JP2012225090A - Anchor and method of fixing anchor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anchor which firmly fixes an additional member such as a steel bracket to an existing concrete member by less number of the anchors.SOLUTION: A steel pipe 11 is inserted into a hole 3b cut to a predetermined depth in an existing concrete member 3 from a surface 3a of the concrete member and is fixed by filling a space between an inner peripheral surface of the hole 3b and the steel pipe 11 with a filler 16. A small diameter hole 3c, of which inner diameter is smaller than the hole, is provided to a position much deeper than a bottom of the hole and an anchor bolt 12 is inserted thereinto to fix tightly. A nut 14 is screwed with a male screw part formed at a rear end of the anchor bolt so as to restrain to prevent the steel pipe from coming off from the concrete member via a bearing plate 13. The inside of the steel pipe is filled with a filler 18 to be cured. A male screw is formed on an outer peripheral surface of the steel pipe. A second nut 15 is screwed with the male screw, and a contact plate 2a of a steel bracket, which is an additional member, is sandwiched between the seconde nut and the concrete member to fix.

Description

  The present invention relates to an anchor for fixing an additional member made of steel or the like to an existing concrete member or concrete structure.

For concrete members or concrete structures, it may be necessary to fix an additional member such as a steel bracket after the concrete has hardened. For example, as described in Patent Document 1, a steel bracket is attached to a concrete bridge pier and a bridge girder, and these are connected to form a falling bridge prevention device. Moreover, a steel bridge is attached to the top of the bridge pier, and even if the bridge girder is largely displaced with respect to the pier, a falling bridge prevention device that supports the bridge girder with the steel bracket may be employed.
When repairing or expanding a concrete structure, as described in Patent Document 2, a steel bracket is attached to an existing concrete member in order to support a work scaffold or a support, and a work scaffold or a new one is attached to the steel bracket. In some cases, the weight of the concrete to be placed is temporarily supported.
On the other hand, when it is necessary to reinforce the concrete member, as described in Patent Document 3, brackets are attached to a plurality of positions of the concrete member, and tension members are stretched between them to form the concrete member. Additional prestress may be introduced. In addition to this, a member that is directly added to an existing concrete member is widely fixed by an anchor.

  Such an additional member such as a bracket is generally fixed using an anchor 100 as shown in FIG. In this structure, a contact plate 103 is provided on an additional member to be fixed to the concrete member 110, and the contact plate 103 is brought into contact with the surface of the concrete member 110. The contact plate 103 is provided with a through hole, and an anchor bolt 101 embedded in the concrete member 110 is inserted into the through hole. Then, the abutting plate 103 of the steel bracket 102 is fastened with a nut 104 twisted together with the anchor bolt 101 and fixed to the concrete member 100.

JP 2011-38392 A JP 2009-62768 A JP-A-10-183755

However, in the conventional structure in which the steel bracket 102 and the additional member are fixed by the anchor bolt 101, there is a problem that the following solution is desired.
When a load acts on the steel bracket 102 or the additional member and a large force acts along the surface of the concrete member 110 on which the steel bracket 102 or the like is attached, this force is transmitted to the concrete member 110 via the anchor bolt 101, A large shearing force acts on the anchor bolt 101. In order to resist this shearing force, the number of anchor bolts 101 must be increased or the diameter of the anchor bolts must be increased. When the number of the anchor bolts 101 increases, it is necessary to cut many holes for embedding the anchor bolts 101, which is not desirable in order to maintain the durability and the like of the existing concrete member 110. Further, when the diameter of the anchor bolt 101 is increased, the diameter of the hole to be cut in the concrete member 110 must be increased, and it is difficult to drill the hole so as not to cut the reinforcing bar 105.
On the other hand, when a large shearing force acts on the anchor bolt 101, a large supporting pressure acts on the contact surface 106 between the anchor bolt 101 and the concrete on the back side in the direction in which the shearing force acts. In order to reduce the bearing pressure, it may be necessary to increase the number of anchor bolts 101 or to increase the diameter.

