JP2008014053A - Shearing reinforcement structure, shearing reinforcement method, and composite capsule for shearing reinforcement - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high quality shearing reinforcement structure and a shearing reinforcement method which easily enable reinforcement of a shearing force and impartation of a bending toughness property to an existing concrete structure, and to provide a composite capsule for the shearing reinforcement used preferably in the structure and the method. <P>SOLUTION: The shearing reinforcement structure includes a side wall 20 which is an existing reinforced concrete structure and a composite capsule 10 for the shearing reinforcement arranged in and integrally fixed to a reinforcing member insertion hole 21 formed in the side wall 20. The composite capsule 10 for the shearing reinforcement comprises a hardened body 11 of a cement-based mixed material formed to have a column-like shape, and a shearing reinforcement member 12 internally fitted to the hardened body 11. The shearing reinforcement member 12 is structured with a linear material 12a and anchor members 12b, 12b formed on both ends of the linear material 12a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a shear reinforcement structure of an existing reinforced concrete structure on which a shearing force acts, a shear reinforcement method, and a composite capsule for shear reinforcement used therein.

Some existing reinforced concrete structures have a high probability of shear failure when subjected to large seismic forces. In particular, in various facilities such as subways and water and sewage purification facilities designed and constructed before the Great Hanshin Earthquake, the walls, slabs, and bridges of reinforced concrete box culverts and reinforced concrete underground structures that make up the structure There are many cases where shear reinforcement is not installed in the wall type piers, etc., and the lack of shear strength against level 2 earthquake motion and the lack of toughness performance due to bending moment have been clarified from the results of various seismic diagnostics. It is pointed out that there is a need for seismic reinforcement.
In recent years, such reinforced concrete structures may be reinforced so as not to cause shear failure.

  These reinforced concrete structures are mostly embedded in the ground due to their functional characteristics. When reinforcing after construction, the side walls and bottom slabs of the structural frame cannot be reinforced from the outer surface side. The reinforcement is unavoidable only from the inner surface side. Here, in this specification, the “outer surface” refers to the surface facing the ground of the reinforced concrete structure surface material or plate material, and the “inner surface” refers to the outer surface of the same surface material or plate material. This is the surface that faces the surface and does not face the natural ground.

  Conventionally, reinforcement methods for these reinforced concrete structures include the thickening method in which the main reinforcement and the distribution reinforcing bars are arranged along the surface of the reinforced concrete structure and the concrete is placed, or the steel plate around the reinforced concrete structure. A steel plate winding method or the like in which a gap between a reinforced concrete structure and a steel plate is filled with a filler such as mortar or resin has been adopted.

  However, these methods cause various inconveniences such as an increase in the thickness of the face material and the plate material after reinforcement and a decrease in the internal cross section of the frame (for example, in the case of a water and sewage purification facility). In some cases, water storage capacity and processing capacity decrease, and in the case of a subway, the construction limit will not be satisfied, and it may become unusable. In addition, the thickening method increases the main reinforcement and improves the shear strength, but also increases the bending strength. Therefore, the request to shift the shear pre-breaking type to the bending pre-breaking type after reinforcement is realized. It was difficult to do.

  In addition, large lifting machines are required for carrying in and assembling reinforcing members such as reinforcing steel bars and steel plates, and in the limited space such as underground structures and bridges, these lifting machines are limited and construction is difficult. There was a case. In addition, in the case of shear reinforcement in road tunnels and railway tunnels that are in service, the conventional reinforcement method described above is required for rapid construction within a limited time zone at night due to restrictions on traffic volume and train operation. However, there were cases where construction was not possible.

  Therefore, in order to solve the above-mentioned problems, as a method of shear reinforcement for an existing reinforced concrete structure, an insertion hole is drilled in the member thickness direction of the face material or plate material of the reinforced concrete structure, and the shear reinforcement bar is provided in this insertion hole. May be placed and filled with grout material. However, in this shear reinforcement method, when a straight reinforcing bar is used as the shear reinforcement, the fixing performance is higher than that of a shear reinforcement with a hook at the end, which is provided when a new reinforced concrete structure is constructed. It is inferior and the effect of reinforcement will be limited.

