JP3867743B2 - Reinforcement method of rock bolt - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for reinforcing a rock bolt used for, for example, a slope stabilization method.
[0002]
[Prior art]
Conventionally, in order to increase the strength in the lock bolt method such as the slope stabilization method, for example, (1) increase the number of lock bolts, (2) use a large diameter lock bolt, (3) high strength lock There are methods such as using bolts.
[0003]
[Problems to be Solved by the Invention]
By the way, these methods have problems in cost and workability. In particular, the anchor bolts used for the lock net are those that drill holes in the ground, insert the lock bolts, fill the grout material, and then attach the wire that fixes the lock net, but when a load is applied to the wire In addition, the pull-out strength is sufficient, but when stress is applied, such as bending tension or shearing force, the strength is insufficient, and the lock bolt may be deformed or broken by bending or shearing force. May lead to the collapse of. In addition, when a large-diameter lock bolt is used, deformation and breakage can be suppressed, but there is a problem in workability due to its heavy weight.
[0004]
The present invention has been made in view of this point, and an object of the present invention is to provide a method for reinforcing a rock bolt that can overcome the above-described problems and can reinforce a lock bolt easily and economically.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems and achieve the object, the invention according to claim 1 is as follows: `` The grout material is filled between the rock bolt and the hole inserted into the hole drilled in the natural ground,
Set to a predetermined position of the Rokkuboru Bok in the reinforcing pipe extrapolated hole,
When the grout material is hardened, attach a pulling member fixture to the tip of the reinforcing pipe protruding from the ground,
The distal end portion of the reinforcing pipe from the tip portion protruding from the natural ground of the Rokkuboru Bok, insert the presser jig for restricting the exit of the tension member attachment,
A nut was screwed onto the tip of the lock bolt and the tension member fixture was pressed and fixed via the presser jig .
A method of reinforcing a rockbol cage characterized by the above. Since the reinforcing pipe is inserted into the lock bolt to a predetermined position in the hole, the shearing force is improved, and it is possible to prevent the lock bolt from being deformed or broken by the bending or shearing force of the lock bolt. In addition, the tension member can be securely attached by the tension member mounting tool, and the lifting of the tension member mounting tool can be prevented by the holding jig. Furthermore, since the lock bolt can be easily reinforced using a conventional lock bolt, it is economical.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method for reinforcing a rock bolt according to the present invention will be described below with reference to the drawings. First, FIG. 1 to FIG. 3 show a first embodiment of a method for reinforcing a lock bolt, FIG. 1 is a diagram showing a method for reinforcing a lock bolt, FIG. 2 is a diagram showing a reinforcing pipe, and FIG. 3 is a holding jig. FIG.
[0007]
The grout material 3 is injected and filled into the hole 2 drilled in the ground 1 and the rock bolt 4 is inserted. The injection time of the grout material 3 may be after the rock bolt 4 is inserted.
[0008]
Before the grout material 3 is cured, the reinforcing pipe 6 as a reinforcing member is inserted into the lock bolt 4 through the square washer 5 to a predetermined position in the hole 2. As shown in FIGS. 1 and 2, the reinforcing pipe 6 is provided with a stopper portion 6 a, and the insertion position is determined by pushing the reinforcing pipe 6 and the stopper portion 6 a abutting against the square washer 5. The shape of the stopper portion 6a is not particularly limited as long as the stopper 6a is caught on the square washer 5 when the reinforcing pipe 6 is pushed.
[0009]
As a result, the grout material 3 is filled in the gap between the reinforcing pipe 6 and the lock bolt 4. When the grout material 3 is sufficiently cured, the tension member attaching tool 7 is attached to the tip of the reinforcing pipe 6 protruding from the natural ground 1. Then, a holding jig 8 is inserted into the distal end portion of the reinforcing pipe 6 to prevent the pulling member attachment 7 from coming off, and a nut 9 is screwed and fixed to the distal end portion of the lock bolt 4.
[0010]
In this way, the tension member attaching tool 7 is attached to the distal end portion of the reinforcing pipe 6 inserted into the lock bolt 4. The holding jig 8 has a stopper portion 8 a that prevents the pulling member attachment 7 from coming out on one side and a washer portion 8 b that receives the tightening load of the nut 9 on the other side. And prevent it from coming out. The height H of the holding jig 8 is a height at which the washer portion 8b does not contact the tip of the reinforcing pipe 6 when the nut 9 is screwed as shown in FIG. Thereby, the holding jig 8 can hold down the pulling member attachment 7 reliably.
[0011]
Note that the holding jig 8 is not limited to the one shown in FIG. 3, and may be a flat plate having a predetermined thickness as long as it can press the pulling member attachment 7. Further, the lock bolt 4 to be used may be an all-screw type or a bolt that can be screwed onto the nut 9 by screwing the bolt end. Furthermore, a self-drilling type rockbol can be used. Further, in this embodiment, the stopper portion 6a is provided integrally with the reinforcing pipe 6, but a flat plate or the like may be welded.
[0012]
Further, the reinforcing pipe 6 may be inserted before the square washer 5. In this case, the stopper portion 6 a is positioned in contact with the ground 1, and then the square washer 5 is inserted to attach the pulling member fixture 7. .
[0013]
