EP2102434A2 - Flexible fiber reinforced composite rebar - Google Patents

Flexible fiber reinforced composite rebar

Info

Publication number
EP2102434A2
EP2102434A2 EP07862985A EP07862985A EP2102434A2 EP 2102434 A2 EP2102434 A2 EP 2102434A2 EP 07862985 A EP07862985 A EP 07862985A EP 07862985 A EP07862985 A EP 07862985A EP 2102434 A2 EP2102434 A2 EP 2102434A2
Authority
EP
European Patent Office
Prior art keywords
bar
set forth
fibers
cross sectional
matrix
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP07862985A
Other languages
German (de)
French (fr)
Other versions
EP2102434A4 (en
Inventor
Brian J. Knouff
Alan Fatz
A. Dean Thompson
William P. Junk
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DT Search and Design LLC
Original Assignee
DT Search and Design LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by DT Search and Design LLC filed Critical DT Search and Design LLC
Publication of EP2102434A2 publication Critical patent/EP2102434A2/en
Publication of EP2102434A4 publication Critical patent/EP2102434A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/07—Reinforcing elements of material other than metal, e.g. of glass, of plastics, or not exclusively made of metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C53/00—Shaping by bending, folding, twisting, straightening or flattening; Apparatus therefor
    • B29C53/14—Twisting