  This invention is made | formed in view of such a situation, The objective is to provide the anchor which firmly adheres additional members, such as a bracket, to the existing concrete member with few numbers.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes a steel pipe inserted into a hole cut from the surface of an existing concrete member to a predetermined depth in the concrete member, and the hole from the bottom of the hole. An anchor bolt inserted into the steel pipe and inserted into a small-diameter hole cut into a deeper position with a smaller inner diameter or penetrated through the concrete member, and fixed so as not to come out; and the anchor bolt A nut that is screwed into an external thread formed at an end projecting from the concrete member, and restrains the steel pipe so as not to come out of the concrete member, and includes an outer peripheral surface of the steel pipe and the inside of the hole. An anchor that is filled with a filler and hardened is provided between the peripheral surface and the inside of the steel pipe.

In the above-mentioned anchor, a support plate having a through hole through which an anchor bolt is inserted is brought into contact with the rear end of the steel pipe inserted into the hole from the tip, and the nut restrains the steel pipe from coming out through this support plate. It is desirable to do. Further, the support plate that is in contact with the end face of the steel pipe may be a member that is separable from the steel pipe, or may be one that is in contact with the rear end face and integrally joined. Further, the bearing plate may constitute a part of an additional member such as a bracket fixed to the concrete member by the anchor.
The steel pipe may have such a length that the rear end protrudes from the surface of the concrete member when inserted into the hole from the front end, and is joined integrally with the support plate as described above. In this case, the steel pipe may be shorter than the depth of the hole.
Further, the filling material filled between the outer peripheral surface of the steel pipe and the inner peripheral surface of the hole and the filling material filled inside the steel pipe may be different in filling timing. However, it may be filled continuously on both sides. Different types of fillers can be used at different times.

  In the above-mentioned anchor, the anchor bolt deeply embedded in the concrete member resists pulling and restrains the steel pipe from being pulled out from the concrete member. And the steel pipe, the anchor bolt, and the filler filled and hardened between them are integrally resisted against the force in the direction along the surface of the concrete member. Therefore, it has a large shear resistance and the number of anchors for supporting the additional member is reduced. Moreover, even if the diameter of the anchor bolt deeply embedded in the concrete member is reduced, the outer diameter of the steel pipe can be increased to suppress the supporting pressure acting on the concrete member.

  The invention according to claim 2 is the anchor according to claim 1, wherein a male screw is formed on the outer peripheral surface of the steel pipe, and the second nut is screwed to the male screw, and is supported by the concrete member. The steel pipe is inserted into a through hole provided in the member, the additional member is sandwiched between the second nut and the concrete member, and the second nut is tightened to support the additional member. .

  In this anchor, the steel pipe can be fixed so as to protrude from the concrete member, and then the additional member can be fixed by inserting the steel pipe into a through hole provided in the additional member. Therefore, the step of fixing the steel pipe to the concrete and the step of fixing the additional member to the concrete member can be performed separately and reliably.

  The invention according to claim 3 is the anchor according to claim 1, wherein a steel plate abutting on the surface of the concrete member is fixed to a rear end of the steel pipe having a tip inserted into the hole. A plate constitutes a part of the additional member, and the steel plate is pressed against the concrete member side by tightening a nut screwed to the anchor bolt.

  In this anchor, the steel pipe and the additional member fixed to the steel pipe can be integrally fixed to the concrete member, and an efficient work can be performed.

  The invention according to claim 4 includes a step of cutting a hole from a surface of an existing concrete member at a depth reaching a reinforcing bar embedded in the concrete member, and a small-diameter hole having an inner diameter smaller than the hole, Cutting to a predetermined depth or through the concrete member, and inserting an anchor bolt into the small-diameter hole and fixing the anchor bolt so as not to come out by a filler, or anchoring to the small-diameter hole A step of engaging the bolt with a concrete member so as to prevent the anchor bolt from coming out, and inserting a steel pipe into the hole and forming at the rear end of the anchor bolt protruding from the concrete member The nut to be screwed into the male threaded portion is tightened in a state of being locked to the steel pipe, and the steel pipe is pushed toward the concrete member side. And fixing the steel pipe to the concrete member by curing the filler filled between the outer peripheral surface of the steel pipe and the inner peripheral surface of the hole; and filling the filler inside the steel pipe; , An anchor fixing method including:

