JP6637634B1 - Mortar bonding aid for connector - Google Patents

Abstract

An object of the present invention is to provide a connector and mortar bonding aid which does not cause defects such as cracks in mortar applied to an outer wall surface of a concrete structure or an outer wall tile on the mortar. A circular body (1), a bolt catcher (2) that can be inserted through the circular body (1), has a screw portion on the inside, and is screwed with a spacer bolt set in a concrete formwork; A plurality of loop portions 5 which are provided with a fittable circular lid 3 and form clamping bolts 4 and which engage with mortar are arranged in parallel or radially on the end face of the circular lid 3 on the skeleton concrete surface side. Then, a projection is provided on the inner surface side of the circular lid 3, the bolt catcher 2 is inserted into the circular main body 1, and the circular main body 1 and the circular lid 3 are fitted to each other. When the screw is engaged, there is a slight gap between the protrusion and the end face of the bolt catcher 2, or the protrusion and the end face of the bolt catcher 2 abut. [Selection diagram] Fig. 1

Description

  The present invention provides a connector mortar that functions as a connector for connecting a spacer bolt in a concrete form with a form tightening bolt, and also functions as an adhesion aid when applying mortar to the surface of a hardened concrete body. It relates to a bonding aid.

  The concrete structure is held at a constant interval by interposing a plurality of spacer bolts between the front and rear two formwork, and concrete is poured between the formwork at the constant interval, and after the concrete hardens, the formwork is formed. Is to be built by removing it. In addition, the surface of the skeleton concrete after removing the formwork is coated with a base mortar to remove irregularities and secure an even thickness. Further, a mortar is applied, and a finishing material such as a tile is applied to complete the mortar. A common method is to apply mortar to a certain thickness. However, tiles applied later with mortar may fall off the surface of the slab concrete due to aging. For this reason, various measures have conventionally been proposed to prevent such tiles and mortar from coming off.

  As a measure for preventing the above-mentioned tiles from being peeled off, the applicant of the present invention disclosed in Japanese Patent Application Laid-Open No. H11-157572 a trace of removal of a connector connecting between a spacer bolt in a concrete formwork and a bolt for fastening a formwork (so-called cone mark). By using this method, the present inventors have proposed an invention in which an excellent mortar peeling-preventing effect can be obtained by embedding a mortar bonding aid designed in a special structure into the cone mark. The present invention will be described with reference to FIGS.

  FIG. 9 shows a process of forming a cone mark on the surface of a skeleton concrete formed by a concrete formwork. FIG. 9 (A) shows a state where a concrete formwork is assembled, 20 is a frame concrete, 21 is a spacer bolt, 24 is a formwork, 25 is a connector, 26 is a formwork fastening bolt, and the formwork is shown. The tightening bolt 26 is integrally connected to the connector 25.

  The spacer bolt 21 is inserted perpendicular to the mold so as to form a space for placing concrete between the front and rear two pieces of the mold 24 and a mold (not shown). 25 is screwed. The formwork 24 is penetrated by a formwork tightening bolt 26 extending from the connector 25, the inner surface of the formwork 24 is brought into contact with the outer end surface of the connector 25, and the formwork tightening bolt 26 is sandwiched outside thereof. A pair of side end thick members 27, 27 are arranged, further held down by a foam tie 28, and a nut 29 is screwed into a form tightening bolt 26 and tightened to complete the assembly.

  Concrete 20 is poured into the space for placing concrete between the molds, and when it hardens, it is released. The nut 29, the foam tie 28, the side end thick member 27, and the formwork 24 are removed by a series of demolding operations, and when the connector 25 is finally removed, the removal trace of the connector 25 is shown in FIG. 9B. Such a cone mark 22 is formed. Here, the connector 25 that has been deformed or damaged is usually discarded as waste material.

  The invention of Patent Document 1 is represented by a mortar bonding aid 30 as shown in FIG. 10, in which an embedding part 31 and a number of loop-shaped locking parts 32 are integrally formed from resin. I have. An insertion hole 33 into which the end of the spacer bolt 21 is fitted is formed at the bottom of the plug portion 31.