Definitions

  • reinforcing members When concrete is employed as a structural material, it is conventional to incorporate reinforcing members to enhance the tensile strength of the structure.
  • the reinforcing members are usually comprised of a rigid rod or bar, such as a steel rod or bar. Such reinforcing members are typically referred to as "rebar".
  • U. S. Patent No. 6,048,598 to Bryan, III et al. discloses a twisted rope rebar having individual fibers bound to each other by a thermosetting resin.
  • U. S. Patent No. 5,580,642 to Okamoto et al. discloses a reinforcing member comprised of reinforcing fibers and thermoplastic fibers.
  • U. S. Patent Nos. 5,593,536 and 5,626,700 to Kaiser disclose an apparatus for forming reinforcing structural rebar including a combination of pultrusion and SMC (sheet molding compound).
  • the modified pultrusion produces a rebar having a core of thermoset resin reinforcing material and an outer sheet molding compound.
  • U S Patent No. 5,077,113 to Kakihara et al. proposes an inner filament bundle layer spirally wound around a fiber-reinforced core, a plurality of intermediate filament bundles oriented axi ⁇ lly along the core, and an outer filament bundle spirally wound around the core and the other bundles.
  • U. S. Patent No. 4,620,401 to L'Esperance et al. proposes a fiber reinforced thermosetting resin core and a plurality of continuous fibers helically wound around the core and impregnated with the thermosetting resin.
  • the Jackson U. S. Patent No. 2,425,883 discloses a rod or bar formed of fine glass fibers with a phenolic resin cured under heat.
  • the present invention provides an improved composite reinforcement bar or rebar structure.
  • the rebar structure is generally formed by continuous fibers embedded in a thermoplastic resin matrix to form a reinforcement bar.
  • the bar is flattened to achieve a cross sectional aspect ratio greater than one to one.
  • the bar is then twisted in a substantially helical manner.
  • the bar has a substantially elliptical cross sectional shape with a cross sectional aspect ratio of about two to one and a twist pitch of about 30 centimeters.
  • the matrix may be a thermoplastic resin such as polypropylene, and the fibers may be formed of glass.
  • the thermoplastic resin matrix allows the matrix to be softened by the application of heat to thereby bend or flex the bar to desired shapes. The capability of being conveniently bent is also aided by the cross sectional shape and aspect ratio and by the twist applied to the bar. Once bent to a desired shape, the bar is allowed to cool and re-harden to a substantially rigid state.
  • Fig. 1 J s a diagrammatic view of a pultrusion process for forming the flexible fiber reinforced composite rebar of the present invention.
  • Fig. 2 is a fragmentary perspective view of a length of the flexible fiber reinforced composite rebar of the present invention.
  • Fig. 3 is a greatly enlarged cross sectional view of the rebar taken on line 3-3 of Fig. 2.
  • the reference numeral 1 generally designates a flexible fiber reinforced composite reinforcement bar or rebar structure embodying the present invention.
  • the rebar structure 1 generally includes a plurality of reinforcement fibers 2 (Figs. 2 and 3) embedded within a thermoplastic resin matrix 3.
  • the rebar structure 1 is twisted in a generally helical manner.
  • Fig. 1 diagrammatically illustrates system and process 10 for manufacturing the rebar structure 1.
  • the fibers 2 are provided in the form of "ravings" or twisted strands on the spools 14.
  • the fibers 2 may be man made or artificial continuous filaments, such as carbon, glass, aramid, organic and/or metallic fiber.
  • the creel arrangement 12 provides the fibers with optimum pre-tension in order to maximize the impregnation of the polymer 3 into the fibers 2.
  • the particular arrangement of the creel system 12 may vary depending upon the form of the reinforcement/roving 2 provided by the suppliers.
  • the fibers move through a guides 16 which might consist of guide pins and tensioners, depending upon the final size of the end product.
  • the illustrated process 10 includes a dryer 20 into which thermoplastic resin 3 is fed.
  • a heater component 22 heats the thermoplastic resin to a plastic state.
  • a screw “pump” 24 forces the heated resin into the impregnation chamber 18.
  • the impregnation chamber 18, an important component of the process 10, includes two parts.
