REINFORCING BODY AND METHOD FOR ITS MANUFACTURING

Abstract

A reinforcing body and a method for its manufacturing. The reinforcing body has at least one reinforcing bar. Each reinforcing bar has a core with a peripheral surface at which a rib structure with at least one rib and at least one depression is provided. The core is formed by at least one first fiber strand embedded in a core matrix. For creating the at least one rib at least one second fiber strand is embedded into a rib matrix, wherein the at least one second fiber strand and the rib matrix are separated by at least one depression in a direction parallel to a longitudinal center axis of the reinforcing bar, such that the at least one second fiber strand is separated into fiber strand sections. The at least one first and the at least one second fiber strand have fibers of different materials.

Claims

1. A reinforcing body (10), comprising: at least one reinforcing bar (11) that extends in an axial direction along a longitudinal center axis (A) that has a core (17) and a rib structure (18) arranged at a peripheral surface (20) of the core (17) having at least one rib (19) and at least one depression (22), wherein the core (17) comprises at least one first fiber strand (14) of first fibers (26) embedded in a core matrix (27), wherein at least one second fiber strand (25) of second fibers (28) embedded in a rib matrix (29) is divided into a plurality of fiber strand sections (25a), wherein fiber strand sections (25a) of the at least one second fiber strand (25) that are directly adjacent in the axial direction are separated from each other by the at least one depression (22) and each fiber strand section (25a) is arranged in a rib (19) or a rib portion of the at least one rib (19), wherein the fiber strand sections (25a) of the at least one second fiber strand (25) extend in the axial direction at least in straight extending sections of the reinforcing bar (11), and wherein the second fibers (28) of the at least one second fiber strand (25) are made of a fiber material that is different from a fiber material of the first fibers (26).

2. The reinforcing body according to claim 1, wherein the first fibers (26) of the first fiber strand (24) are oriented mainly parallel to the longitudinal center axis (A) of the reinforcing bar (11) in straight extending sections of the reinforcing bar (11).

3. The reinforcing body according to claim 1, wherein the second fibers (28) of the fiber strand sections (25a) of the second fiber strand (25) are oriented mainly parallel to the longitudinal center axis (A) of the reinforcing bar (11) in straight extending sections of the reinforcing bar (11).

4. The reinforcing body according to claim 1, wherein the fiber material of the first fibers (26) has a higher tensile strength than the fiber material of the second fibers (28).

5. The reinforcing body according to claim 1, wherein the first fibers (26) contain carbon or AR-glass or consist of carbon or AR-glass.

6. The reinforcing body according to claim 1, wherein the second fibers (28) comprise glass or polymer material or consist of glass or polymer material.

7. The reinforcing body according to claim 1, wherein at least one of the core matrix (27) of the reinforcing bar (11) and the rib matrix (29) of the at least one rib (19) includes a uniform matrix material (M, M2).

8. The reinforcing body according to claim 7, wherein the core matrix (27) of the reinforcing bar (11) and the rib matrix (29) of the at least one rib (19) include the same matrix material (M).

9. A method for manufacturing a reinforcing body (10) comprising the following steps: manufacturing a reinforcing bar blank (11a) comprising a core (17) and a coating layer (32) surrounding a peripheral surface (20) of the core (17), wherein the core (17) comprises first fibers (26) of a fiber material embedded in a core matrix (27), and wherein the coating layer (32) comprises second fibers (28) of a different fiber material embedded in a matrix of the coating layer (32), introducing at least one depression (22) in the coating layer (32) of the reinforcing bar blank (11a) for creating a rib structure (18) with at least one rib (19) and at least one depression (22), in order to obtain a reinforcing bar (11), manufacturing the reinforcing body using the at least one reinforcing bar (11).

10. The method according to claim 9, wherein the at least one depression (22) extends in a peripheral direction around a longitudinal center axis (A) of the reinforcing bar (11).

11. The method according to claim 9, wherein the at least one depression (22) extends helically around a longitudinal center axis (A) of the reinforcing bar (11).

12. The method according to claim 9, wherein the at least one depression (22) has the shape of a groove.

13. The method according to claim 9, wherein the at least one depression (22) is arranged completely outside of the core (17).

14. The method according to claim 13, wherein the at least one depression (22) extends to the peripheral surface (20) of the core (17).

15. The reinforcing body according to claim 1, wherein the second fibers (28) are cheaper than the first fibers (26).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Preferred embodiments of the invention are derived from the dependent claims, the description and the drawings. In the following preferred embodiments of the invention are explained in detail with reference to the attached drawings. The drawings show:

[0039] FIGS. 1-4 a schematic illustration of an embodiment of a reinforcing body in the form of a reinforcing bar respectively,

[0040] FIG. 5 a cross-section of a reinforcing bar blank with a core and a coating layer that surrounds the peripheral surface of the core during the manufacturing of a reinforcing body.