  As shown in FIG. 10 (A), after applying the adhesive 34 around the plug 31, the mortar bonding aid 30 is applied to the inside of the cone trace 22 formed on the surface of the skeleton concrete 20 as described above. And only the locking portion 32 is exposed on the surface as shown in FIG. Then, as shown in FIG. 10 (C), mortar 23 is applied to a predetermined thickness so as to cover both surfaces of mortar bonding aid 30 and concrete 20 from above.

  However, in the mortar bonding aid 30, the locking portion 32 having high rigidity is obtained by integrally molding the locking portion 32 with the plug portion 31 from the viewpoint of the mortar peeling preventing action. Since it can penetrate deeply into the hardened mortar, it exhibits a high anchoring effect after hardening, and an excellent effect is obtained in preventing the mortar from peeling off.

  However, when examining the overall pretreatment work for preventing the mortar from peeling off, in the above series of work, the connector after being removed from the spacer bolt is discarded as waste after one to several uses, and this is industrial waste. There is a problem of taking things out. In addition, there is still a problem in that the workability is further improved by shortening the pretreatment for preventing the spallation.

  Therefore, Patent Document 2 discloses a connector which can solve the problem of industrial waste of a connector which becomes a waste material after being used once or several times, and can further shorten the work time of the pre-treatment for preventing tile peeling. A mortar bonding aid is disclosed. The connector / mortar bonding aid disclosed in Patent Document 2 is a bonding aid for mortar applied to the surface of skeleton concrete, and the mortar bonding aid is connected to a spacer bolt set in a concrete formwork. On the end surface on the concrete surface side, a large number of locking portions engaging with the mortar are arranged in parallel or radially and are integrally molded with the connector portion with resin, and the end portion of the connector portion is A support projection formed in a frame shape for accommodating the plurality of locking portions inside is provided along an outer peripheral edge.

  However, in the connector / mortar bonding aid disclosed in Patent Document 2, cracks may be seen in the mortar or the outer wall tiles on the mortar over time.

JP 2000-45480 A Japanese Patent No. 3976427

  The present invention has been made in view of such problems of the related art, and an object of the present invention is to provide a mortar applied to an outer wall surface of a concrete structure or an outer wall tile on the mortar, such as a crack. An object of the present invention is to provide a connector / mortar bonding aid that does not cause defects.

  Therefore, the present inventors, when performing tile peeling prevention by the roof bond-tough binder method (LT method), a defect such as a crack in the mortar applied to the outer wall surface of the concrete structure or the outer wall tile on the mortar. The cause of the occurrence was investigated. As a result, it was found that cracks were likely to occur in the tiles in places exposed to direct sunlight during the day, such as the southern, southwestern, and western outer walls, and were concentrated at the edge of the wall. Furthermore, it was found that there were many troubles of tiles in the thin part of the concrete frame itself of 20 cm or less in the outer part of the veranda, the tower house on the rooftop, the machine room such as the elevator, the eaves, the parapet etc. .

  Further, it is difficult to apply the tile-attached mortar with a uniform thickness, and it is recommended that the thickness of the attached mortar be 2 mm or more even in the above-mentioned LT method, but it is said that it is difficult to reliably implement the mortar. However, if the mortar is not sufficiently thick, the stress generated on the concrete skeleton side is not buffered by the mortar layer, and a load may be directly applied to the tile.

  In general, in RC structures, since the thermal expansion coefficients of reinforcing steel and concrete are close to each other, it is basically considered that a bimetal effect and a thermal stress difference due to a temperature difference hardly occur. However, in the above-described end portions and thin-walled portions, external forces other than heat are easily generated, and shear stress occurs in the in-plane direction at the boundary surface between the tile and mortar, and tensile stress occurs in the tile in the out-of-plane direction. Conceivable. Even if such a stress occurs, the restraining force is large at the center of the structure and it does not easily deform, but if the edges and the concrete frame itself are thin, it is highly likely that the deformation will occur due to the stress. .