  • a first part 26 the fibers 2 come into contact with the thermoplastic polymer 3 pumped into the impregnation chamber 18.
  • the design of the chamber 18 enables creation of high shear zones for the thermoplastic polymer 3 that results in significant reduction of the viscosity thereof. This reduction of the viscosity tremendously improves the impregnation of the high viscous polymeric material 3 into the fibers 2.
  • the impregnated fibers 2 are converged into a consolidated impregnated rebar 30. Depending upon the final shape required, the consolidated rebar 30 is given its final shape while it is still hot.
  • the cooler system 32 Once the rebar 30 with its final shape leaves the impregnation chamber 18, it goes through a cooler system 32.
  • the design of the cooler system depends upon the final form of the product.
  • the cooler system 32 might be in the form of a long tube with water sprinklers (not shown) attached along its length. The sprinklers would be used to spray water on the thermoplastic rebar 30 to cool its surface.
  • the impregnated rebar 30 next moves through the puller 36.
  • the puller 36 pulls the impregnated rebar 30 though the entire device throughout the manufacturing process 10.
  • the impregnated rebar enters a cutter station 38, which cuts the final product to its required length.
  • thermoplastic rebar 30 consists of E-glass, or electrical grade glass, as the fiber reinforcement 2 and polypropylene as the thermoplastic matrix 3.
  • the fiber volume ratio is approximately 45% of the total volume of the rebar 30, a representative value for typical long fiber thermoplastic processes.
  • a thermoplastic rebar design optimization was performed using ABAQUSTM finite element analysis software (Dassault Systemes Societe Anonyme France, www.simulia.com).
  • An optimal profile for the rebar 30 was found to be an elliptical cross sectional shape having an aspect ratio of about 2:1, with specific dimensions varying for different rebar sizes.
  • the rebar 30 has a major axis of about 0.75 inch (19.05 mm) and a minor axis of about 0.375 inch (9.53 mm). It is foreseen that the rebar 30 could alternatively have other flattened shapes which are not specifically elliptical. Further, the optimal profile also includes a twist pitch of 30 centimeters (cm) or about one twist per 12 inches of rebar 30. Alternatively, the twist pitch may fall within a range of about 6 to 24 inches (15.24 to 60.96 cm). An example profile is illustrated below in Figure 2, and additional highlights of the design optimization are described below.
  • thermoplastic matrix 3 was chosen over thermoset because a thermoplastic material has the potential for being bendable in the field.
  • One embodiment of the rebar structure incorporates a polypropylene resin as the thermoplastic matrix 3.
  • other thermoplastic resins could be advantageously employed for use in some applications and environments. Bending the rebar 30 may require onsite heating, which will reduce the stresses resulting from the applied bending force. The heating is preferably not of a temperature which would actually melt the thermoplastic material 3, but only to temporarily soften the rebar 30 for bending. The heating temperature may range from about 150 to 200F (65.6 to 93.3 0 C).
  • a rebar structure 1 having an elliptical cross-section with bends along the major axis appears to meet the demands of being bendable in the field.
  • the elliptical shape minimizes transverse stress, while twists allow ease of bending without having to align the rebar.
  • the twist pitch represents the resolution of bend length; that is, if the pitch is 30 cm, the rebar can only be bent every 30 cm. It was determined that increasing the twists in the rebar 30 (that is, decreasing the twist pitch) increases stress and strain values. Of the many twist pitches considered during analysis, the profile which showed the least longitudinal stress was the pitch 30 cm. Further, rebar was found to be optimally bendable in the horizontal to normal plane of the cross section, that is, about the major axis.
  • thermoplastic rebar structure 1 meeting the criteria of bendability in the field yet not requiring alignment included a polypropylene matrix 3 with E-glass fibers 2 at a 45% fiber volume ratio, a substantially elliptical profile with an aspect ratio of about 2:1 , and a twist pitch of about 30 centimeters.

