JP6516631B2 - Mounting method and mounting structure of embedded bolt - Google Patents

Description

  The present invention relates to a mounting method and a mounting structure of an embedding bolt for embedding and fixing a support bolt to a concrete layer.

  When a bolt is fixed to a concrete layer, for example, a lining concrete layer of a tunnel, an expanded shaft type anchor bolt provided with a split groove at the tip is punched into the concrete layer (for example, Patent Document 1), embedded in the lining concrete layer It is common practice to screw the proximal end of the anchor pin with the adhesive applied to the insert having the internal thread cut (for example, Patent Document 2).

Tokoku 8-19833 Patent No. 3801013

  However, the method of driving the anchor bolt into the lining concrete layer in this way and fixing it by expanding the split groove at its tip, or the method of fixing the bolt to the embedded insert by means of the adhesive filler and screwing, It has been difficult to keep the bolt fixing strength high for a long time. In particular, in an environment where vibration is applied to the fixed part, or where there is a lot of moisture and moisture, this tendency is large.

  Therefore, an object of the present invention is to provide a mounting method and a mounting structure for an embedded bolt which can reliably maintain high fixed strength over a long period without depending on the environment.

  According to the present invention, the method of attaching the embedding bolt comprises: drilling a first non-penetrating hole and a second non-penetrating hole smaller in diameter than the first non-penetrating hole in the concrete layer to which the embedding bolt is to be installed A step having a width substantially equal to the diameter of the second non-through hole, and bringing the second non-through hole and the first non-through hole into communication with each other over substantially the entire length of the second non-through hole; Forming a lateral communication passage, and having a width substantially equal to or slightly larger than the diameter of the first non-through hole, and only in a predetermined depth range of the second non-through hole. Forming a second lateral communication passage for causing the non-through hole and the first non-through hole to communicate with each other, and a diameter smaller than the diameter of the first non-through hole and larger than the diameter of the second non-through hole A head of an embedded bolt having a head of the second part and a shaft of a smaller diameter than the diameter of the second non-through hole, Installing the embedded bolt in the second non-through hole by inserting into the one non-through hole and moving the inside of the first lateral communication passage and the second lateral communication passage to the second non-through hole And filling the filling material in a space between the first non-through hole, the second non-through hole, the first lateral communication passage, and the second lateral communication passage and the embedded bolt. .

  The first non-through hole, the second non-through hole, the first lateral communication passage and the second lateral communication passage are formed in the concrete layer, and the second non-through hole is smaller than the diameter of the first non-through hole. Insert this head of the embedded bolt having a head with a diameter larger than the diameter of the through hole and a stem with a diameter smaller than the diameter of the second non-through hole into the first non-through hole, and The embedded bolt is moved into the second non-through hole by moving the direction communication path and the second lateral communication path to the second non-through hole, and then the first non-through hole, the second non-through hole, and the second non-through hole. A filler is filled in the through hole, the first lateral communication passage, and the gap between the second lateral communication passage and the embedded bolt. As a result, the embedded bolt is supported by the concrete layer near the second non-through hole whose head is present on the surface side of the second lateral communication passage. Accordingly, the pull-out strength of the embedded bolt has a high value corresponding to the thickness of the concrete layer in this portion, and is maintained over a long period of time regardless of the environment. As a result, under all circumstances, the fixing strength of the embedded bolt can be more reliably maintained over a long period of time.

  It is also preferable that the step of drilling includes the step of drilling the depth of the first non-through hole deeper than the depth of the second non-through hole.

  The step of drilling is a step of drilling a first non-through hole in the concrete layer, a step of drilling a second non-through hole in the concrete layer, a first non-through hole and a second non-through hole A non-through hole having a diameter substantially the same as the diameter of the second non-through hole is bored between the holes and the first non-through hole and the second non-through hole communicate with each other to form a first lateral communication passage It is also preferable to include the forming step.

  In this case, it is preferable that the step of forming the first lateral communication passage be performed using a positioning jig that positions the first non-through hole in a hole separated by a predetermined distance.