  Now, let us consider a case where a tile crack occurs due to thermal expansion of a spacer bolt in a concrete formwork. That is, since the connector and mortar bonding aid is combined with the spacer bolt in the concrete formwork and also functions as a mortar bonding aid applied to the outer wall surface of the concrete structure, the spacer in the concrete formwork is used. When the bolt thermally expands and expands due to an external temperature in summer or the like, an out-of-plane tensile stress or a compressive stress is generated in the mortar or the outer wall tile on the mortar, which causes a crack in the tile. In this case, even if the spacer bolt in the concrete form expands due to thermal expansion, a crack is not generated in the tile if a structure in which the influence of the expansion of the spacer bolt is not transmitted to the mortar or the outer wall tile on the mortar is adopted. .

  That is, the connector and mortar bonding aid of the present invention is a mortar bonding aid that is applied to the surface of skeleton concrete and has a circular main body and a screw portion that can be inserted into the circular main body and is inside. A bolt catcher that is screwed into a spacer bolt set in a concrete formwork, a circular lid body that can be fitted to the circular body, and a form clamping bolt. A large number of loops engaging with the mortar are arranged in parallel or radially on the end surface on the concrete surface side, a protrusion is provided on the inner surface side of the circular lid, and a bolt catcher is inserted through the circular body to form a circular shape. When the spacer bolt is screwed into the bolt catcher when the main body is fitted with the circular lid, is there a slight gap between the protrusion and the end face of the bolt catcher? It is characterized in that the end face of the projection and bolt catcher abuts.

  On the end face of the circular lid on the side of the concrete surface of the skeleton, apart from a number of loops engaging with the mortar, a ridge is provided which can prevent mortar from entering the bolt catcher screw part. Is preferred.

  It is preferable that a plurality of projections are provided on the inner surface side of the circular lid.

  Since the connector and mortar bonding aid of the present invention is connected to the spacer bolts in the concrete form, the spacer bolts in the concrete form thermally expand due to the outside temperature in summer or the like, and are bolted together with the spacer bolts. The catcher may stretch. However, since there is a slight gap between the projection provided on the inner surface side of the circular lid and the end face of the bolt catcher, this gap absorbs the extension of the bolt catcher. Even if the bolt catcher extends beyond the length of the gap, the protrusion provided on the inner surface side of the circular lid serves as a cushioning material to receive the bolt catcher, and the mortar or the outer wall tile on the mortar is received from the spacer bolt. The transmission of stress to the device is interrupted. Further, when a bolt catcher is inserted into the circular body to fit the circular body and the circular lid, and when the spacer bolt is screwed with the bolt catcher, a projection provided on the inner surface side of the circular lid. Even if there is no slight gap between the end face of the bolt catcher and the projection provided on the inner surface side of the circular lid and the end face of the bolt catcher abut, the projection also provided on the inner surface side of the circular lid body Serves as a cushioning material and receives the bolt catcher, thereby blocking the transmission of stress from the spacer bolt to the mortar or the outer wall tile on the mortar. Therefore, defects such as cracks do not occur in the mortar applied to the outer wall surface of the concrete structure or the outer wall tile on the mortar.

FIG. 1 is an exploded perspective view of one embodiment of a connector / mortar bonding aid of the present invention. FIG. 2 is a perspective view of a circular lid constituting one embodiment of the connector / mortar bonding aid of the present invention, and corresponds to a view of FIG. 1 viewed from an opposite direction to the paper surface. FIG. 3 is a perspective view of a circular main body constituting one embodiment of the connector / mortar bonding aid of the present invention, which corresponds to a view of the one shown in FIG. FIG. 4A shows a projection provided on the inner surface side of a circular lid constituting one embodiment of the connector and mortar bonding aid of the present invention, and one embodiment of the connector and mortar bonding aid of the present invention. FIG. 4B is a cutaway perspective view showing a positional relationship with an end face of a bolt catcher to be constituted, and FIG. 4B is an enlarged view of a part of FIG. FIG. 5 is a view showing an example of use of the connector / mortar bonding aid of the present invention, and is a longitudinal sectional view when assembling a concrete formwork. FIG. 6 is a longitudinal sectional view of a state where the concrete formwork is removed from FIG. FIG. 7 is an exploded perspective view of another embodiment of the connector / mortar bonding aid of the present invention. FIG. 8A is a cutaway perspective view showing a positional relationship between a protrusion provided on the inner surface side of a circular lid and an end face of a bolt catcher, which constitutes another embodiment of the connector / mortar bonding aid of the present invention. FIG. 8B is an enlarged view of a part of FIG. 8A. 9A and 9B are explanatory views showing an assembling state of a conventional concrete formwork. FIG. 9A is a longitudinal sectional view at the time of assembling, and FIG. 9B is a longitudinal sectional view at the time of detaching. FIG. 10 shows an example of use of the mortar bonding aid disclosed in Patent Document 1. FIG. 10 (A) is a longitudinal sectional view before the mortar bonding aid is mounted, and FIG. 10 (B) is the same. FIG. 10 (C) is a longitudinal sectional view showing the state after the mortar is further applied.

