KR100565866B1 - Inside hollow of abandoned structure filling method of construction using filling system and this - Google Patents

Abstract

The present invention is installed in the inner cavity of the structure of the hole hole or hole hole, fiber hose, etc., injecting the injection material into a specific area through the hole hole or hole hole, the fiber hose according to the internal cavity size, bending state, etc. It is an object of the present invention to provide a cavity filling system and a filling method using the same in order to fill the cavity tightly.

The present invention provides a method for filling an internal cavity of a waste structure using an injection material, the method comprising: digging or digging downward in an upper ground where the waste structure is installed to form an inlet; Drilling a plurality of inlets to a predetermined width in the waste structure in the same manner as forming the inlet; Installing a fibrous hose or a pore hose at the same time as installing a fibrous hose or a pore hose in the perforated waste structure and using an attachment ring at the upper end of the inner cavity of the perforated waste structure; Blocking a predetermined period in the perforated waste structure by using a partition, such as a pack or a brick, in the waste structure; By sequentially injecting the injection material into a predetermined region through the fibrous hose, the hole pipe, the hole hose, characterized in that the interior cavity of the waste structure tightly filled.

Waste structure, closed pipe, closed mine, internal cavity, filling system, filling method

Description

Inside hollow of abandoned structure filling method of construction using filling system and this}

1 is a state in which the joint structure filling system inside the waste structure according to the invention applied to the closed pipe

An illustration showing the

2 is applied to the abandoned mine internal cavity filling system according to the present invention

An illustration showing the state,

Figure 3 shows a hole pipe of the internal cavity filling system of the waste structure according to the present invention

Cross-section,

Figure 4 shows a double oil pipe of the cavity internal cavity filling system according to the present invention

One Section,

Figure 5 shows the pore hose of the cavity filling system inside the waste structure according to the present invention

Cross-section,

Figure 6 is a fibrous hose of the inner cavity filling system of the waste structure according to the present invention

Shown cross section.                 

Explanation of symbols on the main parts of the drawing

10: closed 12: inlet

14: partition 20: perforated pipe

20a: Double pipes 22: Inner pipe

24: appearance 26: outlet

28: attachment ring 30: injection material

40: closed mine 50: closed circuit TV

60: fiber hose 62: reinforcing bar ring

70: pore hose 72: pore

The present invention relates to a hollow structure filling system and a filling method using the same, in particular, by installing a hole or a hole, a fiber hose, etc. in the inner cavity of a closed mine, a closed pipe, a closed cave (hereinafter referred to as "closed structure"), According to the internal cavity state (size, degree of bending, etc.) of the waste structure, the hollow structure internal cavity filling system for filling the internal cavity tightly by injecting the injection material into a specific area through the oil pipe, the oil hole, the fiber hose, and the like. It relates to a filling method.

In general, the mine tunnels are temporarily operated until the mining work is completed, and thus, unlike the permanently operated civil tunnels and large underground spaces, they do not have sufficient reinforcement.

In addition, because the blasting type is exaggerated when the blasting vibration control is completely excluded, the rock and the surrounding wall of the tunnel are damaged by the blasting vibration, and the crack layer is developed, so that the tunnel relaxation area is spread. Is characteristic.

Subsidence due to abandoned mine can be divided into Trough type sink and sinkhole type sink.

Trough-type settlements generate a gradual slow surface subsidence curve over a large area, and may show an amount of settlement that is not well recognized over a long period of time, which is caused by the destruction or punching of Gwangju that supported the upper half. Although the settlement is small, it has the characteristic of occurring slowly and generally moderately in the long term over a large area and does not affect the stability of the upper structure.

On the other hand, since sinking occurs because the sinking type sinks in the form of depressions, the sinking amount is large and difficult to predict. It is also a cylindrical or conical shape that forms steep slopes, which can range from a few meters to several tens of meters, and is transferred by the bulking of rocks due to the collapse of the upper part of the mining cavity and the decrease in strength due to the inflow of groundwater. It is a form of settlement that is small in size but can cause serious damage to life and ground structures.

Mining cavity, which acts as the biggest cause of settlement, affects settlement according to its size and shape, and also affects settlement according to the state of the upper half of the drilling cavity.

