JP5192724B2 - Shear reinforcement method and filler filling method - Google Patents

Description

  The present invention relates to a method for shear reinforcement of an existing concrete structure in which a shearing force acts and a method for filling a hole in a drilled hole formed in an existing concrete structure.

  For example, as a seismic reinforcement method for an existing concrete structure, a shear reinforcement bar may be constructed by post-construction. In the construction of such a shear reinforcing bar, a reinforcing member insertion hole is drilled in a concrete structure, a shear reinforcing bar is disposed in the reinforcing member insertion hole and a filler is filled in the reinforcing member insertion hole. To do.

  In such a seismic reinforcement method, the filler filled in the reinforcing member insertion hole flows out from the hole of the reinforcing member insertion hole after filling, so that there is a gap between the filler and the hole wall of the reinforcing member insertion hole. There may be gaps. If there is a gap between the hole wall and the filler, this gap becomes a waterway, and there is a problem that groundwater or the like permeates into the structure.

Therefore, conventionally, the hole of the reinforcing member insertion hole is closed with a pressing plate or the like to prevent the filling material from sagging and prevent a gap from being formed between the filling material and the hole wall ( For example, see Patent Document 1).
JP 2004-293294 A (paragraph number [0042], FIG. 6)

However, even if the reinforcing member insertion hole is filled with the filler, the filler and the hole wall are not integrated, so that the groundwater or the like permeates from the back of the structure or cracks formed in the structure. In some cases, the joint surface between the filler and the hole wall becomes a waterway, and the groundwater may flow into the structure.
Such a problem has arisen not only in the shear reinforcement of the existing structure but also in the filling of the hole of any existing concrete structure, for example, the processing after the drilling of the core boring.

  The present invention has been made in order to solve the above-mentioned problems, and it is necessary to provide a post-construction stop for the shear reinforcement of the existing concrete structure and the filling of the hole formed in the existing concrete structure with the filler. It is an object of the present invention to provide a shear reinforcement method and a filling method of a filler that can be performed so that the aqueous state becomes excellent.

In order to solve the above-mentioned problems, the shear reinforcement method of the present invention sprays an aqueous solution containing an inorganic crystal growth agent on the inner wall surface of a bottomed hole formed in an existing concrete structure, and then A reinforcing member is inserted into the hole and the hole is filled with a filler.

According to this shear reinforcement method, the inner wall surface of the hole is sprayed with an aqueous solution containing an inorganic crystal growth agent, and a cement crystal is propagated on the inner wall surface. In addition, moisture that has penetrated from the back surface or cracks of the concrete structure is prevented from penetrating into the hole. In addition, since the aqueous solution containing the inorganic crystal growth agent is adhered to the entire inner wall surface of the holed hole by spraying, the water stopping performance is ensured by a simple operation.
Furthermore, it is preferable that the reinforcing member is disposed in the existing concrete structure, so that the shear strength of the concrete structure can be improved.

Further, the shear reinforcement method, a pressing member for preventing the outflow of filled in the drilling hole hole hole of the drilling hole the filler is disposed, the said pressing member is fixed by the pressing spring.

Such a shear reinforcement method is preferable because it prevents the filler from flowing out from the hole opening and prevents a gap from being formed between the filler and the hole.
In addition, it is preferable to use the presser spring because the presser member can be easily fixed.

Also, the filling method of the filler according to the present invention comprises spraying an aqueous solution containing an inorganic crystal growth agent on the inner wall surface of a bottomed hole formed in an existing concrete structure, and then filling the hole with the filler. And a pressing member that prevents the filler filled in the hole from flowing out is disposed at the hole of the hole, and the pressing member is fixed by a pressing spring .

  According to the shear reinforcement method of the present invention, it is possible to perform shear reinforcement of an existing concrete structure in a state in which water blocking is ensured. In addition, according to the filling method of the filler of the present invention, for an existing concrete structure in which a hole is formed, filling of the hole into the hole is ensured by a simple method to ensure water-stopping after construction. It was possible to do as much as possible.

  A preferred embodiment of the reinforcing method of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted.

  The shear reinforcement method according to the present invention includes a drilling step of drilling a reinforcing member insertion hole (drilling hole) in an existing concrete structure, and spraying an aqueous solution containing an inorganic crystal growth agent on the inner wall surface of the reinforcing member insertion hole. The spraying step and a filling step of inserting a shear reinforcing member (reinforcing member) into the reinforcing member insertion hole sprayed with the aqueous solution and filling the filler are included.

