JPH0439358Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a rock bolt used for rock consolidation, which improves soft or fractured rock into a solid rock using a rock consolidation chemical.

[Conventional technology]

In tunnel construction, etc., in order to prevent rockfalls that occur at faces where the rock (ground) is soft, a rock consolidation method is used in which a chemical solution for rock consolidation with high consolidation strength is injected into the ground. . This method is the 14th
As shown in the figure, on the top plate part 34 at the tip of the tunnel face,
A hole 35 is drilled in advance with a rock drill or the like, and a hollow pipe-shaped lock bolt 37 with a sealing material 36 provided at its base is inserted into the hole 35, and the opening of the hole 35 is closed with the sealing material 36. . Then, in this state, the hose 33 is connected to the root side end 37a of the lock bolt 37 via the connection unit 32, and the two-component foamed urethane resin is press-fitted from the press-fitting device 38 into the lock bolt 37 and the opening at the tip thereof is inserted. The holes 35 are filled with urethane resin by discharging it from the pores, and the urethane resin is further infiltrated into the ground and hardened to solidify the ground.

[Problem that the invention attempts to solve]

However, the rock bolt used in the above method is simply inserted into a drilled hole and does not have the ability to drill the hole itself. It is necessary to drill a hole and insert a lock bolt into the hole. However, doing so requires the steps of drilling a hole with a rock drill, pulling the drill out of the hole, and inserting a lock bolt, which makes the consolidation work complicated. Also,
As mentioned above, the lock bolt is for hole insertion and does not have a sharp tip, so the hole needs to be large enough to insert the lock bolt, which takes time and effort. It had harmful effects. Moreover, in the above-mentioned lock bolt, a stationary mixer 39 with mixing blades for mixing and stirring two liquids of urethane resin is inserted through the tip opening of the lock bolt 37, and its base is fixed with a socket 40 which becomes a discharge nozzle. Because
The urethane resin liquid mixed and stirred by the static mixer 39 is discharged in a non-uniform turbulent flow from the discharge nozzle socket 40 and a plurality of discharge holes provided on the outer periphery of the vicinity thereof. The turbulent urethane resin liquid is not uniformly discharged from the discharge nozzle socket 40 and discharge hole, and as a result, the solidified area formed around the lock bolt 37 is disturbed.
The problem was that the finish was not uniform. Furthermore, in order to fix the static mixer to the tip of the lock bolt, members such as sockets are required, resulting in the problem of an increase in the number of members.

This invention was devised in view of these circumstances, and its purpose is to provide a lock bolt that can simplify construction work and achieve uniform rock solidification.

[Means for solving problems]

In order to achieve the above object, the lock bolt of this invention consists of a packer part consisting of a hollow pipe with a closed end, a stationary mixer with mixing blades attached to the packer part, a lockbolt main body made of a hollow pipe, and the packer part made of a hollow pipe with a closed end. The packer part is provided with a bit part at the tip part, a discharge hole is bored in the bit part, and the inner wall of the rear end of the hollow part is provided with a pipe joint that connects the rear end of the part and the tip of the lock bolt body. A stationary mixer attachment part is provided, the stationary mixer is attached to the stationary mixer attachment part, and the pipe joint has joint parts on the left and right sides across the central body part, and one joint part is connected to the back of the packer part. The packer part and the lock bolt body are connected to each other by being removably inserted into the end of the lock bolt body, and the other joint part is removably inserted into the tip of the lock bolt body.

That is, since this lock bolt has a bit portion formed at its tip, it can be rotated by attaching a rotating shaft of a rock drill or the like to the rear end of the lock bolt. Due to this rotation, the rock bolt itself acts as a drill of a rock drill or the like to drill a hole, and after the hole is drilled, it can remain as a rock bolt in the drilled hole. Therefore, the conventional method of removing the drill after drilling the hole,
No need to insert lock bolts. In addition, as the lock bolt itself acts as a drill as described above and drills a hole large enough to accommodate itself, it is no longer necessary to drill a hole that is much larger than the lock bolt, as was the case in the past. This eliminates the need for inserting lock bolts and simplifies the construction work. In addition, this lock bolt has a stationary mixer installed at the rear end of the packer section, which corresponds to the approximate center of the lock bolt, rather than at the tip of the lock bolt as in the conventional example, so the flow path from the stationary mixer to the discharge hole becomes longer. . As a result, the urethane resin mixture, which once entered a turbulent flow state due to mixing by the static mixer, becomes a nearly laminar flow state as it flows through the above flow path, and is uniformly discharged from the multiple discharge holes on the outer periphery of the tip of the packer part. It erupts in such a state. Therefore, local variations do not occur in the consolidated region formed around the lock bolt, and the consolidated strength becomes uniform. Furthermore, since the static mixer is attached to a mounting section within the packer section, a conventional fixing socket is not required, and the number of parts can be reduced.