  In the step of forming the second lateral communication passage, a predetermined depth of the concrete layer is formed by using a sander drill equipped with a rotary blade having an outer diameter approximately equal to or slightly larger than the diameter of the first non-through hole. It is also preferable to include the step of forming the second lateral communication passage by grinding in the direction of the second non-through hole from the first non-through hole in the length range.

  It is also preferable that the step of forming the second lateral communication passage is performed using a depth determination jig which depths the sander drill to a predetermined depth of the concrete layer.

  It is also preferable that the step of filling the filler is a step of using non-shrink mortar or lightweight mortar as the filler.

  According to the present invention, the mounting structure of the embedded bolt is formed in the concrete layer to be installed the embedded bolt, and the first non-through hole having a diameter larger than the diameter of the head of the embedded bolt and the concrete layer A second non-through hole having a diameter smaller than the diameter of the head of the embedded bolt and larger than the diameter of the shank of the embedded bolt, and having a width substantially equal to the diameter of the second non-through hole, A first lateral communication passage for causing the second non-through hole and the first non-through hole to communicate with each other over substantially the entire length of the two non-through holes, and the diameter of the first non-through hole A second lateral communication passage having a large width and communicating the second non-through hole and the first non-through hole with each other only in a predetermined depth range of the second non-through hole; And the head of the embedded bolt is the second side of the second non-through hole A gap between the first non-through hole, the second non-through hole, the first lateral communication passage and the second lateral communication passage, and the embedded bolt, which is configured to be disposed in the communication passage. Is filled with filler.

  It is also preferred that the first non-through hole is deeper than the depth of the second non-through hole.

  It is also preferred that the filler be non-shrink mortar or lightweight mortar.

  According to the present invention, the embedded bolt is supported by the concrete layer near the second non-through hole whose head exists on the surface side of the second lateral communication passage, and the pull-out strength of this embedded bolt Is a high value according to the thickness of the concrete layer in this part, and is maintained over a long period of time regardless of the environment. As a result, under all circumstances, the fixing strength of the embedded bolt can be more reliably maintained over a long period of time.

It is a perspective view which shows roughly the attachment structure of the embedding bolt to a concrete layer as one Embodiment of this invention. It is a top view which shows roughly the attachment structure of the embedding bolt to the concrete layer in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. It is sectional drawing which shows the BB line cross section of FIG. It is a side view which shows roughly an example of the embedding bolt in the embodiment of FIG. It is a flowchart explaining the rough construction process in the embodiment of FIG. It is a perspective view which shows an example of the jig | tool for black out used by the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is a perspective view which shows an example of the positioning jig used at the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is a perspective view which shows an example of the jig for depth determination used at the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG. It is sectional drawing which shows the AA line cross section of FIG. 2 for demonstrating the construction process in embodiment of FIG.

  FIG. 1 schematically shows the attachment structure of the embedded bolt to the concrete layer as one embodiment of the present invention, FIG. 2 schematically shows the embedded bolt attachment structure of the present embodiment, and FIG. The AA line cross section of FIG. 2 is shown, FIG. 4 shows the BB line cross section of FIG. 2, and FIG. 5 has shown schematically an example of the embedding bolt in this embodiment.

  The present embodiment relates to, but is not limited to, a structure in which embedded bolts are attached to a lining concrete layer provided, for example, on the ceiling or side wall of an automobile or railway tunnel. This embedded bolt is used in this embodiment to suspend or attach structures such as various signs, jet fans, signals, or overhead wires to the lining concrete layer.

  In FIG. 1 and FIG. 2, 10 is a lining concrete layer, 11 is a keyhole-like hole drilled in this lining concrete layer 10, 12 is an embedding bolt fixed to this keyhole-like hole 11, 13 is an embedding bolt 12 A washer 14 is passed through, a nut 14 screwed to the embedded bolt 12, and a filler 15 filled in the keyhole 11 respectively. However, in FIG. 2, in order to clearly show the shape of the keyhole-like hole 11, the indication of the washer 13 and the nut 14 is omitted.

  As shown in FIGS. 2 to 4, the keyhole-shaped hole 11 includes a first non-through hole (bolt insertion hole) 16, a second non-through hole (bolt installation hole) 17, and a first lateral run. It is mainly composed of the passage 18 and the second lateral communication passage 19.

