FR2840001A1 - Girder, as part of a concrete mold structure, is of reinforced plastics with a structured longitudinal groove to take a wood stake and a base plate with openings to take anchors for fastening at a support - Google Patents

Abstract

The girder (1), especially for a concrete mold, has a framework or profiles of glass fiber reinforced plastics to define a longitudinal groove (41) and a base plate (26,27). A wood stake (6) is held within the groove. The base plate has openings (30) to take anchors (34) through them, to fasten the girder to a support.

Description

1 2840001

  The present invention relates to a beam operable to support

  shuttering panels, and has a method of manufacturing this beam.

  The technical field of the invention is that of the manufacture of beams of

  support of temporary structures for formwork of concrete structures.

  Such beams are traditionally made of wood or metal.

  In patent FR 2,715,959, there is described a support beam formwork panels formed by a metal profile and a wooden insert housed in a U-shaped groove of the metal profile; the profile has an H-shaped section closed at its base by a wall forming a bearing surface of the profile; The wooden insert is forced back into the groove in which it is held in place and clamped by two clamped and striated wings; the bearing face of the profile is extended by two pierced side wings; the perks provided in these wings allow the fixing of the

  Beam has its support by nails engages in these cages.

  It has furthermore been proposed to manufacture formwork support structures made of plastic material reinforced by glass fibers, in particular profiles obtained by pultrusion; nevertheless, these structures have not, to the knowledge of

the inventor, of success.

  An object of the invention is to propose a new beam capable of supporting

  formwork, and method of manufacturing the same.

  An object of the invention is to provide a formwork beam and its

  manufacturing process, which are improved.

  An object of the invention is to provide a nonmetallic formwork beam

  presenting performances similar to those described in patent FR 2 715 959.

  According to a first aspect, the invention proposes a beam, in particular a formwork beam, characterized in that it comprises a frame or profile of reinforced plastic, the structure or profile delimiting a longitudinal groove and having a sole, the beam with a wooden batten engages in the

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  groove, the sole having one or more cavite (s) apse (s) to cooperate with

  fixing members for fixing the beam to a support.

  The invention particularly provides a formwork beam which is essentially constituted of a hollow frame of plastic material reinforced by longitudinal fibers, the structure delimiting a longitudinal groove, and a wooden batten inserted into the longitudinal groove; The frame comprises at least one support plate (generally two support pads) which is (are) pierced (s) with a plurality of orifices allowing the passage of a fastener - such as a nail

  - The beam has a structure (beam or panel in particular) supporting the beam.

  It has indeed been found that, surprisingly, it is possible to pierce the sole (s) of such a beam without appreciably reducing the performance of the beam, even though these perceptions cause an interruption of part of the longitudinal fibers used to reinforce the framework of the beam, moreover in a part (sole) thereof, whose contribution to the resistance to the loads of the

beam is preponderant.

  It has also been found that it is possible to keep the wooden battens in the groove by pinching walls of the framework, while the modulus of elasticity of the reinforced plastics material is considerably less than that of the metals: is usually about twice as low as that of aluminum; it was further noted that this maintenance could generally be achieved without

on the inner side of these walls.

  It has furthermore been found that it is possible to make such a beam whose linear mass is comparable in performance - inferior, equal or hardly

  greater than a similar beam with an aluminum frame.

  Preferably, for this purpose, and according to another aspect of the invention, there is provided a beam comprising a fiber reinforced plastic profile (of mineral origin) - in particular glass fibers - and a wooden battens lodged and maintained in a longitudinal groove of the profile, the profile comprising two upper lateral wings - at the head - which border the opening of said longitudinal groove, as well as two lower lateral wings - in the foot forming said flanges, the thickness of said lateral flanges upper and lower - being greater than the thickness

  walls forming the central part of the profile.

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  Preferably, the ratio of the thickness of the lateral wings to those of the central walls of the profile is in a range from 1.2 to 2, in particular from 1.4 to 1.8; preferably also, the thickness of the walls of the central portion is between 3 and 5 mm for a beam of 160 mm, while the thickness of the lateral wings is between 5 and 10 mm, in particular between 6 and 9 mm ; preferably, the line mass (including the wood insert) of such a beam is less than or equal to kg / m. Preferably, these lateral wings project protruding at the ends (upper and lower) of the main longitudinal walls of the profile in the form of H. the width at the head of the profile being substantially equal to the width at the foot of the profile; this allows that when two wind beams placed side by side (parallel) in overlapping, they rely on one another by their respective lateral wings, in foot and in party, when they are subjected to a lateral load ; as a result, the transmission of lateral forces between the beams is improved; this is particularly the case of two beams placed on a common forest fork; preferably furthermore, the width of the

beam is less than 80 mm.