  Hereinafter, embodiments of the present invention will be described, but various changes and modifications can be made without departing from the technical scope of the present invention.

  FIG. 1 is an exploded perspective view of one embodiment of a connector / mortar bonding aid of the present invention. In FIG. 1, 1 is a circular main body, 2 is a bolt catcher which can be inserted into the circular main body 1 and has a screw portion on the inside, and is screwed with a spacer bolt set in a concrete formwork. A circular lid body 4 that can be fitted with 1 is a form clamping bolt. A large number of loop portions 5 engaging with the mortar are radially arranged on the end face of the circular lid 3 on the side of the skeleton concrete surface, and a beard capable of preventing the mortar from entering the screw portion of the bolt catcher 2. A number of projecting ridges 6 are provided. Since many whisker-like protrusions 6 are entangled with the mortar, it is possible to prevent the mortar from entering the screw portion of the bolt catcher 2.

  Further, a part of the outer periphery of the flange 2a1 of the bolt catcher 2 is cut in the vertical direction as shown by 2b. In this way, cutting a part of the outer periphery in the vertical direction is called a D-cut, and it is preferable that the D-cut 2b is provided because unnecessary co-rotation can be prevented. Further, cutting off a part of two opposing locations (two locations 180 degrees apart) on the outer periphery of the flange 2a1 of the bolt catcher 2 in the vertical direction is called I-cut. Is more preferred because it can be further prevented.

  In order to fit the circular main body 1 and the circular lid 3, as shown in FIG. 3, claw portions 7 protruding slightly outward are provided at three places on the outer periphery of the circular main body 1. Have been. As shown in FIG. 2, small openings 8 that can receive the claw portions 7 are provided at three locations on the outer periphery of the circular lid 3. Further, as shown in FIG. 2, a plurality of projections 9 are formed on the inner surface side of the circular lid 3. Since the projection 9 is composed of a plurality of pieces, the projection 9 comes into contact with the bolt catcher 2 so that it is easily broken or broken.

  In FIG. 1, the claw portion 7 (FIG. 3) of the circular main body 1 is inserted into the circular main body 1 so that the bolt catcher 2 is inserted through the circular main body 1 and the circular main body 1 is covered with the circular lid 3. The circular body 1 and the circular lid 3 were fitted by pressing on the minute opening 8 of the body 3 (FIG. 2), and the spacer bolt set in the concrete form was screwed into the bolt catcher 2. At this time, as shown in FIG. 4A, a slight gap C (about 0.1 to 0. 0) is provided between the end face 2c of the flange 2a of the bolt catcher 2 and the projection 9 provided on the inner surface side of the circular lid 3. 5 mm), the gap C absorbs the extension of the bolt catcher 2. Even if the bolt catcher 2 extends beyond the length of the gap C, the protrusion 9 in contact with the bolt catcher 2 is damaged or broken, thereby serving as a cushioning material to receive the bolt catcher 2 and to receive the spacer bolt. The transmission of stress from the mortar to the outer wall tiles on the mortar or the mortar is interrupted. There is no slight gap C between the end surface 2c of the flange 2a of the bolt catcher 2 and the protrusion 9 provided on the inner surface side of the circular lid 3, and the protrusion 9 provided on the inner surface side of the circular lid 3 and the bolt catcher 2 Similarly, even if the end face 2c of the flange 2a abuts from the beginning, the projection 9 in contact with the bolt catcher 2 is similarly damaged or destroyed and serves as a cushioning material to receive the bolt catcher 2, and the mortar from the spacer bolt. Alternatively, the transmission of stress to the outer wall tile on the mortar is interrupted. In FIG. 4B, a hatched portion indicates a cut portion, and a protrusion 9 provided on the inner surface side of the circular lid 3 is tapered. Since the extension of the bolt catcher 2 is prevented by the protrusion 9, the transmission of stress from the spacer bolt set in the concrete form to the mortar or the outer wall tile on the mortar via the bolt catcher 2 is blocked. In addition, by providing the flange 2a of the bolt catcher 2 on the skeleton concrete surface side, the flange 2a can be received by the annular projection 10 inside the circular main body 1.

