JP2009091793A - Sheet with window for reinforcing concrete in two directions and method of reinforcing concrete structure by the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet for reinforcing concrete enabling the user to progressively observe the state of the surface of a concrete structure after the reinforcement. <P>SOLUTION: This sheet comprises warps 6A and wefts 6E each having fiber bundles 6 formed by combining yarn bundles 6c of high performance fibers. The sheet has two-directional woven portions 5a woven in two vertical and lateral directions by using these warps and wefts. The adjacent two-directional woven portions 5a, 5a are connected through warp connection parts 5b formed of only the warps 6A and weft connection parts 5c formed of only the wefts 6B. An observation window 5d is formed through a body between the warp connection parts adjacent to each other in the lateral direction and the weft connection parts adjacent to each other in the vertical direction. A frame-like molten adhesive part 8 molten and adhered by a thermally adhesive yarn is formed along the periphery of each observation window. Each observation window is prevented from being displaced by preventing the warps from being loosened by a yarn displacement prevention yarn. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

    The present invention relates to a sheet for bidirectional concrete reinforcement with a window using high-performance fibers such as aramid fibers suitable for reinforcement of an existing concrete structure, and a method for reinforcing an existing concrete structure using the reinforcement sheet. . Here, the two-way concrete reinforcing sheet is a reinforcing sheet in which high-performance fibers are woven in two directions, ie, the vertical direction and the horizontal direction.

    Conventionally, for example, a method of reinforcing an existing concrete structure using a sheet woven using high-performance fibers such as aramid fibers for warp and weft yarns is known (Patent Document 1).

    In addition, in order to observe the surface state of the structure after reinforcement, a high-performance reinforcing sheet (hereinafter simply referred to as “one-directional sheet”) having a large tensile strength only in one direction is vertically and horizontally arranged. Using a rectangular space created between the vertical and horizontal sheets (hereinafter referred to as the “observation window” in this specification) There is also a proposal that makes it possible to visually check the state of cracks and the like after reinforcement construction, and also prevents the water penetrating from the road surface from staying between the concrete and the reinforcement sheet by using the observation window ( Patent Document 2).

JP 2000-199208 A JP 2005-029953 A

    However, in that case, in order to paste the unidirectional sheet vertically and horizontally, (1) after the unidirectional sheet is pasted and cured in the lateral direction, (2) from above the pasted unidirectional sheet, Two sheet sticking steps, such as affixing a unidirectional sheet in the direction and curing, are necessary, and there is a disadvantage that it takes time and labor for the work.

    In addition, in the part where the unidirectional sheet intersects vertically and horizontally, unevenness occurs according to the thickness of the sheet between the intersecting unidirectional sheets, and there is an inconvenience that further time and labor are required for the leveling process. .

    It is also possible to weave the reinforcing sheet in the form of an observation window, but high-performance fibers such as aramid fibers have a smooth surface, thin filaments, and poor rigidity. When weaving, the warp yarn or weft yarn is missing, and the high-performance fiber may cause yarn misalignment or yarn disturbance during construction at the site, and the observation window may be deformed or its installation position may change. Inconvenience is likely to occur.

    In view of the circumstances described above, the present invention observes the surface state of a structure after reinforcement, and prevents water penetrating from the road surface from staying between the concrete and the reinforcing sheet and discharging it to the outside. And it is not necessary to stick a plurality of unidirectional sheets vertically and horizontally in a grid pattern, and therefore, there is no need for uneven surface treatment at the intersections, and a two-way concrete reinforcing sheet with a window and An object of the present invention is to provide a method for reinforcing a concrete structure using the reinforcing sheet.

    Furthermore, another object of the present invention is to provide a window-equipped bi-directional concrete reinforcing sheet and a method for reinforcing a concrete structure using the reinforcing sheet, in which the observation window is not easily deformed and the installation position is difficult to shift. Is.