  In order to facilitate the cleaning of the beams, the outer face of the main longitudinal walls of the profile is preferably smooth and devoid of grooves and / or ribs. According to another aspect, the invention proposes a beam comprising a nonmetallic frame having a longitudinal groove, and a wood insert - or a similar material - housed in the groove, the structure preferably comprising proeminent lateral soles in the foot. and in fete, as well as a second longitudinal groove, opposed to the first, which opens (in foot) by an opening of width less than the width of this second groove, which is planned and adapted to receive organ holidays ( such as screws) for fixing the beam on a support such as a support plate; these organs can slide in this

  groove, which facilitates the construction of lightweight and resistant formwork structures.

  Preferably, the second groove is specially adapted to receive at least two types of linker parties having two distinct geometries; preferably, for this purpose, the profile in a cross section of this second groove comprises series of segments forming a stairway trace; to these

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  segments correspond to support faces for said holiday of connecting members,

  different widths adapted to said distinct geometries.

  According to another aspect, the invention proposes a method for manufacturing formwork beams comprising the following operations: At continuous impregnation of fibers with a thermosetting resin,

  The impregnated fibers of resin are passed through a mold -

  or die - so as to form at the output of the mold a profile of the desired shape of the beam, which comprises a longitudinal cavity in the central part, two foot insoles and a groove in the party, A is caused the polymerization of the resin of the profile by heating, in particular by passing through an oven, to cut the profile in tron, cons of desired length for the beam, is pierced each sole of each beam of a plurality of orifices, which wind preferably regularly distributed along the same footing, A is inserted in the groove of the beam a wooden batten having a length substantially identical to that of the beam, and A is fixed at each end of each beam a piece of

  protection of this end against shocks.

  Preferably, a polyester resin and glass fibers are used.

  Pond content in the framework generally varies between 40% and 80%.

  Preferably, when the frame (the profile) of the beam delimits a longitudinal cavity (tubular), said end piece closes the cavity so as to avoid

  accumulation of debris in this cavity.

  The invention makes it possible to produce formwork supporting beams resistant to loads and shocks, which are not very sensitive to variations in temperature and hygrometry,

  easy to clean, with a high life expectancy and at a reasonable cost.

  s 2840001 Other advantages and features of the invention will be understood through

  of the following description which refers to the accompanying drawings, which illustrate without any

  limiting character of the preferred embodiments of the invention.

  FIG. 1 illustrates in cross-sectional view a first embodiment of a beam according to the invention, incorporating a wooden spar and equipped with a fixing screw, which is slidable in a longitudinal groove provided in FIG.

sole of the beam.

  FIG. 2 illustrates, in partial sectional view, a first formwork structure including a primary beam according to the invention, which extends parallel to the plane of FIG. 2 and which supports a secondary beam according to the invention, which extends perpendicularly on the plane of FIG. 2, this rear beam supporting a

formwork panel.

  FIG. 3 is a partial sectional view of a second formwork structure comprising a beam according to the invention, which is resting and bolted on a

  platinum of a forest, and which supports a formwork panel.

  FIG. 4 is a schematic partial perspective view of a formwork support structure comprising two identical beams according to the invention which lie side by side by one of their respective ends on a platen.

fork - equipping a forest

  FIG. 5 is a fragmentary diagrammatic fragmentary perspective view of an end portion of a beam structure according to a second embodiment.

  of the invention, as well as a protective piece of the end of the beam.

  As shown in FIGS. 1 to 3 in particular, the beam 1, 2 is constituted by a truncated con section 3, 4, 5 hollow in a longitudinal groove above which is inserted a cleat 6, 7 of wood; the beam 1 (respectively 2) has an axis

  longitudinal 8 (respectively 9), along which extend the profile and the cleat.

  The profile (such as 3 figure 1) incorporates a plurality of glass fibers 100 extending parallel to the axis 8, throughout the section of the profile (only a few wind fibers illustrated in Figure 1 to not impair its clarity) , and that wind continuous and

  embedded in a polyester matrix that they reinforce.

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  The profile comprises two main longitudinal walls 10, 11 which extend substantially along two parallel longitudinal planes 12, 13 (FIG.

  respective traces in the plane of Figure 1 wind marked 14,15.

