JPH03241115A - Seal packer method for injection bolt - Google Patents

Abstract

PURPOSE:To prevent the outflow of chemicals by inserting a bolt into a hole after the ends of a tube are fixed to the peripheral surface of a hollow injection bolt, and injecting foamable solidifying resin into the tube to seal spaces closely. CONSTITUTION:An opening is provided to the rear end of a hollow injection bolt 1, and a one-touch joint 6 provided with a check valve is connected to the opening. After that, the ends of a tube 5 of cloth is fixed to the peripheral surface of the injection bolt 1. At that time, the end of a sealing foamable solidified chemical grouting pipe is bound together with the cloth of fix so that it is capable of injecting into the tube 5. A hole is bored into a bedrock 3 to insert the injection bolt 1 into a hole 4, and the tube 5 is filled with the foamable solidifying resin. According to the constitution, the foamable solidifying resin makes foamable solidified reaction in the tube 5, spaces between the injection bolt 1 and bedrock 3 are sealed while pushing the tube 5 in every direction, and water gushing from the inside of the excavated hole 4 or leakage of water can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a seal packer construction method for injection bolts. For more details, refer to the New Au5trian TunneltngM method in civil engineering or construction work.
When injecting various chemical solutions for the purpose of solidifying, stabilizing, strengthening, and waterproofing of bedrock, ground, and artificial structures, as well as filling cracks and voids, it is necessary to connect the injection bolt to the ground or substrate. This is a construction method for sealing gaps, in which a tube made of fabric is provided on the injection bolt in advance, and after the injection bolt is inserted into a hole previously drilled in the ground or substrate, foam hardening is performed in the tube. The present invention relates to a seal backer construction method for injection bolts, which is characterized by injecting a synthetic resin and completely sealing the gap between the bolt and the ground or base.

[Prior art] Conventionally, methods for sealing the gap between the injection bolt and the rock mass in the Natume method include (1) sealing the mouth of the injection bolt and the ground with quick-setting cement;
2: A method of pushing J cloth, a rag, a piece of wood, etc. into the gap, (3) a method of impregnating the cloth with hard foamed urethane resin and then pushing the cloth into the gap, (4) a method of pushing the cloth into the gap; As described in 8B-83687, a liquid-absorbing base material such as a waste cloth is wrapped around the injection bolt, and this base material is impregnated with a foaming resin, and then the bolt is inserted into the hole. There are methods of sealing by foaming, and (5)
) As described in Japanese Patent Publication No. 83-63888, a first gasket and a second gasket are provided on the outer periphery of the injection bolt, and various sealants are injected between the two gaskets to seal the soil. There are methods to seal gaps between bolts.

[Problem to be solved by the invention] However, among the conventional seal injections mentioned above, (1)
) With the method of using quick-setting cement, it is difficult to insert the quick-setting cement deep into the gap between the injection bolt and the ground, and it is only possible to seal around the mouth.
Furthermore, since quick-setting cement is hard and brittle, it cannot withstand the slight shock and vibration that occurs when grout is injected from the injection bolt, as well as the back pressure of high-pressure grout, resulting in cracks, bolts, and bonding surfaces with the ground. Peeling is likely to occur. As a result, grout leakage occurs, making it impossible to perform grout injection work reliably. In addition, (2) a method of sealing and fixing by pushing a cloth or piece of wood into the gap between the injection bolt and the ground is also recommended when injecting the main grout (especially when the injection pressure is 3 kg/cd).
There is a problem that the chemical solution cannot withstand the pressure (during high-pressure injection (0 or more)), and the rag or the like is pushed back, causing the chemical solution to leak.

In addition, (3) the method of pre-impregnating a rag with foamed hard urethane resin or the like and then pushing the rag into the gap between the injection bolt and the other threads to fix the seal has the same sealing effect as described in (1) to (a) above. Although it is slightly improved compared to the conventional method,
It is still not possible to sufficiently seal and fix the injection bolt.

Furthermore, (4) the method described in Japanese Patent Publication No. 63-8H87 may also result in the foamable resin not being sufficiently foamed or being foamed and hardened in an uneven state, resulting in the compressive strength and adhesive strength of the resin being reduced. If the grout is weak or extremely brittle, the injection bolt may not be sufficiently sealed and fixed, and there is a possibility that the chemical solution may leak from the seal during main grout injection.

