KR20200047881A - Simultaneous injection method of permeation grouting for reinforcing tunnel using outer packer - Google Patents

Abstract

Provided is a simultaneous injection method of permeation grouting for tunnel reinforcement using outer packers, which is a waterproofing and reinforcing grouting method for enhancing the stability of a tunnel face when excavating a tunnel in soft ground and ground with excessive water infiltration. The simultaneous injection method uses a plurality of detachable outer packers that are elastomer-based corrugated elastic packers to perform efficient and quick grouting in the ground. In addition, the simultaneous injection method, after installing a plurality of detachable outer packers on the outer circumferential surface of a steel pipe and forming partitions between the outer packers, simultaneously performs permeation grouting without sealant insertion and backflow prevention valve installation as in the existing method so as to reinforce the ground and maximize the waterproofing effect.

Description

Simultaneous injection method for tunnel reinforcement using external packer {SIMULTANEOUS INJECTION METHOD OF PERMEATION GROUTING FOR REINFORCING TUNNEL USING OUTER PACKER}

The present invention relates to a co-injection grouting method, and more specifically, as an ordering and reinforcing grouting method for enhancing the stability of a membrane surface when excavating a tunnel in a soft ground or an excessively inflowed soil, using a plurality of removable external packers It relates to a method of simultaneous injecting grouting for tunnel reinforcement using an external packer that can perform grouting in the ground.

In general, underground and drilling spaces are secured by excavating the ground, which is mainly composed of soil or rock. At this time, if the ground that constitutes the excavation surface is not stable, excavation cannot be performed because it contains dangers such as collapse. do.

Particularly, when the ground where the excavation is scheduled to proceed has a lot of soil or weathering, or if the rock quality is poor due to the development of joints, stratification, and fractures, the excavation must be carried out while adequately reinforcing due to excessive deformation or collapse during excavation. do.

Therefore, in excavation, it is necessary to reinforce or reinforce in various ways so that the underground and drilling spaces are stable.Nailing, rock bolt, anchor, steel pipe multi-stage grouting method, etc. are used in this method. have.

Tunnel construction or incision drilling is a typical construction to apply the underground and excavation space reinforcement method. In particular, the tunnel top is the most easily exposed to the risk of collapse when excavating during tunnel construction.

In addition, when the excavation surface is poor during excavation, rock bolts and nailing methods that are commonly used are often installed at a slightly downward angle. On the other hand, in the case of steel pipe multi-stage grouting, which is mainly used for reinforcing the upper part of the tunnel, unlike the reinforcement on the cut slope, the grout is used when grouting between the reinforcement and the perforation hole because the end of the reinforcement must be installed upward from the excavation surface. There is a reflux problem. In order to solve this problem, a back flow of grout is prevented by using a packer or caulking material. That is, when the ground reinforcement is performed, the steel pipe reinforcement multi-step grouting method is used when not only the reinforcement by the reinforcement material inserted in the perforation hole but also the grouting effect of the ground around the tunnel wall is required.

On the other hand, in the multi-stage grouting method of steel pipe, after the perforation, the steel pipe is inserted, the entrance of the perforated hole is sealed with a caulking material, and the sealer is sealed between the steel pipe and the perforated hole, and then a packer is installed inside the steel pipe to move the packer in multiple stages. It is a method of performing. Such a steel pipe reinforced multi-stage grouting method can simultaneously obtain a ground reinforcement effect by a steel pipe and an order effect by grouting.

The steel pipe reinforced multi-stage grouting method according to the prior art is generally used for ordering and reinforcing the soft weathered rock layer by proceeding in the order of perforation, steel pipe insertion, caulking and sealing, and grouting.

Specifically, the perforation process is performed by using a casing rod when the perforation hole collapses, otherwise it is also possible to perforate a regular rod. Next, the insertion of the steel pipe, in the case of a casing rod, removes the casing after inserting the steel pipe. Next, the caulking of the perforated inlet is carried out to prevent the inflow of groundwater and the backflow of the grouting material. At this time, the sealing of the periphery of the steel pipe uses a product that exhibits a sufficient sealing effect without reducing the volume of the sealing material. Then, the multi-stage grouting material is injected step by step according to the injection length determined according to the ground conditions.