  Each of these walls has in its central part a thickness 16, 17 S which is smaller than its thickness 18, 19 in the head on the one hand, and its thickness

, 21 feet on the other hand.

  Each of these walls has - at the head - an upper end curved forming an upper lateral wing 22, 23 protruding with respect to the outer face

24.25 from the wall.

  The lower end of the walls 10, 11 is extended - at the foot - by a thick lower wing 26, 27 forming a support plate of the profile on a support; each wing 26, 27 forms a kind of "T" with the wall 10, 11 which it extends respectively (in cross-sectional view as illustrated in Figures 1 and 3); The thickness 28, 29 of these wings 26, 27 is greater than the thickness 16, 17 of the central part of the walls 10, 11 and is close to that 20, 21 of the lower ends of

these walls.

  Each sole 26, 27 has an outer "outer" portion 26a, 27a protruding from the outer face 24, 25 of the walls 10, 11, and comprises a portion 26b, 27b "internal" laterally extending in the extension of the portion

"external".

  Each outer portion 26a, 27a of the flanges 26, 27 is pierced with orifices 30 passing through the soleplate, extending along axes 31 which form an angle 32 with the planes 12, 13 (trace 14, 15) whose value is close to 30 degree; preferably, these orifices are regularly spaced along the soles of a pitch 33 (FIG. 5), the orifices situated at a first side of the profile (for example on the portion 26a) being located at measured positions along the the longitudinal axis 8, 9 - which are offset with respect to the position of the orifices located at a second side of the profile (for example on the portion 27a); this makes it possible to prevent two nails 34, 35 (FIG. 2) extending through orifices substantially facing each other, from interfering with or deteriorating the wooden insert (reference 7 FIG. ) in which they wind plants; in the case where the value of the offset between these positions of the opposing holes is equal to half of their common pitch, the orifices are then arranged in staggered rows along the

  else - of a median longitudinal plane and symmetry - of the profile and the beam.

  The main lateral walls 10, 11 wind connected together by two longitudinal connecting walls 36 and 37, which wind parallel to each other and orthogonal to the walls 10, 11 (Figures 1 to 4); in the variant embodiment illustrated in FIG. 5, the lower linkage wall 37a is bent and connects the lateral walls 10, 11 with

  the first edition of the 26th and 27th.

  The walls 10, 11, 36, 37, the flanges 26, 27 and the upper wings 22, 23 constitute a profile obtained by molding polyester and reinforced by the longitudinal fibers 100; this frame of constant section is hollow, the walls 10, 11, 36, 37 delimiting a longitudinal central cavity 40 of substantially rectangular section; the upper portions of the walls 10 and 11 and the wall 36 also delimit an upper longitudinal groove 41 receiving the cleat 6, while the connecting wall 37, 37a, the flanges 26, 27 (and the lower portions of the walls 10, 11 FIGS. 1 to 4) delimit a lower longitudinal groove 42 in which

  can slide holidays 43 (rectangular or square) screw 44.

  Such a screw (FIGS. 1 and 3) makes it possible to fix the beam 1, by its base 26, 27, on a plate 45 provided at the upper end of a stud 46 of vertical axis 47, a

  using a nut 48 complementary to the screw 44.

  In the case of the structure shown in Figure 4, the plate 45 supported by the stay 46 is rectangular and equipped at each of its four corners a baluster 49 serving as a side stop for the respective ends of the two beams 1 resting side by side on the stage without being fixed; in the case where a lateral thrust is applied to a first of the two beams, they are supported one on the other by both their upper wings proeminentes (22, 23 Figure 1) and their outer portions of soles (26a, 27a Figure 1), when the width 39 at the foot of these beams

  is equal to their width 38 in party.

  The inner faces 50, 51 (Figure 5) of the upper portions of the walls 10, 11, which grip the cleat housed in the groove 41, wind smooth and substantially parallel; the cleat is inserted without play in this groove, its upper face 52 being substantially flush or slightly recessed (hollow) - a few tenths of millimeters - with respect to the upper bearing face 53, 54 of the wings 22, 23 ( figure 1);

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  the holding in position of the batten in the groove can be further supplemented by self-tapping screws extending through the walls 10 and 11 of the profile and penetrant

in the cleat.