Furthermore, (5) with regard to the method described in the Japanese Patent Publication No. EA-EAESS, even if the injection material is put into the gap between the first and second packing of the injection bolt and the gap between the ground and the ground, both packings are sealed. It is difficult to reliably fill the sealing liquid and cure it during this period. For this reason, liquid leakage is likely to occur from the packing part, leaving an unsealed space in the sealing part.
There is a problem in that the chemical solution tends to leak when this grout is injected. In particular, when there is spring water or water leakage, there is a problem with the conventional method that the sealing agent is washed away by the spring water before it hardens, making it impossible to fix the seal at all.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a sealbacker construction method that eliminates the drawbacks of the prior art. That is, an object of the present invention is to provide a seal backer construction method that can reliably seal the gap between the injection bolt and the ground and prevent the chemical solution from flowing out due to spring water or water leakage.

[Means for Solving the Problems] The injection bolt seal backer construction method of the present invention fixes both ends of a tube made of fabric to the outer peripheral surface of a hollow injection bolt, and pre-drills the injection bolt in the ground or base. The injection bolt is inserted into a predetermined hole, and then a foamed curable resin is injected into the tube to tightly seal the gap between the injection bolt and the earth or base.

[Example] Hereinafter, the injection bolt seal backer construction method (hereinafter referred to as "seal construction method") of the present invention will be explained based on the drawings.

FIG. 1 is a schematic explanatory diagram of an example of a device used in the seal construction method of the present invention.

In Fig. 1, (1) is a hollow injection bolt, which bolt (1) has an opening at its rear end, in which a check valve (one-touch joint with a sword) is installed. (
6) is connected. Then, a chemical solution for solidifying and stabilizing rock etc. is injected into the injection bolt (1) through this joint (6). The injection bolt (1) is attached to the ground (
3) A hole (
4) (see Figure 3). In addition, the sealing method of the present invention can be widely applied to the ground targeted for civil engineering work in addition to the ground (3) such as bedrock, and even to sealing cracks and voids in artificial structures such as concrete. In the specification, the term "rock or base" is a broad concept that includes all of them.

(5) is a tube made of cloth whose both ends are fixed to the outer peripheral surface of the injection bolt (1). Fixing to the bolt (1) may be done with a string or band, or may be done by adhesive, and is not particularly limited in the present invention.

The front part □□□ of the bolt (1) is formed with a thick wall, and the rear part 01) is formed with a thin wall, and there is a step inside the bolt (1) at the boundary between the front part (roll) and the rear part 01). A static mixer (8) is provided for mixing the medicinal solution injected into the container. The chemical solution mixed by the static mixer (8) is injected into the borehole (4) through the hole 02) formed in the front part (10) of the bolt.

The tube (5) is made of natural fibers, chemical fibers, synthetic fibers, or inorganic fibers alone or in combination, or knitted fabrics, woven fabrics, nonwoven fabrics, felts, or thin materials made of resin-processed fibers, or a combination of these. It is made of one or two or more layers of fabric that has been treated with resin.

Specifically, as natural fibers, those obtained from cotton, flax, hemp, Manila hemp, coconut, wool, cashmere, silkworm, asbestos, bulb, mimmata, paper mulberry, etc. can be used, and as chemical fibers, rayon , cupro, acetate, and other recycled or semi-synthetic fibers, nylon, vinylon,
Synthetic fibers such as acrylic, polyester, polyethylene, polypropylene, polyurethane, polyvinyl chloride, and vinylidene can be used. As the inorganic fiber, those made of metal, glass, rock, carbon, etc. can be used.

The performance required of the fabric constituting the tube (5) in the present invention is that it is breathable, watertight, and has the strength to withstand water pressure of usually about 3 to 4 kg/cj G. preferable. Specifically, the fabric is φ10
c+e% A cylindrical bag with an eave of about 20 cm in length is made, and about 200 g of a liquid drug with a viscosity of about 30 to 50 cP/20"C is quickly injected into it, and 100 g of the same drug is released from the bag.
The time required for penetration is 5 to 600 seconds, preferably 1
The time is preferably 0 to 300 seconds. If the fabric tube has breathability and moisture properties within this range, when a sealing foaming chemical solution is injected into the tube, the sealing solution will excessively flow out of the tube and the sealing effect will be affected. In addition, it is possible to prevent normal pressure or high pressure water from seeping into the tube due to spring water or water leakage from the ground or bedrock, and reducing the sealing effect. On the other hand, if the fabric has excessive airtightness or watertightness and the foamed curable resin does not permeate to the outside at all, the adhesion and adhesion with the ground or base material may decrease, and the foaming pressure may cause the tube to This is undesirable because it may cause damage.