As described above, since the reinforcing pipe 6 is inserted into the lock bolt 4 to a predetermined position in the hole 2, the shearing force is improved, and the lock bolt 4 is deformed or broken by the bending or shearing force due to the pulling from the pulling member attachment 7. Can be prevented. Further, the tension member can be securely attached by the tension member attaching tool 7, and the lifting member 8 can be prevented from being lifted by the presser jig 8.
[0014]
Further, since the reinforcement can be easily performed by simply attaching the reinforcement pipe 6 to the rockbolt 4, the workability is good. Further, the use of the reinforcing pipe 6 makes it possible to reinforce the lock bolt 4 with a minimum hole diameter, and it is economical because the lock bolt 4 can be easily reinforced using the conventional lock bolt 4. .
[0015]
Moreover, it can respond to various natural grounds by changing the embedding depth of the reinforcement pipe 6.
[0016]
Next, FIG. 4 shows a second embodiment of the method for reinforcing the rock bolt. The method of reinforcing the lock bolt is configured in the same manner as in FIG. 1, but shows a modification of the reinforcing member, in which a sleeve 16 having a stopper portion 16 a is pressure-bonded to the lock bolt 4. In this case, since there is no gap between the lock bolt 4 and the sleeve 16, the diameter can be made smaller than that of the reinforcing pipe 6, and the workability is good because it is only inserted into the drilled hole 2. In this embodiment, since the sleeve 16 is pressure-bonded to the lock bolt 4, the stopper portion 16a is not necessary.
[0017]
Next, a description will be given of a slope stabilizing method in which the method for reinforcing the rock bolt is used. 5 is a view showing a state in which the lock cover net is supported, FIG. 6 is a view showing a tension member mounting tool, FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6, and FIG. .
[0018]
The lock cover net 60 used in the slope stabilization method is to prevent falling rocks and the like, and wire ropes 61 and 62 are attached to the lock cover net 60 with wires or the like at predetermined intervals in the vertical and horizontal directions. Each wire rope 61, 62 is fixed to the lock bolt 4 via the tension member attachment 7 at both ends. As shown in FIGS. 6 to 8, the tension member fitting 7 has a shock-absorbing metal fitting 70 and a U-bolt 71. The shock-absorbing metal fitting 70 sandwiches the wire ropes 61 and 62 between a pair of metal fittings 72 and 73, The nut 75 is fastened and fixed. The U-bolt 71 is attached to the shock-absorbing metal fitting 70 by inserting both ends 71a thereof into the boss parts 72a and 73a of the pair of metal fittings 72 and 73 and screwing nuts 76 to screw parts 71b protruding from the boss parts 72a and 73a. It is done. In this way, the bent portion 71c of the U bolt 71 attached to the buffer metal fitting 70 is attached to the reinforcing member of the lock bolt 4, the nut 76 is rotated to pull the wire ropes 61 and 62, and the lock cover net 60 is stretched. Prevents rockfalls from occurring.
[0019]
FIG. 9 is a view showing another embodiment for supporting the lock cover net. In this embodiment, the tension member mounting tool 7 is configured in the same manner as the embodiment shown in FIGS. 6 to 8, but one wire rope 80 is vertically attached to the lock cover net 60 in the vertical direction at a predetermined interval. Turn and attach with wire etc. Similarly, turn one wire rope 81 on the lock cover net 60 at a predetermined interval in the horizontal direction and attach with wire etc. Pull the turn part of each wire rope 80, 81 The lock cover net 60 is supported by the member fixture 7 and the occurrence of falling rocks is prevented.
[0020]
[Effect of the invention]
As described above, according to the present invention, since the reinforcement pipe is provided to the predetermined position in the hole in the lock bolt, the shearing force is improved, and the lock bolt is prevented from being deformed or broken by the bending or shearing force of the lock bolt. Can do. In addition, the tension member can be securely attached by the tension member mounting tool, and the lifting of the tension member mounting tool can be prevented by the holding jig. In addition, the workability is good because it can be easily reinforced simply by attaching a reinforcing member to the rockbolt. Further, since the lock bolt can be reinforced with the minimum hole diameter by using the reinforcing member, the lock bolt can be easily reinforced using the conventional lock bolt, which is economical.
[Brief description of the drawings]
FIG. 1 is a view showing a method for reinforcing a rock bolt.
FIG. 2 is a view showing a reinforcing pipe.
FIG. 3 is a view showing a holding jig.
FIG. 4 is a diagram showing a second embodiment of a method for reinforcing a rock bolt.
FIG. 5 is a diagram showing a state in which a lock cover net is supported.
FIG. 6 is a view showing a tension member mounting tool.
7 is a cross-sectional view taken along line VII-VII in FIG.
FIG. 8 is a plan view of a U-bolt.
FIG. 9 is a view showing another embodiment for supporting the lock cover net.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ground 2 Hole 3 Grout material 4 Rockbolt 7 Tensile member fixture 8 Pressing jig 9 Nut

Claims (1)

The grout material is filled between the rock bolt and the hole inserted in the hole drilled in the ground,
Set to a predetermined position of the Rokkuboru Bok in the reinforcing pipe extrapolated hole,
When the grout material is hardened, attach a pulling member fixture to the tip of the reinforcing pipe protruding from the ground,
The distal end portion of the reinforcing pipe from the tip portion protruding from the natural ground of the Rokkuboru Bok, insert the presser jig for restricting the exit of the tension member attachment,
A nut was screwed onto the tip of the lock bolt and the tension member fixture was pressed and fixed via the presser jig .
A method of reinforcing a rockbol cage characterized by the above.

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