The first non-through hole 16 is a non-through hole drilled to a predetermined depth (for example, about 80 mm, for example only) from the surface of the lining concrete layer 10, and the head of the embedded bolt 12 It has a larger diameter phi ₁ than the diameter of 12a. The second non-through hole 17 is a non-through hole drilled from the surface of the lining concrete layer 10 to a predetermined depth (for example, about 70 mm as an example only), and the first non-through hole 16 smaller than the diameter phi ₁ of and has a larger diameter phi ₂ than the diameter of the shaft portion 12b of the stud 12. The depth of the first non-through hole 16 is slightly deeper (about 10 mm in the above-mentioned example) than the depth of the second non-through hole 17 (and the second lateral communication passage 20). This is because the bottom 16a (see FIGS. 3 and 4) of the first non-through hole 16 has unevenness due to the aggregate contained in the concrete when the first non-through hole 16 is drilled, This is to adjust the depth with the second non-through hole 17 and the second lateral communication passage 19. By forming such unevenness on the bottom 16 a of the first non-through hole 16, the filler 15 can enter between the unevenness and increase the adhesive strength.

As the embedded bolt 12, those of various shapes and sizes can be used. In this embodiment, as one example, as shown in FIG. 5, M12 × 130 provided with a circular head 12a is used. Of course, the shape of the head 12a may be various shapes other than a circular shape such as a hexagonal shape, and various dimensions can be applied. As in the present embodiment, when using M12 × 130, the diameter of the head 12a is about 30 mm, the thickness is about 5 mm, and the diameter of the shaft 12b is about 12 mm. In this case, the diameter phi ₁ of the first non-through hole 16 is 32 mm, the diameter phi ₂ of the second non-through hole 17 is about 14 mm.

The first lateral communication passage 18 has a width W ₁ substantially equal to (or slightly larger than) the diameter φ ₂ of the second non-through hole 17 and extends substantially the entire length of the second non-through hole 17. The two non-through holes 17 and the first non-through holes 16 communicate with each other. The second lateral communication passage 19 has a width W ₂ substantially equal to (or slightly larger than) the diameter φ ₁ of the first non-through hole 16 and has a predetermined depth from the surface of the lining concrete layer 10 (merely This is an example, for example, at a predetermined depth downward from the position of about 70 mm (for example, about 6 mm when the embedded bolt 12 has a thickness of about 5 mm as described above. The two non-through holes 17 and the first non-through holes 16 communicate with each other. That is, the second lateral communication passage 19 is provided in the depth range of about 64 to about 70 mm in this case.

  The embedded bolt 12 is installed in the second non-through hole 17 so that the end portion thereof protrudes to the outside of the lining concrete layer 10. In that case, the head 12 a of the embedded bolt 12 is installed so as to be located in the second non-through hole 17 and the second lateral communication passage 19.

  In the gaps between the first non-through hole 16, the second non-through hole 17, the first lateral communication passage 18 and the second lateral communication passage 19, and the embedded bolt 12, as shown in FIGS. As shown, a filler 15 such as non-shrink mortar or lightweight mortar is filled. Instead of such a filler, for example, a resin adhesive having viscosity, such as an epoxy resin or an acrylic resin, or another adhesive filler having adhesiveness may be filled.

  The diameter or width and depth of the first non-through hole 16, the second non-through hole 17, the first lateral communication passage 18 and the second lateral communication passage 19 are the same as the dimensions of the embedded bolt 12. It is decided according to. Although M12 × 130 is used as the embedded bolt 12 in the present embodiment, other length M12 may be used, or an embedded bolt of M14 or M16 may be used. However, since the diameter of the second non-through hole 17 is smaller if the embedded bolt has a diameter as small as possible within the allowable range of the load, the load area is reduced, and the lining concrete layer 10 is used. The effect of the load on the In addition, to the lining concrete layer 10, the smaller diameter or width of the first non-through hole 16, the second non-through hole 17, the first lateral communication passage 18 and the second lateral communication passage 19 is used. Not only is the influence of the load small, but also the size of the processing tool becomes smaller and the processing time becomes shorter.

  Hereinafter, the construction procedure in the present embodiment will be described in detail with reference to FIGS.