For example, if a rubber tube or the like is used, an air pocket may form inside the tube, which may cause the tube to rupture, or the unevenness of the drilled hole may not be sufficiently sealed, making it impossible to obtain a complete sealing effect.

The foaming curable resin for sealing that is injected into the fabric tube (S) may be any resin as long as it is liquid at room temperature and foams and hardens in a short period of time. It is preferable to use a foamed urethane resin from the viewpoints of foam sealing effect, economical efficiency, and the like.

In general, foamed urethane resins are made of two types: an A component whose main component is a polyol component and a B component whose main component is a polyisocyanate.
In terms of foam properties, soft, semi-hard, and hard foams can be used; however, from the viewpoint of strength, adhesion, and sealing effect, it is preferable to use semi-hard or hard foam urethane resin. preferable. Usually, these foamed urethane resins contain polyol, foam stabilizer, foaming agent,
A consisting of catalyst, viscosity reducer, flame retardant, inorganic filler, etc.
Using component B consisting of a component and an organic polyisocyanate,
These A component and B component are N CO/OH ff1O,8
It can be obtained by mixing with a static mixer or the like at a reaction ratio of /l to 3/l.

Usually, the curing time is 0.5 to 5 minutes, and the foaming ratio is 2 to 5 minutes.
30 times, especially 2 to 10 times, and the compressive strength is about 4
It is preferable that the foam exhibits a performance of 10 to 100 kg/c- in double foaming.

Such foamed urethane resin can be manufactured by a known method. That is, polyols include ethylene glycol, diethylene glycol, triethylene glycol,
Polyhydric alcohols such as propylene glycol, dipropylene glycol, tripropylene glycol, glycerin, sorbitol, sugar, aniline, ethylenediamine, mono-, jetanolamine, triethanolamine, etc. alone or in combination, or in addition, propylene oxide, Mainly polyether polyols having a molecular weight of 100 to 10,000 are obtained by addition polymerizing alkylene oxides such as ethylene oxide. As the foam stabilizer, surfactants such as ethylene oxide addition polymers of various nonylphenols, oxyalkylene-modified siloxanes, organopolysiloxanes, etc. are used. As the blowing agent, for example, trichloromonofluoromethane, methylene chloride, hexane, water, etc. are used. In addition, triethylamine, triethylenediamine, tin octylate, dibutyltin laurate, morpholine, etc. can be used as a catalyst, and phosphorus, halogen compounds, antimony trioxide, aluminum hydroxide, boric acid, etc. can be used as a flame retardant. Can be used. Further, as the inorganic filler, cement, calcium carbonate, bentonite, clay, sand, etc. can be used.

On the other hand, as the organic polyisocyanate of component B, aromatic polyisocyanates such as tolylene diisocyanate, polymethylene polyphenyl isocyanate, and diphenylmethane diisocyanate; alicyclic polyisocyanates such as xylylene diisocyanate, tetramethylene xylylene diisocyanate, and isophorone diisocyanate; Aliphatic diisocyanates such as hexamethylene diisocyanate may be used alone or in mixtures, or modified products of these with water or low molecular weight alcohols may be used alone or in mixtures. Among these, polymethylene polyphenylisocyanate, Schiffermethane diisocyanate, or low-molecular-weight alcohol modified products thereof are preferred. Furthermore, if necessary, an inert low-boiling diluent such as methylene chloride, acetone, or trichloromonofluoromethane may be added to these in order to improve injection workability and foamability.

To inject a chemical into a tube, first, a steel injection bolt with a fabric tube and a sealing pipe set in advance is inserted into a predetermined hole in the ground. Next, the A and B components of the sealing chemical solution mentioned above were quickly mixed in a predetermined mixing ratio for 10 to 20 seconds using a drill mixer, etc.
Transfer it to a 000ml cartridge or grease pump, joint it to a sealing pipe, quickly inject it into the tube, immediately seal the vibrator, and foam and harden in the tube in a short time.

Alternatively, the A component and the B component may be discharged at a predetermined ratio using a proportional mixing pump or the like, passed through a static mixer or the like, mixed uniformly, and then injected into the tube.

Although FIG. 1 shows a case where an integrally molded bolt is used, it is also possible to use a bolt whose front part and rear part are connected by a joint, as shown in FIG.

Next, the procedure of the sealing method of the present invention will be explained.

