Anchor hole drilling device with oval recesses and protrusions, and anchor hole drilling method with oval recesses and protrusions

Abstract

To provide an oval type ruggedness-fitted anchor hole drilling device capable of drilling a ruggedness-fitted anchor hole having high fixing power with respect to a concrete structure of a reinforcement material.SOLUTION: In an anchor hole drilling device 1, longitudinal movement means 5 running on a base plate 3 and longitudinally moving guide means 4 and a drilling machine body 2 to the longitudinal two directions of one direction orthogonal to a rotary shaft 22 is provided, a recessed part formation fixture 6 simultaneously forming plural recessed parts at the inner circumferential face of a drilled anchor hole h1 can be fitted to the rotary shaft 22, the recessed part formation fixture 6 comprises: a shaft body made of a bar stock fittable to the rotary shaft; and plural circular blades projecting in a disk shape to the outside, while rotatively driving the recessed part formation fixture 6 by the drilling machine body 2, the guide means 4 and the drilling machine body 2 are longitudinally moved by the longitudinal movement means 5 to form oval type ruggedness formed with the recessed parts in the longitudinal two directions at the anchor hole.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an oval-shaped uneven anchor hole drilling device, a method for drilling oval-shaped uneven anchor holes, and a concrete structure in which oval-shaped uneven anchor holes are formed, and more particularly to an oval-shaped uneven anchor hole drilling device that can drill uneven anchor holes in a short period of time that have high fixing power for reinforcing material to concrete structures, a method for drilling oval-shaped uneven anchor holes, and a concrete structure in which oval-shaped uneven anchor holes are formed. [Background technology]

[0002] Conventionally, in order to ensure the anchoring of fiber reinforcement or reinforcing bars, a method is known in which holes are drilled into a concrete structure to install a reinforcing material, and the concrete structure and the reinforcing material are integrated with a hardening material such as epoxy resin. In this case, if it is desired to enhance the reinforcing effect by using a high-strength reinforcing material such as carbon fiber, for example, it is necessary to increase the anchoring length according to the tensile strength of the reinforcing material.

[0003] However, depending on the installation location of the concrete structure, the required anchorage length cannot always be secured, and it is required to shorten the required anchorage length. For this reason, it is known to perform uneven processing on the drilled hole to improve the anchorage strength. However, in order to form an uneven anchor hole with high anchorage strength, it is necessary to drill a normal circular anchor hole, and then press a special jig to form recesses one step at a time on the inner surface of the anchor hole, which causes the problem that it takes a long time to drill one uneven anchor hole.

[0004] For example, Patent Document 1 discloses an expansion groove forming device 14 proposed by the present applicant, which forms an anchor hole with projections and recesses by swinging a head 15 having bits 13 spaced apart in the circumferential direction of a disk-shaped portion 12 in a swinging motion, and also shifting its position in the axial direction of the anchor hole 4 and swinging the head 15 in a swinging motion in a similar manner (see paragraph

[0018] of the specification of Patent Document 1, Figure 2 of the drawings, etc.).

[0005] However, although the expansion groove forming device 14 described in Patent Document 1 can form recesses in multiple stages, it still takes time to form the uneven anchor holes, and there is a problem in that the work efficiency is poor. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2006-45997 A Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, the present invention has been devised in consideration of the above-mentioned problems, and an object of the present invention is to provide an oval-shaped uneven anchor hole drilling device and a method for drilling oval-shaped uneven anchor holes that can drill uneven anchor holes with high fixing power for reinforcing material in concrete structures in a short period of time, and a concrete structure in which oval-shaped uneven anchor holes are formed. [Means for solving the problem]

[0008] The oval-shaped uneven anchor hole drilling device according to claim 1 is an anchor hole drilling device comprising a drilling machine body having a drive means for rotating a rotating shaft, a base plate for fixing the drilling machine body to a concrete structure, and a guide means arranged on the base plate for guiding the drilling machine body in the axial direction of the rotating shaft, and further comprising forward and backward moving means for moving the guide means and the drilling machine body forward and backward in sequence in one direction perpendicular to the rotating shaft by running on the base plate, and a recess forming jig for simultaneously forming a plurality of recesses on the inner peripheral surface of a drilled anchor hole can be attached to the rotating shaft, and the recess forming jig comprises a shaft body made of a rod material that can be attached to the rotating shaft, and a guide means for moving the guide means and the drilling machine body forward and backward in one direction perpendicular to the rotating shaft. In the length direction At a specified interval From the outer periphery of the shaftand a plurality of circular blades protruding outward in a disk shape, and while the drilling machine body rotates and drives the recess forming jig, the guide means and the drilling machine body are moved back and forth by the forward and backward movement means to form recesses in the anchor hole in two directions forward and backward. Plane view oval It is characterized by forming oval-shaped projections and recesses.