The invention according to claim 1 has a main body (10) formed in a sheet shape as a whole, and a reinforcing sheet (5) which is attached to a concrete structure surface (3) to reinforce the concrete structure (1). In
The body (10)
It consists of warp yarn (6A) and weft yarn (6B) which are a bundle of a plurality of yarn bundles (6c) made of a plurality of high-performance fibers, which are used as a fiber bundle (6). A plurality of two-way woven portions (5a) woven in a direction;
These two-way woven portions are arranged at predetermined intervals (L1, L2) in the vertical and horizontal directions,
The two-way woven portions (5a, 5a) adjacent in the longitudinal direction (arrow A direction) are connected by a warp yarn connecting portion (5b) consisting only of the warp yarn (6A),
Between the two-way woven portions (5a, 5a) adjacent in the lateral direction (arrow B direction), the weft connecting portion (5c) consisting only of the weft yarn (6B) is connected,
An observation window (5d) penetrates the main body between the two warp yarn connection portions (5b, 5b) adjacent in the horizontal direction and the two weft yarn connection portions (5c, 5c) adjacent in the vertical direction. Formed,
Each of the observation windows (5d) is composed of a plurality of yarns along the boundary portion of the warp yarn connecting portion (5b) adjacent to the observation window (5d), and constitutes the weft yarn (6B). Each yarn bundle (6) has a yarn misalignment prevention yarn (5e) for restraining each fiber bundle (6).
Around the observation window (5d), at least the warp yarn (6A) and the weft yarn (6B) adjacent to the observation window, and the fiber bundle (6) constituting the warp yarn and the weft yarn are heat-melted. A melt-bonded portion (8) in the form of a frame surrounding the periphery of each observation window is formed by melt-bonding by threading,
It is configured as a feature.

    The invention of claim 2 is characterized in that the entire reinforcing sheet is impregnated and solidified to facilitate handling of the subsequent reinforcing sheet.

According to a third aspect of the present invention, the observation window has a square shape having a size of about 50 to 150 mm in length and width, and the two-way woven portion has a breaking load in a state where the observation window is formed. The dimensions are set so that the reinforcing sheet 5 has a width of about 340 to 590 kN per meter.
It is configured as a feature.

The invention of claim 4 is an invention of a method for constructing an existing concrete structure. When the above-mentioned bidirectional concrete reinforcing sheet with a window is attached to an existing concrete structure to reinforce the concrete structure,
In the construction site, before applying the window-oriented bi-directional concrete reinforcing sheet to the concrete structure, an adhesive is applied over the entire surface of the reinforcing sheet, and the concrete structure to which the reinforcing sheet is to be applied is applied. Apply the adhesive to the surface of the object in advance,
In that state, the reinforcing sheet coated with the adhesive is placed on the surface of the existing concrete structure to which the adhesive has been applied in advance, and the adhesive is further coated on the surface of the reinforcing sheet. Configured.

    According to the first aspect of the present invention, not only can the reinforced concrete structure be observed over time and the water discharged outside through the observation window, but also two-way weaving from warp and weft yarns. Depending on the part, the concrete structure is reinforced in the vertical and horizontal directions with one reinforcing sheet, and it becomes unnecessary to apply the two reinforcing sheets twice in the vertical and horizontal directions. This eliminates the need for inland treatment at the intersection.

    The frame-shaped melt-bonded portion (8) and the yarn misalignment prevention yarn (5e) prevent the observation window from being deformed and its position from being displaced, which is effective in preventing deformation of the reinforcing sheet. , You can do the exact pasting work to the set place.

    According to the invention of claim 2, since the entire sheet is impregnated and solidified with the resin, the rigidity of the sheet is increased and the handling of the reinforcing sheet is facilitated.

    According to the invention of claim 3, the dimensions (L3, L4) of the two-way woven portion are such that the breaking load is about 340 to 590 kN per meter width of the reinforcing sheet in the state where the observation window is formed. Since it is set, the concrete structure can be properly reinforced regardless of the presence of the observation window.

    According to invention of Claim 4, before sticking a reinforcement sheet | seat on the surface of a structure, a certain amount of tackiness is previously given to a smooth reinforcement sheet | seat by apply | coating an adhesive agent to this reinforcement sheet | seat. Therefore, the reinforcement sheet can be smoothly applied to the surface of the structure in cooperation with the adhesive applied to the surface of the structure.