[0041] FIGS. 6 and 7 a reinforcing bar manufactured based on the reinforcing bar blank of FIG. 5 respectively, wherein at least one groove or depression was inserted into the coating layer,

[0042] FIGS. 8 and 9 a cross-section view through an embodiment of a reinforcing bar respectively according to the cutting line Q-Q in FIG. 6,

[0043] FIGS. 10 and 11 different conditions during the manufacturing of a reinforcing body according to an exemplary non-inventive method and

[0044] FIGS. 12-15 schematic illustrations of embodiments of construction material bodies, each having a construction material matrix in which a reinforcing body is embedded respectively.

DETAILED DESCRIPTION

[0045] In FIGS. 1-4 different embodiments of reinforcing bodies 10 that are configured as reinforcing bar 11 respectively, are schematically illustrated. A reinforcing bar 11 can extend straight along a longitudinal center axis A. The reinforcing bar 11 can in modification to the illustrated embodiments also comprise one or more bending locations or corner locations.

[0046] In the simplest case a reinforcing body 10 is formed by one single reinforcing bar 11. In other embodiments a plurality of reinforcing bars 11 can form one reinforcing body 10, e.g. a reinforcing grid 12 for reinforcing a construction material body 13 (FIGS. 12-15). The construction material body 13 comprises a construction material matrix B of concrete or mortar. The reinforcing body 10 or the reinforcing grid 12 is embodied in the construction material matrix B in order to support tensile forces acting on the construction material body 13. In doing so, the reinforcing grid 12 can extend mainly parallel to one plane as it is exemplarily illustrated in FIGS. 12 and 13. Alternatively thereto, the reinforcing grid 12 can also comprise at least one bending or corner location as it is schematically illustrated in FIGS. 14 and 15. Finally any two-dimensional or three-dimensional reinforcing body 10 can be formed, as it is required or suitable for reinforcing a respective construction material body 13 by using one reinforcing bar 11 or a plurality of reinforcing bars 11.

[0047] The reinforcing body 10 accordingly comprises one reinforcing bar 11 or a plurality of reinforcing bars 11. Each reinforcing bar 11 has a core 17 and a rib structure 18 with at least one rib 19. The at least one rib 19 extends from a peripheral surface 20 of the core 17 inclined or orthogonal to the longitudinal center axis A outwardly. The cross-sectional form of the at least one rib 19 can have different configurations. In the embodiments shown in FIGS. 1 and 4 the at least one rib 19 has a mainly rectangular cross-section. In the embodiments shown in FIGS. 2 and 3 the at least one rib 19 haswith view from outside onto the reinforcing bar 11a convex curved rib outer surface 21 that adjoins the peripheral surface 20.

[0048] The at least one rib 19 can extend helically around the longitudinal center axis A along the peripheral surface 20 (FIGS. 1-3). In these embodiments with a helical rib 19 one single helical rib 19 is illustrated as an example. In other embodiments a plurality of helical ribs 19 can be present that extend without crossing or with crossing along the peripheral surface 20.

[0049] In FIG. 4 an alternative embodiment with ring-shaped and for example circular ring-shaped ribs 19 is illustrated that are arranged with distance to each other in the direction parallel to the longitudinal center axis A.

[0050] Between two directly adjacent arranged ribs 19 of the rib structure 18 or between two directly adjacent arranged rib portions or rib sections of a single helical rib 19 a groove-shaped depression 22 is formed respectively. With one single helical rib 19 the groove-shaped depression 22 is helical and created due to the pitch of the helical rib 19, wherein the pitch depends on the radius or diameter of the core 17 and the slope of the helical rib 19. Preferably the pitch and/or the slope of a helical rib 19 are constant.

[0051] A cross-section through a reinforcing bar 11 is illustrated in FIGS. 8 and 9 respectively. The cross-section extends through the core 17 as well as through a ring-shaped rib 19 along the cutting line Q-Q in FIG. 6 according to the example. As it can be seen in FIGS. 8 and 9, the core 17 consists of at least one first fiber strand 24 with first fibers 26 that are embedded in a matrix material M of a core matrix 27. The at least one first fiber strand 24 is an endless fiber strand, e.g. a roving. The first fibers 26 consist of carbon or AR-glass according to the embodiment. Epoxy resin, vinylester, polyurethane, polyethylene, polystyrene, a polysiloxane or acrylate can be used as matrix material M for the core matrix 27.

[0052] The rib structure comprises at least one rib 19 and at least one depression 22. The at least one rib 19 consists of at least one second fiber strand 25 of second fibers 28 that was divided or separated into a plurality of fiber strand sections 25a. The second fiber strand sections 25a are embedded into a matrix material M of a rib matrix 29. The matrix material M of the rib matrix 29 is the same as the matrix material M for the core matrix 27 according to the embodiment of FIG. 8.