  First, on the surface of the lining concrete layer 10, the drilling positions of the first non-through hole (bolt insertion hole) 16 and the second non-through hole (bolt installation hole) 17 determined by confirming the arrangement position Are put out (step S1). It is efficient to use an inking jig 20 as shown in FIG. 7 for this inking. The inking jig 20 is a transparent plastic plate, on one surface of which vertical and horizontal reference lines 20a and 20b for defining the drilling positions of the second non-through holes 17 are described. A through hole 21 corresponding to the first non-through hole 16, the second non-through hole 17 and the first lateral communication passage 18 is formed. The marking jig 20 is placed on the lining concrete layer 10 on the basis of the drilling position of the second non-through hole 17 on the surface of the lining concrete layer 10, and the black color is drawn along the outline of the through hole 21. Take out.

  Next, the lining concrete layer 10 is vertically drilled using a core drill which is fixed by suction to the surface of the lining concrete layer 10, and a first non-through hole 16 is drilled (step S2). The first non-through hole 16 is drilled to a depth of about 80 mm in the present embodiment, and a cylindrical concrete piece corresponding to the drilled hole is applied by applying a lateral load to the drilled portion. obtain. FIG. 8 shows a state in which the first non-through hole 16 is drilled using a core drill, and FIG. 9 shows the first non-through hole 16 in a state in which a column-shaped concrete piece left by drilling is removed. It shows.

  Next, the lining concrete layer 10 is drilled using a core drill or a hammer drill or the like, and a second non-through hole 17 is drilled (step S3). The second non-through hole 17 is drilled so as to be about 10 mm shallower than the first non-through hole 16 and to have a depth of about 70 mm. FIG. 10 shows a state in which the second non-through hole 17 is formed.

Next, a core drill or a hammer drill or the like is used to drill a hole between the first non-through hole 16 and the second non-through hole 17 of the lining concrete layer 10, and the diameter is continued to the second non-through hole 17 bored substantially non-through hole of the same diameter as phi _2. The depth of this non-through hole is about 70 mm, which is the same as the second non-through hole 17. In this case, it is desirable to use a positioning jig 22 made of metal (for example, steel) as shown in FIG. 11 for defining the drilling position of the non-through hole. The positioning jig 22 has a cruciform projection 23 as a reference and a through hole 24a or 24b with a cylinder for inserting a drill. By inserting the cruciform projection 23 into the first non-through hole 16 and inserting the drill from the back side of FIG. 11 and drilling at that position, the non-through hole is easily formed at the desired position. By providing such a non-through hole, a first lateral run connecting the second non-through hole 17 and the first non-through hole 16 with each other over the entire length of the second non-through hole 17. The passage 18 is formed (step S4). The width W ₁ of the first lateral communication passage 18 is approximately equal to (or slightly larger than) the diameter φ _{2 of} the second non-through hole 17. FIG. 12 shows the state in which the first lateral communication passage 18 is formed.

Then, using a sander drill equipped with a special rotary blade at the tip of the rotary shaft, the first non-through hole 16 in a predetermined depth range (depth range of about 64 to about 70 mm) of the lining concrete layer 10 The second transverse communication passage 19 is formed by grinding in the direction of the second non-through hole 17 (step S5). In order to form the second lateral communication passage 19 parallel to the surface of the lining concrete layer 10, the depth of metal (for example, steel) is determined as shown in FIG. 13 for translating the sander drill. It is desirable to use a jig 25. The depth determining jig 25 has drill mounting portions 26 and 27 on which the main body of the sander drill is mounted, and has a sliding surface on the back side in FIG. The main body of the sander drill is placed on the drill mounting portions 26 and 27, the rotary shaft and the rotary blade are inserted into the first non-through hole 16, and the sliding surface is slid on the surface of the lining concrete layer 10 Thus, the rotary blade can be easily translated along the surface of the lining concrete layer 10 at a predetermined depth. FIG. 14 shows a state in which the second lateral communication passage 19 is formed. The sander drill used has a rotary shaft longer than usual, and the rotary blade mounted at its tip has an outer diameter approximately equal to or slightly larger than the diameter φ ₁ of the first non-through hole 16 And a predetermined thickness. Thereby, the width of the second lateral communication passage 19 to be formed is approximately equal to or slightly larger than the diameter φ ₁ of the first non-through hole 16, and the height thereof corresponds to the thickness of the rotary blade (see FIG. For example, about 6 mm).