[0009] The oval-shaped uneven anchor hole drilling device of claim 2 is the oval-shaped uneven anchor hole drilling device of claim 1, characterized in that the recess forming jig has the circular blades formed at predetermined intervals in the longitudinal direction of the shaft and over a length greater than the required fixing length of the anchor hole.

[0010] The method for drilling an oval-shaped uneven anchor hole according to claim 3 is carried out by using the oval-shaped uneven anchor hole drilling device according to claim 1 or 2. Plane view oval A method for drilling an oval-shaped uneven anchor hole for drilling an oval-shaped uneven anchor hole, the method comprising: an anchor hole drilling step of attaching a core bit to the rotating shaft to drill an anchor hole; a jig replacement step of attaching the recess forming jig to the rotating shaft in place of the core bit without removing the base plate from the concrete structure; and a step of inserting the recess forming jig into the anchor hole drilled in the anchor hole drilling step, and moving the guide means and the drilling machine body forward and backward by the forward and backward movement means while rotating and driving the recess forming jig with the drilling machine body, thereby forming recesses in two directions, forward and backward, on the inner peripheral surface of the anchor hole. Plane view oval The method is characterized by carrying out a recess formation step to form oval recesses and protrusions. Effect of the Invention

[0012] Claim 1~ 3 According to the invention, a core drill bit is attached to a drilling machine to drill an anchor hole, and a recess forming jig is attached to the drilling machine without re-piling, and the jig is rotated while moving forward and backward with the forward and backward moving means, thereby forming an oval anchor hole with recesses formed only in the forward and backward directions on the inner peripheral surface of the anchor hole in a short time. Therefore, an uneven anchor hole with high fixing power for the reinforcing material to the concrete structure can be drilled in a short time.

[0013] In particular, according to the invention of claim 2, the recess forming jig has a circular blade formed over a length greater than the required fixing length of the anchor hole, so that the necessary recess can be formed over the entire length of the anchor hole with the recess forming jig, and therefore an anchor hole with projections and recesses having high fixing power can be drilled in an even shorter time. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a side view showing an oval-shaped embossed anchor hole drilling device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a side view showing only the recess forming jig of the oval-shaped uneven anchor hole drilling device, where (a) is the recess forming jig of the first embodiment and (b) is the recess forming jig of the second embodiment. [Diagram 3] FIG. 3 is a horizontal cross-sectional view showing the recess forming jig of the same. [Figure 4] FIG. 4 is a process explanatory diagram showing the anchor hole drilling process of the oval embossed anchor hole drilling method according to the embodiment of the present invention. [Diagram 5] FIG. 5 is a process explanatory diagram showing a jig replacement process in the above-mentioned oval-shaped uneven anchor hole drilling method. [Figure 6] FIG. 6 is a process explanatory diagram showing a recess forming process in the above-mentioned oval uneven anchor hole drilling method. [Figure 7] FIG. 7 is a diagram showing a concrete structure in which an oval embossed anchor hole has been formed after completion of the above-mentioned oval embossed anchor hole drilling method. [Figure 8] FIG. 8 is a photograph showing the anchor pull-out test. [Figure 9] FIG. 9 is a photograph showing the fracture morphology after the anchor pull-out test. [Figure 10] FIG. 10 is a load-displacement graph showing the test results of the anchor pull-out test. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, embodiments of the oval-shaped uneven anchor hole drilling device, the oval-shaped uneven anchor hole drilling method, and the concrete structure in which the oval-shaped uneven anchor hole is formed according to the present invention will be described in detail with reference to the drawings.

