KR102106034B1 - Multistage steel pipe grouting method for tunnel construction - Google Patents

Abstract

The present invention relates to a multi-stage steel pipe grouting method for tunnel construction. The multi-stage steel pipe grouting method for the tunnel construction according to one embodiment of the present invention includes the following steps of: perforating a plurality of insertion holes along the advancing direction of a tunnel; inserting a tube into each of the plurality of insertion holes; caulking an inlet of the tube; injecting a sealing material into a space between the tube and the insertion hole; curing the sealing material; injecting grout into the ground around the tube through a packer inserted inside the tube; and curing the grout. At this time, in the step of curing the grout material, rapid curing is performed by heating the grout material.

Description

Multi-stage steel pipe grouting method for tunnel construction {MULTISTAGE STEEL PIPE GROUTING METHOD FOR TUNNEL CONSTRUCTION}

The present invention relates to a multi-stage grouting method for tunnel construction, and more particularly, to a multi-stage grouting method capable of reducing the grouting process and the tunnel construction work time by rapidly curing the grout material.

In general, auxiliary methods are used to ensure stability when excavating tunnels. In particular, in the case of low strength or low self-reliance or soft ground, an auxiliary method for reinforcing the ground around the tunnel should be implemented to prevent the collapse of the ground and surrounding structures.

As an auxiliary method for reinforcing the ground, a steel pipe multi-stage grouting method, a FRP (Fine Reinforced Plastic) multi-stage grouting method, and the like are known. Steel pipe multi-stage grouting method and FRP multi-stage grouting method are methods of arranging and installing steel pipes and FRP pipes around them before excavating tunnels, and injecting and solidifying grout materials in multiple stages into the ground through packers installed inside the steel pipes and FRP pipes. to be. According to the steel pipe multi-stage grouting method and the FRP multi-stage grouting method, the steel pipe and the FRP pipe and the ground are integrally formed, and the load applied to the tunnel is distributed by the beam action of the steel pipe and the FRP pipe and the surrounding ground to secure stability.

On the other hand, in the steel pipe multi-stage grouting method and FRP multi-stage grouting method, a curing process is required to fix the grout material after injection. In addition, before the grout material is injected, a sealing material is injected to seal the space between the steel pipe and the FRP tube and the insertion hole, and the sealing material also needs a curing process like the grout material.

In the current steel pipe multi-stage grouting method and FRP multi-stage grouting method, it takes about 48 hours to cure the grout material and the sealing material. In the process of curing the grout material and the sealing material, the process is stopped. However, if it takes a long time to cure the grout material and the sealing material, the loss due to the process interruption is not small. Accordingly, in order to reduce curing time, development of a sealing material is also being developed, but it is difficult to apply to an actual site due to problems such as workability.

Registered Patent Publication No. 1819089 (January 10, 2018)

The present invention is to solve the above-mentioned problems of the prior art, it is an object to provide a multi-stage grouting method that can reduce the curing time of the grouting material or sealing material in performing a multi-stage grouting method for tunnel construction.

In addition, the object of the present invention is to provide a multi-stage grouting method capable of quickly and uniformly curing the grouting material or the sealing material.

The multi-stage grouting method for tunnel construction according to an embodiment of the present invention includes: drilling a plurality of insertion holes along a traveling direction of a tunnel, inserting a tube into each of the plurality of insertion holes, and caulking the inlet of the tube Step, injecting a sealing material into the space between the tube and the insertion hole, curing the sealing material, injecting the grout material into the ground around the tube through a packer inserted in the tube, and curing the grout material . At this time, in the step of curing the grout material, rapid curing is performed by heating the grout material.

According to an embodiment of the present invention, in the step of curing the sealing material, rapid curing may be performed by heating the sealing material.