Landscapes

  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Reinforced Plastic Materials (AREA)
  • Moulding By Coating Moulds (AREA)
  • Reinforcement Elements For Buildings (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
  • Laminated Bodies (AREA)

Abstract

A flexible fiber reinforced composite rebar structure includes a plurality of continuous fibers embedded within a thermoplastic resin. The rebar structure has an elliptical cross sectional shape with an aspect ratio of about two to one and a twist with a twist pitch of about 30 cm. The thermoplastic resin matrix enables the rebar structure to be bent in the field by the application of heat to soften the structure and thereafter cooled to return to a rigid state.

Description

FLEXIBLE FIBER REINFORCED COMPOSITE REBAR
Cross-Reference to Related Application
This application claims priority under 35 U. S. C. 119(e) and 37 C.F.R. 1.78(a)(4) based upon copending U. S. Provisional Application, Serial No. 60/874,828 for FLEXIBLE REBAR, filed December 14, 2006, which is incorporated herein by reference.
Background of the Invention
Concrete and other masonry or cementitious materials have high compressive strength but relatively low tensile strength. Thus, when concrete is employed as a structural material, it is conventional to incorporate reinforcing members to enhance the tensile strength of the structure. The reinforcing members are usually comprised of a rigid rod or bar, such as a steel rod or bar. Such reinforcing members are typically referred to as "rebar".
Unfortunately, steel and other metals are susceptible to oxidation. In addition, such materials are quite rigid prior to use so that the placement of such reinforcing members can be difficult and time-intensive. As a result, conventional metal rebar must be cut into pieces and joined in order to form a "criss-cross" or other desired pattern.
One possible solution is to use glass fiber formulations as structural rebar in conjunction with a thermoplastic resin. For example, U. S. Patent No. 6,048,598 to Bryan, III et al. discloses a twisted rope rebar having individual fibers bound to each other by a thermosetting resin. U. S. Patent No. 5,580,642 to Okamoto et al. discloses a reinforcing member comprised of reinforcing fibers and thermoplastic fibers. U. S. Patent Nos. 5,593,536 and 5,626,700 to Kaiser disclose an apparatus for forming reinforcing structural rebar including a combination of pultrusion and SMC (sheet molding compound). The modified pultrusion produces a rebar having a core of thermoset resin reinforcing material and an outer sheet molding compound. U S Patent No. 5,077,113 to Kakihara et al. proposes an inner filament bundle layer spirally wound around a fiber-reinforced core, a plurality of intermediate filament bundles oriented axiεlly along the core, and an outer filament bundle spirally wound around the core and the other bundles. U. S. Patent No. 4,620,401 to L'Esperance et al. proposes a fiber reinforced thermosetting resin core and a plurality of continuous fibers helically wound around the core and impregnated with the thermosetting resin. The Jackson U. S. Patent No. 2,425,883 discloses a rod or bar formed of fine glass fibers with a phenolic resin cured under heat.
Despite these advances, there remains a need to provide an improved structural rebar that overcomes the disadvantages and complexities of the prior art.
Summary of the Invention
The present invention provides an improved composite reinforcement bar or rebar structure. The rebar structure is generally formed by continuous fibers embedded in a thermoplastic resin matrix to form a reinforcement bar. The bar is flattened to achieve a cross sectional aspect ratio greater than one to one. The bar is then twisted in a substantially helical manner. In one embodiment of the rebar structure, the bar has a substantially elliptical cross sectional shape with a cross sectional aspect ratio of about two to one and a twist pitch of about 30 centimeters. The matrix may be a thermoplastic resin such as polypropylene, and the fibers may be formed of glass. The thermoplastic resin matrix allows the matrix to be softened by the application of heat to thereby bend or flex the bar to desired shapes. The capability of being conveniently bent is also aided by the cross sectional shape and aspect ratio and by the twist applied to the bar. Once bent to a desired shape, the bar is allowed to cool and re-harden to a substantially rigid state.
Objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
Brief Description of the Drawings
Fig. 1 Js a diagrammatic view of a pultrusion process for forming the flexible fiber reinforced composite rebar of the present invention.
Fig. 2. is a fragmentary perspective view of a length of the flexible fiber reinforced composite rebar of the present invention.
Fig. 3 is a greatly enlarged cross sectional view of the rebar taken on line 3-3 of Fig. 2. Detailed Description of the Invention
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
Referring now to the drawings in more detail, the reference numeral 1 generally designates a flexible fiber reinforced composite reinforcement bar or rebar structure embodying the present invention. The rebar structure 1 generally includes a plurality of reinforcement fibers 2 (Figs. 2 and 3) embedded within a thermoplastic resin matrix 3. The rebar structure 1 is twisted in a generally helical manner.
Fig. 1 diagrammatically illustrates system and process 10 for manufacturing the rebar structure 1. A creel arrangement 12, including a plurality of spools or bobbins 14 of pays out a plurality of continuous reinforcement fibers 2 into a set of fiber guides 16. The fibers 2 are provided in the form of "ravings" or twisted strands on the spools 14. The fibers 2 may be man made or artificial continuous filaments, such as carbon, glass, aramid, organic and/or metallic fiber. The creel arrangement 12 provides the fibers with optimum pre-tension in order to maximize the impregnation of the polymer 3 into the fibers 2. The particular arrangement of the creel system 12 may vary depending upon the form of the reinforcement/roving 2 provided by the suppliers.