  FIG. 5 is a view showing an example of use of the connector / mortar bonding aid of the present invention, and is a longitudinal sectional view when assembling a concrete formwork. As described above, the circular main body 1 and the circular lid 3 are fitted together, and the bolt catcher 2 and the spacer bolt 11 are screwed together as shown in FIG. 5 to assemble the molds 12a and 12b. The form clamping bolt 4 is screwed into the bolt catcher 2 to tighten the form 12b.

When the assembling of the molds 12a and 12b is completed, concrete is poured into the concrete casting space between the molds 12a and 12b. When the poured concrete is hardened to form the skeleton concrete 13, the molds 12a and 12b are removed, and the mold fastening bolts 4 are rotated to be separated to perform the mold removing operation. Generally, the spacer bolts 11 are often arranged at a ratio of 4 / m ² per unit area of concrete.

  FIG. 6 is a longitudinal sectional view showing a state where the concrete formwork is removed from FIG. 5, and mortar is applied to the surface of the skeleton concrete 13 and the surface of the connector / mortar bonding aid. As the mortar used at this time, a mortar containing a nylon short fiber called a tough binder and adapted to a predetermined LT method is used. When applying the mortar, it is important to apply the mortar firmly to the loop portion 5. However, it is necessary to prevent the mortar from entering the screw portion of the bolt catcher 2. For this reason, as shown in FIG. 1, the end face 14 of the opening is narrowed, and a large number of ridges 6 are provided in the opening so as to prevent mortar from entering the screw portion of the bolt catcher 2. . Further, a tile is stuck on the mortar. In the present invention, as shown in FIG. 1, a large number of loop portions 5 engaging with the mortar are radially arranged on the end face of the circular lid 3, so that the mortar is hard to fall off.

  The connector and mortar bonding aid of the present invention is used as a connector between the spacer bolt 11 and the form clamping bolt 4, and is used as it is without removing it after hardening of concrete. In the present invention, since the flange 2a of the bolt catcher 2 is fixed to the mortar bonding aid main body, it is not left inside the concrete frame 13. In addition, since the operation of detaching the connector and the subsequent operation of attaching the mortar bonding aid are not required, the operation time for the pretreatment for preventing the mortar from falling off can be remarkably reduced.

  As described in paragraph 0028, the three claws 7 of the circular main body 1 are hooked on the three small openings 8 of the circular lid 3, and the circular main body 1 and the circular lid 3 are fitted by pressing. Is done. Then, it is considered that the adhesive strength of the mortar and the tile applied to the surface of the stiffened concrete concrete depends on the strength of the nail 7. Therefore, at the time of press fitting, as shown in FIG. 4A, the circular main body 1 does not entirely contact the circular lid 3, but the circular main body 1 is slightly round. When it comes into contact with the body 3 at an angle, the three claw portions 7 of the circular main body 1 are not received by the three small openings 8 of the circular lid 3, and only one claw portion 7 is very small. As a result of receiving by the opening 8, stress is concentrated on the claw portion 7, and the adhesive strength is reduced. Therefore, if three pins 15 are provided on the circular main body 1 as shown in FIG. 7, if the pins 15 are crushed when the circular main body 1 and the circular lid 3 are fitted by pressing, FIG. As shown in a), the crushed pin 15 becomes an obstacle, and the circular main body 1 and the circular lid 3 are kept at a fixed distance. As described above, since the pin 15 becomes an obstacle, the circular main body 1 is prevented from obliquely contacting the circular lid 3, and the three claw portions 7 of the circular main body 1 are connected to the circular lid 3. The adhesive strength of the mortar and the tile applied to the surface of the stiffened concrete body, which is received in the same manner at the three small openings 8 of the body 3, is equally applied to the three claw portions 7. Therefore, the adhesive strength does not decrease. For this purpose, the height of the pin 15 is preferably equal to or higher than the height H of the protrusion 9 shown in FIG.

