JP3989895B2 - Construction method of crack-induced joint and crack-induced joint - Google Patents

Description

  The present invention relates to a crack-induced joint construction method and a crack-induced joint, and in particular, a crack-induced joint construction method and a crack-induced joint that eliminates unnecessary extra strikes and removes adhesion to a concrete wall by providing a uniform and thin release material. Concerning joints.

  In order to prevent complaints of water leakage from the outer wall, and to assure quality that avoids an increase in repair costs and a decline in credit, measures are taken to ensure that cracks are induced at joints that have been waterproofed. As a countermeasure, there is a method to disperse cracks with reinforcing bars, but since future repairs are necessary for durability and aesthetic issues, a method of concentrating cracks systematically by providing crack-inducing joints is desirable. .

  Crack-inducing joints induce cracks in the outer walls of reinforced concrete and earthquake resistant walls due to dry shrinkage of concrete, and maintain joints with a depth of about 20 mm in the lateral direction at intervals of 3 to 4 m. In order to compensate for the deficiency rate deficiency only at the outer wall joints of reinforced concrete, the effect of cracking induction is enhanced by embedding foreign materials that become cross-sectional defect materials inside the walls in relation to the joints. This prevents cracks from appearing in the wall, making it difficult to see the wall, and rainwater invading and rusting the cracked steel bars to peel and drop the outer wall concrete.

  As a method of embedding foreign matter that becomes a cross-sectional defect material inside the wall, steel pipes, dowel bars, keystones that have lost their adhesion to concrete by inserting a PVC pipe at a position corresponding to the outer wall joint or rust prevention treatment etc. Shear keys such as plates, expanded metal, or steel nets are arranged between the reinforcing bars, but the following proposals have been made to actively insulate the concrete.

As shown in FIG. 4, the proposed reinforced concrete wall 1 has a crack-inducing joint 2. The concrete wall 1 has rebars 3 and 3 arranged on both the inner and outer sides, and a crack-inducing joint 2 having a predetermined depth is provided on the outer surface. In the concrete, a plurality of crack-inducing bars 4 parallel to the induction joints are embedded in the middle part of the thickness along the induction joints 2 in close contact with the holding bars 5 that are installed between the internal and external rebars 3 and 3. Has been. The crack-inducing bar 4 is made by winding a tape 6 with adhesive on one side such as gum tape, vinyl tape, paper tape, craft tape, etc. This is dealt with by utilizing the releasability of the surface of the material or by applying a releasable or releasable drug or resin to the surface of the substrate. (For example, see Patent Document 1)
However, providing joints on the outside of the building and embedding inducing materials such as cross-sectional defects in the concrete causes a reduction in seismic performance by creating defective parts in terms of seismic resistance, even if the crack inducing effect increases. Therefore, we want to reduce the cross-sectional defect material. In particular, in the case of a seismic wall, the joint depth for forming joints is ensured by increasing hits, and in order to obtain appropriate joints, the extra hits become large and uneconomical.

  In addition, as described above, there is the following problem when embedding a vinyl tape-wrapped reinforcing bar in a concrete wall as a crack-inducing joint.

1) The adhesive is attached to the vinyl tape and the vinyl tape overlaps, so that the coating thickness is increased and the seismic performance is lowered.
2) The surface of the vinyl tape wound reinforcing bar is not smooth due to the overlap of the vinyl tape, and the adhesion between the vinyl tape and the concrete is not completely removed, so the cracking induction performance is inferior.
3) Since it takes a long time to wind with less overlap of vinyl tape, the workability is poor.

As described above, the conventional crack-inducing joints are uneconomical due to the increased hitting in order to make them suitable joints. In the case of a seismic wall, the coating of the material is not smooth and the separation from the concrete is not complete, so the crack-inducing performance is inferior and the construction work is difficult because the covering work on the cross-section defect material is difficult. In particular, these problems became prominent, and therefore a particularly rapid improvement was desired.
Japanese Patent Laid-Open No. 6-248731 (paragraph numbers “0008”, “0013” to “0016”, FIG. 2)

  The present invention is proposed in view of the above-mentioned problems, and in order to solve the problems, by disposing a cross-sectional defect material provided with a uniform and thin release material while eliminating unnecessary extra striking, concrete is provided. We provide a simple and efficient crack-inducing joint construction method and a crack-inducing joint that can reliably exert the crack-inducing function by ensuring adhesion and removal from the wall.