The fibers move through a guides 16 which might consist of guide pins and tensioners, depending upon the final size of the end product. The guides 16, apart from guiding the path of the fibers 2, helps increase the surface area of the within a matrix impregnation chamber 18. The illustrated process 10 includes a dryer 20 into which thermoplastic resin 3 is fed. A heater component 22 heats the thermoplastic resin to a plastic state. A screw "pump" 24 forces the heated resin into the impregnation chamber 18.
The impregnation chamber 18, an important component of the process 10, includes two parts. In a first part 26, the fibers 2 come into contact with the thermoplastic polymer 3 pumped into the impregnation chamber 18. The design of the chamber 18 enables creation of high shear zones for the thermoplastic polymer 3 that results in significant reduction of the viscosity thereof. This reduction of the viscosity tremendously improves the impregnation of the high viscous polymeric material 3 into the fibers 2. In a second part 28 of the impregnation chamber 18, the impregnated fibers 2 are converged into a consolidated impregnated rebar 30. Depending upon the final shape required, the consolidated rebar 30 is given its final shape while it is still hot.
Once the rebar 30 with its final shape leaves the impregnation chamber 18, it goes through a cooler system 32. The design of the cooler system depends upon the final form of the product. For thermoplastic rebar 30, the cooler system 32 might be in the form of a long tube with water sprinklers (not shown) attached along its length. The sprinklers would be used to spray water on the thermoplastic rebar 30 to cool its surface.
The impregnated rebar 30 next moves through the puller 36. The puller 36 pulls the impregnated rebar 30 though the entire device throughout the manufacturing process 10. Finally, the impregnated rebar enters a cutter station 38, which cuts the final product to its required length.
One embodiment thermoplastic rebar 30 consists of E-glass, or electrical grade glass, as the fiber reinforcement 2 and polypropylene as the thermoplastic matrix 3. The fiber volume ratio is approximately 45% of the total volume of the rebar 30, a representative value for typical long fiber thermoplastic processes. A thermoplastic rebar design optimization was performed using ABAQUS™ finite element analysis software (Dassault Systemes Societe Anonyme France, www.simulia.com). An optimal profile for the rebar 30 was found to be an elliptical cross sectional shape having an aspect ratio of about 2:1, with specific dimensions varying for different rebar sizes. In one embodiment, the rebar 30 has a major axis of about 0.75 inch (19.05 mm) and a minor axis of about 0.375 inch (9.53 mm). It is foreseen that the rebar 30 could alternatively have other flattened shapes which are not specifically elliptical. Further, the optimal profile also includes a twist pitch of 30 centimeters (cm) or about one twist per 12 inches of rebar 30. Alternatively, the twist pitch may fall within a range of about 6 to 24 inches (15.24 to 60.96 cm). An example profile is illustrated below in Figure 2, and additional highlights of the design optimization are described below.
A thermoplastic matrix 3 was chosen over thermoset because a thermoplastic material has the potential for being bendable in the field. One embodiment of the rebar structure incorporates a polypropylene resin as the thermoplastic matrix 3. However, it is foreseen that other thermoplastic resins could be advantageously employed for use in some applications and environments. Bending the rebar 30 may require onsite heating, which will reduce the stresses resulting from the applied bending force. The heating is preferably not of a temperature which would actually melt the thermoplastic material 3, but only to temporarily soften the rebar 30 for bending. The heating temperature may range from about 150 to 200F (65.6 to 93.30C).
A rebar structure 1 having an elliptical cross-section with bends along the major axis appears to meet the demands of being bendable in the field. The elliptical shape minimizes transverse stress, while twists allow ease of bending without having to align the rebar. The twist pitch represents the resolution of bend length; that is, if the pitch is 30 cm, the rebar can only be bent every 30 cm. It was determined that increasing the twists in the rebar 30 (that is, decreasing the twist pitch) increases stress and strain values. Of the many twist pitches considered during analysis, the profile which showed the least longitudinal stress was the pitch 30 cm. Further, rebar was found to be optimally bendable in the horizontal to normal plane of the cross section, that is, about the major axis.
Various aspect ratios were also considered during analysis. It was found that increasing the aspect ratio reduced the longitudinal stress, but increased the transverse stress. Increasing the aspect ratio also increased the likelihood for buckling. An aspect ratio of 2:1 was identified as the optimal design parameter, and is illustrated in Figure 3 below.
In summary, an optimized embodiment of the thermoplastic rebar structure 1 meeting the criteria of bendability in the field yet not requiring alignment included a polypropylene matrix 3 with E-glass fibers 2 at a 45% fiber volume ratio, a substantially elliptical profile with an aspect ratio of about 2:1 , and a twist pitch of about 30 centimeters.
It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.