(1) Drilling step As shown in FIG. 1 (a), the drilling step is a shear reinforcement member from the inner side (opposite side of the ground G) to the outer side (ground G side) of the side wall W of the existing reinforced concrete structure. This is a step of performing an operation of forming a reinforcing member insertion hole (hole drilling hole) 10 for installing 20 (see FIG. 2A).

  The reinforcing member insertion hole 10 may damage the main reinforcing bar R1 and the distributed reinforcing bar R2 during drilling based on the arrangement of the existing reinforced concrete structure (side wall W) and information on the nondestructive test. In order not to be present, the horizontal interval is arranged at the center of both the reinforcing bars R1 and the vertical interval is the same as that of the distribution reinforcing bar R2. The reinforcing member insertion hole 10 is drilled in the direction from the inside of the side wall W to the outside in contact with the ground G and in the direction substantially perpendicular to the surface of the side wall W, such as an impact drill, a rotary hammer drill, a core drill, etc. The perforating means 60 is used. The reinforcing member insertion hole 10 is provided in a length dimension obtained by subtracting the thickness of the covering concrete having a predetermined dimension on the ground G side, and the hole diameter is formed at the distal end portion of the shear reinforcing member 20 shown in FIG. The diameter (width dimension) of the front end fixing member 22 is assumed to have a slight allowance.

Thereafter, the drilling means 60 is used to widen the drilling diameter inside the side wall W so that the peripheral edge portion of the proximal fixing member 23 attached to the proximal end portion (terminal portion) of the shear reinforcement member 20 is hooked. And the widened portion 11 is formed. The drilling depth of the widened portion 11 is a value obtained by adding a predetermined covering concrete thickness (in this embodiment, the covering concrete thickness equivalent to the main reinforcement R1) to the thickness of the proximal fixing member 23.
Then, when the perforation of the widened portion 11 of the reinforcing member insertion hole 10 is completed, the concrete powder generated for the perforation in the reinforcing member insertion hole 10 is removed.

(2) Spraying step The spraying step is a step of spraying the impregnating agent 40 made of an aqueous solution containing an inorganic crystal growth agent on the inner wall surface of the reinforcing member insertion hole 10 as shown in FIG.
The spraying of the impregnating agent 40 is performed by using the sprayer 41, and the reinforcing member until the tip of the nozzle 42 of the sprayer 41 is positioned in the vicinity of the bottom (the end of the ground G side) of the reinforcing member insertion hole 10. After being inserted into the insertion hole 10, the impregnating agent 40 is sprayed while being pulled out from the tip of the nozzle 42, so that the entire inner wall surface of the reinforcing member insertion hole 10 is formed.
In addition, what is necessary is just to use a well-known thing for the sprayer 41 suitably, The form etc. are not limited.

The impregnating agent 40 is sprayed on the inner wall surface of the reinforcing member insertion hole 10 to repeatedly perform a crystallization reaction on the concrete surface of the inner wall surface, thereby filling a deficient portion such as a capillary space of the concrete with cement crystals. Promote densification of concrete surface. By promoting the densification by the impregnating agent 40 on the surface of the reinforcing member insertion hole 10, the water stoppage of the inner wall surface of the reinforcing member insertion hole 10 is improved.
The impregnating agent 40 made of an aqueous solution containing an inorganic crystal growth agent is not limited as long as it is an aqueous material and can be sprayed, and is appropriately selected from known materials and used. That's fine.

(3) Filling step In the filling step, the shear reinforcing member 20 is inserted into the reinforcing member insertion hole 10 shown in FIG. 1C and FIGS. This is a process of filling the filler 30 and performing an integration operation.

In the filling step, as shown in FIG. 1C, first, the filler 30 is filled into the general portion 12 other than the widened portion 11 of the reinforcing member insertion hole 10.
Filling the general portion 12 with the filler 30 is performed before the growth of cement crystals by the impregnating agent 40 starts. In the present embodiment, the press-fitting machine M is used to press-fit the filler 30 made of grout or the like into the reinforcing member insertion hole 10. The filling time of the filling material 30 into the general part 12 is not limited to the above-mentioned time. For example, immediately after the start of growth of cement crystals by the impregnating agent 40, the progressing stage, or the growth It may be after making it.

  Filling the general portion 12 with the filler 30 is performed by press-fitting the filler 30 from the tip of the nozzle M1 with the nozzle M1 of the press-fitting machine M inserted to the bottom of the reinforcing member insertion hole 10 (tip on the ground G side). The nozzle M1 is pulled out from the tip of the reinforcing member insertion hole 10 while being pulled out. The filling amount of the filler 30 is desirably set to such an extent that the general portion 12 is filled in a state where a shear reinforcement member 20 described later is inserted into the reinforcement member insertion hole 10.