In this method, it is possible to confirm the position of the reinforcing bar embedded near the surface of the concrete member by drilling a hole having a large inner diameter at a depth reaching the reinforcing bar. A small-diameter hole can be formed from the bottom of the hole to a position deeper than the reinforcing bar while avoiding the position of the reinforcing bar, and a hole for an anchor bolt can be provided without damaging the reinforcing bar. Then, by restraining the steel pipe inserted shallowly with an anchor bolt fixed in the small diameter hole so as not to come out, an anchor having a large outer shape and a large shear resistance is formed near the surface of the concrete member.
In the above invention, the hole to be cut at a depth reaching the reinforcing bar embedded in the concrete member may be formed at a depth at which the surface of the reinforcing bar is exposed at the bottom of the hole, or shallower than this. The depth of the hole may be such that a part of the surface of the reinforcing bar is exposed by the unevenness of the bottom of the hole and the position of the reinforcing bar can be recognized.

  The invention according to claim 5 includes a step of cutting a hole from a surface of an existing concrete member at a depth reaching a reinforcing bar embedded in the concrete member, and a small-diameter hole having an inner diameter smaller than the hole, Cutting to a predetermined depth or through the concrete member, and inserting an anchor bolt into the small-diameter hole, and fixing the anchor bolt so as not to come out by a filler, or in the small-diameter hole A step of engaging the anchor bolt with a concrete member so as to prevent the anchor bolt from coming out, and a steel pipe having a through hole at a position corresponding to the hole and surrounding the through hole; The welded steel plate is brought into contact with the surface of the concrete member, and the steel pipe joined to the steel plate so that the axis is substantially perpendicular is inserted into the hole. The nut is inserted into the inner end of the steel pipe and a through hole provided in the steel plate, and is screwed into a male screw portion formed at a rear end portion protruding from the concrete member of the anchor bolt. And pressing the steel plate against the concrete member side, and filling a filler between the outer peripheral surface of the steel pipe and the inner peripheral surface of the hole and inside the steel pipe. Provide a fixing method.

  In this method, a small-diameter hole for embedding an anchor bolt can be formed without cutting the reinforcing bar. Then, near the surface of the concrete member, an anchor having a large outer diameter and a small-diameter anchor bolt embedded deeply into the concrete member is firmly fixed. Moreover, the steel pipe previously fixed integrally with the additional member can be firmly fixed to the concrete member together with the additional member as a part of the anchor.

  As described above, the anchor of the present invention has a large shear resistance and can firmly support the additional member with a small number. In the anchor fixing method of the present invention, a hole for fixing the anchor can be drilled in the concrete member without damaging the reinforcing bar embedded in the concrete member, and the anchor has a large shear resistance. It can be.

It is a schematic sectional drawing which shows the steel bracket fixed to the concrete member with the anchor which concerns on this invention. It is an expanded sectional view of the anchor which fixes the steel bracket shown in FIG. It is a schematic sectional drawing which shows the process of providing the anchor shown in FIG. It is a schematic sectional drawing which shows the process of providing the anchor shown in FIG. It is a schematic sectional drawing which shows the process of providing the anchor shown in FIG. It is sectional drawing which shows the state which fixed the additional member to the concrete member with the anchor which is other embodiment of this invention. It is a schematic sectional drawing which shows the process of providing the anchor shown in FIG. It is a schematic sectional drawing which shows the process of providing the anchor shown in FIG. It is a schematic sectional drawing which shows the process of providing the anchor shown in FIG. It is a schematic sectional drawing which shows the steel bracket fixed to the concrete member with the conventional anchor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing a steel bracket fixed to a concrete member by an anchor according to the present invention. FIG. 2 is an enlarged cross-sectional view of an anchor for fixing the steel bracket shown in FIG.
This steel bracket 2 is attached to the vertical surface 3a of the concrete member 3 by an anchor 1, and the anchor 1 is provided with two steps in the vertical direction and two or more rows in the lateral direction.
The steel bracket 2 has an abutment plate 2a that abuts against the vertical surface 3a of the concrete member 3, and an abutment portion 2b is provided on the abutment plate 2a. The load is supported.