Claims

C L A I M SWhat is claimed and desired to be secured by Letters Patent is:
1. A composite reinforcement bar structure comprising:
(a) a thermoplastic resin matrix;
(b) a plurality of elongated fibers embedded in said matrix to form a reinforcement bar; and
(c) said bar having a flattened cross sectional shape.
2. A structure as set forth in Claim 1 wherein: (a) said bar has a helical twist.
3. A structure as set forth in Claim 1 wherein:
(a) said bar has a helical twist with a twist pitch ranging from about 6 to 24 inches (15.24 to 60.96 cm).
4. A structure as set forth in Claim 1 wherein:
(a) said bar has a helical twist with a twist pitch of about 30 cm.
5. A structure as set forth in Claim 1 wherein:
(a) said bar has a cross sectional aspect ratio of about two to one.
6. A structure as set forth in Claim 1 wherein:
(a) said bar has a substantially elliptical cross sectional shape.
7. A structure as set forth in Claim 1 wherein:
(a) said bar has a substantially elliptical cross sectional shape with a cross sectional aspect ratio of about two to one. A structure as set forth in Claim 1 wherein: (a) said thermoplastic resin matrix is formed of a polypropylene resin.
8. A structure as set forth in Claim 1 wherein:
(a) said fibers are formed from one of a group of materials consisting of glass, carbon, aramid, and metal.
9. A structure as set forth in Claim 1 wherein: (a) said fibers are formed of glass.
10. A structure as set forth in Claim 1 wherein:
(a) said fibers form approximately 45 per cent of a volume of said bar.
11. A composite reinforcement bar structure comprising:
(a) a thermoplastic resin matrix;
(b) a plurality of continuous fibers embedded in said matrix to form a reinforcement bar;
(c) said bar having a substantially elliptical cross sectional shape; and
(d) said bar having a helical twist.
12. A structure as set forth in Claim 12 wherein:
(a) said bar has a helical twist with a twist pitch ranging from about 6 to 24 inches (15.24 to 60.96 cm).
13. A structure as set forth in Claim 12 wherein:
(a) said bar has a helical twist with a twist pitch of about 30 cm.
14. A structure as set forth in Claim 12 wherein:
(a) said bar has a cross sectional aspect ratio of about two to one.
15. A structure as set forth in Claim 12 wherein:
(a) said thermoplastic resin matrix is formed of a polypropylene resin.
16. A structure as set forth in Claim 12 wherein:
(a) said fibers are formed from one of a group of materials consisting of glass, carbon, aramid, and metal.
17. A structure as set forth in Claim 12 wherein: (a) said fibers are formed of glass.
18. A structure as set forth in Claim 12 wherein:
(a) said fibers form approximately 45 per cent of a volume of said bar.
19. A composite reinforcement bar structure comprising:
(a) a thermoplastic resin matrix;
(b) a plurality of continuous fibers embedded in said matrix to form a reinforcement bar, said fibers being formed from one of a group of materials consisting of glass, carbon, aramid, and metal;
(c) said bar having a substantially elliptical cross sectional shape with a cross sectional aspect ratio of about two to one;
(d) said bar having a helical twist with a twist pitch ranging from about 6 to 24 inches (15.24 to 60.96 cm).
20. A structure as set forth in Claim 20 wherein:
(a) said bar has a twist pitch of about 30 cm.
21. A structure as set forth in Claim 20 wherein:
(a) said thermoplastic resin matrix is formed of a polypropylene resin.
22. A structure as set forth in Claim 20 wherein: (a) said fibers are formed of glass.
23. A structure as set forth in Claim 20 wherein:
(a) said fibers form approximately 45 per cent of a volume of said bar.
24. In a process for forming a composite reinforcement bar structure including a plurality of elongated fibers embedded in a polymeric matrix, the improvement comprising the steps of:
(a) providing a thermoplastic resin to form said polymeric matrix;
(b) embedding said elongated fibers within said matrix to form a ( reinforcement bar;
(c) flattening said reinforcement bar to result in a cross sectional aspect ratio greater than one to one; and
(d) twisting the flattened bar to achieve a twist pitch ranging from about 6 to 24 inches (15.24 to 60.96 cm).
25. A process as set forth in Claim 25 wherein said flattening step includes the step of:
(a) flattening said bar to result in a substantially elliptical cross sectional shape having an aspect ratio of about two to one.
26. A process as set forth in Claim 25 wherein said twisting step includes the step of: (a) twisting the flattened bar to achieve a twist pitch of about 30 cm.
EP07862985A 2006-12-14 2007-12-14 Flexible fiber reinforced composite rebar Withdrawn EP2102434A4 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US87482806P 2006-12-14 2006-12-14
US11/955,637 US20080141614A1 (en) 2006-12-14 2007-12-13 Flexible fiber reinforced composite rebar
PCT/US2007/025711 WO2008076400A2 (en) 2006-12-14 2007-12-14 Flexible fiber reinforced composite rebar