  Here, the grout as the filler 30 is a material composed of cement, a pozzolanic substance such as silica fume and quartz powder, a thickener, and water, and has a property that does not flow down even when filled upward. Therefore, it is possible to fill without being limited to the direction of the reinforcing member insertion hole 10. In addition, the material etc. of the filler 30 are not limited, What is necessary is just to select and use from a well-known material suitably.

  Next, as shown in FIG. 2A, the shear reinforcing member 20 is installed in the reinforcing member insertion hole 10 and integrated with the side wall W.

  The shear reinforcement member 20 includes a shear reinforcement bar 21, and a distal end fixing member 22 and a proximal end fixing member 23 which are provided at the distal end portion and the proximal end portion of the shear reinforcement reinforcement rod 21 and have a larger cross-sectional shape than the shear reinforcement reinforcing bar 21. And is composed of.

The shear reinforcement member 20 is inserted into the reinforcement member insertion hole 10 so that the tip fixing member 22 is positioned on the ground G side. When the shear reinforcement member 20 is disposed in the reinforcement member insertion hole 10, the proximal end fixing member 23 is locked to the widened portion 11.
In the present embodiment, in the state where the shear reinforcement member 20 is inserted into the reinforcement member insertion hole 10, each of the distal end fixing member 22 and the proximal end fixing member 23 has a concrete covering thickness equivalent to that of the main reinforcing bar R1. .

  In the present embodiment, steel plates are used as the distal end fixing member 22 and the proximal end fixing member 23, and the steel is rotated to the distal end and the proximal end of the fixed shear reinforcing bar 21 using a friction welding machine. By pressing the steel plate (the front end fixing member 22 and the base end fixing member 23), friction heat is generated at a predetermined pressure on the rotating steel plate, and the front end fixing member 22 and the base end fixing member 23 are shear-reinforced. The shear reinforcement member 20 is formed by welding to 21. The distal end fixing member 22 and the proximal end fixing member 23 have a thickness of 40% to 80% of the diameter of the shear reinforcing bar 21 and a width (diameter) of 150% to 300% of the diameter of the shear reinforcing bar 21. Steel plates can be used. Further, the shapes of the distal end reinforcing member 22 and the proximal end fixing member 23 are not limited, and can be set as appropriate, for example, a circle, an ellipse, an oval, a square, a rectangle, and other polygons. .

In addition, the material and shape which comprise the front-end | tip fixing member 22 and the arrival end fixing member 23 are not limited, It is possible to set suitably.
For example, as the front end fixing member 22 or the base end fixing member 23, a cylindrical body made of a metal material that is relatively easy to process such as mild steel or aluminum alloy may be used. In this case, the cylindrical body is placed on the distal end or the base end of the shear reinforcing reinforcing bar 21, and the periphery is crushed from the periphery using a gripper in which two half rings are combined, or the squeeze joint of the reinforcing bar is used. By narrowing (squeezing) the cylindrical body to be used, the shear reinforcing member 20 can be easily manufactured by plastically deforming the cylindrical body and integrating it with the shear reinforcing reinforcing bar 21. As such a cylindrical body, for example, the wall thickness (member thickness in the reinforcing bar radial direction of the shear reinforcing bar 21) is 15% to 40% of the diameter of the shear reinforcing bar 21 and the length (in the axial direction of the shear reinforcing bar 21). A material having a height of 100% to 250% of the diameter of the shear reinforcing steel bar 21 can be suitably used.

  In addition, a screw rebar is used as the shear reinforcement bar 21 and a lock nut is screwed into the tip, and a double nut is used to remove rattling between the shear reinforcement bar 21 and the lock nut, or an epoxy resin is provided in the gap inside the nut. As a distal end fixing member 22 or a proximal end fixing member 23, the width (width or diameter in the reinforcing bar radial direction of the shear reinforcing bar 21) is 150 of the diameter of the shear reinforcing bar 21. It can also be manufactured so that the length (thickness in the axial direction of the shear reinforcing bar 21) is 100% to 250% of the diameter of the shear reinforcing bar.

  Here, the combination of the distal end fixing member 22 and the proximal end fixing member 23 at both ends can be freely selected in accordance with factors such as the reinforcing state of the side wall W to be reinforced, concrete strength, and wall thickness.