1 is a cross-sectional view illustrating a steel pipe multi-stage grouting method according to the prior art, and FIG. 2 is an operation flow diagram showing a steel pipe multi-stage grouting method according to the prior art.

Referring to Figure 1, the steel pipe multi-stage grouting method according to the prior art includes a caulking portion 11, a sealing material injection and discharge hose 12, a steel pipe 13 and a sealing material 14, such a conventional grouting method The caulking is performed by the caulking portion 11 to prevent the grouting material from flowing back to the ground. However, this has a problem in that the actual caulking is not performed, and thus a countercurrent of the grouting material through the borehole is generated, and eventually the ground is not efficiently reinforced.

Specifically, referring to Figure 2, the steel pipe multi-stage grouting method according to the prior art, a) step of drilling the ground (S10), b) step of inserting a steel pipe with an injection hole at regular intervals into the hole ( S20); c) performing caulking between the outer wall of the rear end of the steel pipe and the perforation hole to prevent leakage of groundwater, leakage of soil and backflow of the injection material (S30); d) injecting a sealing material between the outer wall of the steel pipe and the perforation hole so as to be injected only in a limited range while preventing backflow of the injection material (S40); e) installing a packer inside the steel pipe (S50); And f) injecting the grouting material through the injection hole set by the packer (S60).

The steel pipe multi-stage grouting method according to the prior art uses a grouting material to provide an ordered effect, as well as to excavate by dispersing the earth pressure and supporting the upper load by forming the integrated beam structure to have the flexural rigidity of the steel pipe and its surrounding soil. It can be said to be a very structurally advantageous method in that it improves the structural stability of the cotton.

By the way, the sealing material injected between the outer wall of the steel pipe and the perforated hole does not leave space due to the expansion of the volume, and the cohesive strength is not too high, so the cement material and bentonite are mixed and specially manufactured so that the injection material can penetrate the sealing material and spread widely in the ground. In order to exert the above function, a solidification time of about 24 hours is required, and there is a problem in that the construction period is prolonged because the injection material is sequentially injected into each compartment partitioned by the packer.

On the other hand, the steel pipe multi-step method, which is applied to stabilize the membrane during tunnel excavation, excavates a perforation hole in the upper crown of the membrane and inserts a steel pipe, and then injects a grouting material to improve the order and ground reinforcement of the groundwater flowing into the tunnel. I can plan it.

The multi-stage steel pipe construction method, which is applied as an auxiliary method for such tunnels, is a method of minimizing the inflow of groundwater and solidifying the ground by grouting and simultaneously enhancing the soil by inserting steel pipes on the entire upper surface of the membrane.

As a prior art related to the above-mentioned steel pipe multi-step construction method, Korean Patent Registration No. 10-1785061 discloses an invention titled "Grotting method using steel pipe and grout injection device therefor", see FIGS. 3 and 4 Will be explained.

Figure 3 is a cross-sectional view showing a grout injection device using a steel pipe according to the prior art, Figure 4 is a cross-sectional view showing a construction example of a grouting method using the grout injection device shown in FIG.

Referring to Figures 3 and 4, the grouting injection device using a steel pipe according to the prior art, the first solution and the second solution is mixed grouting material into the perforated hole 20 formed at a predetermined depth on the ground As a grout injection device for doing this, it includes a head portion 40, a steel pipe portion 50, a hollow pipe 60 and a partition member 53.

The head portion 40 is a tubular body having a first connector 41 through which a supply pipe for supplying a first liquid is coupled, and a second connector 42 through which a supply pipe for supplying a second liquid is coupled. Is done.

The steel pipe portion 50 is assembled with the head portion 40, extends into the perforation hole 20, and is screwed to the front portion of the steel pipe body 51 and the steel pipe body 51 communicating with the head portion 40 The mixing chamber 52 is provided.

The inner tube 60 is inserted to extend from the inside of the head portion 40 to the inside of the steel pipe portion 50.

The partition member 53 is interposed in the steel pipe portion 50 to determine the length of the mixing chamber 52, and a plurality of inflow holes for introducing the second liquid into the mixing chamber 52 are provided around the center.