Publications (2)

Publication Number Publication Date
EP2102434A2 true EP2102434A2 (en) 2009-09-23
EP2102434A4 EP2102434A4 (en) 2009-11-25

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EP07862985A Withdrawn EP2102434A4 (en) 2006-12-14 2007-12-14 Flexible fiber reinforced composite rebar

Country Status (6)

Country Link
US (1) US20080141614A1 (en)
EP (1) EP2102434A4 (en)
JP (1) JP2010513751A (en)
AU (1) AU2007334387A1 (en)
CA (1) CA2671371A1 (en)
WO (1) WO2008076400A2 (en)

Families Citing this family (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011002796A1 (en) * 2011-01-17 2012-07-19 Sgl Carbon Se Carrier element for receiving in a train or Lastträgergurt
WO2012142098A2 (en) 2011-04-12 2012-10-18 Ticona Llc Umbilical for use in subsea applications
CN103858181B (en) 2011-04-12 2016-03-30 提克纳有限责任公司 For the composite core of electrical transmission cable
JP6276686B2 (en) 2011-04-12 2018-02-07 ティコナ・エルエルシー Die and method for impregnating fiber roving
WO2012142129A1 (en) 2011-04-12 2012-10-18 Daniel Allan Electrical transmission cables with composite cores
EP2697041B1 (en) 2011-04-12 2018-10-17 Ticona LLC Impregnation section of die and method for impregnating fiber rovings
JP2014516822A (en) 2011-04-12 2014-07-17 ティコナ・エルエルシー Thermoplastic rod reinforced with continuous fiber and extrusion process for its production
CA2775445C (en) 2011-04-29 2019-04-09 Ticona Llc Die and method for impregnating fiber rovings
CA2775442C (en) 2011-04-29 2019-01-08 Ticona Llc Impregnation section with upstream surface and method for impregnating fiber rovings
WO2012149127A1 (en) 2011-04-29 2012-11-01 Ticona Llc Die with flow diffusing gate passage and method for impregnating fiber rovings
CA2746281A1 (en) * 2011-07-14 2013-01-14 Pultrall Inc. Curved reinforcement rod having improved strength in the curvature and the method to procuce the rod
US10336016B2 (en) 2011-07-22 2019-07-02 Ticona Llc Extruder and method for producing high fiber density resin structures
WO2013086269A1 (en) 2011-12-09 2013-06-13 Ticona Llc Impregnation section of die for impregnating fiber rovings
US9283708B2 (en) 2011-12-09 2016-03-15 Ticona Llc Impregnation section for impregnating fiber rovings
US9409355B2 (en) 2011-12-09 2016-08-09 Ticona Llc System and method for impregnating fiber rovings
CN108192278B (en) 2011-12-09 2020-12-29 提克纳有限责任公司 Asymmetric fiber reinforced polymer tapes
CN103987514B (en) 2011-12-09 2016-10-12 提克纳有限责任公司 For impregnating the dipping section of the mould of fiber roving
CA2773042A1 (en) 2012-03-23 2013-09-23 Pultrall Inc. Curved rod with improved mechanical resistance on its curve and production method therefof
WO2013188644A1 (en) 2012-06-15 2013-12-19 Ticona Llc Subsea pipe section with reinforcement layer
DE102015100386A1 (en) * 2015-01-13 2016-07-14 Technische Universität Dresden Reinforcing rod of filament composite and method for its production
US10036165B1 (en) * 2015-03-12 2018-07-31 Global Energy Sciences, Llc Continuous glass fiber reinforcement for concrete containment cages
DK178510B1 (en) * 2015-03-31 2016-04-18 Fiberline Composites As Semi-finished and structural element made from the same
US10480320B2 (en) * 2017-03-06 2019-11-19 Minova International Limited Oval bar
DE102017107948A1 (en) * 2017-04-12 2018-10-18 Technische Universität Dresden Reinforcing bar for insertion into a concrete matrix and its production method, a reinforcement system consisting of several reinforcing bars and a concrete component
DE102017120143A1 (en) * 2017-09-01 2019-03-07 Groz-Beckert Kg Bending method and bending device for bending a composite rod
DE102017219774B4 (en) 2017-11-07 2024-11-14 Leichtbau-Zentrum Sachsen Gmbh Method and system for the production of fiber-matrix composite profiles with axially rotating cross-section and adjustable fiber orientation, as well as use of a corresponding method and system
CA3116064A1 (en) 2018-11-19 2020-05-28 Shoujie Li Composite rebar
CN113370559B (en) * 2020-07-22 2022-06-10 江苏易鼎复合技术有限公司 Continuous linear resin-based fiber reinforced prepreg
JP2023062721A (en) * 2021-10-22 2023-05-09 学校法人金沢工業大学 Concrete reinforcement composite material and concrete reinforcing bar
DE102023203726A1 (en) * 2023-04-24 2024-10-24 Sgl Carbon Se REINFORCEMENT UNIT