As shown in FIG. 2 (b), after inserting the shear reinforcement member 20 into the reinforcement member insertion hole 10, in order to prevent the filler 30 filled in the reinforcement member insertion hole 10 from flowing out, The pressing member 50 is disposed in the widened portion 11 of the reinforcing member insertion hole 10.
The presser plate 50 is disposed in contact with the end face of the base end fixing member 23 and is fixed by being pressed from the inside toward the ground G side by a presser spring 51.

  As shown in FIGS. 3A and 3B, the presser plate 50 is disposed in contact with the inner end face of the base end fixing member 23, and is approximately the same as the inner diameter of the widened portion 11. It is comprised by the circular board | plate material which consists of diameters. The material constituting the presser plate 50 is not limited, and may be appropriately selected from known materials such as steel and wood.

The presser spring 51 is a steel leaf spring and is longer than the diameter of the widened portion. In the present embodiment, as shown in FIG. 3C, a substantially H shape is shown in plan view, but the shape of the presser spring 51 is not limited.
As shown in FIG. 3A, the presser spring 51 is arranged in the widened portion 11 in a state of being curved so as to be convex toward the presser plate 50, and in a state where the center portion is in contact with the presser plate 50. Both ends are locked to the inner wall surface of the widened portion 11.

  In the present embodiment, the presser plate 50 and the presser spring 51 are configured as separate members, but the presser plate 50 and the presser spring 51 may be configured integrally in advance.

  After the shear reinforcement member 20 is inserted, the filler 30 is cured, and when the filler 30 is solidified and develops sufficient strength, the presser plate 50 and the presser spring 51 are removed, and the inner width of the proximal fixing member 23 is widened. The space 11a formed in the portion 11 is filled by rubbing the filler 31 made of a grout material with a trowel. In the present embodiment, after the filling of the filler 31 into the space 11a is completed, the inner surface of the side wall W so as to close the widened portion 11 so as to prevent the filler 31 from being deformed by its fluidity. Install in. The mold 32 may be installed as necessary. For example, when there is no possibility that the filler 31 is deformed, such as when the reinforcing member insertion hole 10 faces downward, the mold 32 is installed. There is no need. The material, shape, and installation method of the mold 32 are not limited as long as the filler 31 can be prevented from flowing out of the widened portion 11. Moreover, the material etc. which comprise the filler 31 with which the space 11a is filled are not limited, It is possible to use a well-known material suitably.

As shown in FIG. 4, the side wall W reinforced by the reinforcing method of the present invention is directly reinforced by the shear reinforcing member 20 against the oblique crack c generated when the out-of-plane shearing force S is applied, and sheared. It improves proof stress.
That is, when an out-of-plane shearing force S acts on the side wall W, an oblique crack c tends to occur. However, since a tensile force acts on the shear reinforcement member 20, the distal end fixing member 22 and the proximal end fixing member 23 at both ends are affected. A pulling force ft is applied. For this reason, in the concrete (hereinafter referred to as “inner concrete”) inside the distal end fixing member 22 and the proximal end fixing member 23, a supporting pressure acts on the inner concrete as a reaction force, and a field of the compressive stress fc is generated. It is formed. That is, the inner concrete is subjected to lateral restraint, resulting in an increase in resistance to oblique tension. For this reason, the shear reinforcement member 20 having the distal end fixing member 22 and the proximal end fixing member 23 at the ends increases the out-of-plane shear strength of the side wall W, and a compressive stress fc is generated in the internal concrete (compressive stress). As a result, the toughness performance is increased.

  As described above, according to the shear reinforcement method of the present invention, the shear strength and toughness performance can be obtained by directly embedding the shear reinforcement member 20 in the sidewall W without increasing the concrete thickness of the existing sidewall W. Therefore, it is possible to prevent the inconvenience that the inner air cross section decreases after reinforcement, as in the conventional reinforced concrete thickening method. In addition, since the main reinforcing bars are not increased, the out-of-plane shear strength can be improved without increasing the bending strength, so bending of reinforced concrete structures with the possibility of bending / shear pre-breaking type is possible. It is possible to move to the predestructive type.

  Further, since the impregnating agent 40 is sprayed on the inner wall surface of the reinforcing member insertion hole 10 and cement crystallization is performed by the impregnating agent 40, the water blocking property of the inner wall surface of the reinforcing member insertion hole 10 is excellent. In addition, groundwater or the like that has penetrated from the back surface of the side wall W or cracks does not flow into the reinforcing member insertion hole 10. Therefore, the joint surface between the reinforcing member insertion hole 10 and the filler 30 becomes a waterway, so that groundwater or the like does not enter the structure.