  The anchor 1 is formed by cutting a hole 3b in an existing concrete member 3 and inserting a steel pipe 11 having a tip embedded in the hole 3b, inside the steel pipe 11 and deeper from the bottom of the hole 3b. From the anchor bolt 12 inserted and fixed in the small-diameter hole 3c cut to a position, the bearing plate 13 in which the anchor bolt 12 is inserted into the through hole in the center, and the concrete member 3 of the anchor bolt 12 Screwed into a male screw portion 12a formed at the protruding rear end portion, and screwed into a nut 14 pressing the support plate 13 against the rear end surface of the steel pipe 11, and a male screw formed on the outer peripheral surface of the steel pipe 11. And a second nut 15.

The steel pipe 11 is inserted and fixed in a hole 3b cut from the surface of an existing concrete member 3. The hole 3b can be cut using a core drill or the like, and has an inner diameter slightly larger than the outer diameter of the steel pipe 11. Then, both are fixed to each other via a filler 16 that is applied to the outer peripheral surface of the steel pipe 11 or the inner peripheral surface of the hole, or both, and hardened after the steel pipe 11 is inserted into the hole 3b. As the filler 16, for example, a synthetic resin such as an epoxy resin or mortar can be used.
Further, the length of the steel pipe 11 is larger than the depth of the hole 3b, and the rear part protrudes from the surface of the concrete member 3 in a state where the tip part is inserted and fixed in the hole 3b. A male screw is formed at a portion protruding from the surface of the concrete member 3, and the second nut 15 is screwed together.

The anchor bolt 12 is a rod-shaped steel member having a circular cross section, and is preferably provided with a plurality of recesses at the tip so as not to come out from the small diameter hole 3c.
This anchor bolt 12 is inserted from the tip into a small-diameter hole 3c cut from the bottom of the hole 3b into which the steel pipe 11 is inserted to a deeper position, and is fixed so as not to come out by the hardened filler 17. . The small-diameter hole 3c has an inner diameter smaller than that of the hole 3b, and can be provided by using existing means capable of drilling in concrete, such as a core drill or a hammer drill, like the hole 3b. As the filler 17 for fixing the anchor bolt 12 in the small-diameter hole 3c, a synthetic resin such as an epoxy resin can be used as in the case of fixing the steel pipe 11.

  The bearing plate 13 is a steel plate member having a circular through-hole at the center, and the anchor bolt 12 is inserted into the through-hole, and is in contact with the rear end surface of the steel pipe 11 inserted into the hole 3b. Yes. The nut 14 is screwed to the rear end portion of the anchor bolt 12, abuts against the support plate 13, and presses the steel pipe 11 toward the concrete member 3 through the support plate 13.

  Further, the inside of the steel pipe 11 is filled with a filler 18 and fixed integrally with the anchor bolt 12 inserted through the inside of the steel pipe 11 by hardening of the filler 18.

  The steel bracket 2, that is, the additional member, fixed to the concrete member 3 by the anchor 1 having the above-described configuration has a contact plate 2a that contacts the surface of the concrete member 3, and is provided on the contact plate 2a. The steel pipe 11 is inserted through the through-hole. Then, the second nut 15 is tightened, and the contact plate 2 a of the steel bracket 2 is pressed against the surface 3 a of the concrete member 3 to be fixed. Further, between the contact plate 2a and the surface 3a of the concrete member, and between the outer peripheral surface of the steel pipe 11 and the inner peripheral surface of the through hole provided in the contact plate 2a of the steel bracket, mortar or epoxy resin A filler such as is inserted and hardened. Thereby, the space between the contact plate 2a and the surface 3a of the concrete member and between the outer peripheral surface of the steel pipe and the inner peripheral surface of the through hole provided in the contact plate 2a of the steel bracket is filled with the hardened filler. The force can be transmitted through the filler.

  When a force P in the direction along the surface 3a of the concrete member acts on the steel bracket 2 fixed to the concrete member 3 by the anchor 1, the contact plate 2a fastened by the second nut 15 and the surface of the concrete member The steel bracket 2 is supported by the adhesive force and frictional force between 3 a and the shear resistance of the anchor 1. That is, the anchor 1 resists the shearing force as a synthetic member in which the steel pipe 11, the anchor bolt 12 and the filler 18 hardened in the steel pipe are integrated, and transmits the force acting on the steel pipe to the concrete member 3. At this time, on the back side 1a in the direction in which the force acts on the anchor 1, a supporting pressure acts between the outer peripheral surface of the steel pipe 11 and the concrete, but the outer diameter of the steel pipe 11 is a conventional one as shown in FIG. It is sufficiently larger than the outer diameter of the anchor bolt in the anchor structure, and the supporting pressure is kept small. Further, although the steel pipe 11 is embedded in the concrete member 3 in a small length, it is restrained from being pulled out of the concrete member 3 by the anchor bolt 12, the bearing plate 13 and the nut 14, and resists the force P. To be.