Therefore, as shown in FIG. 6, the applicant assigns the shear reinforcement member 110 in which the fixing members 112, 112 are fixed to both ends of the shear reinforcement reinforcing bar 111 to the reinforcement member insertion hole 121 formed in the reinforced concrete structure 120. By providing and integrating via the filler 130, the shear reinforcement structure 100 which is excellent in fixing property and enhances the shear reinforcement effect has been disclosed and has been put into practical use (see Patent Document 1).
JP 2005-105808 A

When constructing the shear reinforcement structure 100, when filling the insertion hole of the filler 130 after inserting the shear reinforcement member 120 into the reinforcement member insertion hole 121, the shear reinforcement member 110 and the reinforcement member insertion hole 121 are performed. Therefore, it is necessary to perform the work carefully so that the filling is not incomplete, and the work efficiency may be deteriorated.
On the other hand, when the shear reinforcement member 110 is inserted after the filler 130 is filled in the reinforcement member insertion hole 121, the shear reinforcement member 110 is carefully and slowly so as not to entrain air into the back surface of the fixing member 112. Need to be inserted. For this reason, there is a case where there is a problem that work is troublesome.

  Moreover, the filling work of the filler 130 on site and the curing of the filler 130 may hinder the shortening of the construction period.

  The present invention has been made in order to solve the above-described problems, and provides a shear reinforcement structure capable of imparting shear force reinforcement and bending toughness performance of an existing concrete structure in a simple and high quality manner. It is another object of the present invention to provide a shear reinforcement method and a composite capsule for shear reinforcement that is preferably used in these methods.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a shear reinforcement in which an existing reinforced concrete structure and a reinforcing member insertion hole formed in the reinforced concrete structure are arranged and fixed integrally. A composite material capsule, wherein the composite capsule for shear reinforcement is a hardened body of cementitious mixed material formed in a columnar shape, and a shear reinforcing member disposed inside the hardened body It is characterized by consisting of.

  In such a shear reinforcement structure, since the composite capsule for shear reinforcement in which the shear reinforcement member is disposed is disposed inside the existing reinforced concrete structure, the shear strength of the reinforced concrete structure is improved. In addition, since the cement-reinforced mixed material and the shear reinforcing member are integrally formed in advance, the shear reinforcing mixed capsule is filled with filler, grout, etc. in the reinforcing member insertion hole when placed in the reinforced concrete structure. It is possible to carry out easily without requiring. Therefore, it is possible to shorten the construction period.

  Further, since the shear reinforcement structure of the present invention is integrated with the shear reinforcement member and the concrete of the reinforced concrete structure, the shear reinforcement structure is against the tensile tensile stress generated when an out-of-plane shear force is generated. The member and the reinforced concrete structure integrally resist. Therefore, the shear strength of the existing reinforced concrete structure can be improved, and the failure mode due to an earthquake or the like can be shifted from brittle failure to tough failure.

  Further, according to the shear reinforcement structure of the present invention, the shear reinforcement member (composite capsule for shear reinforcement) is directly placed inside the structure (face material or plate material) without increasing the concrete thickness of the reinforced concrete structure. By embedding in the structure, an increase in shear strength and toughness performance can be realized efficiently, so that it is possible to prevent the occurrence of inconveniences such as a decrease in the internal cross section of the housing after reinforcement. In addition, since the main reinforcing bars are not increased, the out-of-plane shear strength can be improved without increasing the bending strength. Therefore, at the time of a level 2 earthquake, a reinforced concrete structure that may be a shear preceding failure type can be transferred to a bending preceding failure type.

  Here, the structure to be reinforced by the present invention is a structure that requires shear reinforcement, and can be applied to various existing reinforced concrete structures. Moreover, what was hit on the spot may be sufficient and what was precast in the factory etc. may be sufficient.

  The invention according to claim 2 is a shear reinforcement method for an existing reinforced concrete structure in which a shearing force is applied, wherein the reinforcing member insertion hole extends from one surface side to the other surface side of the existing reinforced concrete structure. A shearing step comprising: a step of injecting an adhesive into the reinforcing member insertion hole; a hardened body of cementitious mixed material formed in a columnar shape; and a shear reinforcing member disposed inside the hardened body And inserting the reinforcing composite capsule into the reinforcing member insertion hole from one surface side of the existing reinforced concrete structure.

  According to this shear reinforcement method, the shear reinforcement member is disposed in the reinforced concrete structure only by inserting the composite capsule for shear reinforcement in which the shear reinforcement member is disposed in advance into the reinforcement member insertion hole into which the adhesive is injected. Is done. Therefore, the filling and curing of the filler are omitted, and the labor and time required for the construction can be shortened.

  In the shear reinforcement method, if the composite capsule for shear reinforcement is inserted into the reinforcement member insertion hole while rotating in the circumferential direction, the adhesive goes to the entire gap between the composite capsule for shear reinforcement and the reinforcement member insertion hole. Therefore, it is preferable.

  The invention according to claim 4 is characterized by comprising a hardened body of a cement-based mixed material formed in a columnar shape and a shear reinforcement member disposed inside the hardened body.

