Classifications

• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
  • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
  • E04C5/01—Reinforcing elements of metal, e.g. with non-structural coatings
  • E04C5/02—Reinforcing elements of metal, e.g. with non-structural coatings of low bending resistance
  • E04C5/03—Reinforcing elements of metal, e.g. with non-structural coatings of low bending resistance with indentations, projections, ribs, or the like, for augmenting the adherence to the concrete
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
  • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
  • B21J5/06—Methods for forging, hammering, or pressing; Special equipment or accessories therefor for performing particular operations
  • B21J5/08—Upsetting
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
  • B21K1/00—Making machine elements
  • B21K1/56—Making machine elements screw-threaded elements
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
  • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
  • E04C5/16—Auxiliary parts for reinforcements, e.g. connectors, spacers, stirrups
  • E04C5/162—Connectors or means for connecting parts for reinforcements
  • E04C5/163—Connectors or means for connecting parts for reinforcements the reinforcements running in one single direction
  • E04C5/165—Coaxial connection by means of sleeves

Definitions

• the present invention relates to a high-strength reinforcing bar for reinforced concrete, an assembly comprising such a reinforcing bar, a method of assembling a reinforcement for reinforced concrete and a method of manufacturing a reinforcement for reinforced concrete. .
• the document FR 2,639,054 discloses a reinforcement for reinforced concrete comprising:
• a first and a second reinforcing bar each comprising an extension portion provided with attachment asperities, and a pushed end portion extending the extension portion and on which a thread or helical thread is formed, and
• a threaded connection sleeve arranged to cooperate with the threads formed on the end-end portions of the first and second reinforcing bars.
• the assembly of the first and second reinforcing bars can then be easily achieved by performing the following steps:
• the cold discharge of a large portion of the reinforcing bar causes, on the one hand, a modification of the crystalline structure of said portion, which may cause embrittlement of the reinforcing bar at the level of the portion of the reinforcing bar. end repressed, and therefore a risk of rupture of the rebar at this location, and secondly a remanent deformation of the rebar when it is put in tension.
• the present invention aims to remedy these disadvantages.
• the technical problem underlying the invention therefore consists in providing a high-strength reinforcing bar for reinforced concrete which is of simple and economical structure, while ensuring a reliable and easy assembly of a reinforcement for reinforced concrete.
• the present invention relates to a high-strength reinforcement bar for reinforced concrete, comprising:
• an extension portion comprising, on its outer surface, attachment asperities designed to promote adhesion between the reinforcing bar and the concrete, and
• a discharged end portion provided with a thread intended to cooperate with a tapping formed in a connecting sleeve, the threaded diameter of the thread being greater than or equal to the nominal diameter of the reinforcing bar
• the discharged end portion comprises a first substantially cylindrical portion, and at least a second portion disposed between the first portion and the extension portion, the second portion being of decreasing general section towards the portion of extension, the second part having a length greater than or equal to the length of the first part.
• Such a configuration of the upset end portion makes it possible to limit the degradations of the crystalline structure of said end portion during the discharge step of the reinforcing bar, and thus to greatly limit the risks of rupture and remanent deformation of the rebar at this location, without requiring an over-size of said rebar.
• the reinforcing bar according to the invention thus ensures a reliable assembly of a reinforcement for reinforced concrete.
• the thread extends at least in part over the first and second portions of the end portion.
• the second part comprises a longitudinal core and attachment asperities formed on the outer surface of said longitudinal core.
• the longitudinal core of the second portion is of decreasing general section in the direction of the extension portion.
• the second part extends in the extension of the first part.
• the second portion extends to the extension portion.
• the first part extends from the corresponding free end of the reinforcing bar.
• the second part has a length greater than twice the length of the first part.