[0016] <Oval-shaped uneven anchor hole drilling device> First, an oval-shaped uneven anchor hole drilling device 1 (hereinafter, simply referred to as a hole drilling device 1) according to an embodiment of the present invention will be described with reference to Figs. 1 to 3. Fig. 1 is a side view of the oval-shaped uneven anchor hole drilling device according to an embodiment of the present invention, and Fig. 2 is a side view showing only the recess forming jig of the hole drilling device 1, where (a) is the recess forming jig according to the first embodiment, and (b) is the recess forming jig according to the second embodiment. Fig. 3 is a horizontal cross-sectional view showing the recess forming jigs 6, 6' in Figs. 2(a) and (b) (the same for both the first and second embodiments).

[0017] As shown in Fig. 1, the hole drilling device 1 according to this embodiment is a stationary type drilling machine that is fixed to the surface of a concrete structure C1 such as a reinforced concrete structure and drills relatively large diameter holes such as anchor holes h1 in the concrete structure C1. This hole drilling device 1 comprises a drilling machine body 2, a base plate 3 for fixing this drilling machine body 2 to the concrete structure C1, and a guide means 4 erected on this base plate 3 for guiding the drilling machine body 2. The hole drilling device 1 also comprises forward and backward movement means 5 for moving the guide means 4 and the drilling machine body 2 forward and backward in one direction.

[0018] (Drilling machine body) The drilling machine body 2 is a main component of the drilling device 1, in which a drive motor 21, which is a driving means, is housed within a housing 20, and is a device that rotates a rotating shaft 22, which is a spindle, using the drive motor 21. A core bit 24, which will be described later, and recess forming jigs 6, 6' according to the embodiment can be attached to this rotating shaft 22 by screwing them via a coupling 23 (reducer).

[0019] (Base plate) The base plate 3 is a base plate that is drilled into the concrete structure C1 and then fixed with an installed anchor. Of course, in places where it is not possible to drill anchor holes in the concrete structure C1 to fix the drilling device 1, it may be a suction pad that is vacuum-adsorbed and fixed to the concrete structure C1. Reference numeral 31 denotes a height adjustment bolt 31 for adjusting the horizontal or vertical orientation of the base plate 3 according to the unevenness (unevenness) of the external surface of the concrete structure C1.

[0020] (Guide Means) The guide means 4 is supported and fixed by the base plate 3, and is based on a support pillar 40 that is erected perpendicular to the plate surface of the base plate 3, and has the function of guiding the drilling machine main body 2 in the axial direction of the rotation shaft 22.

[0021] A rack 41 is formed on the support 40 along the longitudinal direction of the support 40. The guide means 4 is provided with a holder 42 that has a gear (not shown) that meshes with the rack 41 and is integrated with the housing 20 to surround the periphery of the support 40. The holder 42 supports the drilling machine body 2 without shaking by surrounding the support 40, and has the function of moving up and down along the support 40 in a stepwise and quantitative manner (moving toward or away from the concrete structure C1) by meshing with the rack 41.

[0022] Reference numeral 43 denotes a feed handle 43 for manually rotating a gear meshing with the rack 41 to move the holder 42 up and down.

[0023] (Forward / backward movement means) The forward / backward movement means 5 has a drive motor, and is a means for traveling on the base plate 3 to move the guide means 4 and the drilling machine main body 2 forward and backward in the illustrated X direction, which is one direction perpendicular to the rotation axis 22. Here, the X direction refers to a direction perpendicular to the rotation axis 22, which connects the central axis of the support 40 with the central axis of the rotation axis 22, as shown in Figure 1. The direction moving forward along this X direction away from the base plate 3 toward the rotation axis 22 is the forward movement direction X1, and the direction moving backward toward the base plate 3 along the X direction is the backward movement direction X2.

[0024] (Recess formation jig) 2, the recess forming jig 6 (6') has a shaft body 60 (60') made of a rod material that can be attached to the aforementioned rotating shaft 22, and a plurality of circular blades 61 (61') that protrude outward in a disk shape at predetermined intervals in the longitudinal direction from the outer periphery of the shaft body 60 (60'). In the illustrated embodiment, the circular blades 61 (61') are formed with a center-to-center distance of 25 mm at a pitch.

[0025] As shown in Fig. 3, the circular blade 61 (61') has a plurality of arc-shaped notches 62 (62') (six in the illustrated embodiment). Therefore, as described later, the circular blade 61 (61') rotates and comes into contact with the inner peripheral surface of the anchor hole h1 of the concrete structure C1, thereby chipping away and scraping away the concrete from the notches 62 (62'). In other words, the recess forming jig 6 (6') has the function of simultaneously forming a plurality of recesses on the inner peripheral surface of the anchor hole h1. The protruding distance D1 of the circular blade 61 (61') from the outer periphery of the shaft body 60 (60') is 5 mm.