  The crack-inducing joint construction method according to the present invention is a crack-inducing joint construction method in which a notch is provided outside the wall and a cross-sectional defect material is embedded inside the concrete wall. After tightly bonding the material to the concrete wall rebar, heat shrink the tube to heat shrink to adhere to the cross-sectional defect material, or cover the cross-sectional defect material with heat shrink tube appropriately and then heat shrink to attach the heat shrink tube The cross-section defect material is characterized in that the cross-section defect material is tightly connected to the reinforcing bar of the concrete wall. By arranging and removing the adhesion to the concrete wall reliably, a crack-inducing joint is formed by simple construction.

  In addition, the crack-inducing joint according to the present invention is provided with a notch on the outside of the wall, and a cross-sectional defect material in which a heat-shrinkable tube is covered inside the concrete wall by the above-described crack-inducing joint construction method in relation to the notch. The basic feature is that the overall defect rate is 20% or more due to the notch on the outside of the wall and the section defect material embedded in the concrete wall. The adhesion and removal of the defective material is ensured by the covering of the heat shrinkable tube to ensure the function of the crack-inducing joint.

  According to the present invention, the crack-inducing joint is constructed by attaching a heat-shrinkable tube with a cross-sectional defect material to a concrete wall reinforcing bar and then heat-shrinking the heat-shrinkable tube to closely contact the cross-sectional defect material. The material is covered with a heat-shrinkable tube as appropriate and then heat-shrinked, and the cross-sectional defect material in which the heat-shrinkable tube is brought into close contact with the reinforcing bar of the concrete wall eliminates unnecessary extra striking and reduces costs. A crack-induced joint can be easily constructed by efficiently providing a cross-sectional defect material covered with a uniform thin heat-shrinkable tube by simply passing the rebar cut to length through the heat-shrinkable tube and heating it. It is effective.

  In addition, the crack-inducing joint according to the present invention is provided with a notch on the outside of the wall, and a cross-sectional defect material in which a heat-shrinkable tube is covered inside the concrete wall by the above-described crack-inducing joint construction method in relation to the notch. Based on the construction, the following effects are exhibited by constructing the overall defect rate by the notch outside the wall and the sectional defect material embedded in the concrete wall to 20% or more.

1) Since the heat-shrinkable tube is very thin, the compressive force acting at the time of an earthquake can be transmitted without any problem and there is no deterioration in the seismic capacity.
2) Since the heat-shrinkable tube has no seam and has a smooth surface, it can remove the adhesive force with concrete and increase the cracking induction performance.

The crack-inducing joint according to the present invention is constructed by the crack-inducing joint construction method of the present invention, which will be described later. The cross-sectional defect material covered with the heat-shrinkable tube is embedded by the above construction method, and the total defect rate due to the external defect and the cross-sectional defect material embedded in the concrete wall is configured to be 20% or more.
In the following, an embodiment of the crack-inducing joint of the present invention will be described in detail with reference to the drawings. However, in order to facilitate understanding of the difference from the conventional example, the same parts as those in the conventional example are the same. It is expressed by a sign.

FIG. 1: has shown embodiment regarding the crack induction joint of this invention, The longitudinal cross-sectional view (b) which looked at the plane sectional view (a) and the plane sectional view (a) from (b)-(b) arrow. is there.
As in the conventional example, the reinforced concrete wall 1 in the present embodiment is provided with crack-inducing joints 2 having a predetermined depth on the outer surface, and grid-like reinforcing bars 3 and 3 arranged on both the inner and outer sides of the concrete wall 1. In the meantime, as shown in FIG. 1A, the cross-sectional defect material 7 is buried in the concrete in a state where the cross-sectional defect material 7 is stretched tightly.