• the second portion of the end-discharge portion has a length greater than or equal to the nominal diameter of the reinforcing bar.
• the second portion of the end-discharge portion comprises at least a first substantially frustoconical portion having its largest base facing the first portion of the end-end portion, and a second portion substantially frustoconical disposed between the first substantially frustoconical portion and the extension portion, the second substantially frustoconical portion having its largest base facing the first substantially frustoconical portion.
• the first substantially frustoconical portion has a slope of between 6 and 18%, and preferably between 8 and 16%.
• the second substantially frustoconical portion has a slope of between 2 and 5%, and preferably between 2.2 and 4.5%.
• the second substantially frustoconical portion has a length greater than or equal to the length of the first substantially frustoconical portion.
• the second substantially frustoconical portion extends in the extension of the first substantially frustoconical portion.
• the second substantially frustoconical portion has a length greater than or equal to the length of the first portion.
• the longitudinal core of the second portion comprises at least a first substantially frustoconical core portion having its largest base facing the first portion, and a second substantially frustoconical core portion disposed between the first core portion and the extension portion, the second core portion having its largest base facing the first core portion.
• the second core portion has a length greater than or equal to the length of the first portion.
• the second core portion has a length greater than or equal to the length of the first core portion.
• the thread extends at least in part over the first and second core portions.
• the diameter of the second core portion at its largest base is greater than the nominal diameter of the reinforcing bar.
• the cross section of the end portion discharged at the thread bottom of the thread is greater than a cross section of the extension portion.
• the cylinder circumscribing the extension portion and having an axis parallel to the longitudinal axis of the extension portion has a smaller diameter than the bottom thread diameter of the thread.
• circumscribed cylinder is meant the smaller diameter cylinder including all the points of the extension portion.
• the projection of the extension portion on a plane orthogonal to the longitudinal axis of the rebar defines a first surface and the projection of the cross section of the end portion discharged at the Thread bottom thread on said plane defines a second surface, the first surface being inscribed in the second surface.
• the thread extends over a longitudinal length that is less than or equal to the length of the end-pushed portion.
• the cross section of the end portion discharged at the thread bottom of the thread is greater than each cross section of the extension portion.
• the threading provided on the upset end portion is cylindrical.
• the discharged end portion extends in the extension of the extension portion.
• the discharged end portion has a length of between 0.5 and 1, 4 times the nominal diameter of the reinforcing bar.
• the end portion has a length corresponding to about 0.6 times the nominal diameter of the reinforcing bar (for example when the reinforcing bar is intended for a standard assembly, also called LS bond, that is to say that is, allowing a rotation drive of said reinforcing bar when it is assembled to another connecting bar by means of a connecting sleeve
• the end-end portion has a length corresponding to approximately 1, 2 times the nominal diameter of the reinforcing bar (for example when said reinforcing bar can not be rotated when assembled to another connecting bar by means of a connecting sleeve, that is to say for example during an LSR link or an LCE link).
• the attachment asperities comprise at least one longitudinal rib, and preferably two longitudinal ribs substantially diametrically opposed.
• the attachment asperities comprise a plurality of oblique ribs, also called locks, the oblique ribs having for example a general crescent shape.
• the extension portion comprises a longitudinal core on the outer surface of which are formed the attachment asperities.
• the extension portion and the repressed end portion extend substantially coaxially.
• the present invention further relates to a reinforcement assembly for reinforced concrete, comprising a reinforcing bar according to the invention, and a connecting sleeve comprising a thread arranged to cooperate with the threading provided on the end portion repressed.
• the discharged end portion has a length greater than or substantially equal to the longitudinal length of the tapping provided on the connecting sleeve.