Next, the process of providing the anchor 1 as described above on the concrete member 3 will be described with reference to FIGS.
In order to install the anchor 1, first, a hole 3 b for inserting the steel pipe 11 is provided at a position where the steel bracket 2 of the concrete member 3 is to be attached. As shown in FIG. 3A, the hole 3b is slightly larger than the outer diameter of the steel pipe 11, and has a depth reaching the reinforcing bar 3d embedded near the surface 3a of the concrete member. Moreover, it is set as the depth which does not damage the reinforcing bar 3d by cutting of the hole 3b. By providing this hole 3b, the position of the reinforcing bar 3d can be confirmed, and the small diameter hole 3c for inserting and fixing the anchor bolt 12 from the bottom of the hole 3b to avoid the position of the reinforcing bar 3d to a deeper position. To cut. At this time, the small diameter hole 3c is not necessarily provided at the center of the large diameter hole 3b. The position where the reinforcing bar 3d is disposed can be avoided, and it can be provided at a position off the center.
In addition, the hole 3b for inserting the steel pipe is a hole regardless of the depth at which the reinforcing bar is disposed when it is clear that the concrete member is unreinforced concrete or the reinforcing bar is not in a position where the reinforcing bar is cut. The depth of can be set.

  When the small-diameter hole 3c is cut, as shown in FIG. 3B, the anchor bolt 12 is inserted into the small-diameter hole 3c from the tip, and a filler such as epoxy resin is filled into the small-diameter hole 3c and solidified. Then, the anchor bolt 12 is fixed to the concrete member 3. Subsequently, as shown in FIG. 4A, the steel pipe 11 is inserted into the hole 3b having a large diameter from the tip and fixed. The steel pipe 11 is fixed by applying a filler such as an epoxy resin to the outer peripheral surface of the steel pipe 11 or the inner peripheral surface of the hole 3b, or both of them, and inserting the steel pipe 11 into the hole so that the outer peripheral surface of the steel pipe 11 is inserted. And the inner peripheral surface of the hole are filled with the filler 16. The filler may be injected using an injection tube or the like.

  When the steel pipe 11 is fixed to the concrete member 3 by the hardening of the filler 16, the steel bracket 2 is brought into contact with the surface 3a of the concrete member at a predetermined position. The steel bracket 2 includes a contact plate 2a made of steel at a position where the steel bracket 2 contacts the surface 3a of the concrete member. As shown in FIG. 4B, the steel bracket 2 has a through hole provided in the contact plate 2a. The abutting plate 2a is brought into contact with the concrete member 3 through the steel pipe 11 of the anchor. Moreover, the 2nd nut 15 is screwed together with the external thread currently formed in the steel pipe 11 at the outer peripheral surface. When the contact plate 2a is brought into contact with the surface 3a of the concrete member, a filler or adhesive such as epoxy resin is applied to the surface 3a of the concrete member in advance or the surface of the contact plate 2a that comes into contact with the concrete member 3 or both of them. Apply. Further, the inner surface of the steel pipe 11 or the inner surface of the through hole of the contact plate 2a is filled with the filler between the inner peripheral surface of the through hole provided in the contact plate 2a and the outer peripheral surface of the steel tube 11. A filler is applied to the peripheral surface or both of them.

As shown in FIG. 5A, the anchor bolt 12 is inserted through the through hole of the support plate 13, and the support plate 13 is brought into contact with the rear end surface of the steel pipe 11. Then, a nut 14 is screwed into a male screw formed at the rear end portion of the anchor bolt 12, and the steel pipe 11 is pressed against the concrete member 3 side by being fastened to the bearing plate 13. After the nut 14 is tightened, the second nut 15 is tightened, and the contact plate 2a of the steel bracket is pressed against the surface 3a of the concrete member and fixed.
When the bearing plate 13 is brought into contact with the rear end surface of the steel pipe 11, the bearing plate 13 is eccentric with respect to the steel pipe 11 unless the small diameter hole 3 c is provided at the center of the large diameter hole 3 b. Even if there is eccentricity, the bearing plate 13 is set to a size that contacts the entire rear end surface of the steel pipe 11 and can be pressed against the entire rear end surface of the steel pipe 11.