Specifically, the inner tube 60 is an inlet is in communication with the first connector 41 and the outlet is disposed in communication with the mixing chamber 52, the space between the steel pipe portion 50 and the inner tube 60 is the second connector After communicating with (42), the first liquid supplied through the first connector 41 and the second liquid supplied through the second connector are mixed in the mixing chamber 52 and then out of the mixing chamber 52 Ejected and penetrated into the ground, the inner tube 60 is inserted into the head portion 40, the rear portion communicating with the first connector 41, and penetrates through the center of the partition member 53, the mixing chamber 52 ) It is inserted into the inside and includes a front portion fixed to the center of the partition member 53, and the rear portion and the front portion of the inner tube 52 are assembled to be coupled and separated from each other. Here, reference numeral 30 denotes a caulking portion, reference numeral 52a denotes a discharge hole, reference numeral 54 denotes a backflow prevention valve, reference numeral 55 denotes a spacing member, and reference numeral 63 denotes an O-ring, respectively.

As shown in Figure 4, the grouting method using a grout injection device using a steel pipe according to the prior art, the process of forming a perforated hole 20 at a predetermined interval and depth on the ground; A process of inserting a grout injection device having a coaxial double tube structure in which the inner tube 60 is inserted into the perforation hole 20; Caulking (caulking) between the inlet of the perforation hole 20 and the grout injection device; And injecting the first grouting material through the mixing chamber 52 inside the perforation hole 20 by injecting the first liquid and the second liquid into the head portion 40.

According to the grout injection device using a steel pipe according to the prior art, since it is possible to mix the first liquid containing the quick-setting agent with the second liquid at the far end of the steel pipe, rapid dissolution such as elution and leakage located at the deep point of the perforation hole There is an advantage that the ground reinforcement construction can be performed by injecting a grouting material having a short gelation time with respect to the required portion. In the case of the existing steel pipe multi-stage grouting method, in the case of a ground with a lot of groundwater leakage, additional order grouting is required, but the present invention does not require such an additional process. In addition, since it is possible to perform reinforcement and order grouting construction by using a steel pipe of a single body, construction is easy, and unlike the conventional grouting method, a sealing material is not required, thereby reducing material cost and labor.

However, in the case of a grout injection device using a steel pipe according to the prior art, as a method of fundamentally removing the sealing material for tight injection of the grouting material, rapid construction is possible, but grouting in the perforation hole by simultaneous injection of the grouting material and input of a hardening material There is a problem that the possibility of premature curing of the ash is concerned.

Republic of Korea Patent No. 10-1785061 (application date: July 19, 2016), the name of the invention: "grouting method using a steel pipe and grout injection device therefor" Republic of Korea Patent No. 10-1070072 (application date: February 15, 2011), the name of the invention: "Multi-layer simultaneous grouting device using double packer and construction method therefor" Republic of Korea Patent No. 10-1541718 (application date: February 10, 2015), the name of the invention: "non-sealed grouting method using a double packer grouting device" Republic of Korea Registered Patent No. 10-1528524 (application date: March 4, 2015), the name of the invention: "A grouting device having a pressurized double packer and a grouting construction method using the same" Republic of Korea Patent No. 10-807258 (application date: May 10, 2006), the name of the invention: "multi-pack steel pipe simultaneous injection device and grouting construction method using the same"

The technical problem to be achieved by the present invention for solving the above-mentioned problems is an order and reinforcement grouting method for enhancing the stability of a membrane surface when tunnel excavation in a soft ground or an excessively inflowed soil, as an elastomer-based corrugated elasticity The present invention is to provide a method for simultaneous penetration grouting for tunnel reinforcement using an external packer, which can efficiently and quickly perform grouting in the ground using a plurality of removable external packers that are packers.

Another technical problem to be achieved by the present invention, by installing a plurality of removable outer packers on the outer circumferential surface of the steel pipe to form a partition between each outer packer, it is possible to simultaneously perform the penetration grouting without installing the existing sealing material and installing the backflow prevention valve, It is to provide a method of simultaneous injection grouting for tunnel reinforcement using an external packer.