[0053] The fiber material of the second fibers 28 is different from the fiber material of the first fibers 26. The fiber material for the second fibers 28 can be, e.g. E-glass, ECR-glass, AR-glass, basalt or polypropylene.

[0054] In all embodiments the reinforcing bar 11 or the reinforcing body 10 made of at least one reinforcing bar 11 is free from metallic materials.

[0055] In a modified embodiment according to FIG. 9 the core matrix 27 consists of a first matrix material M1 and the rib matrix 29 consists of a second matrix material M2 that is different from the first matrix material M1.

[0056] The at least one first fiber strand 24 extends in axial direction along the longitudinal center axis A. At the locations, at which the reinforcing bar 11 comprises a bend or corner, individual first fibers 26 have different bending radii or radii of curvature. At least in the sections, in which the reinforcing bar 11 extends straight, the first fibers 26 can be mainly orientated in axial direction, wherein technically unavoidable bendings or ondulations of the first fibers 26 can be present. The better the stretching of the first fibers 26 of the at least one first fiber strand 24 is, the better the supportability of tensile forces.

[0057] The load carrying capacity of the reinforcing bar 11 is defined by the core 17. The rib structure 18 with the fiber strand sections 25a of the second fiber strand 25 embedded in the rib matrix 29 does not contribute to the increase of the tensile load carrying capacity of the reinforcing bar 11. Rather the rib structure 18 is configured to couple the reinforcing bar 11 in the construction material matrix B of the construction material body 13. For this reason the rib structure 18 is mainly configured to support shear stress.

[0058] Because at least one groove-like depression 22 is created in the rib structure 18, the at least one rib 19 has a rib width x in direction parallel to the longitudinal center axis A, that is about orders smaller than the length of the core 17 along the longitudinal center axis A. A depression with y corresponds to the minimum distance between two directly adjacent ribs 19 or rib sections or rib portions of a helical rib 19 in axial direction.

[0059] In one embodiment, particularly an embodiment in which the at least one depression 22 is created due to material removal, the rib width x can have an amount of at least 1 mm or 2 mm or 5 mm (FIG. 6). The depression width y can have an amount of, e.g. 0.5-10 mm and particularly 1-6 mm.

[0060] In one example that does not correspond to the invention and in which the at least one rib 19 is created, due to a material application onto the core 17, dimensions are typically remarkably different: The depression with y can have an amount of at least 1 mm or 2 mm or 5 mm (FIG. 6). The rib width x can have an amount of 0.5-10 mm and particularly 1-6 mm for example.

[0061] In the illustrated preferred embodiments the at least one second fiber strand 25 extends mainly parallel to the first fiber strand 24. At each location in peripheral direction around the longitudinal center axis A the directly adjacent fiber strand sections 25a separated by a depression 22 are at least mainly aligned. For the second fibers 28 of the fiber strand sections 25a it applies analog to the first fibers 26 that apart from technically necessary ondulations, they extend stretched as far as possible. At bending or corner locations of the reinforcing bar 11 the second fibers 28 can deviate from the parallelism to the longitudinal center axis A, because at such bending or corner locations of the reinforcing bar 11 different bending radii of the reinforcing bar 11 occur radial inward and radial outward.

[0062] As it is illustrated in FIGS. 6 and 7, the rib width x is small compared with the length of the core 17 and/or the length of the at least one first fiber strand 24 in the core 17. In doing so, different fiber materials can be used for the first fibers 26 and the second fibers 28 that have coefficients of thermal expansion that are remarkably different. For example a combination of first fibers 26 of carbon and second fibers 28 of glass can be used. The different length variations of the second fibers 28 compared with the first fibers 26 have no or at least a non-remarkable influence on the reinforcing bar 11. Internal stress that could impact the tensile strength of the reinforcing bar 11 or the reinforcing body 10 can be at least reduced in this way.

[0063] Based on the illustrations in FIGS. 5-7, a preferred method for manufacturing the reinforcing body 10 with at least one reinforcing bar 11 is illustrated. First a reinforcing bar blank 11a is manufactured that is an intermediate product during the manufacturing process so to speak. The reinforcing bar blank 11a can be manufactured, for example, by a pultrusion method and comprises a core 17 with the at least one first fiber strand 24 embedded in the core matrix 27 as well as a coating layer 32 that is directly arranged on the peripheral surface 20 of the core 17 and completely covers the peripheral surface 20 according to the example. The coating layer 32 has a hollow cylindrical configuration according to the embodiment.

