JP7330071B2 - METHOD FOR REINFORCING REINFORCED CONCRETE STRUCTURES - Google Patents

Description

The present invention relates to a method for reinforcing reinforced concrete structures.

For example, in reinforced concrete structures that were designed according to the old seismic design method and are currently in service, when subjected to seismic force equivalent to level 2 seismic motion, etc. indicated in the current seismic design method, the shear strength and toughness of the members will be reduced. may be lacking. In particular, for underground structures in service, reinforcement work can only be performed from the inside of the structure, and it is difficult to actually perform shear reinforcement.
Therefore, for example, holes are drilled from the inside of existing underground reinforced concrete structures (box culverts, etc.) that can only be reinforced from the inside of the structure, and plastic grout, etc., is placed inside the holes. Post-installed plate-fixed shear reinforcing bars (PHb: Post-Head-bar, post-head bar, etc.) are pre-filled with filler material, and then plates, etc. are joined to both ends of steel bars such as deformed steel bars by friction welding. , post head bars are registered trademarks) are inserted and hardened to integrate the shear reinforcing bars and the reinforced concrete structure, improving the shear strength of the members and ensuring toughness during earthquakes. It is
In the above-mentioned reinforcement work, a hole is drilled sideways in the side wall of a reinforced concrete structure, a filler is filled, and a reinforcing bar is inserted sideways. After filling the hole with the filler, insert a reinforcing bar halfway through the hole (for example, the position where it hits the reinforcing bar inside the structure) and harden the filler. Filling the gap between the end of the reinforcing bar (insertion side end) and the wall surface of the structure (for example, the gap equivalent to the cover) with a filler that closes the cover of the hole without waiting for becomes possible.
On the other hand, in the so-called upward reinforcement work, in which a hole is drilled upward in the ceiling of a reinforced concrete structure, a filling material is filled, and a reinforcing bar is inserted upward, the reinforcing bar inserted upward into the hole falls. Since there is a fear, after inserting the reinforcing bar into the hole, a packer or the like is inserted into the hole to hold down the reinforcing bar from below. After inserting the packer, etc., it is necessary to wait for the filling material to harden. will be filled. Therefore, in the upward reinforcement construction, there is an inherent problem that construction time is required compared to the sideways reinforcement construction.

Here, in Patent Document 1, when a bar member such as a shear reinforcing bar is inserted upward into a hole opened upward in an existing reinforced concrete structure, the drop of the bar member is prevented. There has been proposed an upward fixation method for rod members that eliminates the need for preparation and construction of fall prevention jigs, etc., thereby shortening the construction period and reducing costs. Specifically, when a rod member is inserted upward into a drilled hole opened upward in a reinforced concrete structure, a plurality of needle members extending from the front end side to the rear end side are provided around the rod member. This is a fixing method in which a needle member around the rod member is bitten into the drilled surface by inserting the rod member upward into the drilled hole. Here, the needle members are provided around the front end portion and the rear end portion of the bar member, respectively, and three or more needle members are provided around the attachment to the bar member.

JP 2016-183501 A

In the upward fixing method of the bar member described in Patent Document 1, the needle member for fixing the reinforcing bar is present around the reinforcing bar and the fixing body. Therefore, when inserting the reinforcing bar, there is a possibility that a gap that is not filled with mortar may be generated around the needle member. In addition, in order to exert the shear reinforcement effect, it is essential to transmit the tensile force of the reinforcing bars and the bearing force of the anchorage to the concrete through the filling mortar. In addition, due to the presence of voids for the reasons described above, there is a possibility that the transmission of the tensile force and bearing force described above may be hindered.
Furthermore, the needle member for fixing the reinforcing bar has a shape extending from the front end side to the rear end side, and the needle member needs strength to support the reinforcing bar while hanging on the hole wall. Although it is desired to use a steel member as the needle member, if the steel needle member is arranged under the fixing body, the steel extending portion may erode the cover portion. Can lead to corrosion of rebar.

