Reinforcement element for load-carrying or load-transferring structural parts and method for fixing said reinforcement element to the surface of a structural part

• US 6,389,775 B1
• Filed: 07/14/2000
• Issued: 05/21/2002
• Est. Priority Date: 12/02/1997
• Status: Expired due to Fees

• Current Assignee: SIKA Schweiz AG (Compagnie de Saint-Gobain SA)
• Original Assignee: Sika AG, vorm. Kaspar Winkler & Co.
• Inventors: Steiner, Werner, Bleibler, Alexander
• Primary Examiner(s): Friedman, Carl D.
• Assistant Examiner(s): KATCHEVES, BASIL S
• Application Number:
  US09/555,748
• Time in Patent Office: 676 Days
• Field of Search: 526/98, 522/231, 523/19, 522/932, 524/22, 527/302, 526/00, 410/104, 410/113, 410/121
• US Class Current: 52/600
• CPC Class Codes: E04G 2023/0251 by using fiber reinforced plastic elements
• CPC Class Codes: E04G 2023/0255 whereby the fiber reinforced plastic elements are stressed
• CPC Class Codes: E04G 2023/0262 Devices specifically adapted for anchoring the fiber reinforced plastic elements, e.g. to avoid peeling off
• CPC Class Codes: E04G 23/0218 Increasing or restoring the load-bearing capacity of building construction elements E04G23/0203 and E04G23/0266 take precedence

Abstract

The invention relates to a reinforcement element (8) for load-carrying or load-transferring structural parts (12). Said reinforcement element has a flat strip segment (100, consisting of a plurality of supporting fibers (26) which are embedded in a binder matrix (28) and are aligned parallel to one another and in the longitudinal direction of the segment. According to the invention, the flat strip segment (10) engages in an anchoring strap (18) with each of its free ends and is secured on said anchoring straps against the tensile and shearing forces exerted in the longitudinal direction of the segment. This enables the flat strip segment (10) can be fixed to a structural part (12) with an impressed pre-stress. The anchoring straps (18) can be anchored on the structural part (12) by means of fixing members (36).

Claims

1. Reinforcing element for load-bearing or load-transmitting structural components (12), comprising a flat strip lamella secured to a structural component outer surface by means of an adhesive layer (16), which flat strip lamella is comprised of a plurality of parallel to each other and parallel to the lamella longitudinal direction oriented reinforcing fibers (26) embedded in a binder matrix (28), wherein

the respective free ends of the flat strip lamella (10) are in engagement with respectively one anchor plate (18) which is anchorable to a construction component (12) or a tension beam by means of securing means (36), which anchor plate protects the lamella against tensile and sheer forces acting upon the lamella in the longitudinal direction,

the anchor plates (18) are elastically bendable and ductile at least in the entry area (42, 44) of the flat strip lamella (10), and

the stiffness in the end section (44) of the anchor plate (18) steadily decreases going towards the entry side (42) of the flat strip lamella.

2. Reinforcing element according to claim 1, wherein the anchor plates (18) are materially engagingly connected with the flat strip lamella ends, preferably by adhesion.

3. Reinforcing element according to claim 1, wherein the anchor plates are engaged with the lamella free ends under force, preferably clamped between two anchor parts (19, 20).

4. Reinforcing element according to claim 1, wherein the anchor plates (18) are form-fittingly connected with the lamella ends.

5. Reinforcing element according to claim 4, wherein the lamella ends respectively exhibit a widening and/or thickening (21) and the anchor plates (18) are provided with a recess (32) for form-fitting reception of the widening and/or thickening (21).

6. Reinforcing element according to claim 1, wherein the anchor plates (18) are comprised of a thin-walled, externally flat floor part (19) and a, compared to the floor part, thick-walled cover part (20).

7. Anchoring element according to claim 6, wherein the anchor plate extends at least over the breadth of the lamella.

8. Anchoring element according to claim 5, wherein the widening and/or thickening (21) is formed by a divergent splitting apart of the reinforcing fibers (26) at the free lamella end.