[0064] The coating layer 32 is formed by a matrix material, in which the second fibers 28 are embedded. The at least one second fiber strand 25 extends in the coating layer 32 parallel to the at least one first fiber strand 24 in the core 17. The matrix material of the coating layer 32 corresponds to the matrix material of the rib matrix 29. The coating layer 32 forms the basis for manufacturing the rib structure 18. A layer thickness d of the coating layer 32 predefines the maximum height h of a rib 19 to be manufactured radial or orthogonal to the longitudinal center axis A (FIG. 5).

[0065] For creating the rib structure 28 with the at least one rib 19 at least one groove-shaped depression 22 is introduced into the coating layer 32 (FIGS. 6 and 7). The depression 22 is open to the side opposite to the core 17. In direction parallel to the longitudinal center axis A the at least one depression 22 is limited by two opposite side walls 33. The side walls 33 thus form opposite groove flanks so to speak. The two side walls 33 are connected with each other by a bottom 34 of the depression 22. The bottom 34 forms the ground of the groove. The bottom 34 can be formed by a section of the peripheral surface 20 of the core 17 (FIGS. 1-4 and 6).

[0066] Alternatively a tier 32a or a section of the coating layer 32 can remain at the peripheral surface 20, such that the bottom 34 is formed by the tier 32a (FIG. 7). The thickness s of the tier 32a has an amount of preferably at most 50% of the layer thickness d of the coating layer 32 or the height h of the at least one rib 19.

[0067] The at least one depression 22 introduced into the coating layer 32 of the reinforcing bar blank 11a is arranged completely outside of the core 17 and can extend partly (FIG. 7) or completely (FIG. 6) through the coating layer 32 according to the preferred embodiments. Depending therefrom the bottom 34 is formed by a section of the peripheral surface 20 (FIG. 6) or by not removed material of the coating layer 32 (FIG. 7). The maximum depth of the introduced at least one depression 22 is equal to the layer thickness d of the coating layer 32. In doing so, it is guaranteed that when introducing the at least one depression 22 the first fibers 26 in the core 17 remain undamaged and the maximum tensile strength provided by the reinforcing bar 11 is not negatively influenced when creating the rib structure 18.

[0068] In FIGS. 10 and 11 an alternative manufacturing method for manufacturing of a reinforcing bar 11 is illustrated. In doing so, the core 17 is manufactured first, e.g. by means of a pultrusion method. Subsequently, at least one fiber strand 35 with second fibers 28 embedded in a matrix material can be applied on the peripheral surface 20 and can be attached there, particularly by means of a material bond connection, e.g. due to hardening of the matrix material of the fiber strand 35 and/or the core 17. In FIG. 11 the manufacturing of a reinforcing bar 11 with one single helical rib 19 is illustrated. In modification hereto reinforcing bars 11 with a plurality of ribs 19 can be manufactured by winding a plurality of fiber strands 35 ring-shaped and/or helically around the core 17 respectively.

[0069] The invention refers to a reinforcing body 10 and a method for its manufacturing. The reinforcing body 10 has at least one reinforcing bar 11. Each reinforcing bar 11 has a core 17 with a peripheral surface 20 at which a rib structure 18 with at least one rib 19 and at least one depression 22 is provided. The core 17 is formed by at least one first fiber strand 24 embedded in a core matrix 27. For creating the at least one rib 19 at least one second fiber strand 25 is embedded into a rib matrix 29, wherein the at least one second fiber strand 25 and the rib matrix 29 are separated by at least one depression 22 in a direction parallel to a longitudinal center axis A of the reinforcing bar 11, such that the at least one second fiber strand 25 is separated into fiber strand sections 25a. The at least one first and the at least one second fiber strand 24, 25 have fibers 26 or 28 of different materials.

LIST OF REFERENCE SIGNS

[0070] 10 reinforcing body [0071] 11 reinforcing bar [0072] 11a reinforcing bar blank [0073] 12 reinforcing grid [0074] 13 construction material body [0075] 17 core [0076] 18 rib structure [0077] 19 rib [0078] 20 peripheral surface of the core [0079] 21 rib outer surface [0080] 22 depression [0081] 24 first fiber strand [0082] 25 second fiber strand [0083] 25a fiber strand section of the second fiber strand [0084] 26 first fibers [0085] 27 core matrix [0086] 28 second fibers [0087] 29 rib matrix [0088] 32 coating layer [0089] 32a tier of the coating layer [0090] 33 side wall [0091] 34 bottom [0092] 35 fiber strand [0093] A longitudinal center axis [0094] B construction material matrix [0095] d layer thickness of the coating layer [0096] h rib height [0097] M matrix material [0098] M1 first matrix material [0099] M2 second matrix material [0100] s thickness of the layer [0101] U peripheral direction [0102] x rib width [0103] y depression width