  According to such a composite capsule for shear reinforcement, it becomes possible to improve the shear strength of this reinforced concrete structure simply by inserting it into an insertion hole formed in an existing reinforced concrete structure and integrating it through an adhesive. Is preferable. In addition, conventionally, the labor and time required for filling and curing the filler can be saved, and the construction period can be shortened. In addition, it is possible to construct a high-quality shear reinforcement structure without involving air.

  In addition, if a groove is formed on the surface of the cured body of the composite capsule for shear reinforcement, the adhesive performance (adhesion strength) between the composite capsule for shear reinforcement by the adhesive and the insertion hole is improved. Is further improved.

In the composite capsule for shear reinforcement, if the cement-based mixed material is grout material or mortar, the reinforcement effect is improved by the integration of the shear reinforcement member and the reinforced concrete structure, which is preferable.
In addition, if the cement-based mixed material is a fiber-reinforced mixed material in which fibers are mixed in a cement-based matrix, the shear reinforcing composite capsule itself has high rigidity, and the reinforcing effect is further improved.

  In the composite capsule for shear reinforcement, the shear reinforcement member may be composed of a wire and a fixing member formed at both ends of the wire and having a width larger than the diameter of the wire. Further, the fixing member may be constituted by a nut or a plate-like member having a width larger than the diameter of the wire. Further, the wire is made of a reinforcing bar, and the fixing member is formed in a width of 120% to 130% with respect to the diameter of the wire by hitting or pressing in the axial direction with the end of the wire heated. Protruding portions may be used.

  Further, in the shear reinforcement member, if a fixing member having a cross-sectional shape larger than that of the shear reinforcement reinforcing bar is provided at the base end portion and the distal end portion of the shear reinforcement reinforcing rod which is a wire, the fixing effect of the shear reinforcement member is enhanced. In addition, the tensile resistance of the shear reinforcing reinforcement and the compressive stress generated in the concrete inside the fixing member can improve the shear strength and the toughness performance more effectively. Here, the wire rod is not limited to a deformed bar or a round steel rod, and any wire rod such as a carbon wire, a steel rod, a PC steel strand, etc. can be applied.

As cement-based mixed materials, cement, pozzolanic fine powder and silica stone powder, silica fume, dredged sand with a particle size of 3 mm or less, sand with a particle size of 3 mm or less, and water in a high-performance water reducing agent The cement matrix obtained by mixing 175 to 180 kg (water cement ratio of about 20 to 22%) as the amount of water (per finished concrete volume of 1 m ³ ) has a diameter of 0.1 to 0.3 mm and a length of If a fiber reinforced cementitious mixed material in which steel fibers of 8 mm to 16 mm are mixed at 1% or more with respect to the volume of the cementitious matrix, a highly rigid fixing effect is realized.

  According to the shear reinforcement structure, the shear reinforcement method, and the composite capsule for shear reinforcement according to the present invention, it is possible to express a predetermined shear strength and impart high toughness performance to an existing reinforced concrete structure simply and with high quality. It becomes.

  A preferred embodiment of the reinforcing method of the present invention will be described in detail with reference to the drawings. In addition, the following demonstrates the case where the side wall of the existing reinforced concrete structure embed | buried in the underground ground is shear-reinforced. In the following description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted.

  FIG. 1 is a cross-sectional view showing a shear reinforcement structure according to this embodiment. 2A and 2B are diagrams showing the composite capsule for shear reinforcement of the present embodiment, in which FIG. 2A is a perspective view, FIG. 2B is a cross-sectional view, and FIG. 2C is a perspective view showing details of a shear reinforcement member. FIGS. 3A to 3C are perspective views showing modifications of the composite capsule for shear reinforcement. 4A to 4E are perspective views showing modifications of the fixing member of the shear reinforcement member. FIGS. 5A to 5D are cross-sectional views showing respective construction stages of the shear reinforcement method according to the present embodiment.

  As shown in FIG. 1, the shear reinforcement structure 1 according to the present embodiment is disposed inside a side wall 20 of an existing reinforced concrete structure and a reinforcing member insertion hole 21 formed in the side wall 20 and fixed integrally. And a composite capsule 10 for shear reinforcement.

The side wall 20 is a reinforced concrete member in which main reinforcing bars 22 and distribution reinforcing bars 23 are arranged at predetermined intervals. And the reinforcing member insertion hole 21 is based on the arrangement diagram at the time of construction of the side wall 20 and the information of the nondestructive test so that the main reinforcement 22 and the distribution reinforcement 23 are not damaged at the time of drilling. The horizontal interval is the same as the main reinforcing bar 22 and the vertical interval is the same as the distribution reinforcing bar 23, and is formed at the approximate center of both reinforcing bars.
In addition, although this embodiment demonstrated the case where the side wall of the existing reinforced concrete structure embed | buried in the underground ground was demonstrated, the structure of the existing reinforced concrete structure which performs reinforcement is limited to surface materials, such as a side wall. For example, a plate material such as a floor slab or a ceiling slab may be used.