9. Flat strip lamella according to claim 1, wherein the widening and/or thickening (21) is formed by a widening of the binder matrix (28′

).

10. Reinforcing element according to claim 1, wherein the widening and/or thickening (21) is formed by a material overlay or application preferably of synthetic resin.

11. Flat strip lamella according to claim 1, wherein the anchor plate (18) is formed of two parts.

12. Flat strip lamella according to claim 1, wherein the anchor plates (18) are provided with transverse bore holes (34) for the passage of high-strength securing screws (36).

13. Reinforcing element according to claim 6, wherein the wall thickness and/or the breadth of the cover part (20) and/or the floor part (19) in the end section (44) of the anchor plate (18) towards the entry side (42) of the flat strip lamella declines.

14. Anchoring element according to claim 1, wherein the anchor plates (18) are provided with an anchoring segment (40) adjacent to the end segment (44), which is provided with transverse bore holes (34), sideways beside the secured lamella ends, for passage through of the anchoring screws (36).

15. Anchoring element according to claim 6, wherein the wall thickness of the floor part (19) of the anchoring plate (18) at the entry point (42) corresponds to the layer thickness of the adjoining adhesive layer (16).

16. Anchoring element according to claim 6, wherein the lamella ends are adhered to both the cover part (20) as well as the floor part (19) of the anchor plates (18).

17. Anchoring element according to claim 1, wherein the anchor plates (18) comprise a tube (46) with at least partially flexible, preferably with right-angle internal cross section, and lever elements (48, 50) pressed into the tube (46), and that the respective lamella ends are tensioned between the facing wedge surfaces (52, 54) of the wedge elements (48, 50) and are adhered to these.

19. Anchoring element according to claim 17, wherein the wedge elements (48, 50) are adhered in the tube (46).

20. Anchoring element according to claim 17, wherein the facing wedge surfaces (52, 54) are curved complimentary to each other in the lamella longitudinal direction.

21. Anchoring element according to claim 17, wherein one of the two wedge elements (48) extends only over a part of the tube length and that the other wedge element (50) exhibits a partial surface preferably adjoining tangentially to its wedge surface (54), which holds the flat strip lamella against a structural-component-facing side of the tube wall (56) and such that the flat strip lamella is adhered and/or tensioned with the tube wall and the wedge partial surface.

22. Anchoring element according to claim 17, wherein the tube (46) is a wrapped or wound tube of glass fiber reinforced plastic.

23. Anchoring element according to claim 17, wherein the wedge elements (48, 50) are comprised of glass fiber reinforced plastic.

24. Anchoring element according to claim 17, wherein the tube (46) and the wedge elements (48, 50) are provided with transverse boreholes (34) for the passage through of securing screws (36) along their sides beside the lamella ends.

25. Anchoring element according to claim 17, wherein the tube fitted with the wedge elements (48, 50) have an end section (44) reducing in thickness and/or breadth towards the lamella entry side.

26. Anchoring element according to claim 1, wherein the flat strip lamella is heatable by an electric current.

27. Anchoring element according to claim 26, wherein the anchor plates (18) are electrically conductive and form a contact for connection of the reinforcing fibers, which preferably are comprised of carbon fiber (20), to the electrical current source (22).

28. Anchoring element according to claim 1, wherein at least one of the anchor plates (18) exhibits a shoulder serving as abutment for a tensioning device engaging in the lamella longitudinal direction.

30. Anchoring element according to claim 1, wherein the binder matrix is comprised of a duroplast, preferably of epoxy resin.

31. Anchoring element according to claim 1, wherein the binder matrix is comprised of a thermoplast, preferably selected from the group consisting of polyolefin, vinyl polymer, polyamide, polyester, polyacetate, polycarbonate, and thermoplastic polyurethane.

32. Anchoring element according to claim 1, wherein the reinforcing fibers (26) are comprised of carbon fibers, aramid fibers, glass fibers, and/or polypropylene fibers.