[0026] In the illustrated embodiment, the recess forming jig 6 (6') has 16 circular blades formed at a pitch of 25 mm, and the circular blades 61 (61') are formed over a length greater than the required anchor hole h1 fixing length. Therefore, the recess forming jig 6 (6') can form the recess required for the anchor hole h1 in one go. The required anchor hole h1 fixing length is determined appropriately according to the tensile strength of the reinforcing material, and is obtained from a pull-out test described later.

[0027] The only difference between the recess forming jig 6 according to the first embodiment shown in Fig. 2(a) and the recess forming jig 6' according to the second embodiment shown in Fig. 2(b) is the thickness of the circular blade 61 (61'). In the illustrated embodiment, the thickness t1 of the circular blade 61 of the recess forming jig 6 is 5 mm, and the thickness t2 of the circular blade 61' of the recess forming jig 6' is 10 mm.

[0028] <How to drill oval-shaped uneven anchor holes> Next, a method for drilling an oval embossed anchor hole according to an embodiment of the present invention will be described with reference to Figs.

[0029] (Anchor hole drilling process) 4 is a process explanatory diagram showing the anchor hole drilling process of the oval-shaped uneven anchor hole drilling method according to the embodiment of the present invention. As shown in FIG. 4, in the oval-shaped uneven anchor hole drilling method according to the embodiment, first, an anchor hole drilling process is performed to drill an anchor hole h1 in a concrete structure C1.

[0030] Specifically, as shown in Fig. 4, a core bit 24 for drilling a normal anchor hole is attached to the rotating shaft 22 of the above-mentioned hole drilling device 1, and the core bit 24 is rotated and driven by the drive motor 21. Then, using the guide means 4 and feed handle 43 of the hole drilling device 1, the core bit 24 is pressed against the concrete structure C1 along the axial direction of the rotating shaft 22 while rotating, to drill an anchor hole h1 that is circular in plan view.

[0031] (Jig replacement process) Next, as shown in Fig. 5, in the method for drilling an oval uneven anchor hole according to this embodiment, a jig replacement step is performed in which the recess forming jig 6 described above is attached to the rotating shaft 22 instead of the core bit 24. Fig. 5 is a process explanatory diagram showing the jig replacement step in the method for drilling an oval uneven anchor hole according to an embodiment of the present invention.

[0032] At this time, in this process, the core bit 24 is replaced with the recess forming jig 6 described above, without removing the base plate 3 and changing the setup, while the hole drilling device 1 is still installed on the outer surface of the concrete structure C1 with the base plate 3. Therefore, the time required for changing the setup required when forming the conventional uneven anchor hole described in Patent Document 1 is omitted, and the construction time can be shortened.

[0033] (Recess formation process) Next, as shown in Fig. 6, in the anchor hole drilling method with oval indentations according to this embodiment, a recess forming step is performed in which the guide means 4 and the drilling machine body 2 are moved back and forth by the forward and backward movement means 5 while the recess forming jig 6 is rotationally driven by the drilling machine body 2 to form oval indentations on the inner peripheral surface of the anchor hole h1. Fig. 6 is a process explanatory diagram showing the recess forming step in the anchor hole drilling method with oval indentations according to an embodiment of the present invention.

[0034] 6(a), in this process, first, the recess forming jig 6 attached to the rotating shaft 22 in the jig replacement process is inserted into the circular anchor hole h1 drilled in the anchor hole drilling process described above. At this time, when the diameter of the anchor hole h1 is φ1=32 mm, the diameter of the circular blade 61 is set to approximately 31 mm, which is approximately the diameter φ1 of the anchor hole h1.

[0035] Next, as shown in Figure 6 (b), while rotating the recess forming jig 6 with the drive motor 21 of the drilling machine main body 2, the drilling machine main body 2 together with the guide means 4 is advanced in the forward direction X1 with the forward / backward movement means 5, and the rotating circular blade 61 is pressed against the inner surface of the anchor hole h1 to cut the front recess R1.