As shown in FIG. 1, the reinforcing member insertion hole 21 is formed by drilling from the inner surface side of the side wall 20. The depth of the reinforcing member insertion hole 21 is formed to the vicinity of the main reinforcing bar 22 and the distribution reinforcing bar 23 on the outer surface side (natural ground G side).
Needless to say, the depth of the reinforcing member insertion hole 21 is not limited and may be set as appropriate. For example, it may be formed deeper than the position of the main reinforcing bar 22 on the outer surface side so that the fixing member on the front end side of the shear reinforcing member 12 can ensure the same covering as the main reinforcing bar 22.

The reinforcing member insertion hole 21 is formed in a circular cross section, and the diameter thereof is an adhesive used for the integration of the reinforcing member insertion hole 21 and the shear reinforcing composite capsule 10 between the reinforcing reinforcing member insertion hole 21 and the shear reinforcing composite capsule 10. A slight gap is formed so that the agent can be filled.
Needless to say, the cross-sectional shape of the reinforcing member insertion hole 21 is not limited to a circular shape, and may be appropriately set according to the cross-sectional shape of the composite capsule 10 for shear reinforcement.

  As shown in FIGS. 1 and 2, the composite capsule 10 for shear reinforcement includes a hardened body 11 of a cement-based mixed material formed in a columnar shape, and a shear reinforcing member 12 disposed inside the hardened body 11. Are integrally configured in advance. In addition, in this embodiment, although the hardening body 11 shall be formed in a column shape, if the shape of the hardening body 11 is a column shape, it will not be limited, For example, it forms in a square pillar and other polygonal notes. It may be.

The length of the cured body 11 (shear reinforcing composite capsule 10) is substantially the same as the depth of the reinforcing member insertion hole 21, and is longer than the entire length of the shear reinforcing member 12. Is arranged in the reinforcing member insertion hole 21 so that the base end surface (inner surface side surface) of the shear reinforcing composite capsule 10 is flush with the inner surface side surface of the side wall 20. The length of the cured body 11 is not limited, and may be shorter than the depth of the reinforcing member insertion hole 21, for example.
The cured body 11 has a diameter larger than the width of the fixing member 12 b of the shear reinforcement member 12 and is formed in a state of completely covering the shear reinforcement member 12.

  In this embodiment, the hardened body 11 itself has high tensile strength and tensile toughness by using a fiber-reinforced mixed material in which fibers are mixed in a cementitious matrix as the cement-based mixed material constituting the hardened body 11. And As a result, the composite capsule for shear reinforcement exhibits a higher tensile strength.

The fiber-reinforced mixed material according to the present embodiment includes cement, pozzolanic fine powder and silica stone powder, silica fume, dredged sand having a particle size of 3 mm or less, sand having a particle size of 3 mm or less, and a high-performance water reducing agent. And a cement matrix obtained by mixing 175 to 180 kg (water cement ratio is about 20 to 22%) as a unit water amount (per 1 m ^{3 of} finished concrete volume) with a diameter of 0.1 to 0.3 mm In addition, a fiber-reinforced cement-based mixed material is used in which steel fibers having a length of 8 to 16 mm are mixed with 1% or more of the cement-based matrix volume. As the steel fiber, one having a tensile yield strength of 2600 to 2800 N / mm ² is used. This fiber-reinforced mixed material has the following characteristics: φ5 × 10 cm specimen compressive strength 150-220 MPa, tensile strength 8-20 MPa, 4 × 4 × 16 cm specimen bending strength 25-45 MPa, elastic modulus 35-55 GPa. Yes.

In the present embodiment, a fiber-reinforced mixed material is used as the cement-based mixed material constituting the cured body 11, but only for the integration of the shear reinforcing member 12 and the reinforcing member insertion hole 21. In that case, grout material, mortar (compressive strength 60 N / mm ² ) or the like may be used as the cement-based mixed material.