  Thereafter, as shown in FIG. 5 (b), the injection tube 13 b is attached to the injection hole 13 a provided in the bearing plate 13, and the filler 18 is injected into the steel tube 11. As the filler 18, mortar, cement milk, synthetic resin, or the like can be used. The setting of the anchor 1 and the attachment of the steel bracket 2 are completed when the filler 18 is cured.

  In such an anchor 1, since the depth of the hole 3b having a large diameter is shallower than the position of the reinforcing bar 3d embedded in the concrete member 3, it is provided at an accurate position without being affected by the position of the reinforcing bar 3d. be able to. Therefore, if the through holes provided in the abutting plate 2a of the steel bracket 2 are formed in accordance with the positions of the steel pipes 11 inserted into the holes 3b having a large diameter, the steel pipes 11 are inserted into these through holes and the steel is inserted. The bracket 2 can be brought into contact with the concrete member 3. The position of the small-diameter hole 3c provided avoiding the position of the reinforcing bar 3d is influenced by the position of the reinforcing bar 3d, and the exact position cannot be determined until actual cutting, but the anchor bolt 12 and the steel pipe 11 are allowed to be eccentric. The Therefore, it is not necessary to provide the through hole of the contact plate according to the position where the anchor bolt is actually installed as in the prior art.

FIG. 6 is a cross-sectional view showing a state in which a contact plate 32 of a steel bracket as an additional member is fixed to a concrete member 33 by an anchor 31 according to another embodiment of the present invention.
The anchor 31 includes a steel pipe 41 inserted into a hole 33b cut to a depth reaching the reinforcing bar 33d embedded in the concrete member 33, and a small-diameter hole 33c cut from the bottom of the hole 33b to a deeper position. The anchor bolt 42 is inserted and fixed, the support plate 43 in which the anchor bolt 42 is inserted into the through hole in the center portion, and the rear end portion of the anchor bolt 42 protruding from the concrete member 33. And a nut 44 that is screwed into the male threaded portion and abutted against the support plate 43. The steel pipe 41 is fixed to the contact plate 32 of the steel bracket by welding. The bearing plate 43 is pressed against the contact plate 32 of the steel bracket, and the contact plate 32 is pressed against the surface 33a of the concrete member 33 to be fixed.

  The anchor bolt 42 is inserted into the small-diameter hole 33c from the tip, similarly to the anchor 1 shown in FIG. 2, and is fixed to the concrete member 33 by a hardened filler 47. Although the rear end portion of the anchor bolt 42 protrudes from the surface of the concrete member 33, the protruding length is shorter than the anchor 1 shown in FIG.

  A contact hole 32 of the steel bracket is provided with a through hole, and the steel pipe 41 is joined so as to surround the through hole. That is, it joins so that it may lead to the inner side of the steel pipe 41 from a through-hole, The position where this steel pipe 41 was joined respond | corresponds with the position where the hole 33b with a large diameter was provided in the concrete member 33. FIG. The contact plate 32 is brought into contact with the surface 33 a of the concrete member, and the steel pipe 41 is inserted into a hole 33 b having a large diameter formed in the concrete member 33. The anchor bolt 42 inserted and fixed in the small-diameter hole 33 c is inserted into a through hole provided in the steel pipe 41 and the contact plate 32 and protrudes rearward from the contact plate 32. A support plate 43 having a through hole is attached to a protruding portion of the anchor bolt 42, and a nut 44 is screwed.

  On the other hand, the length of the steel pipe 41 and the depth of the hole 33b are set so that the front end surface of the steel pipe 41 inserted into the hole 33b is opposed to the bottom surface of the hole 33b with a gap. In addition, the diameter of the hole 33b into which the steel pipe 41 is inserted is set so that an interval is provided between the inner peripheral surface and the outer peripheral surface of the steel pipe 41 so that the filler 46 can be injected.