Next, this invention will be explained in detail based on examples.

〔Example〕

1 to 3 show an embodiment of this invention. In these figures, 1 is a lock bolt, which includes a packer part 2 consisting of a hollow pipe with a closed end, a stationary mixer 3 fixed in the packer part 2, and a lock bolt made of a hollow pipe on the inner wall near the left and right openings. It consists of a lock bolt body 4 on which threaded portions 4a and 4b are formed, and a pipe joint 5 that connects the packer portion 2 and the lock bolt body 4. This lock bolt 1 has an outer diameter of 27
mm, the inner diameter is 14 mm, the total length A is approximately 3 m, the length B of the packer portion is 1 m, and the length C of the lock bolt body 4 is set to 2 m.

The packer part 2 is constructed by removably fitting a bit 7 having a blade part into the outer circumference of the tip of a packer part main body 6 made of a hollow pipe. The outer periphery of the tip of the packer body 6 is formed into a tapered portion whose diameter becomes smaller toward the tip, and a bit 7 whose inner circumferential surface is formed into a tapered portion corresponding to the tapered portion is detachably attached thereto. is mated to. In this case, the rotational force of the rotating shaft of the rock drill or the like is transmitted to the bit 7 through the taper section, but the connection between the bit 7 and the main body of the packer 6 is due to the taper section as described above. Because it is made and strong,
No transmission loss of rotational force to bit 7 occurs. The bit 7 is made of a hollow pipe with a closed tip, and four blades 8 are provided at 90° intervals in the circumferential direction on the end face of the tip. A center hole 9 is formed in the center of the end face, and outer peripheral holes 10 are formed between the blades 8, respectively, and these holes 9 and 10 are formed in the hollow part in the packer part 2. 2a and the outside are in communication. A hollow portion 2a is formed on the inner wall of the rear end of the packer main body 6 at a predetermined length from the rear end.
Threaded portion 11 formed to have an inner diameter larger than the inner diameter of
is provided, and the inner part of this threaded part 11 and the hollow part 2
The boundary with a is a stepped portion 12.

The stationary mixer 3 has its own ring-shaped mounting plate 13 positioned on the stepped portion 12, and is disposed with its tip facing toward the tip of the packer portion 2.
To explain in more detail, as shown in FIGS. 4 to 6, the stationary mixer 3 is integrally formed entirely of plastic, and includes a linear central shaft 14, a plurality of single blades 15, and a plurality of double blades. It is composed of a blade 16 and a ring-shaped mounting plate 13.

The plurality of single blades 15 have a semicircular plate shape (sixth
(see figure), and are arranged at predetermined intervals along the axial direction of the central shaft body 14 in an inclined state so as to form an upward slope rising from one end 15a to the other end 15b, as shown in FIG. It is set up. Then, the semicircular right side 17a of the semicircular plate-shaped body (Fig. 5,
(see FIG. 6) is connected and integrally attached to the central shaft body 14 at its center. The above plurality of double blades 1
As shown in FIG. 7, the blades 6 are provided at positions corresponding to the single blades 15 across the central shaft body 14, with a predetermined interval maintained and inclined in the opposite direction to the single blades 15. The double blade 16 is composed of a blade 18 having the same shape as the single blade 15, and a blade 19 having approximately the same shape as the blade 18 but slightly shorter in length. end 18
b, 19b are connected. The blade is disposed with its separated side positioned between the single blades 15 and 15. In this case, the double blade 16 connects the blade ends 18a, 19a on the separated side to the blade ends 19a, 18a on the separate side of the adjacent double blade 16, and connects the blade ends 18a, 19a on the connection side
Connecting portion 20 at 8b, 19b with single blade 15
is connected to the end portion 15a of the blade, and has a semicircular straight side 17b similar to the single blade 15 (see FIGS. 5 and 6).
It is attached and fixed by being connected and integrated with the central shaft body 14. The double blade 16 and the single blade 15 are provided with the central shaft body 14 in between and are connected to the central shaft body 14, respectively, and as described above, the double blade 16 and the single blade 15 are connected to each other by the connecting portion 20 of the double blade 16. They are interconnected, and further, the portions facing each other with the central shaft body 14 in between are interconnected, thereby forming the entire stationary mixer 3 into a strong structure.