The present invention relates to a method of reinforcing an existing reinforced concrete structure in an upward direction. , aims to provide a method for reinforcing reinforced concrete structures.

In order to achieve the above object, one aspect of the method for reinforcing a reinforced concrete structure according to the present invention is
A method for reinforcing a reinforced concrete structure, comprising reinforcing the reinforced concrete structure by constructing reinforcing bars upward from the bottom surface of an existing reinforced concrete structure,
a drilling step of drilling a hole upward from the lower surface of the reinforced concrete structure;
a filling step of filling the hole with a filler;
The reinforcing reinforcing bar is inserted into the hole and its lower end is positioned in the middle of the hole, a plate-shaped elastic body is inserted into the hole and locked to the wall surface of the hole, and an insertion support step for supporting by the body.

According to this aspect, the reinforcing reinforcing bar is inserted into the hole, the lower end of the reinforcing bar is positioned in the middle of the drilled hole, the plate-shaped elastic body is inserted into the hole, and is engaged with the wall surface of the hole, and the reinforcing reinforcing bar is attached. Since there is no foreign matter between the reinforcing steel bar and the hole that hinders the transmission of the tensile force of the reinforcing steel bar, etc., it is possible to construct a reinforcing structure that is excellent in shear reinforcement effect. can.
Further, the member that supports the lower end of the reinforcing reinforcing bar is a plate-shaped elastic body, which is as thin as possible. Corrosion of the reinforcing steel via the elastic body can be suppressed.
Furthermore, by supporting the reinforcing reinforcing bars inserted into the holes with plate-like elastic bodies, a packer or the like is inserted to prevent the reinforcing reinforcing bars from falling, as in the conventional construction method, and after waiting for the filler to harden, for example, By removing the packer on the next day, it is possible to solve the problem that upward reinforcement construction takes more time than horizontal reinforcement construction. Therefore, upward reinforcement construction can be realized in as short a time as possible.

Here, the plate-like elastic body includes a metal plate spring, an elastic plate-like resin member, and the like. This plate-like elastic body may be arranged outside the covering of reinforcing bars on the lower surface side of the reinforced concrete structure, or may be arranged inside the covering. The filling process of filling a filler such as plastic grout may be pre-filling after the drilling process and before the insertion support process, or may be post-filling after the insertion support process. .
In the actual reinforcement method, when constructing ceilings such as underground culverts, etc., from the bottom to the top, scan the bottom surface of the reinforced concrete structure with a rebar detector such as an electromagnetic radar measurement device to determine the position of the existing rebar. After confirming the above, upward drilling is carried out at a position that does not interfere with the existing reinforcing bars.
Furthermore, in the hole, the area below the plate-shaped elastic body that is not filled with the filler (for example, the area in the hole corresponding to the cover of the existing reinforcing bar) is post-filled with the filler, The pores are completely closed by the filler.

Another aspect of the method for reinforcing a reinforced concrete structure according to the present invention is characterized in that the plate-shaped elastic body is positioned outside the cover of reinforcing bars on the lower surface side of the reinforced concrete structure.
According to this aspect, by positioning the plate-shaped elastic body outside the cover of the reinforcing bar on the lower surface side of the reinforced concrete structure, for example, corrosion of the reinforcing reinforcing bar via the metal plate-shaped elastic body can be suppressed. can be done. Here, "outside the cover of reinforcing bars" means that the plate-like elastic bodies do not exist inside the cover of the reinforcing bars, so in existing reinforced concrete structures, the plate-like elastic bodies are located inside the structure rather than the reinforcing bars on the bottom side. means that it exists in Therefore, regarding the above-described "positioning of the lower end of the reinforcing bar in the middle of the hole", the reinforcing bar should be positioned so that the plate-shaped elastic body existing at the lower end of the reinforcing bar is positioned outside the cover of the existing reinforcing bar. The lower edge will be positioned.