  The lower groove 42 illustrated in FIGS. 1 to 3 has, in the upper part, a first width 55 (FIG. 2) adapted to the dimensions of a first type of screw head; it has in part median a second width 56 less than the

  first width 55 and adapted to the dimensions of a second type of screw head -

  or other liaison body - distinct from the first type; the groove 42 has, at the bottom part, a mouth delimited by the flanges, whose width 57 is smaller than the second width 56 and adapted to the threaded part - or equivalent means - of the screws

said first and second types.

  As illustrated in Figure 2, the batten 6 of the beam 1 allows the nailing of a formwork panel 58 supported by the beam 1, while the batten 7 of the beam

  2 allows the nailing of the flanges 26 and 27 of the beam 1 supported by the beam 2.

  With reference to FIG. 5, a metal piece 59 is provided to be secured to each end of the beam, to protect it against shocks; this piece, which can be obtained by cutting and bending sheet metal, comprises a flat rectangular central part 60 able to seal a substantial part of the mouth of the cavity 40, two first planar wings 61 to be inserted in the cavity 40 and extending along the inner face of the walls 10, 11 of the beam, and two second planar wings 62 extending in the extension of the wings 61, apses to be inserted into the groove 41 and to extend along wall faces 50 and 51

delimiting this groove.

  Each end piece 59 is preferably secured to the walls 10, 11 of the beam by self-drilling screws extending through these walls and wings

61 and 62 of the piece.

  The beams according to the invention can be obtained by the pultrusion technique making it possible to obtain sections of reinforced fiber profiles; these

  tron, then cons drows and equipped with a cleat and two pieces of extremite.

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Claims (12)

  1. Beam (1, 2) characterized in that it comprises a frame or profile reinforced plastic, the structure or profile delimiting a groove (41) longitudinal and having a sole (26, 27), the beam having a cleat (6, 7) engaged in the groove, the sole having one or more cavities   (30, 42) adapted to cooperate with fastening members (34, 35, 43, 44).   Beam according to claim 1, wherein the sole comprises a plurality   orifices (30) designed to receive nails (34, 35).   Beam according to claim 1 or 2, wherein the sole comprises - and / or   delimit - a groove (42) designed to receive a head (43) of screws (44).   4. Formwork beam according to any one of claims 1 to 3, in   which frame or profile comprises longitudinal fibers (100) embedded in a thermosetting matrix.   5. Pout're according to any one of claims 1 to 4, wherein   The groove or profile comprises two main walls (10, 11), two upper wings (22, 23) extending the main walls (10, 11) and bordering the opening of the groove (41) receiving the cleat, and two wings (26, 27) extending the main walls (10, 11) and forming the sole, the thickness of the wings (22, 23, 26, 27) being   greater than the thickness (16, 17) of the central part of the main walls (10, 11).   6 "Beam according to iune quelconcZue of claims 1 to 5 'whose arg er was   (38) is equal to its foot width (393.   7. Beam according to any one of claims 3 to 6 wherein the groove   (42) extends longitudinally and is adapted to receive at least two types of connecting body heads having at least two distinct geometries, which can slide in this groove.   8. Beam according to any one of claims 1 to 7, wherein   the frame or profile delimits a longitudinal cavity (40), and which comprises two parts   (59) Apses to seal the cavity and protect the ends of the beam against shocks. l 2840001   9. Beam according to any one of claims 1 to 8, wherein the faces   internals (50, 51) of the pine walls, cant the cleat, and / or the outer faces (24, 25) of   main walls (1 O. 11) wind lacking ribs and / or grooves.   The blur as claimed in any one of claims 1 to 9, which has a   Its height is 160 mm and a linear mass less than or equal to 5 kg / meter.   11. A method of manufacturing formwork beams (1, 2) comprising the following operations: I A Continuously impregnated fibers (100) with a resin | The resin impregnated fibers are passed through a mold or die to form a profile of the desired shape of the beam, which has a longitudinal cavity (40) in the form of a mold. | central portion, two flanges (26, 27) in the foot and a groove (41) in I fete,! The polymerization of the profile resin is caused by heating, in particular by passing through a furnace, 1., A. The profile is cut into lengths of desired length for the beam. Each bead beam flange is pierced with a plurality of orifices (30), which wind is preferably distributed regularly along each flange, to which a cleat (6, 7) is inserted into the groove of the beam. wood having a length substantially identical to that of the beam, and lt A is fixed at each of the two ends of each beam one piece (59)   I protect this end against shocks.   The method according to claim 11, wherein a polyester resin and glass fibrel are used, the weight content of which in the framework is within a range. ranging from 40% to 80%.