  Next, the embedded bolt 12 is installed in the second non-through hole 17 (step S6). In this installation, as shown in FIG. 15, the head 12a of the embedded bolt 12 is inserted into the first non-through hole 16 and the inside of the first lateral communication passage 18 and the second lateral communication passage 19 is It is performed by moving to the second non-through hole 17. FIG. 16 shows this state.

  Thereafter, as shown in FIG. 17, the filling material 16 such as non-shrink mortar or light weight mortar, for example, is used as the first non-through hole 16, the second non-through hole 17, the first lateral communication passage 18 and the second Further, filling is performed so that no air gap is generated between the embedded bolt 12 and all the holes and passages including the lateral communication passage 19 (step S7). This filling is done using a grease gun, a spatula and / or a trowel. In addition, it is desirable to cure the embedded bolt 12 with a vinyl tape etc. in the part exposed from the surface of the lining concrete layer 10, for example.

  Thereafter, the nut 14 is screwed to the embedded bolt 12 via the washer 13 to firmly fix the embedded bolt 12. This state is shown in FIGS. 3 and 4.

  After the filler 15 hardens, the structure is attached to the embedded bolt 12.

  As described above, according to the present embodiment, not only the filler 15 but also the second non-through hole in which the head 12 a of the embedded bolt 12 exists on the surface side of the second lateral communication passage 20. It will be supported by the lining concrete layer 10 near 17. Therefore, the pull-out strength of the embedded bolt 12 becomes a high value corresponding to the thickness of the lining concrete layer 10 in this portion, and the pull-out strength is maintained over a long period of time without being influenced by the environment. As a result, the fixed strength of the embedded bolt 12 can be more reliably maintained over a long period of time under any environment where vibration or moisture is applied.

  Hereinafter, a bolt pullout test of the mounting structure of the embedded bolt of the present invention will be described.

Table 1 shows the results of the bolt pullout test conducted on October 8, 2014 at the Tokyo Metropolitan Industrial Technology Research Center Demonstration Center. This test uses embedded bolts (M12, SUS304, head diameter 30 mm, head thickness 5 mm, shaft length 130 mm), the head of the embedded bolt is 450 mm × 450 mm × 200 mm, compressive strength 21 N / mm. ^The maximum value for those placed in the second non-through hole formed in the concrete specimen of 2 and filled with shrink mortar in the first non-through hole and second non-through hole and those not filled with the shrink mortar The tensile load value was measured. The number of samples is three for each sample. In the central part of the concrete test body, a first non-through hole with a large diameter of 32 mm, and a second non-through hole with a small diameter of 14 mm communicating with this (the distance 40 mm between both holes) are formed . As a testing machine, a 500 kN class universal tensile tester (AG-500 kN Xplus) manufactured by Shimadzu Corporation was used (maximum load: 500 kN, tensile displacement: 1160 mm, maximum test speed: 50 mm / min).

  As a test method, fix the concrete test body with the embedded bolt installed on the test stand of the testing machine, start the measurement by pinching the screw part of the embedded bolt with the chuck of the tensile tester, or the concrete test body is broken Or, the test is ended when the embedded bolt breaks and the maximum tensile load value is measured.

  Samples 1-1 to 1-7 are shown in Table 1 in the case where the shrink mortar is filled in the second non-through hole and the first non-through hole in which the embedding bolt is installed. If the shrink mortar is not filled in the second non-through hole and the first non-through hole in which the embedding bolt is installed, the head of the embedding bolt may be deformed at a tensile load value much lower than Table 1, or Internal collapse of the non-through hole occurred. As can be seen from Table 1, in Samples 1-1 to 1-7, which are examples of the present invention, sufficiently excellent maximum tensile load values are obtained.

  The embodiments and examples described above are all illustrative of the present invention and not limiting, and the present invention can be practiced in various other variations and modifications. Accordingly, the scope of the present invention is to be defined only by the appended claims and their equivalents.