    Note that the numbers in parentheses are for the sake of convenience indicating the corresponding elements in the drawings, and therefore the present description is not limited to the descriptions on the drawings.

    Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing an example of a road floor board reinforced with high-performance fibers. FIG. 2 is an exploded perspective view showing a process for reinforcing the road floor board of FIG. 1 using high-performance fibers. FIG. 3 is an enlarged plan view showing details around the observation window for high-performance fibers, and FIG. 4 is a plan view showing an example of the entire concrete reinforcing sheet.

    As shown in FIG. 1, the road floor board 1 which is a concrete structure is formed in a plate shape having a thickness T as a whole. In the case of FIG. It is shown upside down from the installed state. That is, the surface facing the lower side of the road floor board 1 in the figure is the road surface 2 on which the vehicle or the like travels, and the surface facing the upper side in the figure is the lower surface 3 supported by the pier or the like.

    On the lower surface 3, a reinforcing sheet 5 made of high-performance fibers such as aramid fibers is attached to almost the entire surface of the floor plate lower surface 3 using an adhesive such as an epoxy resin. As shown in FIG. 3A, the reinforcing sheet 5 has a main body 10 formed as a thin sheet as a whole, and the main body 10 has a high performance made of a large number of aramid fibers. A yarn bundle 6c composed of a predetermined number of fiber yarns (for example, 3160 dtex aramid fibers), and a plurality of yarn bundles 6c are bundled into a fiber bundle 6 to form a basket weave as warp yarn 6A and weft yarn 6B. It has many two-way woven portions 5a. Further, as shown in FIG. 1, each bi-directional woven portion 5a has a predetermined interval L1, along the directions of arrows A and B (vertical and horizontal directions), which are the extending arrangement directions of the warp yarn 6A and the weft yarn 6B. They are arranged at L2.

    In the direction of the arrow A (longitudinal direction) in which the warp yarn 6A extends between the two-way woven portions 5a and 5a adjacent to each other, only the warp yarn 6A has the two-way woven portion 5a adjacent to the arrow A direction. The warp yarn connecting portions 5b are formed by the warp yarns 6A arranged. Further, in the arrow B direction (lateral direction) in which the weft yarn 6B extends between the two-way weaving portions 5a and 5a adjacent to each other, only the weft yarn 6B is adjacent to the arrow B direction. 5a and 5a are connected to each other, and a weft thread connecting portion 5c is formed by the disposed weft thread 6B.

    Due to the plurality of two-way woven portions 5a and the warp yarn connection portion 5b and the weft yarn connection portion 5c that connect them, the concrete reinforcing sheet 5 has two warp yarn connection portions 5b, 5b and longitudinally adjacent to each other in the lateral direction. An observation window 5d having a length L1 in the direction of arrow A and a length L2 in the direction of arrow B, which is surrounded by two weft connecting portions 5c and 5c adjacent to each other in the direction, is the reinforcing sheet 5. A large number are formed so as to penetrate the front and back of the main body 10.

    A vertical sheet connected to the two-way woven portion 5a and the two-way woven portion 5a of the left and right edge portions of each observation window 5d in FIG. 3 (a) of the reinforcing sheet 5 in FIG. 3 (a). Along the boundary of the yarn connecting portion 5b, yarn misalignment preventing yarns 5e (for example, polyester yarn of 280 dtex) composed of a plurality of yarns are arranged in the vertical direction, and each yarn misalignment preventing yarn 5e is As shown in FIG. 3B, a plurality of yarn bundles 6c constituting each weft yarn 6B are grouped together for each of the plurality of yarn bundles 6c, and thus for each fiber bundle 6, and the fiber bundle 6 is unwound. To prevent this, the fiber bundles 6 are sandwiched and bound in the vertical direction (the front and back direction of the reinforcing sheet 5) in the figure to restrain the movement. In addition, the reinforcing sheet 5 is connected to the two-way weaving portion 5a and the two-way weaving portion 5a of the upper and lower edge portions of each observation window 5d in the drawing in the horizontal direction in FIG. 3A. A yarn misalignment preventing yarn 5f (for example, 280 decitex polyester yarn) is disposed in the left-right direction along the portion 5c, and this yarn misalignment preventing yarn 5f is integrated with the weft yarn 6B adjacent to the observation window 5d. Are woven into the warp yarn 6A. Therefore, the yarn misalignment preventing yarn 5f together with the weft yarn 6B has a certain degree of misalignment preventing effect, although the fiber bundle 6 is not restrained as much as the yarn misalignment preventing yarn 5e on the warp yarn 6A side.