The ring-shaped mounting plate 13 has a ring shape with a hole 21 formed in the center, and mounting portions 22 of the single blade 15 and the double blade 16 on the side of the mounting plate 13 are provided at opposing portions of the ring shape. , 23 are connected. In this case, the central shaft body 14 is set to be orthogonal to the ring-shaped mounting plate 13. Also,
The root portion of the central shaft body 14 is cut in the middle and is separated from the ring-shaped mounting plate 13.

The static mixer 3 configured in this manner has the ring-shaped mounting plate 13 located at the step 12 on the back side of the threaded portion 11 in the packer portion 2, as described above.
It is inserted with its own distal end facing toward the distal end of the packer portion 2.

Reference numeral 5 denotes a pipe joint, in which cylindrical joint parts 24a and 24b whose outer peripheral surfaces are threaded extend from the left and right openings across the hollow pipe-shaped central part 5a,
One cylindrical joint part 24a is fitted to the threaded part 11 at the rear end of the packer part 2, and the other cylindrical joint part 24b is fitted to the threaded part 4a at the tip of the lock bolt main body 4. and the lock bolt main body 4 are joined. In this case, the cylindrical joint part 24 of the pipe joint 5
The outer periphery of the tip of a presses against the ring-shaped mounting plate 13 of the static mixer 3, thereby fixing the static mixer 3.

25 is a threaded portion 4b at the rear end of this lock bolt 1.
This is a joint with a matched check valve. This lock bolt 1 is disassembled during transportation and storage.

8 to 10 show modifications of the lock bolt shown in FIG. 1. That is, this lock bolt 1' has a bit 26 integrally formed at the tip of the packer portion 2'. In this case, the blade portion 27 of the bit 26 is formed to be bifurcated from the root, and the tips of the bifurcated portions are each formed into a blade 27a. And the branched blade part 2
An outer circumferential hole 28 is formed in the root portion of 7.
Since the other parts are substantially the same as the lock bolt shown in FIG. 1, the same parts are given the same reference numerals.

The above-mentioned rock bolt is installed as a drill in the rock drilling equipment of a rock drilling machine, and drills a hole in the ceiling part at the tip of the tunnel face in an upward direction (angle θ = 10 to 20 degrees), and at the same time drills the hole itself. Enter into the drilled hole, disconnect from the rock drilling rig while entering the drilled hole to the root side, and connect the hose 33 with the connecting unit 32 to the joint 25 with a check valve at the rear end with one touch. The rock solidification is performed by receiving liquids A and B of two-component foamed urethane resin from a urethane resin press-in pump through a hose 33.

To explain this in more detail, first, as shown in FIG.
Water and air are press-fitted into the lock bolt 1 from the water and air supply pipe 30 provided in the lock bolt 1, and are discharged from the center hole 9 and the outer peripheral hole 10 at the tip of the lock bolt 1,
The soil, sand, etc. scraped by the blade 8 of the lock bolt 1 is moved backward inside the hole 31 along the outer periphery of the lock bolt 1 and discharged from the opening of the hole 31 to the outside.
1. Perform drilling. In this way, the hole 31 is formed using the lock bolt 1 as a drill, and the hole 31
Leave the lock bolt 1 inside, then connect the joint 25 with check valve to the rear end of the lock bolt 1, connect the hose 33 with the connection unit 32 with one touch as shown in Fig. Inject liquid and B liquid.