• the assembly further comprises a stop nut intended to cooperate with the thread on the one hand provided on the end end portion and on the other hand the connecting sleeve.
• the stop nut is intended to cooperate with one end of the connecting sleeve.
• the discharged end portion has a length greater than or substantially equal to the sum of the longitudinal length of the tapping provided on the connecting sleeve and the height of the stop nut.
• the present invention also relates to a method of assembling a reinforcement for reinforced concrete, comprising the following steps:
• first and second reinforcing bars each comprising a pushed end portion and an opposite end portion situated opposite the end portion; pushed back and provided with a thread
• the method further comprises: a step performed prior to screwing the connection sleeve onto the end-end portion of the second reinforcing bar and screwing a stop nut onto the portion; end-end of the second reinforcing bar, and
• the present invention further relates to a method of manufacturing a high-strength reinforcement bar for reinforced concrete, comprising the following steps:
• a reinforcing element comprising an extension portion provided on its outer surface with snap beadings, and an end portion
• the threading is defined by a diameter / pitch pair that does not comply with the international threading standards, and this in such a way as to define a specific torque as a function of the armature diameters and the diameter. link to achieve.
• the discharge step is performed cold.
• the discharge step is performed at variable speed, for example continuously or in stages.
• the discharge step is successively carried out according to a first delivery mode defining a first speed range and according to a second delivery mode defining a second speed range, the speeds belonging to the second speed range being less than the second speed range. smaller speeds belonging to the first speed range.
• the discharge speed is degressive during the first delivery mode.
• Figure 1 is a partial side view of a reinforcing bar according to a first embodiment of the invention.
• Figure 2 is a schematic partial view of the reinforcing bar of Figure 1.
• Figures 3 and 4 are side views of two reinforcing bars according to the invention being assembled according to a first assembly method.
• Figures 5 and 6 are side views of two reinforcing bars according to the invention being assembled according to a second method of assembly.
• Figure 7 is a schematic partial view of the reinforcing bar of Figure 1 during manufacture.
• FIG. 8 is a view of an extension portion and a pushed end portion belonging to a reinforcing bar according to a second embodiment of the invention, projected on a plane orthogonal to the longitudinal axis of the rebar.
• Figure 1 shows a reinforcing bar 2 high adhesion for reinforced concrete.
• the reinforcing bar 2 is preferably made of steel.
• the reinforcing bar 2 comprises an extension portion 3 and a raised end portion 4 extending in the extension of the extension portion 3.
• the extension portion 3 and the end portion 4 s pushed back extend substantially coaxially.
• the extension portion 3 comprises a substantially cylindrical longitudinal core 5 and attachment asperities provided on the outer surface of the longitudinal core 5.
• the attachment asperities have two diametrically opposite longitudinal ribs 6, and a plurality of oblique ribs 7, also called locks, arranged between the longitudinal ribs 6.
• the oblique ribs 7 may for example have a general crescent shape.
• the upset end portion 4 comprises a first substantially cylindrical portion 41 extending from the corresponding free end of the reinforcing bar 2, and a second portion 42 extending the first part 41.
• the second portion 42 extends to the extension portion 3 and has a length greater than or equal to the length of the first portion 41.
• the second part 42 has a length greater than or equal to the nominal diameter Dn of the reinforcing bar 2.
• the second portion 42 comprises a first substantially frustoconical portion 42a having its largest base facing towards the first portion 41 of the upset end portion 4, and a second portion 42b substantially frustoconical disposed between the first portion 42a and the extension portion 3, the second portion 42b having its largest base facing the first portion 42a.
• the first portion 42a extends in the extension of the first portion 41
• the second portion 42b extends in the extension of the first portion 42a.
• the second portion 42b has a length greater than or equal to the length of the first portion 42a, and greater than or equal to the length of the first portion 41.
• the end-discharge portion 4 is provided with a cylindrical thread 8 intended to cooperate with a tapping formed in a connecting sleeve, and having a diameter with a bottom thread Df greater than or equal to nominal diameter Dn of the rebar 2.