In another aspect of the method for reinforcing a reinforced concrete structure according to the present invention, the plate-like elastic body is made of metal,
In the inserting and supporting step, the plate-like elastic body is magnetically attracted to the tip of a rod-like jig having a magnet at the tip, and the plate-like elastic body is inserted into the hole via the rod-like jig. and
According to this aspect, the plate-shaped elastic body is inserted into the hole while being magnetically attracted by the magnet attached to the tip of the rod-shaped jig. can be inserted deep into the hole.

Another aspect of the method for reinforcing a reinforced concrete structure according to the present invention is characterized in that the elastic plate has one or more slits.
According to this aspect, since the plate-like elastic body has one or more slits, the plate-like elastic body receives dynamic frictional force in the direction opposite to the insertion direction from the hole wall in the process of being inserted into the hole. When the plate-like elastic body is about to be deformed in the out-of-plane direction in the direction opposite to the insertion due to force, the plate-like elastic body can be easily deformed in the in-plane direction first through the slit. In this way, the plate-like elastic body deforms in the in-plane direction first before it deforms in the out-of-plane direction, and the deformation in the out-of-plane direction is suppressed, so that the plate-like elastic body is deformed in the out-of-plane direction. Deformation in the opposite direction of insertion and entry into the cover of the existing reinforcing bars (erosion of the cover) can be suppressed.
Furthermore, since the plate-shaped elastic body has one or more slits, the air caught in the process of inserting the plate-shaped elastic body into the hole can escape to the outside of the hole through the slit. While removing the air trapped through the holes, for example, the pre-filled filler is allowed to leak through the slit to the lower surface side of the plate-shaped elastic body, so that the plate-shaped elastic body and the filling material are separated from each other. Remaining voids between materials are suppressed.
Here, the plate-shaped elastic body having one or more slits includes a form having an H shape in plan view (this form has two slits), a circular shape in plan view and extending in the radial direction. Alternatively, a form having a plurality of slits may be used.

In addition, one aspect of the reinforcing structure for a reinforced concrete structure according to the present invention is
A reinforcing structure for a reinforced concrete structure in which reinforcing bars are embedded upward from the bottom surface of an existing reinforced concrete structure,
a hole extending upward from the lower surface of the reinforced concrete structure;
the reinforcing reinforcing bars inserted into the holes;
a plate-like elastic body that abuts on the lower end of the reinforcing reinforcing bar and is locked to the wall surface of the hole;
and a filling material filled and hardened in the hole.

According to this aspect, the reinforcing reinforcing bar inserted into the upwardly extending hole is supported by the plate-shaped elastic body that is locked to the wall surface of the hole at the lower end thereof, and the filling material is placed in the hole. By being filled and hardened, there is no foreign matter between the reinforcing reinforcing bar and the hole that hinders the transmission of the tensile force of the reinforcing bar, resulting in a reinforcing structure with excellent shear reinforcing effect.
Further, the member that supports the lower end of the reinforcing reinforcing bar is a plate-shaped elastic body, which is as thin as possible. The reinforcement structure suppresses the corrosion of the reinforcing steel through the elastic body.
Also in the reinforcing structure of this aspect, as described above, if the plate-shaped elastic body is positioned outside the reinforcing bar covering on the lower surface side of the reinforced concrete structure, the plate-shaped elastic body is made of metal, for example. Corrosion of the reinforcing steel via the steel is further suppressed.
Further, if the plate-like elastic body has one or more slits, deformation of the plate-like elastic body toward the lower surface side of the structure, which is the out-of-plane direction, is suppressed, and the plate-like elastic body cuts through the existing reinforcing bars. A reinforcing structure is formed that does not erode the cover of the cover.

According to the method of reinforcing a reinforced concrete structure of the present invention, it relates to a method of reinforcing an existing reinforced concrete structure in an upward direction. Reinforcement construction can be realized in time.