  As shown in FIG. 2A, the cured body 11 according to the present embodiment has a plurality (three in the present embodiment) of grooves 11a, 11a, 11a formed on the outer peripheral surface (front surface) along the circumferential direction. The joint of the composite capsule 10 for shear reinforcement by the adhesive 30 and the reinforcing member insertion hole 21 is improved. Needless to say, the number and shape of the grooves 11a are not limited. For example, as shown in FIG. 3A, as the grooves 11a formed on the outer peripheral surface of the cured body 11, a plurality (six in FIG. 3A) of grooves 11a, 11a,... May be formed. Further, as shown in FIG. 3B, two intersecting spiral grooves 11a and 11a may be formed. Although not shown, one spiral groove 11a may be formed, and a plurality of depressions (small holes) 11b are formed as in the cured body 11 shown in FIG. The same effect can be obtained even if the outer peripheral surface of the cured body 11 has irregularities instead of grooves.

  As shown in FIGS. 2B and 2C, the shear reinforcing member 12 includes a wire 12a and fixing members 12b formed at both ends of the wire 12a.

  In this embodiment, a deformed reinforcing bar is used as the wire 12a. In addition, it cannot be overemphasized that the material which comprises the wire 12a is not limited to a deformed reinforcing bar, For example, you may use a threaded reinforcing bar, a steel rod, PC steel strand, a carbon wire etc.

  The total length of the shear reinforcing member 12 is shorter than the total length of the shear reinforcing composite capsule 10, and the width of the fixing member 12b is smaller than the outer diameter of the shear reinforcing composite capsule 10 (cured body 11). Yes. That is, the composite capsule 10 for shear reinforcement is formed in a state where the shear reinforcement member 12 is completely covered by the cured body 11. In the present embodiment, the total length of the shear reinforcement member 12 is configured to be approximately the same as the distance between the main reinforcing bars 22 in the side wall thickness direction. It is not limited.

  As shown in FIG. 2C, the fixing member 12b is formed of a steel plate-like member having a width larger than the diameter of the wire 12a.

The fixing member 12b is made of a square steel plate having a thickness of 30% to 120% of the diameter of the first shear reinforcing bar 22 and a width of about 200% to 300% of the diameter of the reinforcing bar 12a. It is fixed integrally to both ends. The fixing member 12b is fixed to the wire 12a by using a friction welding machine to press the rotated steel plate against the fixed wire 12a to generate frictional heat at a predetermined pressure on the rotating steel plate. It can be easily performed by welding a steel plate to the wire 12a (friction welding A).
Here, the joining method of the wire 12a and the fixing member 12b is not limited to the friction welding A, and it is only necessary that integration such as gas welding or arc welding is possible. The “width” of the fixing member 12b is unified to be a diagonal length when the shape of the fixing member 12b is rectangular or polygonal, a diameter when circular, or a long side length when elliptical.

Needless to say, the configuration, shape, and the like of the fixing member 12b are not limited to those described above, and may be a circle, an ellipse, a polygon, or the like, and may be set as appropriate.
For example, as shown in FIG. 4 (a), a threaded reinforcing bar is used as the wire 12a, a lock nut is screwed into the tip, and a double nut is used to remove rattling between the wire 12a and the lock nut, As a fixing member 12b, the thickness of the fixing member 12b is 150% to 250% of the rebar diameter of the wire 12a, and the length is the rebar diameter of the wire 12a by any method of injecting a filler such as epoxy resin into the gap inside the nut. You may comprise so that it may become 100%-250%.

  Moreover, as shown in FIG.4 (b), it forms in the width | variety of 120%-130% of the reinforcing bar diameter of the wire 12a by hitting or pressing to the axial direction in the state which heated the tip of the wire 12a which is a reinforcing bar. The protruding portion may be used as the fixing member 12b.

  Moreover, as shown in FIG.4 (c), using metal materials which are comparatively easy to process, such as mild steel and aluminum alloy, thickness is 15 to 40% of the reinforcing bar diameter of the wire 12a, and length is the wire 12a. By preparing a cylindrical body having a shape of 100% to 250% of the diameter of the reinforcing bar, covering this with the tip of the wire 12a, and crushing the periphery from the periphery using a gripper in which two half rings are combined. Alternatively, the fixing member 12b may be configured by narrowing (squeezing) a cylindrical body used for a squeeze joint of a reinforcing bar and plastically deforming the cylindrical body so as to be integrated with the wire 12a.

  4D, a circular steel plate having a thickness of 30% to 80% of the reinforcing bar diameter of the wire 12a and a width of 140% to 200% of the reinforcing bar diameter of the wire 12a. You may manufacture by carrying out the friction welding A to the front-end | tip part of the wire 12a. Further, as shown in FIG. 4 (e), an ellipse having a thickness of 30% to 80% of the rebar diameter of the wire 12a and a width of 140% to 200% of the rebar diameter of the wire 12a (on the side of the oval or circle). The fixing member 12b may be configured by fixing a steel plate (including a shape in which the portion is cut off) to the tip of the wire 12a by friction welding A or the like.