As a means for achieving the above-described technical problem, the tunneling penetration grouting co-injection method using an external packer according to the present invention, in the tunnel reinforcement penetration grouting co-injection method for reinforcement and reinforcement of the ground, a) a steel pipe Excavating a hole for insertion; b) mounting a plurality of outer packers on the outer circumferential surface of the steel pipe using an outer packer fixing device; c) forming a discharge hole for injecting a grouting material in the steel pipe, and welding a plurality of spacers for maintaining a gap on an outer circumferential surface of the steel pipe; d) inserting the steel pipe into the perforated hole; e) caulking the opening of the perforation hole with a caulking material; And f) performing sequential injection or simultaneous injection of penetration grouting through one or a plurality of hollow pipes inserted into the steel pipe, wherein the plurality of external packers are detachable elastic material insulating materials inside the perforated hole. It is characterized by forming a plurality of partition walls at regular intervals on the outer peripheral surface of the steel pipe.

Here, the outer packer of step b) is an elastomeric corrugated elastic packer, and may be formed in a circular shape and an oval shape of various angles to form a closed partition structure despite the weight of the steel pipe.

Here, it is preferable that the outer packer of step b) is made about 10% larger than the perforation diameter for forming the perforation hole to prevent backflow of the grouting material.

Here, one of the plurality of external packers in step b) may be installed at the front end of the steel pipe to allow the grouting material to be injected into the front surface of the steel pipe.

Here, the outer packer fixing device of step b) may be a pair of hose bands fixing both sides of each outer packer to the outer circumferential surface of the steel pipe 110.

Here, the spacer of step c) is installed at regular intervals on the outside of the steel pipe or around the outer packer to prevent the outer packer from being deformed by the weight of the steel pipe, and is pinched within the perforation of the spacer. In order to prevent the phenomenon, it is preferable that the size of the spacer is made smaller than the aperture diameter.

According to the present invention, as a method of ordering and reinforcing grouting for enhancing the stability of a membrane surface during tunnel excavation in a ground with excessive soft ground and inflow water, efficient and rapid use of a plurality of removable outer packers which are elastomeric corrugated elastic packers Grouting can be performed in the ground.

According to the present invention, a plurality of removable outer packers are installed on the outer circumferential surface of the steel pipe to form a partition between each outer packer, and the penetration of the existing sealing material and penetration grouting without the installation of a backflow prevention valve are simultaneously performed to strengthen the ground and maximize the order effect. can do.

1 is a cross-sectional view for explaining a steel pipe multi-stage grouting method according to the prior art.
Figure 2 is a flow chart showing the steel pipe multi-stage grouting method according to the prior art.
Figure 3 is a cross-sectional view showing a grout injection device using a steel pipe according to the prior art.
4 is a cross-sectional view showing a construction example of the grouting method to which the grout injection apparatus shown in FIG. 3 is applied.
5 is an operation flow chart showing a simultaneous injection method for penetration grouting for tunnel reinforcement using an external packer according to an embodiment of the present invention.
6 is a view showing the outer packer in the co-injection grouting method for tunnel reinforcement using an outer packer according to an embodiment of the present invention.
7 is a view illustrating the prevention of deformation of the outer packer in the co-injection method of penetration grouting for tunnel reinforcement using an outer packer according to an embodiment of the present invention.
8 is a cross-sectional view showing that the outer packer is fastened to the steel pipe in the co-injection grouting method for tunnel reinforcement using an outer packer according to an embodiment of the present invention.
9 is a view illustrating a hose band that is an external packer fixing device in a co-injection grouting method for tunnel reinforcement using an external packer according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part “includes” a certain component, this means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

[Co-injection grouting method for tunnel reinforcement using external packer 120]

5 is an operation flow diagram showing a co-injection grouting method for tunnel reinforcement using an external packer according to an embodiment of the present invention, and FIG. 6 is a co-injection grouting method for tunnel reinforcement using an external packer according to an embodiment of the present invention As a cross-sectional view for explaining, it is a view specifically illustrating an outer packer.

5 and 6, the co-injection grouting method for tunnel reinforcement using an external packer according to an embodiment of the present invention is a co-injection co-injection method for tunnel reinforcement for order and reinforcement of the ground 210, First, a drilling hole (h) for inserting the steel pipe 110 is excavated (S110).