    Of the warp yarn 6A and the weft yarn 6B, at least the fiber bundles 6D and 6D constituting the warp yarn 6A and the weft yarn 6B arranged at positions adjacent to the observation window 5d (fiber bundles in a portion adjacent to the observation window 5d) 6 is particularly referred to as a fiber bundle 6D. The same applies to each of the yarn bundles 6c. Each yarn bundle 6c is made of nylon yarn, polyester yarn or the like of 40 to 250 dtex, preferably 50 to 125 dtex, and is easily melted by heating. A heat-sealing yarn (not shown) having a melting point is arranged in a form of being melt-bonded by a heater (tube heater or the like) during weaving. As a result, the fiber bundles 6D and 6D are formed so as to surround each observation window 5d in a melt-bonded form with the yarn bundles 6c constituting the fiber bundles 6D and 6D, as shown in FIG. As shown, a frame-shaped melt-bonded portion 8 is formed. That is, among the warp yarn 6A and the weft yarn 6B, the warp yarn 6A and the weft yarn 6B arranged at least at a position adjacent to the observation window 5d are heat-sealed yarns arranged in the warp yarn 6A and the weft yarn 6B. Is melted to form an adhesive as if it were a flat strip. A heat-sealing yarn is used for the weft yarn 6B, but at least a portion of the warp yarn 6A and the weft yarn 6B adjacent to the observation window 5d is melt-bonded with the heat-sealing yarn to constitute the melt-bonding portion 8. I can do it.

    The arrangement of the heat-spun yarn bundles 6c is arbitrary, and the heat-sealable yarn is melted by the heat treatment during weaving of the reinforcing sheet 5, so that the yarn bundles 6c are bonded to each other. As long as the melt-bonded portion 8 can be formed, any mode may be used. Each yarn bundle 6c is arranged on the outer peripheral portion so as to cover the heat-sealed yarn, and is melted simultaneously at the time of manufacturing to form a frame-shaped melt-bonded portion 8. During this heating, the above-described yarn misalignment prevention yarn 5e sandwiches the fiber bundle 6 of the weft yarn 6B and effectively prevents the fiber bundle 6 of the adjacent warp yarn 6A from being unwound. Further, the four corners P1, P2, P3, and P4 of the square observation window 5d formed in such a manner that the fiber bundles 6 intersect with each other are vertical around the observation window 5d by a tube heater provided in the loom when the reinforcing sheet 5 is woven. Since the heat-bonding yarns arranged in the yarn 6A and the weft yarn 6B are heated and melted to form the melt-bonding portion 8, the position of the observation window 5d can be correctly held.

    Thus, the reinforcing sheet 5 forms a frame-shaped melt-bonded portion 8 as shown in FIG. 3C, and the positions of the four corners P1, P2, P3, P4 around each observation window 5d are The warp yarn 6A is reliably fixed by the formed frame-shaped melt-bonding portion 8, and the warp yarn 6A is prevented from being unwound by the yarn misalignment prevention yarn, and an observation window 5d having a predetermined shape and position is formed on the reinforcing sheet 5. The Note that the warp yarn 6A and the weft yarn 6B on which the heat-sealing yarn is arranged may include at least the warp yarn 6A and the weft yarn 6B at positions adjacent to the periphery of the observation window 5d.