DESCRIPTION OF SYMBOLS 10 lining concrete layer 11 keyhole-like hole 12 embedded bolt 12a head 12b axial part 13 washer 14 nut 15 filler 16 1st non-through hole (bolt insertion hole)
16a bottom 17 second non-through hole (bolt mounting hole)
18 first lateral communication passage 19 second lateral communication passage 20 jig for marking 20a, 20b reference line 21 through hole 22 positioning jig 23 cruciform protrusion 24a, 24b through hole with cylinder portion 25 deep Jigs for determining the size 26, 27 Drill mounting portion

Claims (10)

  Drilling a first non-through hole and a second non-through hole having a diameter smaller than that of the first non-through hole in the concrete layer in which the embedding bolt is to be installed; Forming a first lateral communication passage having substantially the same width and connecting the second non-through hole and the first non-through hole to each other over substantially the entire length of the second non-through hole; And a width substantially equal to or slightly larger than the diameter of the first non-through hole, and the second non-through hole and the first non-through hole only in a predetermined depth range of the second non-through hole. Forming a second lateral communication passage communicating the non-through holes with each other, and a head having a diameter smaller than the diameter of the first non-through holes and larger than the diameter of the second non-through holes, and The head portion of the embedded bolt having a shaft portion having a diameter smaller than the diameter of the second non-through hole; The embedded bolt is installed in the second non-through hole by inserting the through hole and moving the inside of the first lateral communication passage and the second lateral communication passage to the second non-through hole. And filling the filling material in a space between the first non-through hole, the second non-through hole, the first lateral communication passage, and the second lateral communication passage and the embedded bolt. And mounting the embedded bolt.   The embedded bolt according to claim 1, wherein the step of drilling includes the step of drilling the depth of the first non-through hole deeper than the depth of the second non-through hole. Mounting method.   The drilling step is a step of drilling the first non-through hole in the concrete layer, a step of drilling the second non-through hole in the concrete layer, and the first non-through hole And a non-through hole having a diameter substantially the same as the diameter of the second non-through hole between the second non-through holes to communicate the first non-through hole and the second non-through hole with each other And forming the first lateral communication passage. The method for attaching the embedded bolt according to claim 1 or 2, further comprising:   The step of forming the first lateral communication passage is performed using a positioning jig which is positioned at a predetermined distance away from the drilled first non-through hole. The mounting method of the embedding bolt as described in 3.   In the step of forming the second lateral communication passage, the concrete layer is formed using a sander drill equipped with a rotary blade having an outer diameter approximately equal to or slightly larger than the diameter of the first non-through hole. Forming a second lateral communication path by grinding in a direction from the first non-penetrating hole to the second non-penetrating hole in a predetermined depth range of The mounting method of the embedding bolt of any one of 1-4.   6. The method according to claim 5, wherein the step of forming the second lateral communication path is performed using a depth setting jig for setting the sander drill to a predetermined depth of the concrete layer. How to install the embedded bolt of the.   The method of attaching the embedded bolt according to any one of claims 1 to 6, wherein the step of filling the filler is a step of using a non-shrink mortar or a lightweight mortar as the filler.   And a first non-through hole having a diameter larger than the diameter of the head of the embedded bolt and drilled in the concrete layer, the embedded bolt being drilled in the concrete layer to be installed; A second non-through hole having a diameter smaller than the diameter and larger than the diameter of the shaft portion of the embedded bolt; and a width substantially equal to the diameter of the second non-through hole, the second non-through hole A first lateral communication passage for connecting the second non-through hole and the first non-through hole to each other over substantially the entire length, and a width substantially equal to or slightly larger than the diameter of the first non-through hole And having a second lateral communication passage that allows the second non-through hole and the first non-through hole to communicate with each other only in a predetermined depth range of the second non-through hole. And the head of the embedded bolt is the second non-through hole The first non-through hole, the second non-through hole, the first lateral communication passage, and the second one are configured to be disposed in the second lateral communication passage. A filler is filled in a gap between a lateral communication passage and the embedding bolt, and the mounting structure of the embedding bolt.   The mounting structure of the embedded bolt according to claim 8, wherein the first non-through hole is deeper than the depth of the second non-through hole.   The mounting structure of the embedded bolt according to claim 8 or 9, wherein the filler is a non-shrink mortar or a lightweight mortar.

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