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2425883A (en) * 1941-08-08 1947-08-19 John G Jackson Concrete structural element reinforced with glass filaments
GB611492A (en) * 1946-05-02 1948-10-29 John Lloyd Bannister Improvements in reinforcing bars
FR1068604A (en) * 1949-12-10 1954-06-29 Concrete reinforcement
US4376834A (en) * 1981-10-14 1983-03-15 The Upjohn Company Polyurethane prepared by reaction of an organic polyisocyanate, a chain extender and an isocyanate-reactive material of m.w. 500-20,000 characterized by the use of only 2-25 percent by weight of the latter material
CA1238205A (en) * 1985-04-26 1988-06-21 Cerminco Inc. Structural rod for reinforcing concrete material
JPH0718206B2 (en) * 1989-09-14 1995-03-01 帝人株式会社 Method of manufacturing structural rod
JPH05269726A (en) * 1992-03-25 1993-10-19 Mitsui Constr Co Ltd Reinforcing material for structure of civil engineering structure
JPH10506584A (en) * 1994-06-28 1998-06-30 マーシャル・インダストリーズ・コンポジッツ Molding equipment for building structure reinforcing bars
US5650220A (en) * 1995-05-26 1997-07-22 Owens-Corning Fiberglas Technology, Inc. Formable reinforcing bar and method for making same
US5727357A (en) * 1996-05-22 1998-03-17 Owens-Corning Fiberglas Technology, Inc. Composite reinforcement
US5891560A (en) * 1997-07-02 1999-04-06 The Dow Chemical Company Fiber-reinforced composite and method of making same
US6048598A (en) * 1997-12-17 2000-04-11 Balaba Concrete Supply, Inc. Composite reinforcing member
AU2771001A (en) * 2000-01-13 2001-07-24 Avc Holdings Inc. Reinforcing bars for concrete structures
DE10108357A1 (en) * 2001-02-21 2002-08-29 Sika Ag, Vorm. Kaspar Winkler & Co Reinforcing bar and method for its production

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JP2010513751A (en) 2010-04-30
AU2007334387A1 (en) 2008-06-26
WO2008076400A3 (en) 2008-10-09
US20080141614A1 (en) 2008-06-19
WO2008076400A2 (en) 2008-06-26
CA2671371A1 (en) 2008-06-26

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