  Further, since the water stoppage of the reinforcing member insertion hole 10 is completed by simply spraying the impregnating agent 30 after the cutting of the reinforcing member insertion hole 10, the work is completed in comparison with the work process in the conventional shear reinforcement method. There is no significant impact on sex.

The proximal fixing member 23 provided at the proximal end of the shear reinforcing bar 21 and the distal fixing member 22 provided at the distal end can obtain a sufficient fixing effect and generate an out-of-plane shear force. Since a tensile force acts on the shear reinforcing reinforcing bar 21, a support pressure acts on the proximal end fixing member 23 or the distal end fixing member 22 and the proximal end fixing member 23, and a compressive stress field is formed in the internal concrete. On the other hand, the shear resistance of the inner concrete itself is increased, resulting in effective shear reinforcement.
Furthermore, since the reinforcing member insertion hole 10 is blocked from the outside by the filler 30, it can be expected to suppress deterioration from the viewpoint of durability after reinforcement.

Further, since the reinforcing member insertion hole 10 is prevented from flowing out of the filler 30 by the presser plate 50 in the widened portion 11, there is a gap between the filler 30 and the inner wall surface of the reinforcing member insertion hole 10. It is never formed. Therefore, the water stop performance of the reinforcing member insertion hole 10 is maintained.
Further, since the presser plate 50 is fixed by the presser spring 51, the presser plate 50 can be easily installed and removed.

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.
In particular, the existing concrete structure that is the object of the reinforcing method of the present invention is not limited, and can be applied to any concrete structure.

  In addition, the existing concrete structure to be reinforced may be a reinforced concrete structure, and there is no limitation on the type of the cast-in-place reinforced concrete structure, the precast concrete structure, etc. It can also be applied to ceiling slabs and bottom plates.

In the embodiment, the filler is inserted into the reinforcing member insertion hole and then the shear reinforcing member is inserted into the reinforcing member insertion hole. However, the filler is inserted into the reinforcing member after the shear reinforcing member is inserted. Needless to say, the holes may be filled.
Further, the insertion interval and the number of insertions of the shear reinforcement member are not limited to the above embodiment, and can be determined as appropriate.

The distal end fixing member and the proximal end fixing member of the shear reinforcement member may be formed as necessary and may be omitted.
Similarly, the widened portion of the reinforcing member insertion hole may be formed as necessary and can be omitted.

  Further, in the above-described embodiment, the shear reinforcement method for the reinforced concrete structure has been described. For example, the filling method of the filler according to the present invention is used in the restoration work of the concrete structure in which the drilling holes such as core boring are formed. May be. Thereby, the joint surface of a drilling hole and a filler does not become a water channel, and the concrete structure excellent in water stop is provided.

(A)-(c) is sectional drawing which shows each process of the shear reinforcement method concerning suitable embodiment of this invention. (A)-(c) is sectional drawing which shows each other process of the shear reinforcement method concerning suitable embodiment of this invention. It is a figure which shows the press plate concerning suitable embodiment of this invention, Comprising: (a) is a perspective view which shows the attachment condition of a press plate, (b), (c) is a perspective view of a press plate and a press spring. . It is a sectional side view which shows the stress state at the time of a shear force acting on the side wall which applied the shear reinforcement method concerning suitable embodiment of this invention.

Explanation of symbols

10 Reinforcing member insertion hole 11 Widened portion 20 Shear reinforcing member (reinforcing member)
30 Filling material 40 Impregnating agent (aqueous solution containing inorganic crystal growth agent)
50 Presser plate (presser member)
51 Presser spring G Ground W Side wall

Claims (4)

After spraying an aqueous solution containing an inorganic crystal growth agent on the inner wall surface of a bottomed hole formed in an existing concrete structure, a reinforcing member is inserted into the hole and the filler is filled in the hole. A shear reinforcement method,
A pressing member for preventing outflow of the filler filled in the hole is disposed at the hole of the hole .
A shear reinforcement method, wherein the pressing member is fixed by a pressing spring. The pressing member is disposed in contact with the end surface of the reinforcing member,
  The shear reinforcement method according to claim 1, wherein the pressing member and the presser spring are removed after the filler is cured. After spraying an aqueous solution containing an inorganic crystal growth agent on the inner wall surface of a bottomed hole formed in an existing concrete structure, the hole is filled with a filler, and the hole is filled with the filler. A filling material filling method, comprising: a pressing member that prevents the filling material filled in the hole hole from flowing out, and the pressing member is fixed by a pressing spring .   The filling material filling method according to claim 3, wherein the pressing member and the presser spring are removed after curing the filling material.

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