First, the fabric as described above is processed into a cylindrical shape with a diameter of about 4 to 1 can and a length of about 30 to 1 m, and one end of the cylindrical shape is fixed to the front part of the injection bolt by tying it with thread or a rubber band. At this time, the tip of the foam curing liquid injection vibrator for sealing is tied and fixed together with the fabric so that it can be injected into the fabric tube. Next, the other end of the cylindrical fabric is fixed by tightening it to the injection bolt with thread, a rubber band, or the like. In order to improve the sealing effect, it is preferable that the length of the cylindrical fabric along the injection bolt is 30 crn to 1 m, but this is not particularly limited.

Further, the diameter of the fabric tube may be appropriately selected depending on the purpose and the diameter of the hole to be drilled, but it is generally preferable that the length be approximately the same as the diameter of the hole to be drilled.

After preparing the injection bolt in this manner, the injection bolt is inserted into a hole previously drilled in unstable rock or other ground using a leg auger or the like. The diameter and depth of the hole will vary depending on the type of rock and the purpose of sealing, but for example, in the case of stabilizing rock with a fracture zone, the diameter of the hole is approximately 5cI1.
It is around 1 and 2 to 3 meters deep.

Next, joint the tip of the sealing liquid injection nozzle into the sealing liquid injection pipe and quickly mix a foamed curable resin such as the two-component foamed urethane resin as described above to inject approximately 4
Inject 00ml to 1g to fill the tube. The foam hardening chemical solution injected in this way immediately causes a foam hardening reaction within the tube, and while pushing the fabric tube provided around the outer periphery of the injection bolt in all directions, the gap between the injection bolt and the ground is reduced by 1 minute. Adheres completely without any gaps and provides a strong seal. In addition, since the fabric tube is watertight, even if there is water leakage or spring water from inside the drilled hole, the tube can be reliably sealed without being affected by this.

After the gap between the injection bolt and the ground is completely sealed in this way, so-called cement milk, water glass, various organic grouts, etc. are injected through the injection bolt at an appropriate pressure. FIG. 3 shows a state in which the sealing foaming chemical injected into the fabric tube solidifies, and then the rock improver such as cement milk is injected into the bolt. In this case, the chemical solution will not leak between the bolt and the ground, and complete injection work can be carried out, strengthening the stability of the rock and ground, stopping water, and filling cracks and voids in the concrete. It is possible to achieve the intended purpose.

Next, the seal construction method of the present invention will be explained based on Examples, but the present invention is not limited to these Examples.

Examples 1 to 8 and Comparative Examples 1 to 2 The ground at the tunnel excavation face has a fractured zone made of granite, rhyolite, and talus, and is a defective tunnel where some spring water also occurs. The excavation work was judged to be dangerous and difficult due to the presence of spring water. To promote construction 2
Liquid foamed rigid urethane was injected using the sealing method of the present invention to stabilize the fracture zone and stop water.

For comparison, injection was also performed using the conventional quick setting cement seal method or the rag push seal method.

First, the top part of the face of the defective rock mass should be
Twelve holes were drilled in an arch shape at a pitch of 2m at an angle of 5° ((
Steps a) to (1)) were performed. The depth of the hole was approximately 3 m, and the hole was drilled using a 421 mφ bit leg auger. Of the 12 holes, 8 (ω ~ peaks) were made using the sealing method of the present invention, and of the remaining 4 holes, the holes were made of polypropylene nonwoven fabric tubes with almost no watertightness, and +j> were made of non-ventilated holes with no air permeability. A general chloroprene rubber tube was used.

In addition, the remaining two were sealed using the conventional quick setting cement seal method ((
k) ) or a rag push-in seal method ((11)), a two-speed hard foamed rigid urethane resin was injected.

Next, we made carbon steel (material JIS G3) as shown in Figure 1.
4455TK) 117C) hollow steel bolt (length 3
ms outer diameter 27.2mm, inner diameter 14.4a+m, the tip is sealed, 8 holes of φ8I1m are drilled approximately 1m from the tip, and a static mixer is installed inside). 50ca+~ from 1m to the tip
A cylindrical tube made of various fabric materials shown in Table 1 with a diameter of approximately 5 cm and a length of 1 m is placed approximately in the center of the 1 m long bolt, and the tip of the injection pipe for sealing is tied together with a string, and the tube is set on the steel bolt. , and the tip of the injection hose for sealing was jointed and inserted into the injection hole of ω~(1>, which was previously drilled) to complete preparation for sealing.

