ES2198538T3 - PROCEDURE FOR REINFORCEMENT OF A CONSTRUCTION WORK, AND REINFORCED WORK. - Google Patents

Abstract

A FIRST REINFORCEMENT (32) IS APPLIED ON A FIRST SURFACE (33) OF THE WORK, AND A SECOND REINFORCEMENT (32A) ON A SECOND SURFACE (33A) OF THE WORK. THESE FIRST AND SECOND SURFACES ARE SITUATED IN THE PROLONGATION ONE OF ANOTHER, BUT SEPARATED BY AN OBSTACLE (31) THAT IMPROVES TO APPLY CONTINUOUSLY A UNIQUE REINFORCEMENT. BEFORE APPLYING THE REINFORCEMENTS, A HOLE (34) IS ATTACHED AT LEAST (31) LOCATED BETWEEN THE FIRST AND SECOND SURFACES; THIS HOLE IS FILLED WITH RESIN AND A FIBER DATE (35), LEAVING EXTREME PORTIONS (36) OVERDAY OUTSIDE THE SIDE OF THE SURFACES FIRST AND SECOND RESPECTIVELY. EACH ONE OF THE REINFORCEMENTS IS PAID BELOW ABOVE A PORTION OF EXTREME RESPECTIVE OF THE FIBER DATE. Thus, despite the obstacles (31), a continuity of response of the efforts through the reinforcements applied.

Description

Reinforcement procedure for a work of construction, and work thus reinforced.

The present invention relates to the field of Structurally reinforced construction sites.

In this field, it is usual to paste some reinforcements by means of appropriate resins on the parts of a work a beef up.

In a classic procedure currently applied, called the Lhermite procedure, the reinforcement consists of a steel plate glued on concrete after preparation of The glue surface. This classic procedure has followed various developments taking into account in particular the evolution technology of materials, and more particularly the evolution of sheet metal replacement materials, which raises frequently use problems and need provisions To fight corrosion.

This is how the latter have been seen years a material-based reinforcement techniques compounds in the form of glued plates (see for example FR-A-2 594 871), and then fit of bonded fibers (see US-A-5 308 430) and glued fabrics. These last types of reinforcement present numerous advantages, in particular its application comfort and its ability to apply on surfaces of various shapes.

These different types of reinforcement stuck very significantly improve the dynamic behavior of the work reinforced On the other hand it is very rare to observe a break in the reinforcement itself. Figure 1 shows a schematic section of a 8 reinforced concrete beam resting on two props 9 nearby at its ends, and whose lower face it presents, between these two braces 9, a glued reinforcement 10 that resists tensile according to the longitudinal direction of the beam. The glued reinforcement 10 improves the behavior of beam 8 in response to an effort F that tends to make it flex between its two supports 9. When the effort F is important enough to cause a break in the beam structure, this break usually occurs in the concrete `` coating '', that is in the concrete thickness not armed between the surface provided with the glued reinforcement 10 and the underlying armor irons 11. Typically, the break 12 starts in the vicinity of one of the ends of the reinforcement glued 10 under the effect of shear stress E resulting from the reaction R of one of the supports 9 and the tensile stress T which exerts the reinforcement 10, and then propagates along the armor irons 11. In other words, it is the concrete of the work he who gives in, in a part where he doesn't work under compression (his mode  of desired solicitation) but to shear.

Moreover, even if some reinforcements, in particularly those based on carbon fiber fabrics, they can be applied on a variety of supports, they can remain obstacles that bother the continuous application of said reinforcements, thus allowing weakening in the reinforced work. In the case of a building, you can have these discontinuities at the level of the passage from one piece to another through a wall, or from one floor to another through a floor. Also, if the surface to be reinforced has transverse ribs at a direction in which the reinforcement must ensure resistance to traction, these ribs are not usually covered by the reinforcement since a draping of the reinforcement above said rib would make you lose the essential part of your properties of tensile strength.

The document US-A-5 218 810 describes a reinforcement compound that does not adhere directly to the support against which It is applied. This support is a concrete element in the form of column, to which the composite reinforcement surrounds to form a coherent protection shell. In WO95 / 34724, it has been proposed to extend these reinforcements to some application walls adherents Being the coquilla effect impossible topologically, the behavior of the reinforcement on the wall is assured by anchors installed with the help of drilled holes in the wall, these anchors can be covered by the reinforcement.

The present invention aims to improve the reinforcements of works by means of cast reinforcements eliminating a large part of the areas of weakness that may remain.

The invention thus proposes a method of reinforced a construction site, as stated in claim 1

The installed wick makes a kind of reinforcement between the surface provided with the cast reinforcement and the other reinforced zone. The placement of these armor wicks is easy from the moment the surface is accessible to paste in the same reinforcement.

The fiber wick has the advantage that it is easily folded and / or extended on the surface before cover it by the cast reinforcement. This ensures a good transmission of efforts while avoiding forming important highlights on the reinforced surface.

