, of course, not limited to this very ratio, but the widths mentioned may be changed as re ⁇ quired, without departing from the inventive idea for that reason.
• the sheet metal section can be modified such that it comprises two or more interconnected sheet metal sections of the type described above.
• Figs. 3 and 4 show modifications with two and three interconnected sheet metal sections, la and lb, respectively.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Roof Covering Using Slabs Or Stiff Sheets (AREA)
• Bending Of Plates, Rods, And Pipes (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20363277

Family Applications (1)

Country Status (3)

Cited By (1)

Citations (7)

• 1986
  • 1986-01-29 SE SE8600401A patent/SE461286B/sv not_active Application Discontinuation
• 1987
  • 1987-01-29 WO PCT/SE1987/000041 patent/WO1987004747A1/en unknown
  • 1987-09-25 DK DK507387A patent/DK159563C/da not_active IP Right Cessation

Patent Citations (7)

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