[0036] Conversely, as shown in Figure 6 (c), while rotating the recess forming jig 6 with the drive motor 21 of the drilling machine main body 2, the drilling machine main body 2 together with the guide means 4 is retracted in the retraction direction X2 with the forward / backward movement means 5, and the rotating circular blade 61 is pressed against the inner surface of the anchor hole h1 to cut the rear recess R2.

[0037] At this time, the drilling machine body 2 may be repeatedly advanced and retreated using the forward / backward advancing / retreating means 5, and the recess forming jig 6 may cut the front recess R1 and the rear recess R2 little by little, or the cutting may be performed by advancing and retreating just once.

[0038] In any case, when the shaft 60 of the recess forming jig 6 abuts against the inner surface of the anchor hole h1, it is no longer possible for the circular blade 61 to cut the inner surface of the anchor hole h1, and the cutting work of the front recess R1 and the rear recess R2 is completed.

[0039] When this step is completed and the recess forming jig 6 is pulled up, an oval (elliptical) uneven anchor hole h1' is formed as shown in Fig. 6(d). That is, the part cut away from the circular anchor hole h1 by the circular blade 61 of the recess forming jig 6 becomes the front recess R1 and the rear recess R2, and the inner circumferential surface of the remaining circular anchor hole h1 that has not been cut away becomes the convex part, becoming an oval (elliptical) uneven anchor hole h1'. As described above, the protruding distance D1 of the circular blade 61 from the shaft body 60 is 5 mm, so that the thickest part of the crescent-shaped recess (front recess R1 and rear recess R2) is also D1 = 5 mm.

[0040] When this step is completed, all steps of the oval-shaped uneven anchor hole drilling method according to this embodiment are completed. By the oval-shaped uneven anchor hole drilling method, as shown in Fig. 7, an oval-shaped uneven anchor hole h1' is formed in the concrete structure C1, in which a plurality of crescent-shaped (see also Fig. 6) recesses (front recess R1 and rear recess R2) are formed at predetermined intervals in the upper and lower directions in the forward direction X1 and the backward direction X2 along the X direction, which is one direction perpendicular to the axial direction of the rotation shaft 22, are formed in the concrete structure C1. Fig. 7 is a diagram showing the concrete structure C1 in which the oval-shaped uneven anchor hole h1' is formed after the oval-shaped uneven anchor hole drilling method is completed.

[0041] This oval embossed anchor hole h1' differs from conventional embossed anchor holes in that it has recesses formed only in the front and rear directions, which may result in weaker adhesion and fixing strength of the reinforcing material than conventional anchor holes which have recesses formed in all directions around the circumference.

[0042] However, pull-out tests described below revealed that the oval-shaped uneven anchor hole h1', which has recesses formed in only two directions, has a pull-out strength (maximum load) that is comparable to that of an uneven anchor hole with recesses formed around the entire circumference.

[0043] Furthermore, in the pull-out test described later, it was found that the pull-out strength (maximum load) increases by changing and thickening the blade thickness of the circular blade 61. Therefore, by changing and thickening the blade thickness of the circular blade 61, it is possible to form an oval-shaped, uneven anchor hole h1' in a short time, and it is also possible to increase the pull-out strength compared to a conventional anchor hole with recesses formed in all directions.

[0044] [Construction time] Next, the construction time using the conventional expansion groove forming device described in Patent Document 1 and the construction time using the oval-shaped uneven anchor hole drilling method according to the embodiment of the present invention were measured, and the results are shown in Table 1 below.

[0045] [Table 1]

[0046] The "core" in Table 1 refers to the work time required to drill a circular anchor hole in a concrete structure using a core bit for drilling a normal anchor hole, as described above in the anchor hole drilling process.

[0047] Moreover, the unevenness processing in Table 1 is the work time for forming unevenness on the inner peripheral surface of a circular anchor hole. In other words, the unevenness processing in the conventional example is the work time for forming unevenness with the enlarged groove forming device described in Patent Document 1, and the unevenness processing in the example is the total work time for the jig replacement step and the recess formation step in the method for drilling an oval uneven anchor hole according to the above-mentioned embodiment.

[0048] As shown in Table 1, the work time using the oval-shaped uneven anchor hole drilling method according to this embodiment was able to be reduced to about half of the construction time using the conventional expansion groove forming device described in Patent Document 1.