You can thus ensure unions between different portions of the same work covered with reinforcements respective glued

The fibers of the wick are preferably of carbon. However, it is possible to use glass fibers or synthetic fibers, even metallic fibers (rope of piano).

The glued reinforcement can in particular be based of sheet metal or composite material.

Preferably, this reinforcement consists of a band or a carbon fiber fabric that sticks on the surface covering the surface of a resin in a fluid state suitable for polymerization at room temperature, and then applying the band or the fabric on the coated surface so that the resin impregnate the fibers and ensure the bonding. The hole that receive the wick can then be filled with the same resin that that with which the surface is coated. These provisions Simplify the procedure to the fullest.

A second aspect of the invention relates to a construction site as set forth in the claim 5.

Other particular advantages of this invention will appear in the following description of an example of non-limiting realization, with reference to the attached plans, in which:

- Figure 1, discussed above, is a schematic view of a reinforced concrete beam provided with a glued and broken reinforcement under the effect of an effort of flexion;

- Figure 2 is a sectional view and in elevation, according to the plane II-II indicated in the figure 3, of a portion of reinforced concrete work equipped with a glued reinforcement;

- Figure 3 is a view below the work portion of figure 2;

- Figure 4 is a schematic view that illustrates the placement of a fiber wick according to the invention;

- Figure 5 is a sectional view, according to the V-V plane indicated in figure 6, of a floor reinforced rib in accordance with the present invention; Y

- Figure 6 is a view below, in section according to plane VI-VI indicated in figure 5, of reinforced ribbed soil.

Figures 2 and 3 illustrate an example of application of a reinforcement attached to a concrete floor slab 15 armed resting on support elements 16, which they can be walls, posts or the like. Between these support elements 16, of which only one is represented in figure 2, it is provided to provide the lower surface 17 of the slab 15 of a glued reinforcement 18.

The reinforcement 18 is intended to resist the traction according to a main direction A that goes from an element of 16 hold to another. The reinforcement 18 preferably consists of a band of scalloped carbon fibers oriented parallel to the A direction, or also in a carbon fiber fabric whose warp threads are oriented according to direction A, the carbon fibers impregnated with a resin that hardens room temperature. The placement of the reinforcement 18 can in Particularly be carried out as follows: an epoxy resin, suitable for polymerization at room temperature, it is coated in liquid state on the surface 17; the tissue band is a then applied on the coated surface so that the resin impregnate the fibers and ensure the bonding. The band or the fabric  It can be applied by simple gluing, which does not need the application of prolonged pressure.

The resin used is for example the resin bi-component epoxy consisting of a part by `` CECA XEP 3935 / A '' brand base resin, and on the other hand by the hardener brand `` CECA XEP 2919 / B '', these two being components manufactured and marketed by the company CECA S.A., 12 place de l'Iris, La Défense 2, Cedex 54, 92062 PARIS LA DEFENSE (FRANCE).

This resin presents, when its application in a fluid state, a viscosity at room temperature between 1,000 and 10,000 mPa.s.

This resin, once hardened, has:

- a shear strength compatible with that of the material that constitutes the work,

- a tensile strength between 5 and 100 MPa, with a long break between 0.5 and 10%,

- and a resistance to compression rupture between 5 and 100 MPa, with a shortening to rupture between 0.5 and 10%.

The ensimated carbon fibers that constitute the band or the fabric 18 has a resistance to rupture at traction that is greater than 1,500 MPa, and an elastic module between 200 and 400 GPa.

To ensure a reinforced concrete of coating 19 located between surface 17 and zone 20 of the volume of slab 15 comprising armor irons 21, fiber wicks 23, 24 are encased in about holes 25, 26 drilled between surface 17 and zone 20. The figures of each wick 23, 24 are impregnated with a resin 27 which fills the hole 25, 26.

The wicks 23, 24 preferably consist of ensimated carbon fibers that can be of the same nature than those of the fabric 18. The resin 27 with which the holes are filled can also be the same type as the one used for impregnation and for bonding the fabric 18.

Figure 4 illustrates the placement of said wick of fibers. In a first stage, the drilling of the hole 26. Resin 27 is then applied in a fluid state filling holes 26 and covering surface 17. It is lined then the wick 24 in a hole 26, leaving protruding an extreme portion 28 of this wick off the surface 17. It can provide a tail point at the end of the fibers of the wick 24 to facilitate the introduction of this wick in your orifice. The fibers of the wick 24 are then separated in the portion 28 protruding from surface 17, and then recessed these fibers on the surface 17 in the resin film, extending them along the surface. The transmission of efforts between the reinforced zone 20 and the bonded reinforcement 18 is the better when the fibers of the ends 28 are fan extended on either side of the main address A as shown by the Figure 3. The reinforcement fabric 18 is then applied, glue and let the resin harden.

The dimensioning of the holes and the wicks of fibers, and its distribution on the reinforced surface 17 will be in general defined on the basis of structure calculations conducted by the study office.