The fixing members 12b and 12b formed at both ends of the shear reinforcing member 12 are not necessarily formed in the same shape as long as they can exhibit sufficient proof stress against the shearing force acting on the assumed side wall 20. There is no need to be done. That is, it may be set freely in accordance with factors such as the reinforcement state of the side wall 20 to be reinforced, concrete strength, wall thickness, and the like.
Further, according to the stress acting on the assumed side wall 20, the shear reinforcement composite capsule 10 in which the shear reinforcement composite capsule 10 is arranged or the shear reinforcement member 12 having a different shape and dimension is arranged depending on the position is arranged. May be.

Here, the composite capsule 10 for shear reinforcement according to the present embodiment is manufactured in advance in a factory or the like, and is manufactured in a state where a certain quality is ensured.
Moreover, in this embodiment, the shear reinforcement member 12 is arrange | positioned at the inner surface side of the side wall 20 in the state which has arrange | positioned the composite capsule 10 for shear reinforcement in the reinforcement member insertion hole 21, as shown in FIG. In other words, the fixing member 12 b on the inner surface side of the shear reinforcement member 12 is disposed on the inner surface side of the main reinforcing bar 22 on the inner surface side of the side wall 20, and the fixing member 12 b on the outer surface side of the shear reinforcement member 12 is disposed on the outer surface of the side wall 20. It is arranged on the inner surface side of the side distribution reinforcing bars. Needless to say, the arrangement of the shear reinforcement member 12 is not limited to the above-described one. For example, the fixing members 12b and 12b at both ends can each have a covering equivalent to that of the main reinforcing bar 22 of the side wall 20. You may arrange.

Next, a shear reinforcement method for the side wall 20 according to the present embodiment will be described with reference to the drawings.
The shear reinforcement method according to this embodiment is
(1) a drilling step of drilling the reinforcing member insertion hole 21 from one side of the side wall 20 toward the other side;
(2) an injection step of injecting the adhesive 30 into the reinforcing member insertion hole 21;
(3) An insertion step of inserting the composite capsule 10 for shear reinforcement into the reinforcing member insertion hole 21 from one side of the side wall 20.

<Punching process>
In the drilling process, the lateral spacing is set to the main reinforcing bars so that the main reinforcing bars and the reinforcing reinforcing bars are not damaged on the side walls 20 on the basis of the arrangement of the side walls 20 and the information of the nondestructive test. The vertical interval is the step of drilling the reinforcing member insertion hole 21 at the center of both reinforcing bars at the same interval as the distribution reinforcing bars.

  Drilling of the reinforcing member insertion hole 21 is performed in the direction from the inner surface side (one surface side) of the side wall 20 to the outer surface side (other surface side) and substantially perpendicular to the side wall W surface. Use a drilling means such as a drill to the depth of the position of the main reinforcing bar 22 on the outer surface side (see FIG. 5A). The reinforcing member insertion hole 21 is perforated with a slight downward inclination, and the hole diameter has a slight margin on the outer diameter of the composite capsule 10 for shear reinforcement, as shown in FIGS. 1 and 2 (b). It is formed to the expected value.

  Here, the reason why the reinforcing member insertion hole 21 is formed with a slight downward inclination is that the air inside the reinforcing member insertion hole 21 is injected when the adhesive 30 is injected and when the shear reinforcement composite capsule 10 is inserted. In this way, the adhesive 30 can be more completely filled. If the adhesive 30 can be completely filled, the reinforcing member insertion hole 21 does not necessarily have to be perforated with a slight downward slope.

  When the drilling of the reinforcing member insertion hole 10 is completed, the concrete powder generated along with the drilling accumulated in the hole is removed.

<Injection process>
In the injection step, as shown in FIG. 5B, the adhesive 30 for integrating the wall surface of the reinforcing member insertion hole 21 and the composite capsule 10 for shear reinforcement into the reinforcing member insertion hole 21 formed in the side wall 20. Is a step of injecting.

The injection of the adhesive 30 into the reinforcing member insertion hole 21 is performed by press-fitting the reinforcing member insertion hole 21 through an injection pipe (not shown) to the effect that air stays in the reinforcing member insertion hole 21. It shall be performed from (tip on the outer surface side). At this time, the amount of the adhesive 30 to be injected is such that the gap between the shear reinforcement composite capsule 10 and the reinforcement member insertion hole 21 adheres at least in a state in which the composite capsule 10 for shear reinforcement is disposed in the reinforcement member insertion hole 21. The amount is completely filled with the agent 30.