This urethane resin hardens within 5 to 30 seconds after mixing liquids A and B, and, for example, liquids A and B are used at a blending ratio of 1:1. The above liquid A has a hydroxyl value of 250 to 450 KOH prepared by using a combination of several types of primary polyols with a hydroxyl value of 20 to 6,400 KOH mg/g and an average molecular weight of 18 to 5,000 and having more than two functional groups.
mg/ of the polyol liquid, as liquid B, diphenylmethane having two or more isocyanate groups.
Average molecular weight 174-2000, isocyanate group content 18-2000, mainly composed of at least one of 4,4'-diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (polymeric MDI, crude MDI), and tolylene diisocyanate (TDI). Consists of 48% by weight isocyanate liquid. The two liquids A and B thus injected under pressure reach the pipe joint 5 in a laminar flow state, and from there they are mixed and pumped by a static mixer 3 (see FIG. 1). That is, the two liquids A and B that have reached the static mixer 3 in a laminar flow state enter the left and right halves of the static mixer as shown in Figures 4 and 6, and turn left (counterclockwise) with respect to the traveling direction X. It is mixed and transferred by passing through single and double blades every half rotation while rotating in different directions. In this case, the right half of the static mixer 3 is provided with a V-shaped double blade 16, and the left half is provided with a single blade 15, and when the urethane resin rotates from the left half to the right half, the inlet side becomes wide and the outlet side becomes narrow. The flow velocity is increased by the action of the V-shaped double vanes 16, and returns to the initial velocity when returning from the right half to the left half. In other words, liquid A and liquid B are on the right half,
Mixing occurs while rotating in the same direction due to the difference in flow velocity on the left half. To explain this state in more detail with reference to FIG. 7, when liquid A, indicated by the black arrow, is introduced into the static mixer 3 through the hole 21 of the ring-shaped mounting plate 13, liquid A will flow as shown in the figure. Along the blade surface of the single blade 15 tilted upward, one end 15a
It flows diagonally upward toward the other end 15b, and when it reaches the vicinity of the other end 15b, due to the action of the inner wall of the packer portion 2, the flow flows from the separated side of the double blade 16 located on the opposite side with the central shaft body 14 in between ( It flows into the open side while turning left. From this state, liquid A flows from the separated side of the double blades 16 to the connecting part 20 side, and in this process, the speed is increased (the flow rate becomes faster because the flow path gradually narrows), and part of it branches as shown in the figure. arrow A ₁ ,
As shown by A ₂ and A ₃ , it turns to the left and flows between the single blades 15 located on opposite sides of the central shaft body 14, and in the same way, the remaining part turns to the left as shown by arrow A' and flows closer to the direction of travel X. It turns left and flows between the single blades 15. The flows indicated by these arrows A', A ₁ to _{A 3} are accelerated and are faster than the initially introduced flow velocity. On the other hand, the B liquid shown by the white arrow descends along the outside of the blade 18 of the double blade 16 as shown by the arrow, and when it reaches the bottom part of it branches due to the action of the inner wall of the packer part 2. arrow B ₁
As shown, the flow turns left between the single blades 15 located on the opposite side with the central shaft body 14 in between, and similarly, the remaining part turns left as shown by arrow B' and flows into the single blades 15 on the side of the traveling direction X. flows between. The flows indicated by these arrows B' and _B1 are not accelerated because the intervals between the single blades 15 are the same in all parts, and flow at approximately the same speed as the initial introduction speed. In this case, black arrow A ₁ and white arrow B ₁ flow in the same channel, black arrow A ₂ and white arrow B' flow in the same channel, and the speeds of A ₁ and A ₂ are B ₁ , Since it is faster than B′,
An overtaking phenomenon occurs between A ₁ and A ₂ , and the two liquids are mixed due to the difference in flow velocity. In this way, both liquids A and B are mixed due to the difference in flow rate, and are mixed and transferred in the traveling direction X without substantially reducing the transfer speed. From this mixed turbulent state, liquids A and B turn into a uniform laminar flow state by the time they reach the central hole 9 and the outer circumferential hole 10 at the tip of the lock bolt 1, and in that state, they flow through the central hole. 9 and the outer peripheral hole 10 to a predetermined position within the hole 31 (see FIG. 12). In this case, the fast-curing urethane resin liquid that is first discharged flows from the tip of the hole 31 toward the opening, hardens in the process, and becomes completely hardened by the time it reaches the opening of the hole 31 and closes the opening. This prevents leakage of the resin liquid that will be discharged later.
After that, the discharged urethane resin liquid flows into the hole 3.
1, and then the urethane resin liquid penetrates into the ground due to the discharge pressure and hardens together with the pore-filling urethane resin liquid. Due to this curing, the press-fitting pressure of the urethane resin liquid increases, so the press-fitting is stopped at that point, and the connection unit 32 is removed with one touch. In this way, the lock bolt 1 is fixed in the hole 31.
The surrounding ground is consolidated with hardened resin. This state is shown in FIG. In this way, the rock bolts 1 are inserted into the holes 31 drilled at predetermined intervals in the ceiling section at the tip of the tunnel face, and rock consolidation is performed.

As described above, since the lock bolt 1 is provided with a bit at the tip, it can be rotated by attaching a rotating shaft of a rock drill or the like to the threaded portion 4b at the rear end. By this rotation, a hole can be drilled, and after the hole is drilled, it can remain as it is. This eliminates the need for drilling a hole with a rock drill, etc., pulling the drill out of the hole, and then inserting a hollow pipe, such as a pack car, as in the conventional method, which significantly shortens the construction work. It becomes wet.