    For example, as shown in FIG. 4, the reinforcing sheet 5 has four observation windows 5d at intervals L4 in the horizontal direction (width direction) and at intervals L3 in the vertical direction (length direction). The observation window 5d is formed in a matrix shape, and the size of each observation window 5d is, for example, 50 mm or 100 mm. The intervals C, L3 and L4 and the vertical and horizontal sizes L1 and L2 of the observation window 5d are arbitrary, but when it is desired to increase the reinforcing effect by giving priority to the amount of high-performance fibers constituting the reinforcing sheet 5. It is preferable that the size of each observation window 5d is reduced and the distances L3 and L4 are taken as much as possible to make the size of the two-way woven portion 5a as large as possible. Further, the width D of the reinforcing sheet 5 (set to 1100 mm in FIG. 4) and the length in the upper and lower direction in FIG. 4 (set to a long object in FIG. 4) are arbitrary, but the observation window Considering the weaving property and ease of handling of the reinforcing sheet 5, the size of 5d is practically desirably a square having a size of about 50 to 150 mm in length and width (it is not necessarily a square, but the reinforcing effect is reinforced). The observation window 5d is preferably a square in order to be evenly exhibited in the width and length directions of the sheet 10, and in order to obtain a predetermined reinforcing effect, the two directions sandwiched between the observation windows 5d The dimensions L3 (length direction) and L4 (width direction) of the woven portion 5a are such that the breaking load is about 340 to 590 kN per meter of the width D of the reinforcing sheet 5 with the observation window 5d formed. It is desirable to set the dimensions There.

    Since the road floor board 1 and the reinforcing sheet 5 have the above-described configuration, when the lower surface 3 of the road floor board 1 which is an existing concrete structure is reinforced with the reinforcing sheet 5, first, as shown in FIG. Thus, the curing tape 7 is affixed to each observation window 5d of the reinforcing sheet 5 at the portion where the reinforcing sheet 5 of the lower surface 3 of the road floor board 1 to be reinforced is applied, and a primer is applied to the lower surface 3 of the road floor board 1 Apply.

    For the reinforcing sheet 5, the reinforcing sheet 5 is placed on a work table in advance, and an adhesive such as an epoxy resin is applied over the entire surface of the reinforcing sheet 5 in that state. At this time, since the reinforcing sheet 5 is provided with the observation window 5d at the already designed position, the distortion is adjusted and the adhesive is applied and impregnated so as not to be deformed.

    Next, after the lower surface 3 of the road floor board 1 to be reinforced, which is the surface of the existing concrete structure, is treated with a primer, an adhesive such as an epoxy resin is applied undercoat, and in that state, the adhesive is coated and impregnated. As shown in FIG. 2, the sheet 5 is attached to the lower surface 3 so that each observation window 5 d of the reinforcing sheet 5 is aligned with the curing tape 7 attached to the lower surface 3 of the road floor board 1. In this state, an adhesive such as an epoxy resin is further applied on the reinforcing sheet 5 so as to be overcoated, and the reinforcing sheet 5 is attached to the lower surface 3 of the road floor board 1 as shown in FIG. Thereafter, the curing tape 7 located in each observation window 5d of the reinforcing sheet 5 is removed so that the lower surface 3 of the road floor board 1 is directly exposed to the observation window 5d portion. Since the adhesive is applied to the reinforcing sheet 5 in advance, and the adhesive is also precoated on the lower surface 3 of the road floor board 1, the pasting work between the reinforcing sheet 5 and the lower surface 3 of the road floor board 1 is performed. The adhesive applied to the reinforcing sheet 5 and the floor plate lower surface 3 can be performed in a short time and reliably.

    In this state, when the adhesive is cured and solidified, the reinforcing sheet 5 is affixed to the lower surface 3 of the road floor board 1 and the road floor board 1 is reinforced by the reinforcing sheet 5. Since the warp yarn 6A and the weft yarn 6B are arranged in the directions of the arrows A and B orthogonal to each other (that is, the vertical and horizontal directions), the lower surface 3 of the road floor board 1 is in the directions of the arrows A and B orthogonal to each other. It is appropriately reinforced in all directions of the lower surface 3. In addition, since the vertical and horizontal directions of the lower surface 3 of the road floor board 1 are reinforced at a time by the pasting operation of the reinforcing sheet 5 once, the high-performance fibers are used twice in the vertical and horizontal directions as in the past. The pasting work is no longer necessary, and quick construction is possible.