18. A reinforcing element for load-bearing or load-transmitting structural components (12) comprising

a flat strip lamella secured to a structural component outer surface by means of an adhesive layer (16),

wherein the flat strip lamella is comprised of a plurality of parallel to each other and parallel to the lamella longitudinal direction oriented reinforcing fibers (26) embedded in a binder matrix (28),

wherein the flat strip lamella further comprises anchor plates (18) having a tube (46) with at least partially flexible, preferably with right-angle internal cross section, and lever elements (48, 50) pressed into the tube (46), and that the respective lamella ends are tensioned between the facing wedge surfaces (52, 54) of the wedge elements (48, 50) and are adhered to these.

29. A reinforcing element for load-bearing or load-transmitting structural components (12) with a flat strip lamella secured to a structural component outer surface by means of an adhesive layer (16),

wherein the flat strip lamella is comprised of a plurality of parallel to each other and parallel to the lamella longitudinal direction oriented reinforcing fibers (26) embedded in a binder matrix (28), wherein at least one of anchor plates (18) exhibits a shoulder as abutment for a tensioning device engaging in the lamella longitudinal direction.

33. Process for securing a flat strip lamella (10) to the outer surface of a structural component (12), the flat strip lamella comprised of a plurality of reinforcing fibers (26) embedded in a binder matrix (28), parallel to each other and extending in the lamella longitudinal direction, wherein a broad side of the flat strip lamella (10) is pressed against the structural component surface via an adhesive layer (16) applied in a viscous consistency, preferably a reaction or curing resin, and the adhesive layer is hardened with formation of an adhesive bonding, wherein the lamella ends are forced, formed, and/or materially connected with an anchor plate (18), that one of the anchor plates (18) is secured to a structural component and the other anchor plate (18) prior to or after application of the adhesive is engaged with a tensioning mechanism secured to the structural component, and that the flat strip lamella (10) is acted upon with a pull force directed in the lamella longitudinal direction (38) with production of an elastic deformation, and that the flat strip lamella pre-tensioned in this manner is held or pressed against the structural component surface until hardening of the adhesive.

35. A process according to claim 33, wherein an electrical current is conducted through at least a part of the reinforcing fibers (26) for heating the flat strip lamella (10).

36. Process according to claim 33, wherein the lamella ends are widened and/or thickened (21) prior to connecting with the anchor plates (18).

37. A process according to claim 36, wherein the reinforcing fibers (26) at the ends of the previously cut to size flat strip lamellas (10) are freed of the binder matrix (28), preferably using steam, and with the formation of a widening and/or thickening (21) are spread apart and in this condition are fixed with viscous, hardenable binder (28′

).

38. A process according to claim 37, wherein the reinforcing fibers (26) freed of the binder matrix are split apart divergently towards the free lamella ends.

39. A process according to claim 36, wherein the reinforcing fibers (26) freed of binder matrix are introduced into a cut-back recess (32) of the anchor plate (18) and there are positionally fixed and anchored with a binder (28) that is viscous, hardenable, at the same time serves as adhesive.

40. Process according to claim 33, wherein the second anchor plate (18) after achieving a predetermined pre-tension (arrow 38) is secured, preferably by screwing, onto the structural component (12) or the tensioning beam.

34. Process for securing to the outer surface of a structural component (12) a flat strip lamella (10) comprised of a plurality of reinforcing fibers (26) embedded in a binder matrix (28), parallel to each other and extending in the lamella longitudinal direction, wherein a broad side of the flat strip lamella (10) is pressed against the surface of the structural component via an intermediate adhesive layer (16) applied in a viscous consistency, preferably a reaction or curing resin, and wherein the adhesive layer is hardened with formation of an adhesive bonding, wherein the lamella ends are force-, form-, and/or materially-connected with an anchor plate (18), that the anchor plates (18) are first secured to a tension beam with production of an elastic pre-tension in the flat strip lamella (10), that the tension beam is pressed or held with the adhesive side of the flat strip lamella (10) against the structural component outer surface until the adhesive is hardened, and that subsequently the tension beam is removed from the flat strip lamella.