In addition, since the static mixer 3 is attached to the rear end of the packer part 2, which corresponds to the approximate center of the lock bolt 1, the flow path between the static mixer 3 and the discharge hole at the tip of the lock bolt 1 becomes long, and the The urethane resin liquid that has become turbulent in the mixer 3 becomes a uniform laminar flow while passing through this flow path, and is uniformly discharged from the plurality of discharge holes. As a result, no local variation occurs in the consolidated region, and a state of uniform consolidation strength can be obtained. Moreover,
Since the static mixer 3 is fixed with its attachment part 13 sandwiched between the step part 12 at the rear end of the packer part 2 and the tip of the pipe joint 5, no special member is required for fixing the static mixer 3. Furthermore, the static mixer 3 can effectively mix both liquids A and B of the two-component foamed urethane resin without reducing the transfer speed, making it possible to use fast-curing urethane resin, making it possible to use a fast-curing urethane resin. It is also possible to eliminate the need for complicated operations such as blocking the hole entrance using a gasket to prevent urethane resin from leaking.

[Effect of idea]

As mentioned above, the rock bolt of this invention has a bit part at the tip, so when attached to a rock drill, etc., it can perform the role of a rock drill.
After the hole is drilled, it can remain in the hole as a lock bolt. Therefore, the hole drilling work etc. can be simplified.
Further, since the stationary mixer is positioned approximately at the center of the rock bolt and the mixed chemical liquid is made into a laminar flow state and discharged from the discharge hole, the rock mass can be solidified in a uniform state. Furthermore, there is no need to put the static mixer inside through the opening at the end of the lock bolt and secure it with a socket as in the past, making it easier to install the static mixer, and at the same time eliminating the need for a socket, the number of parts can be reduced. Become.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of this invention, Fig. 2 is a perspective view of the main part thereof, Fig. 3 is an explanatory view thereof, Fig. 4 is a perspective view of a static mixer, and Fig. 5 is Fig. 4. Fig. 6 is a state diagram of Fig. 4 seen from the direction of arrow A, Fig. 7 is an explanatory diagram of the operation of Fig. 4, and Fig. 8 is a cutaway cross section of another embodiment. Figure, No. 9
The figure is a state diagram of FIG. 8 viewed from the arrow direction, FIG. 10 is an explanatory diagram thereof, FIGS. 11 to 13 are explanatory diagrams of how to use this invention, and FIG. 14 is an explanatory diagram of a conventional example. . 1... Rock bolt, 2... Police car club, 2a
...Hollow part, 3...Static mixer, 4...Lock bolt body, 4a, 4b, 11...Threaded part, 5...
...Pipe joint, 5a...Central part, 7...Bit, 9...
...Central hole, 10...Outer hole, 15...Single blade,
16...Double blade, 24a, 24b...Cylindrical joint part.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A packer portion consisting of a hollow pipe with a closed end, a static mixer with mixing blades installed within the packer portion, a lock bolt body made of a hollow pipe, and the rear end of the packer portion. and a pipe joint that connects the lock bolt body with the tip of the lock bolt body, the packer portion has a bit portion at the tip, and a discharge hole is bored in the bit portion,
A stationary mixer attachment part is provided on the inner wall at the rear end of the hollow part, the stationary mixer is attached to the stationary mixer attachment part, and the pipe joint has coupling parts on the left and right sides of the central body, and one A joint part is detachably inserted into the rear end of the lock bolt body, and the other joint part is detachably inserted into the tip of the lock bolt body to join the lock bolt body to the lock bolt body. Lock Bolt. (2) A static mixer consists of a ring-shaped mounting plate, a central shaft extending perpendicularly from the center of the ring of the ring-shaped mounting plate, and a central shaft sandwiching the central shaft so as to form a circle around the central shaft. A central shaft body is provided with a semicircular single blade and a semicircular double blade, and the semicircular single blade is inclined upwardly from one end of the semicircular shape toward the other end. A plurality of semicircular double blades are provided at appropriate intervals along the axial direction of the blade, and the semicircular double blade joins one semicircular end of the two blades and separates the other end, and the separated side is connected to the single blade. A lock bolt according to claim 1 of the utility model registration claim, wherein a plurality of lock bolts are provided at appropriate intervals along the axial direction of the central shaft body and are inclined in the opposite direction to the single blade while being positioned between the lock bolts. . (3) The joining parts on the left and right sides of the pipe joint are each formed into a threaded part, and the rear end of the connector part has a threaded part that can be joined to one of the threaded parts, and the tip of the lock bolt body has a threaded part that can be joined with the other threaded part. The lock bolt according to claim 1 or 2, wherein a threaded portion that can be connected to the threaded portion of the lock bolt is formed, respectively. (4) The static mixer positions its own ring-shaped mounting plate on the step at the boundary between the threaded part of the inner wall at the rear end of the packer part and the hollow part at the back thereof, and attaches it to the threaded part. The lock bolt according to claim 2 or 3, which is mounted and fixed by being sandwiched between the tip of one threaded portion of a pipe joint and the stepped portion.