Next, a plurality of external packers 120 are mounted on the outer circumferential surface of the steel pipe 110 using the external packer fixing device 130 (S120). Here, the outer packer 120 is, as shown in the lower portion of Figure 6, as an elastomer (Elastomer) series of corrugated elastic packer, also, as shown in Figure 7 to be described later, the weight of the steel pipe 110 Nevertheless, it may be formed in a circular shape or an oval shape of various angles to form a closed partition structure. At this time, the outer packer 120 is preferably made about 10% larger than the perforation diameter for forming the perforated hole (h) to prevent the backflow of the grouting material (220).

In addition, as shown by reference numeral D in FIG. 6, one of the plurality of outer packers 120 may be installed at the front end of the steel pipe 110 to enable injection of grouting material in front of the steel pipe 110. have.

In addition, the outer packer fixing device 130, as shown in FIGS. 8 and 9 to be described later, a pair of hose bands fixing both sides of each outer packer 120 to the outer peripheral surface of the steel pipe 110 ( Hose Band), but is not limited thereto.

Next, a discharge hole 111 for injecting the grouting material 220 in the steel pipe 110 is formed, and a plurality of spacers 140 for maintaining a gap on the outer circumferential surface of the steel pipe 110 are welded (S130). Here, the spacer 140 is installed at regular intervals on the outside of the steel pipe 110 to prevent the external packer 120 from being deformed by the weight of the steel pipe 110, or the external packer 120 As a spacer installed around, it is preferable that the size of the spacer 140 is made smaller than that of the aperture so as to prevent the spacer 140 from being pinched within the aperture.

Next, the steel pipe 110 is inserted into the hole (h) (S140).

Next, the opening of the perforation hole (h) is caulked with a caulking material 150 (S150).

Next, sequential injection or simultaneous injection of permeation grouting is performed through one or more hollow pipes 160 inserted into the steel pipe 110 (S160).

Accordingly, the plurality of outer packers 120 is a separating material of a removable elastic material, and a plurality of partition walls are formed at regular intervals on the outer circumferential surface of the steel pipe 110 inside the perforation hole h. As shown, it is divided into regions A, B, and C.

Infiltration grouting for tunnel reinforcement using an external packer according to an embodiment of the present invention, the injection of grouting material according to the use of sealing material applied for smooth injection of grouting material in the existing steel pipe multi-step construction method In order to overcome the disadvantages of deterioration, etc., after introducing a plurality of external packers 120, partition walls are formed at regular intervals to maximize the penetration effect due to injection of the grouting material 220, and also shorten the air and construction costs. ㅇ and can be saved.

On the other hand, Figure 7 is a view illustrating the prevention of deformation of the outer packer in the co-injection grouting method for tunnel reinforcement using an outer packer according to an embodiment of the present invention.

Specifically, the outer packer 120 is fixedly attached to the outer circumferential surface of the steel pipe 110 inserted into the perforated hole h, as shown in a) of FIG. 7, and b) and c of FIG. 7 As shown in), the outer packer 120 is formed in an oval shape (120a, 120b) of a circular or various angles to form a partition structure closed at predetermined intervals on the outer circumferential surface of the steel pipe 110, and FIG. 7 As shown in d), the oval outer packers 120a and 120b may be cross-installed, but is not limited thereto.

On the other hand, the co-injection method for tunnel grouting using an outer packer according to an embodiment of the present invention, without the use of an existing sealing material applied for smooth injection of grouting material, a number of inner tube 160 inside the steel pipe 110 and As a steel pipe multi-stage construction method that can be simultaneously injected by a plurality of external packers 120 outside the steel pipe 110, the external packer 120 is simple and quick by applying an insulating material of an elastic material without the use of additional injection material or expansion material. It is possible to inject grouting material.

8 is a cross-sectional view showing that the outer packer is fastened to the steel pipe in the co-injection grouting method for tunnel reinforcement using an outer packer according to an embodiment of the present invention.

The outer packer 120, as shown in FIG. 8, fixes an elastomeric corrugated elastic packer to the outside of the steel pipe 110 by using a pair of hose bands 130, and is provided in a perforated hole (h). After insertion, penetration grouting may be performed simultaneously using a plurality of hollow pipes 160 inserted into the steel pipe 110. At this time, the outer packer 120 is preferably made about 10% larger than the perforation diameter for forming the perforated hole (h) to prevent the backflow of the grouting material (220).