  In the present embodiment, a mortar epoxy adhesive is used as the adhesive 30, but the material constituting the adhesive 30 is a material that enables integration of concrete members. It is not limited and may be used by appropriately selecting from known adhesives. For example, an acrylic adhesive, a urethane adhesive, a polyester adhesive, or the like can be used.

<Insertion process>
As shown in FIG. 5C, the insertion step is a step of inserting the composite capsule 10 for shear reinforcement into the reinforcing member insertion hole 21 into which the adhesive 30 has been injected in the injection step before the adhesive 30 is cured. It is.

  The shear reinforcement composite capsule 10 is inserted into the reinforcement member insertion hole 21 by inserting the shear reinforcement composite capsule 10 while rotating the shear reinforcement composite capsule 10 in the circumferential direction (rotating around the central axis), so that the adhesive 30 is used for shear reinforcement. The entire gap between the composite capsule 10 and the reinforcing member insertion hole 21 is reached.

  The shear reinforcing composite capsule 10 is disposed in the reinforcing member insertion hole 21, whereby the shear reinforcing structure 1 is configured and the shear force acting on the side wall 20 is reinforced.

  In the construction of the shear reinforcement structure 1, the injection step and the insertion step are reversed, and the composite capsule 10 for shear reinforcement is inserted into the reinforcing member insertion hole 21, and then the adhesive 30 is combined with the composite capsule 10 for shear reinforcement. You may inject | pour into the clearance gap between the reinforcement member insertion holes 21. FIG. In this case, the adhesive 30 must be injected so that the gap is completely filled through a tube or the like.

  As mentioned above, according to the shear reinforcement structure 1 which concerns on this embodiment, in order to arrange | position the shear reinforcement member 12 in an appropriate position with respect to the existing reinforced concrete structure (side wall 20) with insufficient shear strength, shear strength Is improved, and bending toughness performance is imparted.

  Moreover, according to the shear reinforcement structure 1, an increase in shear strength and toughness performance can be realized efficiently. Moreover, since the shear reinforcement member 12 is directly embedded in the side wall 20 without increasing the concrete thickness of the existing reinforced concrete structure (side wall 20), the reinforcement is performed as in the conventional reinforced concrete thickening method. It is possible to prevent the inconvenience that the inner cross section is reduced later. In addition, since the main reinforcing bars 22 are not increased, the out-of-plane shear strength can be improved without increasing the bending strength. You can move to the destructive type.

  The shear reinforcement member 12 is arranged in such a manner that the shear reinforcement composite capsule 10 in which the shear reinforcement member 12 is disposed in advance is inserted into the reinforcement member insertion hole 21 formed in the side wall (existing reinforced concrete structure) 20. Since it completes only by inserting and integrating via an adhesive agent, it is performed simply and with high quality.

  The composite capsule 10 for shear reinforcement is manufactured with high quality in a state where the shear reinforcement member 12 is disposed in advance in a factory or the like, so that no construction error occurs and the shear reinforcement structure 1 is constant. It is possible to maintain the quality.

  In addition, regarding the integration of the shear reinforcement member 12 and the side wall 20, conventionally, filling of the filler and curing of the filler have hindered the shortening of the work period. However, according to the shear reinforcement method of the present invention, shearing is performed in advance. Since the shearing reinforcement member 12 is disposed inside the reinforcing composite capsule 10 and is simply inserted into the reinforcement member insertion hole 21 into which the adhesive 30 has been injected, the construction period can be greatly shortened. It is. Therefore, about the existing reinforced concrete structure in service, it becomes possible to shorten the period which stops service. Further, unlike the conventional case, the site is not soiled by handling the filler. In addition, the construction work can be saved and the construction period can be shortened, so that the cost can be reduced.

  Moreover, since the composite capsule 10 for shear reinforcement of the present invention has the groove 11a formed on the outer peripheral surface thereof, the gap between the adhesive 30 can be easily filled, and the groove 11a serves as a locking portion. Integration of the composite capsule 10 for shear reinforcement and the reinforcing member insertion hole 21 is made stronger.

  Further, the fixing members 12b and 12b provided at both ends of the wire 12a exhibit a sufficient fixing effect, and a tensile force acts on the wire 12 when an out-of-plane shearing force is generated. Since a supporting pressure acts between the fixing members 12b and a compressive stress field is formed in the hardened body 11 which is concrete between the fixing members 12b, the internal concrete itself is effective in increasing the shear resistance against shear. Shear reinforcement.

  Further, since the reinforcing member insertion hole 21 is blocked from the outside by the shear reinforcing composite capsule 10 and the adhesive 30, it can be expected to suppress deterioration from the viewpoint of durability after reinforcement.