  As shown in FIG. 1B, the cross-sectional defect material 7 is composed of a crack-inducing muscle 4 covered with a heat-shrinkable tube 8 ′ and a holding muscle 5 equipped with the crack-inducing muscle 4. Consisting of 2 with the induction joint 2 in the center of the thickness, the total defect rate is 20% or more due to the induction joint 2 outside the wall and the cross-sectional defect material 7 embedded inside the concrete wall. is doing.

  The configuration of the cross-sectional defect material is not limited to the above-described embodiment. For example, the crack-inducing muscle 4 covered with the heat-shrinkable tube 8 ′ is latticed in a predetermined number without being attached to the holding muscle 5. It is also possible to fasten and arrange between the reinforcing bars 3 and 3 by a binding wire, and the attachment means is arbitrary.

  The heat-shrinkable tube 8 of the crack-inducing muscle 4 can be easily adhered by simply heating it with an industrial dryer after the construction is covered with the crack-inducing muscle 4, and the thickness is about 0.1 mm. Since the surface is smooth and the surface is seamless, the cracking induction performance is ensured while ensuring the seismic performance by transmitting the compressive force acting in the event of an earthquake without any problem and reducing the adhesion to the concrete. Has improved.

Therefore, when the surface of the cross-sectional defect material 7 is formed as a seamless smooth surface to reduce the adhesion to the concrete, even in the earthquake resistant wall, the induced joints outside the wall and the cross-sectional defect material inside the concrete wall It has been confirmed that a sufficient crack-inducing function can be exhibited by configuring the total defect rate by 20% or more, which solves the problem of inducing cracks in earthquake-resistant walls.
Next, the cracking induction joint construction method according to the present invention for constructing the above-described crack induction joint will be described.

According to the present invention, the crack-induced joint construction method is such that the heat-shrinkable tube is heat-shrinked after the cross-sectional defect material appropriately covered with the heat-shrinkable tube is bonded to the reinforcing bar of the concrete wall, or the cross-sectional defect material is adhered. The material with a heat-shrinkable tube is covered with a heat-shrinkable tube, and then the heat-shrinkable tube is in close contact with the reinforcing bar of the concrete wall. Efficiently providing a cross-sectional defect material covered with a uniform thin heat-shrinkable tube by a simple method of heating after covering the reinforcing bar, eliminating wasteful additional strikes and proof stresses and reducing cracking and joints that induce cracks Is simply constructed.
In the following, the embodiment of the cracking joint joint construction method of the present invention will be described in detail with reference to the drawings. However, in order to facilitate understanding of the difference from the conventional example, the same part as the conventional one will be described. Are represented by similar symbols.

  FIG. 2 shows an embodiment relating to the first construction method of the crack-inducing joint of the present invention, and a process diagram (a) for binding a cross-sectional defect material appropriately covered with a heat shrinkable tube to a reinforcing bar of a concrete wall; It is process drawing (b) which heat-shrinks a heat-shrink tube after that and makes it closely_contact | adhere to a cross-sectional defect | deletion material.

  In the present embodiment, the cross-sectional defect material 7 is composed of a crack-inducing muscle 4 and a holding muscle 5 equipped with the crack-inducing muscle 4 by welding or binding wires, and a heat-shrinkable tube 8 is provided on the crack-inducing muscle 4. As shown in FIG. 2A, the covered holding bars 5 are bridged between the lattice-like reinforcing bars 3 and 3 and are fastened together by welding or binding wires.

  Next, the coated heat-shrinkable tube 8 is heat-shrinked so as to be disposed in the entire region of the crack-inducing muscle 4 by heating of the dryer 9 or the like. All the crack-inducing muscles 4 are covered with an intimate heat-shrinkable tube 8 '.