According to an embodiment of the present invention, in the step of curing the grout material, the grout material may be heated by heating the tube to transfer heat to the grout material. At this time, the tube can be heated by passing a current through the tube. Specifically, current can flow through the tube by connecting electric wires to one end and the other end of the pipe inserted into the insertion hole and connecting the electric wires to a power source.

According to an embodiment of the present invention, in the step of curing the grout material, power can be connected to the soil around the insertion hole and current is passed to heat the soil, and heat can be transferred to the grout material through the soil.

According to an embodiment of the present invention, a temperature sensor may be installed adjacent to the tube, and in the step of curing the grout material, the curing time of the grout material may be adjusted by controlling the heating degree of the grout material with reference to the temperature sensor.

According to one embodiment of the invention, the tube may be a steel tube or a fiber reinforced plastic (FRP) tube.

According to an embodiment of the present invention, the curing time may be reduced by injecting the grouting material or the sealing material, and then heating it, thereby significantly reducing the multi-stage grouting process and the entire tunnel construction time.

In addition, according to an embodiment of the present invention, rapid curing can be achieved by heating the tube to transfer heat to the grout material, and at this time, the entire tube is evenly heated to ensure uniform strength by a multi-stage grouting process. have.

1 is a schematic diagram showing a state in which a multi-stage grouting steel pipe for tunnel construction is installed according to an embodiment of the present invention.
2 is a flowchart sequentially showing a multi-stage grouting method according to an embodiment of the present invention.
3 is a view sequentially showing a multi-stage grouting process according to an embodiment of the present invention.
4 is a view schematically showing a configuration for rapidly curing a sealing material and a grout material according to an embodiment of the present invention.

Hereinafter, preferred 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 can easily implement them.

In order to clearly describe the present invention, descriptions of parts not related to the present invention are omitted, and like reference numerals are assigned to the same components throughout the specification. In addition, the size, thickness, location, and the like of each component shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to what is illustrated. That is, specific shapes, structures, and characteristics described in the specification can be implemented by changing from one embodiment to another without departing from the spirit and scope of the present invention, and the position or arrangement of individual components is also the spirit of the present invention. And it should be understood that it can be changed without departing from the scope.

Therefore, the detailed description to be described later is not intended to be taken in a limiting sense, and the scope of the present invention should be taken as encompassing the scope claimed by the claims and all equivalents thereto.

1 is a front view and a side cross-sectional view showing a state in which a multi-stage grouting steel pipe is installed for tunnel construction according to an embodiment of the present invention.

Referring to FIG. 1, the steel pipe 120 is buried in the insertion hole 110 formed along the circumference of the tunnel 100 to be excavated, and the steel pipe 120 and the ground 10 are integrated by injection and fixation of grout material. do.

The insertion hole 110 may be perforated around the tunnel 100, a steel pipe 120 is buried in each insertion hole (110). The number, spacing, and arrangement of the steel pipes 120 buried and grouted in the ground 10 are not limited to those shown, and may be determined according to the size of the tunnel 100 and the type and strength of the ground.

The steel pipe 120 may be formed with a plurality of ejection holes (not shown) so that the grout material injected into the steel pipe 120 can be diffused to the surrounding ground. In addition, a shoe (not shown) having a substantially conical shape in which the connecting portion with the steel pipe 120 has a larger diameter than the steel pipe 120 and decreases in diameter toward the tip of the steel pipe 120 may be installed. Here, the diameter of the shoe at the connection portion with the steel pipe 120 (that is, the maximum diameter of the shoe) may have a size such that the fitting is fixed when the steel pipe 120 is inserted into the insertion hole 110. The shoe facilitates the introduction of the steel pipe 120 when installing the steel pipe 120 in the insertion hole 110, and serves to separate the steel pipe 120 from the bottom surface of the insertion hole 110 after the steel pipe 120 is inserted.