    Further, since the reinforcing sheet 5 is appropriately reinforced in two directions, the sheets do not intersect with each other, and when the unidirectional sheets are pasted in a lattice shape in the vertical and horizontal directions, between the intersecting sheets This is convenient because it eliminates the hassle of inland processing. And the state of the crack after reinforcement of the lower surface 3 of the road floor board 1 can be observed anytime through the observation window 5d.

    In addition to the aramid fibers, the high-performance fibers constituting the reinforcing sheet 5 are high-strength fibers having high tensile strength such as carbon fibers, glass fibers, polyarylate fibers, and PBO fibers. It can be used in combination with more than one species. Furthermore, the reinforcing sheet 5 is impregnated and solidified with an epoxy resin in advance, and if it is produced as a molded product, for example, at a factory (not necessarily a factory), the rigidity is increased, handling is facilitated, and workability is improved. I can do it.

FIG. 1 is a perspective view showing an example of a road floor board reinforced with high-performance fibers. FIG. 2 is an exploded perspective view showing a process for reinforcing the road floor board of FIG. 1 using high-performance fibers. FIG. 3 is an enlarged plan view showing details around the observation window for high-performance fibers. FIG. 4 is a plan view showing an example of the entire concrete reinforcing sheet.

Explanation of symbols

1 …… Concrete structure 3 …… Surface (lower surface)
5 ... Reinforcing sheet 5a ... Two-way woven portion 5b ... Warp yarn connecting portion 5c ... Weft yarn connecting portion 5d ... Observation window 5e ... Yarn misalignment preventing yarn 6 ... Fiber bundle 6A ... Warp yarn 6B ...... Weft 8 ... Melt bonding part 10 ... Body

Claims (4)

In a concrete reinforcing sheet that has a main body formed entirely in the form of a sheet and is affixed to the surface of a concrete structure to reinforce the concrete structure,
The body is
Composed of warp yarns and weft yarns that bundle multiple yarn bundles made of multiple high-performance fibers into a fiber bundle, and using these warp yarns and weft yarns, there are multiple two-way weaving parts that are woven in two vertical and horizontal directions And
These two-way woven portions are arranged at predetermined intervals in the vertical and horizontal directions,
The two-direction woven portions adjacent to each other in the longitudinal direction are connected by a warp yarn connecting portion made of only the warp yarn,
Between the two-direction weaving portions adjacent to each other in the lateral direction, they are connected by a weft connecting portion made of only the weft yarn,
An observation window is formed in a form penetrating the main body between the two warp yarn connecting portions adjacent in the horizontal direction and the two weft yarn connecting portions adjacent in the vertical direction,
Each fiber bundle is composed of a plurality of yarns along the boundary portion of the warp yarn connecting portion adjacent to the observation window of each observation window, and each fiber bundle constituting the weft yarn is restrained for each fiber bundle. Has thread prevention thread,
Around each observation window, at least the warp yarn and the weft yarn adjacent to the observation window, and the fiber bundles constituting the warp yarn and the weft yarn are melt-bonded by heat-sealing yarn, and each observation window is formed. A frame-shaped melt-bonded part surrounding the periphery of
A sheet for reinforcing bi-directional concrete with a window. 2. The two-way concrete reinforcing sheet with a window according to claim 1, wherein the entire reinforcing sheet is impregnated and solidified to facilitate handling of the reinforcing sheet thereafter. The observation window has a square shape having a size of about 50 to 150 mm in length and width, and the two-way woven portion has the observation window formed, and the breaking load is 1 meter in width of the reinforcing sheet. The dimensions are set to be about 340 to 590 kN per hit,
The sheet for bidirectional concrete reinforcement with a window according to claim 1. When a sheet for reinforcing bi-directional concrete with a window according to claim 1 is applied to an existing concrete structure to reinforce the concrete structure,
In the construction site, before applying the window-oriented bi-directional concrete reinforcing sheet to the concrete structure, an adhesive is applied over the entire surface of the reinforcing sheet, and the concrete structure to which the reinforcing sheet is to be applied is applied. Apply adhesive to the surface of the object,
In that state, the reinforcing sheet coated with the adhesive is placed on the surface of the existing concrete structure to which the adhesive has been applied in advance, and the adhesive is further coated on the surface of the reinforcing sheet. Configured
Reinforcement method for existing concrete structures.

Images