  FIG. 3 shows an embodiment relating to the second construction method of the crack-inducing joint of the present invention, and is a process diagram in which a heat-shrinkable tube appropriately covered with a cross-sectional defect material is brought into close contact with the cross-sectional defect material by subsequent heat shrinkage. It is process drawing (b) which bind | concludes the cross-sectional defect | deterioration material which contact | adhered (a) and the heat contraction tube to the reinforcing bar of a concrete wall.

  In the present embodiment, the cross-sectional defect material 10 is composed of a crack-inducing muscle 4 and a holding muscle 5 equipped with the crack-inducing muscle 4 by welding or binding wires, and a heat-shrinkable tube 8 is provided on the crack-inducing muscle 4. After the coating, as shown in FIG. 3A, the coated heat-shrinkable tube 8 is heat-shrinked so as to be disposed in the entire area of the crack-inducing muscle 4 by heating with a dryer 9 or the like. The cross-sectional defect material 10 is covered with a heat-shrinkable tube 8 ′ in which all the crack-inducing muscles 4 are in close contact with each other by continuing this process sequentially.

  Next, in the cross-sectional defect material 10 after the entire crack-inducing muscle 4 is covered with the heat-shrinkable tube 8 ′, the holding bars 5 constituting the lattice-shaped reinforcing bars 3 and 3 are arranged as shown in FIG. It is stretched over and is fastened by welding or binding wires.

  Therefore, since the heat-shrinkable tube 8 can be coated on the crack-inducing muscle 4 at the stage of the cross-sectional defect material 10 that is easy to handle, the heat-shrinkable tube 8 can be covered more easily and completely insulated from the concrete. This ensures cracking induction.

  As described above, the crack induction joint method according to the present invention and the crack induction joint according to the present invention are configured as described in the respective embodiments. By providing a heat-shrinkable tube that passes through the triggering muscle uniformly and thinly by a simple method of heating, the crack-inducing joints can be easily constructed, and the crack-inducing performance is improved while reducing the seismic capacity.

  The present invention solves the cracking problem of reinforced concrete outer walls and earthquake-resistant walls, eliminates unnecessary extra striking, reduces costs, and arranges a cross-sectional defect material provided with a uniform and thin release material to remove adhesion to concrete. It is surely induced at a position where cracks caused by drying shrinkage of the concrete are assumed.

Embodiment of the crack-induced joint according to the present invention Process drawing which shows 1st Embodiment regarding the construction method of the crack induction joint by this invention Process drawing which shows 2nd Embodiment regarding the construction method of the crack induction joint by this invention Conventional form of crack-induced joints

Explanation of symbols

1 Reinforced concrete wall, 2 Crack-inducing joints, 3 Reinforcing bars
4 crack-inducing muscles, 5 retaining muscles, 6 tapes, 7 cross-sectional defect material,
8, 8 'heat shrinkable tube, 9 dryer, 10 cross-sectional defect material,

Claims (4)

A crack-inducing joint construction method in which a notch is provided outside the wall and a cross-sectional defect material is embedded inside the concrete wall, and the cross-sectional defect material appropriately covered with a heat-shrinkable tube is connected to the reinforcing bar of the concrete wall. Then, the method for constructing a crack-inducing joint characterized in that the heat-shrinkable tube is heated and shrunk to adhere to the cross-sectional defect material. A crack-inducing joint construction method in which a notch is provided outside the wall and a cross-sectional defect material is embedded inside the concrete wall, and the heat-shrinkable tube is appropriately covered with the heat-shrinkable tube, and then the heat shrinkage. A crack-induced joint construction method characterized in that a cross-section defect material with a tube in close contact is tightly connected to a reinforcing bar on a concrete wall. A notch is provided outside the wall, and a cross-sectional defect material in which a heat-shrinkable tube is covered by the crack-inducing joint construction method according to claim 1 or 2 is embedded in the concrete wall in relation to the notch. Crack-induced joints. The crack-inducing joint according to claim 3, wherein a total defect rate due to a notch outside the wall and a cross-sectional defect material embedded in the concrete wall is configured to be 20% or more.

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