It is generally wise to drill a hole relatively deep 23 in a region of surface 17 that will be covered by the reinforcement 18 and adjacent to an edge 29 of This reinforcement. This hole 23 is perforated in one direction. oblique with respect to surface 17. From surface 17 towards the bottom of hole 23, this hole moves away from the center of the reinforcement 18 as shown in Figure 2. The direction of hole drilling 25 and the main direction A are in the plane of figure 2 which is perpendicular to the surface 17. The drilling angle of this hole 25 can be chosen from so that the hole 25 is substantially perpendicular to the shear force exerted at the level of the edge 29 of the reinforcement glued (see figure 1). The wick 23 thus performs a kind of continuity of tensile stress between glued reinforcement 18 and reinforcing iron 21 of concrete.

Other means of union are planned between iron reinforcement irons and glued reinforcement 18, spread over the extension of the glued reinforcement 18. These means of union could simply consist of nails or the like. But they are preferably also made up of wicks of fibers 24 embedded in resin 27 and inserted into holes 26 drilled transversely to surface 17 as has illustrated in figures 2 to 4. In these figures, holes 26 they are represented perpendicular to surface 17, but they will understand that they could also be inclined in it sense that the holes 25 provided at the ends.

It is possible to exert on the fabric 18 a prestressed by tensioning according to direction A. The tension It is applied to one or both ends of the fabric and held until Full hardening of the bonding resin. After relaxation of the prestressing, the glued reinforcement exerts on the structure active efforts against charges Applicants

Figures 5 and 6 illustrate an application of according to the invention, of a glued reinforcement 32, which can be of the same type as above, on an irregular support that it consists, in the example considered, on the underside of a ribbed soil 30, whose ribs 31 are transverse to the main direction A according to which the reinforcement must resist tensile stresses

There is thus not one but several reinforcements 32, 32a, 32b ... stuck on successive floor surfaces 30 located in extension of each other, but separated from each other the others by the ribs 31 that prevent the continuous application of the single reinforcement.

The invention allows in this case to ensure a transmission of tensile stresses between two reinforcements next separated by a rib 31.

Each hole 34 intended to receive a wick of fibers 35 is then perforated through rib 31, of so that it fits with the two surfaces 33, 33a located in prolongation of each other. The fiber wick 35 is introduced in this hole 34 leaving its two ends 36 protruding one and other side of the rib 31. At the level of these two ends 36, the  fibers of the wick 34 are separated and extended to each other side of address A as shown in figure 6, to ensure the Better transmission of efforts.

Claims (8)

1. Reinforcement procedure of a construction site (30), in which a first reinforcement (32) is glued on a first surface (33) of the work, and a second reinforcement (32a) on a second surface (33a) of the work, said first and second surfaces being located in extension of one another, but separated by an obstacle (31) that prevents the continuous application of a single reinforcement, characterized in that at least one of the reinforcements is glued hole (34) through the obstacle (31) between said first and second surfaces; and said hole is filled with resin (27) and with a wick of fibers (35) of which two end portions (36) are respectively allowed to protrude from the side of said first and second surfaces, each of the reinforcements then being glued above a respective end portion of the fiber wick. 2. Method according to claim 1, characterized in that the fibers of the wick (35) are separated in each of its end portions (36), and these fibers are spread over each of the first and second surfaces (33, 33a) before covering it by its glued reinforcement (32, 32a). 3. Method according to claim 2, in the that each reinforcement (32, 32a) is arranged to resist the traction according to a main direction (A) of said surfaces (33, 33a), and in which the fibers of each end portion (36) of the wick (35) are fan-extended on either side of said  Main address. 4. Procedure according to any of the claims 1 to 3, wherein the reinforcements (32, 32a) consist of bands or fabrics of carbon fibers that are glue coating the surfaces (33, 33a) of a resin in state fluid suitable for polymerization at room temperature, and then applying the bands or fabrics on the coated surfaces so that the resin permeates the fibers and ensures the bonding, and in the which the hole (34) is filled with the same resin (27) as that with which the surfaces are coated. 5. Construction work, which has at least some first and second surfaces (33, 33a) respectively provided with glued reinforcements (32, 32a), said first and second surfaces being located in extension of one another, but separated by a obstacle (31) that prevents the continuous application of a single reinforcement, characterized in that at least one wick of fibers (35) extends between said first and second surfaces in a hole (34) filled with resin (27), passing through the hole (34) the obstacle between said first and second surfaces, and the fiber wick having two end portions (36) protruding respectively on said first and second surfaces and above which said reinforcements (32, 32a) are glued. 6. Construction site according to claim 5, in which the wick fibers (35), in their extreme portions (36), are extended on said surfaces (33, 33a). 7. Construction site according to claim 6, in which the reinforcements (32, 32a) are arranged to resist tensile according to the main direction (A) of said surfaces (33, 33a), and in which the extreme portions (36) of the wick is fan-extended on either side of said Main address. 8. Construction site according to any of the claims 5 to 7, wherein each of said reinforcements (32, 32a) consists of a band or fabric of carbon fibers impregnated with a resin (27) that ensures the bonding of the fabric on the surface (33, 33a) of the work and that is the same composition that the resin with which the hole (34) is full.