2 is a flowchart sequentially showing a multi-stage grouting method according to an embodiment of the present invention, and FIG. 3 is a diagram sequentially showing a multi-stage grouting process according to an embodiment of the present invention. The present invention has been devised to significantly reduce the process time in the multi-stage grouting process for tunnel construction as described above, and the multi-stage grouting method according to an embodiment of the present invention will be described in detail below with reference to FIGS. 2 and 3. do.

First, the insertion hole 110 is drilled around the position to excavate the tunnel (S110). Perforation of the insertion hole 110 may be made using a blow-type drilling equipment such as a pneumatic drill. When drilling the insertion hole 110, it is possible to collect the slime and grasp the lipid state therefrom.

In this embodiment, as shown in Figure 3 (a), the insertion hole 110 is drilled to have a predetermined inclination upward from the horizontal direction, but it is possible to punch the insertion hole 110 in the horizontal direction as possible desirable. Insertion hole 110 may be formed in a number of umbrella-shaped around the location to excavate the tunnel, the number and arrangement of the insertion hole 110 may be determined according to the size and type of the tunnel, the strength of the ground. In addition, the diameter and length of the insertion hole 110 may be determined according to the size and length of the inserted steel pipe.

Subsequently, the steel pipe 120 is inserted into the insertion hole 110 (S120). At this time, the injection hose 130 for injecting the sealing material between the steel pipe 120 and the insertion hole 110 may be disposed together (see FIG. 3 (b)). The material, diameter, etc. of the steel pipe 120 may be determined according to the strength to be obtained through a multi-stage grouting process. Further, the steel pipe 120 may be used by connecting a plurality of short pipes in consideration of constructability.

Thereafter, caulking is performed between the steel pipe 120 and the insertion hole 110 around the entrance of the insertion hole 110 (S130). As shown in Figure 3 (c), caulking is carried out at a predetermined distance from the tunnel excavation surface, through which the airtightness between the steel pipe 120 and the insertion hole 110 is maintained, and the sealing material and the grout material are leaked. Can be prevented. In this embodiment, the foaming urethane and cement may be used as the caulking material 140, but the present invention is not limited thereto.

After caulking, the sealing material 150 is injected into the space between the steel pipe 120 and the insertion hole 110 (S140). Specifically, as shown in (d) of FIG. 3, when the steel pipe 120 is inserted, the injection hose 130 disposed together is connected to the sealing material injection plant, and the steel pipe 120 is provided through the injection hose 130. The sealing material 150 is injected into the space between the outer wall and the inner wall of the insertion hole 110. In this embodiment, the bentonite and the cement are mixed with water as the sealing material 150, but it is also possible to change to other known materials.

After the sealing material 150 is injected, the sealing material 150 is cured (S150). In the case of the sealing material 150 used by mixing bentonite and cement with water, it solidifies through a curing time of about 24 hours and is transformed into a gel state. If sufficient curing is not achieved, there is a problem that the grout material is not sufficiently injected into the ground clearance when the subsequent grout material is injected. However, as described above, since the multi-stage grouting process is stopped during the curing time, the time required for the entire tunnel construction increases, so it is necessary to reduce the curing time.

In one embodiment of the present invention, rapid curing is performed to solve this problem. For example, after the sealing material 150 is injected, the steel pipe 120 is heated and heat is transferred to the sealing material 150 through this, thereby shortening the curing time. The specific method of rapid curing and its configuration will be described later.

After curing of the sealing material 150, the grout material 160 is injected into the ground 10 around the steel pipe 120 (S160). As shown in Figure 3 (e), to install the packer 170 in the steel pipe 120 in order to inject the grout material 160 and connects it to the grout material injection plant, the packer 170 is a hydraulic packer Alternatively, a rubber packer can be used. The packer 170 may be installed at regular intervals in the steel pipe 120, and the installation interval may be determined in consideration of characteristics of the ground (eg, permeability coefficient, jointing properties, etc.).