1 is a perspective view of an example of a plate-like elastic body applied in a reinforcing method for a reinforced concrete structure according to an embodiment; FIG. FIG. 10 is a perspective view of another example of a plate-like elastic body; FIG. 4 is a perspective view showing a state in which a plate-like elastic body is magnetically attracted to a magnet at the tip of a rod-like jig, which is applied in the method for reinforcing a reinforced concrete structure according to the embodiment; It is process drawing of an example of the reinforcement method of the reinforced concrete structure which concerns on embodiment. FIG. 4 is a process chart illustrating an example of the reinforcing method for the reinforced concrete structure according to the embodiment, subsequent to FIG. 3 ; It is a figure explaining an example of the method of inserting a reinforcing bar in a hole. FIG. 4 is a process diagram illustrating an example of the reinforcing method for the reinforced concrete structure according to the embodiment, following FIG. 4 ; 7 is a view in the direction of arrow VII in FIG. 6; FIG. FIG. 7 is a process chart illustrating an example of the reinforcing method for the reinforced concrete structure according to the embodiment, subsequent to FIG. 6 ; FIG. 8 is a process diagram illustrating an example of the reinforcing method for the reinforced concrete structure according to the embodiment, following FIG. 8, and a vertical cross-sectional view of the example of the reinforcing structure for the reinforced concrete structure according to the embodiment.

Hereinafter, a reinforcing method and a reinforcing structure for a reinforced concrete structure according to embodiments will be described with reference to the accompanying drawings. In addition, in the present specification and drawings, substantially the same components may be denoted by the same reference numerals, thereby omitting duplicate descriptions.

[Embodiment]
<Plate-like elastic body>
First, with reference to FIGS. 1A and 1B, a plate-like elastic body that is applied in a reinforcing method for a reinforced concrete structure according to an embodiment and forms a reinforcing structure according to the embodiment will be described. Here, FIGS. 1A and 1B are perspective views of an example of a plate-like elastic body applied in the method of reinforcing a reinforced concrete structure according to the embodiment.

The plate-like elastic body 10 shown in FIG. 1A is substantially H-shaped in plan view and is formed of a metal plate spring or the like having a thin thickness (for example, about 0.5 mm to 1 mm). By forming two slits 12 in the elastic body 11, the two side pieces 11a are connected at their central positions by a connecting piece 11b.

In addition, the outer corners of each side piece 11a are chamfered to form curved portions 13, and the curved portions 13 provided at the corners allow the reinforced concrete structure to move upward from the bottom surface of the reinforced concrete structure. The plate-like elastic body 10 can be easily inserted into the circular cross-sectional hole to be drilled.

The dimensions of the plate-like elastic body 10 in a plan view are such that the plate-like elastic body 10 can be easily inserted into the hole, and the plate-like elastic body 10 is engaged with the wall surface of the hole in the middle of the hole so that the reinforcing bar 50 (Fig. 4, etc.) can be supported from below (a degree of locking can be formed). More specifically, since the deformation performance differs depending on the material (metal, resin) of the plate-like elastic body 10, etc., the relationship between the material of the plate-like elastic body 10 and the size of the hole, and furthermore, the above-mentioned hole. The planar dimensions of the plate-like elastic body 10 are set in consideration of the ease of insertion of the reinforcing steel bar 50 and the fact that it is locked in the hole while supporting the reinforcing steel bar 50 . In addition, the effect produced by the two slits 12 will be described in detail below.

On the other hand, the plate-like elastic body 10A shown in FIG. 1B is formed of a thin disk-shaped elastic body 14 made of metal, and has a single slit 15 in its radial direction in plan view. The dimension of the plate-like elastic body 10A in plan view is also set to be slightly larger than the hole, for example, based on its deformability and the cross-sectional dimension of the hole into which it is inserted. In addition to the plate-like elastic bodies 10 and 10A shown in FIGS. 1A and 1B, the plate-like elastic bodies to be applied may have various shapes such as an elliptical shape in plan view and a cross shape in plan view.

<Rod jig>
Next, with reference to FIG. 2, a rod-shaped jig that is applied in the method for reinforcing a reinforced concrete structure according to the embodiment will be described. Here, FIG. 2 is a perspective view showing a state in which a plate-like elastic body is magnetically attracted to a magnet at the tip of a rod-like jig, which is applied in the method for reinforcing a reinforced concrete structure according to the embodiment.