  The bearing plate 43 is brought into contact with the abutting plate 32 of the steel bracket by tightening the nut 44, and the abutting plate 32 of the steel bracket is pressed against and fixed to the surface 33a of the concrete member. Even when the small-diameter hole 33c into which the anchor bolt 42 is inserted is eccentric with respect to the large-diameter hole 33b avoiding the reinforcing bar 33d, the bearing plate 43 contacts the contact plate 32 over the entire area around the through-hole. It is to be touched.

  The bearing plate 43 is provided with an injection hole 43a for a filler 46. The filler 46 injected from the injection hole 43a is filled inside the steel pipe 41 and wraps around the steel pipe 41 from the tip to the outside. The space between the outer peripheral surface of 41 and the inner peripheral surface of the hole 33b provided in the concrete member 33 is also filled.

Such an anchor can be provided by the following process.
As in the anchor shown in FIG. 2, a hole 33b having a large diameter into which the steel pipe 41 is inserted is formed at a position where the anchor of the concrete member 33 is provided. The hole 33b is provided at a depth that reaches the reinforcing bar 33d embedded near the surface of the concrete member 33, and a small-diameter hole 33c that fixes the anchor bolt 42 from the bottom of the hole 33b is formed by avoiding the position of the reinforcing bar 33d. To do. Then, as shown in FIG. 7A, the anchor bolt 42 is inserted into the small-diameter hole 33c and fixed to the concrete member 33 by hardening of the filled filler 47.

  As shown in FIG. 7B, the steel bracket to be fixed to the concrete member 33 is obtained by joining a steel pipe 41 to the contact plate 32 by welding and bringing it into contact with the concrete member 33. That is, the abutting plate 32 is brought into contact with the surface 33a of the concrete member, the steel pipe 41 is inserted into the hole 33b, and the anchor bolt 42 fixed to the concrete member 33 is inserted into the steel pipe 41.

  As shown in FIG. 8A, the anchor bolt 42 is fitted with a support plate 43, and a nut is screwed together. Then, as shown in FIG. 8 (b), the nut 44 is fastened to the bearing plate 43, and the contact plate 32 is pressed against the surface 33a of the concrete member to fix the steel bracket. After that, as shown in FIG. 9, the filler 46 is injected from the injection hole 43 a provided in the bearing plate 43 to fill the inside of the steel pipe 41, and the filler is also applied to the outside of the steel pipe 41 from the tip of the steel pipe 41. The filler 46 is also filled between the outer peripheral surface of the steel pipe 41 and the inner peripheral surface of the hole 33b. When the filler 46 is hardened, the anchor bolt 42, the steel pipe 41, and the abutting plate 32 of the steel bracket are fixed integrally, and the installation of the anchor 31 and the fixing of the steel bracket are completed.

  Such an anchor 31 resists a load acting on the steel bracket contact plate 32 by a composite member of the steel pipe 41, the anchor bolt 42, and the filler 46 coupled to the steel bracket contact plate 32. . Accordingly, the number of anchors 31 can be reduced, and the holes 33c for fixing the anchor bolts 42 can be formed without damaging the reinforcing bars 33d embedded in the existing concrete members 33. In addition, by fixing the steel pipe 41 to the steel bracket as an additional member in advance, the number of parts can be reduced, and the process of fixing the steel bracket to the concrete member 33 by the anchor 31 can be performed efficiently.

In the embodiment described above, the concrete members 3 and 33 are provided with the small-diameter holes 3c and 33c having a predetermined depth, and the anchor bolts 12 and 42 are inserted and fixed. However, the small-diameter holes 3c, Instead of 33c, a hole penetrating the concrete member may be provided. When the through hole is provided, an anchor bolt can be inserted into the through hole from the tip, and a plate, a nut or the like can be attached to the penetrating tip to resist backward pulling.
Further, the additional member fixed to the concrete member by the anchor of the present invention includes a bracket for supporting a load in the vertical direction such as a working scaffold and a support work, and a bracket to which a tension material for introducing prestress is fixed. can do. Moreover, the structure which supports the facilities added by repair of a structure etc., for example, the support | pillar of an illumination lamp, etc. may be sufficient.
In addition, the present invention is not limited to the above-described aspects, and can be implemented in various aspects.