When the grout material 160 is injected in multiple stages through the packer 170, the injected grout material 160 is diffused to the surrounding ground outside the steel pipe 120 through a plurality of ejection holes formed on the side wall of the steel pipe 120. . Ejection holes may also be formed in the shoe installed at the tip of the steel pipe 120, and through this, the grout material 160 may be ejected and diffused into the surrounding ground.

As the grout material 160, cement milk and soda silicate made by mixing cement and water can be used, and the mixing ratio of cement milk, the mixing ratio with soda silicate, and the like can be determined according to ground characteristics. Of course, other known materials can be used as the grout material 160.

After injecting the grout material 160, the grout material 160 is cured (S170). In the related art, a long time of about 24 hours was required for curing after injecting the grout material 160. However, the multi-stage grouting process is interrupted during the curing time of the grout material 160 to increase the time required for the entire tunnel construction, so in order to solve this problem, rapid curing is performed in one embodiment of the present invention. Specifically, as described later, the steel pipe 120 may be heated after the grout material 160 is injected, and heat is transferred to the grout material 160 through the steel pipe 120 to significantly reduce curing time. You can.

Various methods may be used to heat the steel pipe 120 for rapid curing of the sealing material 150 and the grout material 160 described above. For example, according to an embodiment of the present invention, the steel pipe 120 can be directly heated by passing an electric current to the steel pipe 120. Hereinafter, a configuration for this will be described with reference to the drawings.

4 is a view schematically showing a configuration for rapidly curing a sealing material and a grout material according to an embodiment of the present invention.

Referring to FIG. 4, the steel pipe 120 may be heated by assembling electric wires 180 at both ends and rear ends of the steel pipes 120 and connecting the electric wires 180 to a power source to flow current. The wire 180 may be assembled to the steel pipe 120 in various ways, such as welding and screw coupling, inside the steel pipe 120. When the electric wire 180 is connected to both ends of the steel pipe 120 and current flows, the steel pipe 120 may be heated by acting as a resistance, through which heat is transferred to the sealing material 150 or the grout material 160 to rapidly Curing can be achieved.

When the current flows through the steel pipe 120 as described above, the steel pipe 120 may be uniformly heated, and the grouting material injected and diffused into the sealing material 150 injected outside the steel pipe 120 or the ground around the steel pipe 120. By uniformly transferring heat to 160), it can be uniformly solidified and hardened to ensure uniform strength.

When a current flows through the steel pipe 120, the steel pipe 120 may be heated to a maximum of 700 to 800 ° C. In this embodiment, the temperature at which the steel pipe 120 is heated according to the time of passing the current through the steel pipe 120 It can be controlled, and through this, the curing time of the sealing material 150 or the grout material 160 can be adjusted.

To this end, a temperature sensor (not shown) may be installed adjacent to the steel pipe 120. For example, the temperature sensor may be attached and installed on the inner surface of the steel pipe 120. When a temperature sensor is installed, the temperature of the steel pipe 120 can be checked through this, and the heating material of the steel pipe 120 is controlled by controlling the voltage applied to the electric wire 180 with reference to the sealing material 150 or The curing time of the grout material 160 can be adjusted.

As described above, in an embodiment of the present invention, in the process of curing the sealing material 150 and the grout material 160, a current is flowed through the steel pipe 120 to heat and heat is transferred to the sealing material 150 or the grout material 160 Rapid curing can be performed in this manner to reduce curing time. Accordingly, the multi-stage grouting process and the entire tunnel construction time can be reduced, and by heating the entire steel pipe evenly, the strength of the sealing material and the grout material can reach a desired level within a short time, thereby securing the stability of the tunnel construction. In addition, by controlling the heating temperature of the steel pipe, the curing time can be adjusted to further advance the process.

Meanwhile, in the above-described embodiment, the steel pipe multi-stage grouting process has been exemplified and described, but the same method may be applied to a fiber reinforced plastic (FRP) multi-stage grouting process.