[0049] Also, from Table 1, it can be considered that the main factor in the reduction in work time is the fact that the work time for unevenness processing, i.e., the time to form unevenness in the anchor hole, was significantly reduced. Unlike the enlarged groove forming device, the method for drilling an oval uneven anchor hole according to this embodiment smoothly transitions from the anchor hole drilling process → jig replacement process → recess forming process without changing the setup, and moreover, the recess forming jig 6 can form all the recesses required for one anchor hole at once.

[0050] According to the oval-shaped uneven anchor hole drilling device 1 and the oval-shaped uneven anchor hole drilling method using the same according to the embodiment of the present invention described above, the core bit 24 is attached to the drilling machine body 2 to drill the anchor hole h1, and the recess forming jig 6 is attached to the drilling machine body 2 without changing the filling (changing the setup), and the recess forming jig 6 is rotated while moving forward and backward by the forward and backward moving means 5, so that an oval-shaped uneven anchor hole h1' in which recesses (front recess R1 and rear recess R2) are formed only in the forward and backward directions on the inner circumferential surface of the anchor hole h1 can be formed in about half the time required by the conventional method. Therefore, an uneven anchor hole with high fixing power for the reinforcement material to the concrete structure C1 can be drilled in a short time.

[0051] [Anchor pull-out test 1] Next, we will explain anchor pull-out test 1, which was conducted to confirm whether the unevenness of the drilled hole contributes to improving the bearing strength. As shown in the photograph in Figure 8, a circular anchor hole with a diameter of 40 mm and a depth of 400 mm was drilled in a reinforced concrete specimen, and another specimen was created in which the same hole was drilled, but with a blade thickness of 5 mm and unevenness formed all around the inner surface at the same pitch of 25 mm.

[0052] Then, carbon fiber rods were inserted into these two types of anchor holes as reinforcing materials, solidified with adhesive, and fixed to the reinforced concrete specimen, and the reinforcement was pulled out and the maximum load was measured. As shown in Figure 9, the results showed that all of the cone failures occurred not in the joints of the reinforcement materials but in the concrete base material, and it was clear that the reinforcement materials were effectively fixed to the reinforced concrete specimen. The test results of this anchor pull-out test 1 are shown in Table 2 below.

[0053] [Table 2]

[0054] As shown in Table 2, the maximum load for drilling only without treating the drilled hole with unevenness was 330kN, while the maximum load for drilling with unevenness was 464kN, which was higher. From this result, we can see that by performing uneven drilling compared to drilling only, the anchorage force of the reinforcement was resisted over a wider area within the concrete specimen, resulting in a higher maximum load. This is the advantage of uneven drilling.

[0055] [Anchor pull-out test 2] Next, anchor pull-out test 2 conducted to confirm the effect of the present invention will be described. As shown in the photograph in Fig. 8, a circular anchor hole with a diameter of 32 mm and a depth of 400 mm was drilled in a reinforced concrete specimen, and two types of anchor holes with irregularities, No. 1 and No. 2, were prepared by forming two types of anchor holes with irregularities on the inner surface of the hole using the aforementioned recess forming jigs 6 and 6', one with a blade thickness of 10 mm and crescent-shaped (refer also to Fig. 6) recesses (front recess R1 and rear recess R2) with the same pitch of 25 mm only in the front and rear directions as described above, using the aforementioned recess forming jigs 6 and 6'.

[0056] The reason for the blade thickness being set at 10 mm in the developed product is that instead of unevenly processing the entire circumference, the recesses are made thicker to ensure resistance to pulling out. On the other hand, if the blade thickness was made as thick as 10 mm in conventional methods, the construction time would be extremely long and it would be beyond practicality, so the standard blade thickness for conventional methods is 5 mm.

[0057] Then, carbon fiber rods were inserted into these two types of anchor holes as reinforcing materials, solidified with adhesive, and fixed to the reinforced concrete specimen, and the maximum load was measured when the reinforcing materials were pulled out. As shown in Figure 9, the results showed that all of the cone failures occurred not in the joints of the reinforcing materials but in the base material, the concrete, and it was clear that the reinforcing materials were effectively fixed to the reinforced concrete specimen. The results of this anchor pull-out test are shown in the following Table 3 and the load-displacement graph in Figure 10.