The rod-shaped jig 20 has a smaller cross-sectional dimension than a hole drilled upward from the bottom surface of the reinforced concrete structure, and has a magnet 21 at its tip. In the reinforcement work, a worker grips the rod-shaped jig 20 and magnetically attracts the metal plate-shaped elastic body 10 (or the plate-shaped elastic body 10A or the like) to the tip of the magnet 21 in the X direction. A plate-shaped elastic body 10 is inserted. Since the plate-like elastic body 10 is magnetically attracted to the magnet 21, the plate-like elastic body 10 falls downward when the plate-like elastic body 10 is inserted into the hole while receiving a dynamic friction force from the hole wall of the hole. is suppressed.

<Reinforcement method and reinforcement structure>
Next, with reference to FIGS. 3 to 9, an example of a reinforcing method and a reinforcing structure for a reinforced concrete structure according to the embodiment will be described. Here, FIGS. 3, 4, 6, 8, and 9 are process diagrams of an example of the reinforcing method for the reinforced concrete structure according to the embodiment, and FIG. 9 further shows the reinforced concrete structure according to the embodiment. is a longitudinal sectional view showing an example of the reinforcing structure of .

The illustrated reinforced concrete structure 30 to be reinforced is an existing structure in the ground with a natural ground G on its back surface 32, such as a box culvert that forms an underground passage, an underground utility tunnel, and the like. Then, it is a method of reinforcing the reinforced concrete structure 30 in which, for example, the ceiling of the reinforced concrete structure 30 is reinforced by constructing a reinforcing reinforcing bar upward from the lower surface 31 of the reinforced concrete structure 30 . Note that the reinforced concrete structure to which the method and structure for reinforcing a reinforced concrete structure according to the embodiment are applied is not limited to an underground box culvert or the like as shown in the illustrated example.

As shown in FIG. 3, when drilling, first, a worker (not shown) inside IN of the box culvert, which is a reinforced concrete structure 30, places a reinforcing bar probe 90 using electromagnetic waves or the like on the lower surface 31 of the ceiling. By scanning in the Y1 direction, the position of the reinforcing bar 40 on the bottom side of the ceiling is specified. In the ceiling of the box culvert 30 in the illustrated example, rebars 40 extending in mutually orthogonal X and Y directions forming the main reinforcing bars of the floor slab are arranged. It should be noted that the reinforcing bars 40 that form the floor slab and that intersect each other may be the main reinforcing bars that extend in either one of the X direction and the Y direction.

In the lower surface 31 where the reinforcing bars 40 are not present and specified by the scanning of the reinforcing bar probe 90, a worker uses a rock drill (not shown) such as a leg drill or a drifter to create a hole 35 with a predetermined diameter and a predetermined extension. (drilling process). In the illustrated example, a hole 35 having a length up to the vicinity of the reinforcing bar 45 on the ground side is drilled, and the cover of the reinforcing bar 40 on the lower side to the lower surface 31 is s.

Next, as shown in FIG. 4, an injection hose (not shown) is inserted from the opening 36 of the hole 35 to pre-fill a filler 60 such as plastic grout (filling step). Here, “pre-filling” means filling the hole 35 with the filler 60 before inserting the reinforcing bar 50 . Post-filling is applied in which the reinforcing reinforcing bar 50 is inserted into the hole 35 and the plate-like elastic body 10 or the like shown in FIG. You may Since the elastic plate 10 has the slits 12, such post-filling is also possible.

For example, in the hole 35 , the filling material 60 is pre-filled in a range slightly deeper than the reinforcing bar 40 on the lower surface side, and then the reinforcing reinforcing bar 50 is inserted into the hole 35 in the upward Y2 direction.