  In FIG. 7, the number of the pins 15 is three, and the pins 15 are provided at equal intervals in the circumferential direction with the center of the circular main body 1 as the center of the circle. The number of pins 15 may be four or more as long as they are equally spaced in the circumferential direction. The number of pins 15 may be two. When two pins 15 are provided, it is preferable to provide the pins 15 in opposite directions. The position of the pin 15 in the radial direction is not particularly limited. In addition, since the effect described in paragraph 0033 cannot be obtained with one pin 15, it is preferable that the number of pins 15 is two or more. The pin 15 itself does not need to have strength, but as described in paragraph 0033, functions as a cushioning material for preventing the circular main body 1 from obliquely contacting the circular lid 3. Therefore, it is preferable that the number of pins 15 is large as long as unnecessary production cost is not increased.

  The resin used for manufacturing the connector / mortar bonding aid of the present invention is preferably a thermoplastic resin which is easily injection-molded, but may be a thermosetting resin if necessary. For example, as thermoplastic resin, nylon, polyphenylene sulfide (PPS), polyester, polyethylene, polypropylene, polystyrene, high impact polystyrene (HIPS), ABS resin, modified polyphenylene oxide (modified PPO), polyamide elastomer (for example, Toray Industries, Inc.) And “Pevacs” manufactured by Toray DuPont, Inc., and the like. However, concrete is alkaline, and among these, PPS resin and nylon resin which are excellent in alkali resistance and heat resistance are particularly preferable.

  Further, as these resins, a fiber reinforced resin mixed with short fiber reinforcing fibers such as glass fiber and carbon fiber may be used. In the case of a fiber reinforced resin, the adhesive strength of the mortar can be further improved, and the performance of preventing flakes can be further improved.

  It is preferable that the connector / mortar bonding aid of the present invention is designed so that the adhesive strength to mortar per piece is 50 kg / piece or more. In order to satisfy such characteristics, in the case of a loop shape, the dimensions of the locking portion are such that the loop thickness (diameter) is 0.1 to 3.0 mm and the loop diameter is 2.0 to 10.0 mm. Is preferred.

  INDUSTRIAL APPLICABILITY The present invention is suitable as a connector and mortar bonding aid for a concrete structure.

DESCRIPTION OF SYMBOLS 1 Circular main body 2 Bolt catcher 2a, 2a1 Flange 2b D cut 2c End face 3 Circular lid 4 Form clamping bolt 5 Loop part 6 Ridge 7 Claw part 8 Small opening 9 Protrusion 10 Ring projection 11 Spacer bolt 12a, 12b type Frame 13 Frame concrete 14 End face 15 pin

Claims (3)

  What is claimed is: 1. A mortar adhesive aid applied to a surface of a skeleton concrete, comprising: a circular main body; a spacer bolt which can be inserted into the circular main body, has a screw portion inside, and is set in a concrete formwork; A bolt catcher to be screwed in, a circular lid capable of being fitted to the circular main body, and a form clamping bolt, a number of which engage the mortar on an end face of the circular lid on the side of the concrete surface of the frame. The loop portions are arranged in parallel or radially, a protrusion is provided on the inner surface side of the circular lid, a circular body and a circular lid are fitted by inserting a bolt catcher into the circular body, When the spacer bolt is screwed with the bolt catcher, there is a slight gap between the projection and the end face of the bolt catcher, or that the projection and the end face of the bolt catcher abut. Connector also serves as mortar adhesion aid to butterflies.   On the end face of the circular lid body on the side of the skeleton concrete surface, apart from a number of loop portions engaging with the mortar, a ridge for preventing mortar from entering the screw portion of the bolt catcher is provided. The connector / mortar bonding aid according to claim 1.   The mortar bonding aid for a connector according to claim 1 or 2, wherein a plurality of projections are provided on the inner surface side of the circular lid.