  Further, by selecting the shape of the fixing member 12b on the inner surface side of the shear reinforcement member 12 according to the distribution of the bending moment generated at the time of the earthquake, it is economical by constructing a rational structure that exhibits toughness performance. It becomes possible to reinforce the configuration.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and it goes without saying that the above-described constituent elements can be appropriately changed in design without departing from the spirit of the present invention.
For example, the existing reinforced concrete structure to be reinforced may be a reinforced concrete structure, and there is no limitation on the type such as a cast-in-place reinforced concrete structure or a precast concrete structure. It can also be applied to materials and printing plates.
Further, the insertion interval, the number of insertions, the insertion position, and the like of the reinforcing member are not limited to the above-described embodiment, and can be determined as appropriate.

Needless to say, the shape of the fixing member formed on the shear reinforcement member is appropriately set according to the stress acting on the reinforced concrete structure to be reinforced.
In the above embodiment, the fixing members formed at both ends are the same. However, it goes without saying that the fixing members do not have to be the same.
Further, the shape and size of the fixing member is not limited to the above.

Further, the composition of the aggregate and the pozzolanic reactive particles constituting the cured body is not limited to those described in the above embodiment, and the aggregate has a maximum particle size of 3 mm or less, and the pozzolanic reactive particles are The particle diameter may be in the range of 0.01 to 15 μm.
Moreover, although it was set as the structure which mixes a silica fume with a cementitious mixed material, it is not necessary to mix a silica fume.

It is sectional drawing which shows the shear reinforcement structure which concerns on best embodiment. It is a figure which shows the composite capsule for shear reinforcement which concerns on best embodiment, Comprising: (a) is a perspective view, (b) is sectional drawing, (c) is a perspective view which shows the detail of a shear reinforcement member. (A)-(c) is a perspective view which shows the modification of the composite capsule for shear reinforcement. (A)-(g) is a perspective view which shows the modification of the fixing member of a shear reinforcement member. (A)-(d) is sectional drawing which shows each construction step of the shear reinforcement method which concerns on this embodiment. It is sectional drawing which shows the conventional shear reinforcement structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shear reinforcement structure 10 Composite capsule for shear reinforcement 11 Hardened body 11a Groove 12 Shear reinforcement member 12a Wire 12b Fixing member 20 Side wall (reinforced concrete structure)
21 Reinforcing member insertion hole 30 Adhesive G Jiyama

Claims (11)

An existing reinforced concrete structure, and a shear reinforcing composite capsule disposed inside a reinforcing member insertion hole formed in the reinforced concrete structure and fixed integrally therewith,
A shear reinforcement structure, wherein the composite capsule for shear reinforcement comprises a cured body of a cement-based mixed material formed in a columnar shape and a shear reinforcement member disposed inside the cured body. A shear reinforcement method for an existing reinforced concrete structure in which a shearing force acts,
Forming a reinforcing member insertion hole from one side of the existing reinforced concrete structure to the other side; and
Injecting an adhesive into the reinforcing member insertion hole;
Inserting the reinforcing member from one side of the existing reinforced concrete structure into a composite capsule for shear reinforcement consisting of a hardened body of cementitious mixed material formed in a columnar shape and a shearing reinforcing member disposed inside the hardened body And a step of inserting into the hole. In the step of inserting the composite capsule for shear reinforcement into the reinforcing member insertion hole,
The shear reinforcement method according to claim 2, wherein the composite capsule for shear reinforcement is inserted while being rotated in the circumferential direction.   A composite capsule for shear reinforcement, comprising: a hardened body of a cement-based mixed material formed in a columnar shape; and a shear reinforcing member disposed inside the hardened body.   The composite capsule for shear reinforcement according to claim 4, wherein a groove is formed on a surface of the cured body.   6. The composite capsule for shear reinforcement according to claim 4, wherein the cement-based mixed material is grout material or mortar.   6. The composite capsule for shear reinforcement according to claim 4, wherein the cement-based mixed material is a fiber-reinforced mixed material in which fibers are mixed in a cement-based matrix.   The said shear reinforcement member consists of a fixing member which is formed in the both ends of the said wire, and has a width dimension larger than the diameter of this wire, The said any one of Claim 4 thru | or 7 characterized by the above-mentioned. 2. A composite capsule for shear reinforcement according to item 1.   The composite capsule for shear reinforcement according to claim 8, wherein the fixing member is a plate-like member.   The composite capsule for shear reinforcement according to claim 8, wherein the fixing member is a nut. The wire consists of reinforcing bars,
The fixing member is a protrusion formed in a width of 120% to 130% with respect to the diameter of the wire by hitting or pressing in the axial direction in a state where the end of the wire is heated. The composite capsule for shear reinforcement according to claim 8.

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