FRP pipes have a higher bending stiffness and lighter weight than steel pipes, making them easy to install and corrosion-resistant.In the FRP multi-stage grouting process using this, similar to the steel pipe polysaccharide grouting process, the sealing material is injected and fixed between the FRP pipe and the insertion hole. After that, grout material is injected using a packer. In addition to cement milk and soda silicate, a grouting material in the FRP multi-stage grouting process may be used by further mixing, and other known materials may be used.

However, unlike the steel pipe, since the FRP pipe cannot be directly heated by passing an electric current, the FRP multi-stage grouting process heats the sealing material or the grout material in different ways.

For example, using the fact that the soil around the insertion hole where the FRP pipe is buried has a constant resistance, when power is applied to the soil around the insertion hole and a voltage is applied, the soil is heated and the adjacent sealing material or grout Heat can be transferred to the ash. The soil contains moisture, and the moisture contained in it evaporates as the soil heats up. Accordingly, the heating temperature of the soil may rise to about 100 ° C. at which moisture is evaporated.

As described above, in the case of heating by flowing an electric current through the soil, the heating temperature is somewhat limited, but heat can be transferred to the grouting material or adjacent sealing material diffused in the soil to realize a desired rapid curing. Accordingly, the grouting process and The entire tunnel construction time can be saved.

Although the present invention has been described by specific matters such as specific components and limited embodiments, the above embodiments are provided to help the overall understanding of the present invention, and the present invention is not limited thereto, and the present invention Those skilled in the art can make various modifications and variations from these descriptions.

For example, in one embodiment of the present invention, it was described that both the sealing material and the grout material are rapidly cured, but it is also possible to selectively rapidly cure any one of them. In addition, the steel pipe multi-stage grouting process was described as directly heating the steel pipe for rapid curing.However, in the steel pipe multi-stage grouting process, when it is difficult to flow current through the steel pipe, such as the inability to connect an electric wire within the steel pipe, the method of heating the soil around the steel pipe As it will be possible to transfer heat to the sealing material or grout material.

Therefore, the spirit of the present invention is not limited to the above-described embodiments, and should not be determined, and all claims that are equally or equivalently modified with respect to the claims to be described later belong to the scope of the spirit of the present invention. something to do.

100: tunnel
110: insertion hole
120: steel pipe
130: injection hose
140: caulking
150: sealing material
160: grout material
170: Packer
180: wire

Claims (8)

As a multi-stage steel pipe grouting method for tunnel construction,
Drilling a plurality of insertion holes along the direction of the tunnel,
Inserting a steel pipe into each of the plurality of insertion holes,
Caulking the inlet of the steel pipe,
Injecting a sealing material in the space between the steel pipe and the insertion hole,
Curing the sealing material,
Injecting a grout material into the ground around the steel pipe through a packer inserted in the steel pipe, and
Curing the grout material
Including,
Before inserting the steel pipe into the plurality of insertion holes, the wires are assembled and connected to one end and the other end of the steel pipe, respectively.
In the step of curing the sealing material and the step of curing the grout material, rapid curing is performed by heating the sealing material and the grout material, respectively, and the sealing material and the grout are respectively heated so that the steel pipe acts as a resistor and is uniformly heated. After injecting ash, power is supplied to the electric wire to flow current, and heat is transferred from the steel pipe to the sealing material and the grout material,
Adjusting the curing time of the sealing material and the grout material by controlling the temperature at which the steel pipe is heated through the time of passing current through the electric wire,
Multistage steel pipe grouting method. delete delete delete delete According to claim 1,
In the step of curing the grout material, the power is connected to the soil around the insertion hole, and a current is passed to heat the soil, and heat is transferred to the grout material through the soil. According to claim 1,
A temperature sensor is installed adjacent to the steel pipe, and in the step of curing the grout material, the curing time of the grout material is controlled by controlling the heating degree of the grout material with reference to the temperature sensor.
delete

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