1: Anchor, 2: Steel bracket, 3: Concrete member, 3a: Surface of concrete member (vertical surface), 3b: Large diameter hole for inserting steel pipe, 3c: Small diameter hole for inserting anchor bolt, 3d: Concrete member Embedded in the rebar,
11: Steel pipe, 12: Anchor bolt, 13: Bearing plate, 14: Nut, 15: Second nut, 16: Filler, 17: Filler, 18: Filler,
31: Anchor, 32: Abutting plate of steel bracket, 33: Concrete member, 33a: Surface of concrete member, 33b: Large diameter hole for inserting steel pipe, 33c: Small diameter hole for inserting anchor bolt, 33d: Concrete member Embedded in the rebar,
41: Steel pipe, 42: Anchor bolt, 43: Bearing plate, 44: Nut, 46: Filler, 47: Filler

Claims (5)

A steel pipe inserted into a hole cut from a surface of an existing concrete member to a predetermined depth in the concrete member;
Inserted from the bottom of the hole to a deeper position with an inner diameter smaller than the hole or into a small-diameter hole cut so as to penetrate the concrete member, fixed so as not to come out, and inserted inside the steel pipe Anchor bolts,
A nut that is screwed into a male thread formed at an end projecting from the concrete member of the anchor bolt and restrains the steel pipe so as not to come out of the concrete member;
An anchor, wherein a filler is filled and hardened between an outer peripheral surface of the steel pipe and an inner peripheral surface of the hole and inside the steel pipe. A male screw is formed on the outer peripheral surface of the steel pipe, and a second nut is screwed onto the male screw.
The steel pipe is inserted into a through hole provided in the additional member supported by the concrete member, the additional member is sandwiched between the second nut and the concrete member, and the second nut is tightened to add the additional member. The anchor according to claim 1, wherein the anchor supports the member. A steel plate that is brought into contact with the surface of the concrete member is fixed to the rear end of the steel pipe whose tip is inserted into the hole,
The steel plate constitutes a part of the additional member,
The anchor according to claim 1, wherein the steel plate is pressed against the concrete member side by tightening a nut screwed to the anchor bolt. Cutting the hole from the surface of the existing concrete member at a depth reaching the reinforcing bars embedded in the concrete member;
Cutting a small diameter hole having an inner diameter smaller than the hole from the bottom of the hole to a predetermined depth or penetrating the concrete member;
Insert an anchor bolt into the small-diameter hole and fix the anchor bolt so that it does not come out with a filler, or let the anchor bolt penetrate through the small-diameter hole and insert the tip through the anchor bolt so that it does not come out. Locking to the member;
A steel pipe is inserted into the hole, and a nut to be screwed into a male thread portion formed at a rear end protruding from the concrete member of the anchor bolt is tightened in a state of being locked to the steel pipe, and the steel pipe is fastened to the concrete member Pressing the side and fixing the steel pipe to the concrete member by curing the filler filled between the outer peripheral surface of the steel pipe and the inner peripheral surface of the hole;
Filling the inside of the steel pipe with a filler. Cutting the hole from the surface of the existing concrete member at a depth reaching the reinforcing bars embedded in the concrete member;
Cutting a small-diameter hole having an inner diameter smaller than the hole from the bottom of the hole to a predetermined depth, or penetrating the concrete member;
Insert an anchor bolt into the small-diameter hole and fix the anchor bolt so that it does not come out with a filler, or let the anchor bolt penetrate through the small-diameter hole and insert the tip through the anchor bolt so that it does not come out. Locking to the member;
A steel plate having a through hole at a position corresponding to the hole and welded with a steel pipe so as to surround the through hole is brought into contact with the surface of the concrete member so that the axis is substantially perpendicular to the steel plate. The joined steel pipe is inserted into the hole, and the anchor bolt is inserted into the inside of the steel pipe and the through hole provided in the steel plate, and formed at the rear end portion protruding from the concrete member of the anchor bolt. Tightening a nut to be screwed into the male thread portion and pressing the steel plate against the concrete member side;
Filling the filler between the outer peripheral surface of the steel pipe and the inner peripheral surface of the hole and inside the steel pipe.

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