[0058] [Table 3]

[0059] As shown in Table 3 and Figure 10, No. 2 (two directions) formed with the recess forming jig 6' of the second embodiment with a blade thickness of 10 mm had a maximum load of 542 kN, while No. 1 (all circumference) had a maximum load of 508 kN. It was found that the anchor hole in which a recess with a blade thickness of 10 mm was formed in only two directions had a higher pull-out resistance than the anchor hole in which a recess was formed all around the circumference.

[0060] Therefore, from the above experimental results, it was proven that according to the present invention, it is possible to reduce construction time by about half, and it is possible to form oval-shaped uneven anchor holes that have better pull-out resistance than anchors formed by drilling holes alone, and that are superior to conventional uneven anchor holes with recesses all around.

[0061] The above describes in detail the oval-shaped uneven anchor hole drilling device 1 according to the embodiment of the present invention and the oval-shaped uneven anchor hole drilling method using the drilling device 1, but the above-mentioned and illustrated embodiments are merely examples of specific embodiments for carrying out the present invention. Therefore, the technical scope of the present invention should not be interpreted in a limited manner based on these.

[0062] In particular, the adhesive that integrates the reinforcing material and concrete in the drilled hole can of course be applied to epoxy resin, cement-based materials, etc., as long as it fills and bonds between the fiber and the concrete. Also, although the reinforcing material has been described as being made of carbon fiber, the present invention is not limited to this, and can be applied to reinforcing materials made of other materials, such as steel bars. [Explanation of symbols]

[0063] 1: Hole drilling device (oval-shaped uneven anchor hole drilling device) 2: Drilling machine body (drilling machine) 20: Cabinet 21: Drive motor (drive means) 22: Rotating shaft (spindle) 23: Coupling 24: Core bit 3: Base plate 31: Height adjustment bolt 4: Guide means 40: Strut 41: Rack 42: Holder 43: Feed handle 5: Forward and backward movement means 6,6': Recess formation jig 60,60': shaft 61,61':Circular blade 62,62': Missing C1: Concrete structure h1: Anchor hole h1': Oval shaped uneven anchor hole R1: Front recess (recess) R2: Rear recess (recess) X1: Forward direction (X direction) X2: Reverse direction (X direction)

Claims

1. An anchor hole drilling device comprising: a drilling machine body having a drive means for rotating a rotary shaft; a base plate for fixing the drilling machine body to a concrete structure; and a guide means provided on the base plate for guiding the drilling machine body in the axial direction of the rotary shaft, a forward / backward movement means for moving the guide means and the drilling machine body forward / backward in one direction perpendicular to the rotation axis, A recess forming jig for simultaneously forming a plurality of recesses on the inner peripheral surface of the drilled anchor hole can be attached to the rotating shaft, the recess forming jig has a shaft body made of a rod material that can be attached to the rotating shaft, and a plurality of circular blades that protrude outward in a disk shape from an outer periphery of the shaft body at predetermined intervals in a longitudinal direction of the shaft body, While the recess forming jig is rotated by the drilling machine body, the guide means and the drilling machine body are moved back and forth by the forward and backward movement means to form an oval-shaped unevenness having recesses in two directions, the recesses being oval in plan view, in the anchor hole. This is an oval-shaped, uneven anchor hole drilling device characterized by the above.

2. The recess forming jig has circular blades formed at predetermined intervals in the longitudinal direction of the shaft body over a necessary fixing length of the anchor hole or more.

2. The oval-shaped uneven anchor hole drilling device according to claim 1 .

3. A method for drilling an oval-shaped uneven anchor hole, which uses the oval-shaped uneven anchor hole drilling device according to claim 1 or 2 to drill an oval-shaped uneven anchor hole having an oval shape in plan view, An anchor hole drilling step of drilling an anchor hole by attaching a core bit to the rotating shaft; a jig replacement process of mounting the recess forming jig on the rotating shaft in place of the core bit without removing the base plate from the concrete structure; a recess forming step of inserting the recess forming jig into the anchor hole drilled in the anchor hole drilling step, and moving the guide means and the drilling machine body forward and backward with the forward and backward moving means while rotating and driving the recess forming jig with the drilling machine body, thereby forming an oval-shaped unevenness having recesses in two directions in front and rear on the inner peripheral surface of the anchor hole, the oval-shaped unevenness having an oval shape in a plan view; A method for drilling oval embossed anchor holes.

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