According to the embodiment of the present invention, since a single outer packer 120 having a simple structure is used, a partition wall having a predetermined interval can be constructed without installing additional packer pipes or springs, such as an existing outer packer. Therefore, rapid simultaneous injection is possible and cost can be reduced.

On the other hand, Figure 9 is a view illustrating an outer packer fixing device hose band in the co-injection grouting method for tunnel reinforcement using an outer packer according to an embodiment of the present invention.

As illustrated in FIG. 9, the outer packer fixing device 130 may use a pair of hose bands to attach the outer packer 120 to the steel pipe 110, but is not limited thereto.

After all, according to an embodiment of the present invention, as a method of ordering and reinforcing grouting for enhancing the stability of a membrane surface when tunnel excavation in a soft ground or an excessively inflowed soil, an efficient and rapid in-ground use of a plurality of removable outer packers It is possible to perform grouting, and by installing a number of removable external packers on the outer circumferential surface of the steel pipe to form a partition wall between each external packer, strengthening the ground by simultaneously performing penetration grouting without introducing the existing sealing material and installing the backflow prevention valve And maximize the order effect.

The above description of the present invention is for illustration only, and those skilled in the art to which the present invention pertains can understand that the present invention can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the above detailed description, and it should be interpreted that all changes or modified forms derived from the meaning and scope of the claims and equivalent concepts thereof are included in the scope of the present invention. do.

110: steel pipe
120: outer packer
130: hose band (external packer fixing device)
140: spacer (spacer)
150: caulking material
160: inner tube
111: grouting material discharge hole
210: ground
220: grouting material
h: punching hole

Claims (7)

In the co-injection method for the penetration reinforcement for tunnel reinforcement for the order and reinforcement of the ground 210,
a) excavating and forming a drilling hole (h) for inserting the steel pipe 110;
b) mounting a plurality of outer packers 120 to the outer circumferential surface of the steel pipe 110 using an outer packer fixing device 130;
c) forming a discharge hole 111 for injecting the grouting material 220 in the steel pipe 110 and welding a plurality of spacers 140 for maintaining a gap on an outer circumferential surface of the steel pipe 110;
d) inserting the steel pipe 110 into the hole (h);
e) caulking the opening of the hole (h) with a caulking material (150); And
f) a step of performing sequential injection or simultaneous injection of permeation grouting through one or more hollow pipes 160 inserted into the steel pipe 110,
The plurality of outer packers 120 are detachable elastic material insulating materials using outer packers, characterized in that a plurality of partition walls are formed at regular intervals on the outer circumferential surface of the steel pipe 110 inside the perforation hole (h). Simultaneous injection method of penetration grouting for tunnel reinforcement. According to claim 1,
The outer packer 120 of step b) is an elastomer-based corrugated elastic packer, which is formed in a circular shape or an oval shape of various angles to form a closed partition structure despite the weight of the steel pipe 110. Penetrating grouting method for tunnel reinforcement using an external packer. According to claim 2,
The outer packer 120 of step b) is reinforced with a tunnel using an outer packer, characterized in that it is made about 10% larger than the perforation diameter for forming the perforation hole (h) to prevent backflow of the grouting material 220 Dragon penetration grouting co-injection method. According to claim 2,
One of the plurality of external packers 120 in the step b) is installed in the front end of the steel pipe 110 to enable injection of grouting material in front of the steel pipe 110, for tunnel reinforcement using an external packer. Penetration grouting co-injection method. According to claim 1,
The external packer fixing device 130 of step b) uses a pair of hose bands that secures both sides of each external packer 120 to the outer circumferential surface of the steel pipe 110. Simultaneous injection method of penetration grouting for tunnel reinforcement. According to claim 1,
The spacer 140 of step c) is installed at regular intervals on the outside of the steel pipe 110 to prevent the external packer 120 from being deformed by the weight of the steel pipe 110 or the external packer ( 120) Simultaneous injection method of penetration grouting for tunnel reinforcement using an external packer, which is installed around. The method of claim 6,
Simultaneous injection method for penetration reinforcement for tunnel reinforcement using an outer packer, characterized in that the size of the spacer 140 is made smaller than that of the hole diameter to prevent the spacer 140 from being pinched within the hole diameter.

Images