Next, in the fabric tube, 10% of a mixed polyol of polyether polyol with a molecular weight of 300 and dipropylene glycol prepared by addition polymerization of ethylene oxide to glycerin was placed.
0 parts (average hydroxyl value 643 KOHig/g), water 0.
5 parts, foam stabilizer (DKS Silicone D33 manufactured by Daiichi Kogyo Seiyaku ■)
2) Part 2, catalyst (Kao ■Olyzer No. 31
(Product name). 1 part by weight of triethylene diamine dissolved in dipropylene glycol at a concentration of 33 wt%,
Component A, which is a mixture of 10 parts by weight of methylene chloride, and component B, which is a mixture of 20 parts by weight of methylene chloride and 180 parts by weight of Millionate MR-100 (Japan Polyurethane side type polymethylene polyphenylisocyanate), are passed through a static mixer to produce a high-performance proportional blending method. Approximately 1 p was injected using an infusion pump. This sealing chemical has an initial mixed viscosity of approximately 35 cP/20°C, a gel time of approximately 40 seconds/20°C, a rise time of approximately 50 seconds, and a
It becomes a rigid foam with 5 times expansion. In addition, the strength of the solidified body, which is restrained in a steel pressure mold and foamed and hardened approximately four times, is as follows.
It exhibited a bending strength of approximately 40 kg/cd and a compressive strength of approximately 55 kg/cj. The foam hardening is completed in about 5 minutes after injection into the injection holes set in () to (1), and the gap between the injection bolt and the ground is completely sealed, and the spring water from the ground is drained from the injection bolt. It now flows out to the front through the inside.

After completely sealing and fixing the injection bolt in the borehole of the ground, the A and B components of the two-wave hardening foamed rigid urethane resin similar to the sealing chemical were added to the above-mentioned static mixer and check valve interior. It was injected through a pressure hose jointed to a perforated carbon steel injection bolt. The compounding ratio is the same as that of the sealing resin mentioned above, and approximately 150 kg of chemical liquid is injected per hole using a proportional compounding high-performance injection pump at an injection pressure of 10 kg.
Injected at ~30 kg/cjG. In addition, at the end of injection, the injection pressure was increased to 40 kg/cjG, and the presence or absence of liquid leakage toward the front side of the injection port was checked to determine the sealing effect.

Also, for comparison, hole drilling (1) for the fabric tube
For the hole, a polypropylene nonwoven tube with almost no watertightness was used, and for the hole +j+, a chloropylene rubber tube with no air permeability was used. For rough drilling + k), instead of installing a fabric tube, the mouth of the injection bolt was tightly sealed with quick setting cement (Comparative Example 3), and for hole drilling (1), a cloth was pushed in to seal it (Comparative Example) 4) Later, in the same manner as in Example 2
Injected with a fast-curing foaming rigid urethane resin.

The above results are shown in Table 1.

[As is clear from Table 1 below, the sealing method of the present invention can reliably seal the gap between the injection bolt and the ground, and when injecting grout into the injection bolt, the chemical solution It can be seen that there is no leakage to the front side of the bolt.

[Effects of the Invention] As explained above, according to the sealing method of the present invention, the gap between the injection bolt and the ground can be reliably sealed.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of an example of a device used in the sealing method of the present invention, FIG. 2 is a schematic explanatory diagram of another example, and FIG.
The figure is a schematic explanatory view showing the sealing method of the present invention. (Main symbols in the drawing) (1): Injection bolt (3): Earth (5): Tube (9): Foaming chemical solution for sealing

Claims (1)

[Scope of Claims] 1. Both ends of a tube made of fabric are fixed to the outer circumferential surface of a hollow injection bolt, the injection bolt is inserted into a predetermined hole drilled in advance in a ground or a base, and then the tube is A seal packer construction method for injection bolts, which is characterized by injecting a foamed hardening resin into the injection bolt and tightly sealing the gap between the injection bolt and the ground or base. 2. The seal packer construction method according to claim 1, wherein the fabric has breathability, strength to withstand water pressure, and appropriate watertightness. 3. A claim in which the fabric is a single layer or two or more layers of knitted fabrics, woven fabrics, nonwoven fabrics, felts, or nets made of natural fibers, chemical fibers, synthetic fibers, or inorganic fibers singly or in combination. The seal packer construction method described in 1. 4. The seal packer construction method according to claim 2 or 3, wherein the fabric is made of resin-treated fibers. 5.Claim 1, wherein the foamed curable resin is a urethane resin.
The seal packer method described.