• the cylindrical threading 8 extends only over part of the length of the upset end portion 4.
• the cylindrical threading 8 extends in part over the first and second portions 42a, 42b of the pushed end portion 4.
• Such a manufacturing method notably comprises the following steps:
• the discharge step is performed cold and at variable speed, for example continuously or in stages.
• the discharge step is successively carried out according to a first delivery mode defining a first speed range and according to a second delivery mode defining a second speed range, the speeds belonging to the second speed range being less than the second speed range. smaller speeds belonging to the first speed range.
• the discharge step consists in forming the second portion 42 'so that it comprises at least a first substantially frustoconical portion 42a having its largest base facing the first portion 41 ', and a second portion substantially' frustoconical 42b 'disposed between the first portion 42a' and the extension portion 3 ', the second portion 42b' having its largest base facing the first portion 42a '.
• first portions 41, 41 'and the first and second portions 42a, 42a', 42b, 42b ' have slightly different lengths, respectively, because the thread 8 has a threaded aperture diameter smaller than the outside diameter. of the first part 41 '.
• a first method of assembling a reinforcement for reinforced concrete is described below with reference mainly to FIGS. 3 and 4.
• This first assembly method also called LSR bond, comprises the following steps:
• first and second reinforcing bars 2, 2 ' each comprising an opposite end portion 10 situated opposite the portion corresponding upset end 4 and provided with a cylindrical thread 1 1, -
• a connecting sleeve 12 having a thread 13 arranged to cooperate with the cylindrical threads 8, 1 1 provided on the end portions 4, 10 of the first and second reinforcing bars 2, 2 ',
• the discharged end portion 4 of the second reinforcing bar 2 ' has a length greater than or substantially equal to the longitudinal length of the tapping 13 provided on the connecting sleeve 12.
• the end portion of the connecting sleeve 12 intended to be turned towards the first reinforcing bar 2 is flared so as to facilitate the insertion of the first reinforcing bar 2 into the connecting sleeve 12.
• a second method of assembling a reinforcement for reinforced concrete is described below with reference mainly to FIGS. 5 and 6.
• This second assembly method also called LCE bonding, further comprises the following steps:
• a stop nut 16 for cooperating on the one hand with the thread 8 provided on the end portion 4 of the second reinforced rebar 2 'and secondly with a second end of the connecting sleeve 12
• the discharged end portion 4 of the second reinforcing bar 2 ' has a length greater than or substantially equal to the sum of the longitudinal length of the tapping 13 provided on the connecting sleeve 12 and the height of the thrust nut 16.
• FIG. 8 represents a reinforcement bar according to a second embodiment of the invention which differs from that represented in FIGS. 1 to 7 essentially in that the cylinder circumscribes the extension portion 3 and has an axis parallel to the longitudinal axis of the extension portion 3 has a smaller diameter than the bottom thread diameter Df of the cylindrical thread 8.
• the projection of the extension portion 3 on a plane orthogonal to the longitudinal axis of the rebar 2 defines a first surface S1 and the projection of the cross-section of the upset end portion 4 at the thread bottom of the cylindrical thread 8 on said plane defines a second surface S2, the first surface S1 being inscribed in the second surface. S2.
• the cross section of the end-end portion 4 at the bottom of the thread of the cylindrical thread 8 is greater than each cross-section of the extension portion 3, and more precisely at each section of the extension portion 3 orthogonal to the longitudinal axis of the extension portion 3.
• the invention is not limited to the sole embodiment of this reinforcing bar, described above as an example, it encompasses all the variants.

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• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Mechanical Engineering (AREA)
• Reinforcement Elements For Buildings (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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ID=49054748

Family Applications (1)

Country Status (4)

Cited By (2)

Citations (5)

Family Cites Families (3)

• 2013
  • 2013-05-29 FR FR1354879A patent/FR3006351B1/fr not_active Expired - Fee Related
• 2014
  • 2014-05-15 WO PCT/FR2014/051125 patent/WO2014191648A1/fr active Application Filing
  • 2014-05-15 EP EP14729702.2A patent/EP3004483B1/fr active Active
  • 2014-05-15 CN CN201480042538.7A patent/CN105473798B/zh active Active

Patent Citations (5)

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