Here, the reinforcing bar 50 is a post-installed plate fixing type shear reinforcing bar in which steel plates 52 and 53 are joined to both ends of a steel bar 51 such as a deformed steel bar by friction welding. The length of the reinforcing bar 50 is, for example, such that the steel plate 53 at the tip abuts the tip of the hole 35 and the steel plate 52 at the rear end is positioned above the reinforcing bar 40 on the bottom side. More specifically, the steel plate 52 at the rear end is arranged in the middle of the hole 35 so that the plate-like elastic body 10 to be installed later does not invade the cover s. A steel plate 52 at the rear end is arranged at the same position as the upper reinforcing bar 40 among the mutually crossing reinforcing bars 40 on the side.

Further, the diameter of the steel plates 52 and 53 is set to be smaller than the diameter of the hole 35, so that when the reinforcing bar 50 is inserted into the hole 35 filled with the filler 60, the steel plate at the rear end The filling material 60 slightly leaks downward from the side of the steel plate 52, and the filling material 60 wraps around the unevenness between the steel bar 51 and the steel plates 52 and 53 without gaps, and the filling material 60 and the reinforcing bar 50 The reinforcing reinforcing bars 50 are embedded in the filler 60 in such a manner that there is no gap between them.

In inserting the reinforcing bar 50 into the hole 35, it is preferable to apply an air mixture prevention cover 80 as shown in FIG. The air mixture prevention cover 80 has a donut shape with an insertion hole 81 in the center, and has one half slit 82 communicating with the insertion hole 81. It is a member made of a resin material (for example, urethane) that is slightly deformed in the Y3 direction when it is unfolded, and then returns to its original shape.

When inserting the reinforcing bar 50 into the hole 35, the left and right sides of the half slit 82 of the air mixture prevention cover 80 are widened, the steel rod 51 of the reinforcing bar 50 is inserted into the insertion hole 35, and the left and right sides of the half slit 82 are inserted. Then, U-shaped connecting pins 84 are inserted into the pin holes 83 formed on the left and right side surfaces to fix the left and right half slits 82 of the air mixture prevention cover 80 .

Then, the worker inserts the reinforcing reinforcing bar 50 into the hole 35 in the Y2 direction while pressing the air mixture prevention cover 80 against the opening 36 from below. By inserting the reinforcing reinforcing bar 50 into the hole 35 while applying the air mixture prevention cover 80 in this way, it is possible to suppress introduction of air into the hole 35 (air entrainment) when the reinforcing reinforcing bar 50 is inserted. be able to.

Next, as shown in FIG. 6, the plate-shaped elastic body 10 is magnetically attracted to the magnet 21 at the tip of the rod-shaped jig 20, and the rod-shaped jig 20 is used to move upward toward the hole 35 through the opening 36. , the elastic plate 10 is inserted in the Y4 direction. At this time, since the plate-shaped elastic body 10 is inserted while being in sliding contact with the hole wall of the hole 35, it receives a dynamic frictional force Q from the hole wall in the direction opposite to the insertion direction during this insertion process. Due to this dynamic frictional force Q, the plate-like elastic body 10 tries to deform in the out-of-plane direction in the opposite direction of insertion.

However, since the plate-like elastic body 10 has two slits 12, as shown in FIG. It is easily deformed. In this manner, the plate-like elastic body 10 is deformed in the in-plane direction before being deformed in the out-of-plane direction, and the deformation in the out-of-plane direction is suppressed. deformation in the direction opposite to the insertion and entering the cover s of the reinforcing bar 40 on the lower surface side (eroding the cover s).

As shown in FIG. 8, the plate-shaped elastic body 10 abuts against the lower steel plate 52 and is locked to the hole wall of the hole 35 in such a manner as not to erode the cover s of the reinforcing bar 40 on the lower surface side. In the state where the plate-like elastic body 10 is engaged with the hole wall, the reinforcing reinforcing bar 50 is supported from below by the plate-like elastic body 10 (this is the insertion supporting step).

In this way, since the reinforcing bar 50 is supported from below by the elastic plate 10, a packer or the like is inserted into the hole as in the conventional construction method, and after the filler hardens, for example, the reinforcing bar is removed. It is no longer necessary to remove the packer on the day after insertion, and it is possible to perform upward reinforcement construction in a short construction time in the same way as lateral reinforcement construction.

Since the plate-like elastic body 10 has one or more slits 12 , the air caught in the process of inserting the plate-like elastic body 10 into the hole 35 flows out of the hole 35 through the slits 12 . can escape. Then, while the air entrained through the holes 35 is released, the pre-filled filler 60 is allowed to leak through the slits 12 to the lower surface of the plate-shaped elastic body 10, thereby forming a plate-shaped elastic body. A gap remaining between the elastic body 10 and the filler 60 is suppressed.

In FIG. 8, although the filling material 60 leaks slightly below the plate-like elastic body 10, the gap SP remains in the area of the cover s up to the opening 36. As shown in FIG. Therefore, as shown in FIG. 9, the gap SP is filled with a filler 65 made of the same material as the filler 60 to close the gap SP. Then, the reinforcing structure 70 is constructed by curing the fillers 60 and 65 .

In the reinforcing structure 70 , there is no gap between the reinforcing bar 50 and the filler 60 , and no foreign matter exists around the reinforcing bar 50 . The bearing force of the steel plates 52 and 53 can be effectively transmitted to the reinforced concrete structure 30, and the reinforcement structure has excellent shear reinforcement effect. In addition, in the reinforcing structure 70 , since the metal plate-like elastic bodies 10 that support the reinforcing reinforcing bars 50 from below do not erode the cover s of the existing reinforcing bars 40 , the reinforcing reinforcing bars 50 through the plate-like elastic bodies 10 do not erode. Corrosion is suppressed.

It should be noted that other embodiments may be possible in which other components are combined with the above-described configurations, etc., and the present invention is not limited to the configurations shown here. . Regarding this point, it is possible to change without departing from the gist of the present invention, and it can be determined appropriately according to the application form.

10, 10A: plate-like elastic body 11, 14: elastic body body 11a: side piece 11b connecting piece 12, 15: slit 20: rod-shaped jig 21: magnet 30: reinforced concrete structure (existing reinforced concrete structure, box culvert)
31: Lower surface 32: Back surface 35: Hole 36: Opening 40: Reinforcing bar (existing reinforcing bar, reinforcing bar on the lower side)
45: Reinforcing bars (existing reinforcing bars, reinforcing bars on the ground side)
50: Reinforcing bar (post-installed plate fixing type shear reinforcing bar)
51: Steel bar (deformed steel bar)
52, 53: steel plate 60: filler (plastic grout)
70: Reinforcement structure (reinforcement structure of reinforced concrete structure)
80: Air mixture prevention cover 81: Insertion hole 82: Half slit 83: Pin hole 84: Connecting pin 90: Reinforcement probe G: Ground IN: Inside of structure s: Cover

Claims (3)

A method for reinforcing a reinforced concrete structure, comprising reinforcing the reinforced concrete structure by constructing reinforcing bars upward from the bottom surface of an existing reinforced concrete structure,
a drilling step of drilling a hole upward from the lower surface of the reinforced concrete structure;
a filling step of filling the hole with a filler;
The reinforcing reinforcing bar is inserted into the hole and its lower end is positioned in the middle of the hole, a plate-shaped elastic body is inserted into the hole and locked to the wall surface of the hole, an insertion support step for supporting by the body ;
The plate-like elastic body is made of metal,
In the inserting and supporting step, the plate-like elastic body is magnetically attracted to the tip of a rod-like jig having a magnet at the tip, and the plate-like elastic body is inserted into the hole via the rod-like jig. A method for reinforcing a reinforced concrete structure. 2. The method of reinforcing a reinforced concrete structure according to claim 1, wherein said plate-like elastic body is positioned outside the covering of reinforcing bars on said lower surface side of said reinforced concrete structure. 3. The method of reinforcing a reinforced concrete structure according to claim 1 , wherein said elastic plate has one or more slits.

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