The size and shape of the mining cavity depend on the mining method and the degree of mining, and the interaction between these mining and the surrounding geological conditions will have a great influence on the settlement.

Especially in Korea, the incidence rate of ground sedimentation is high because of the collapsed mining method.

On the other hand, the ground depression occurrence time due to the mining history of the abandoned mine is determined by various factors such as coal seam strength, strength of the top and bottom rocks, fracture range, groundwater presence, cavity depth, size of the trajectory, mining size, etc. Is very difficult.

Therefore, the reinforcement method for areas concerned with ground depression by jointly should select the areas where structural and life damages are expected to be greatly affected by future depression, and comprehensively examine and apply economic feasibility, constructability, common condition, and surface condition.

In order to prevent ground subsidence damage caused by the destruction of mining surroundings, the reinforcement method should be selected considering the mining status and ground conditions of the target area by referring to the suitability and applicability of the construction method.

Techniques that can be applied to prevent ground subsidence include cavity top reinforcement, deep foundation, peer construction in the cavity, grout column, grout case, hydraulic filling, filling grout, full excavation and refilling. Not only one is applied at the construction site, but several construction methods are applied in combination depending on site conditions, applicability of construction methods, constructability and efficiency.

Cavity reinforcement is a method of grouting the cavities above the ground or applying micropile to reduce settlements and excessive inequality, and to prevent erosion by collapse.

The superstructure foundation of the cavity is constructed by grouting or micropile to behave like a rigid body so that the ground acts as an integrated composite member. In addition, because the construction on the ground has the advantage that the construction is advantageous and can prevent excessive unequal settlement of the local area, but it is difficult to completely suppress the settlement and has the disadvantage of expensive construction cost.

Deep foundation reinforcement method constructs deep foundation up to the stable layer of mining lower half and directly supports individual structures. Drills large diameter balls (8 ~ 24 inch) up to the lower half of cavity and constructs the foundation of piers or piles. .

In the case of using a pier, the concrete column is constructed in a permanent steel casing from the bottom of the cavity to the surface to support the structure.In the case of a pile, the concrete filled pipe is grounded from the bottom of the cavity after drilling by connecting the borehole to the bottom of the cavity. Constructed to support the upper half.

Peer construction in the cavity is a reinforcement method that supports pillars in the cavity by installing pillars in the cavity, and is applied to prevent temporary depression. This reinforcement method has a relatively strong rock mass around the mining area to be reinforced. Applicable only when the enemy is above the ground level, but also in areas where the cavity is flooded and where drainage is possible.

For the construction of a peer, a large diameter borehole is used to access the cavity to be constructed from the surface, or a cavity is accessed through the previous shaft.

Therefore, it is possible to work while checking the condition in the cavity, but because of the work in the mine, workability is limited and safety evaluation is important.

The grout column reinforcement method is an auxiliary support system in the form of grouted pillars or aggregate peers in which aggregates are injected through boreholes, and then grout materials are injected to form columns in underground cavities. The applicability of this method depends on the local situation, but is generally economical when the depth of the underground cavity is between 9 and 50 m.

The grout case reinforcement method is not widely used to form pillars by placing concrete after installing steel pipes from the lower part of the cavity to the upper part of the cavity, but it is applied when the size of the cavity is relatively large. If the height of the cavity is large, the grout column supporting the upper half is relatively expensive because many materials are used, and the grout case method is used as an alternative. However, this reinforcement method is only to prevent temporary depression, so it cannot be a fundamental countermeasure, and attention should be paid to construction safety since large equipment will approach the work area.

Hydraulic filling is the filling of the cavity by transferring particulate material in the form of a slurry with water. Typical hydraulic filling is remotely controlled in the cavity or near the mining site where the filling takes place, and all work is performed from the surface. The effects of hydraulic refilling include the filling of underground cavities, the lateral support role to maintain the strength of Gwangju, the removal or reduction of oxidizing conditions and acidic water, the protection of the support against weathering, the prevention or reduction of settlement. Fillers include dendritic, aggregate, sand, and cement. These materials should be examined for engineering properties by laboratory tests before filling, and permeability, specific gravity, and particle size distribution should be investigated. Based on these tests, the design of the filler can be made and the basis for predicting the behavior in the field.

Filling grout is basically a method of hydraulically filling with a mixture such as cement. In the case of reinforcement, the mixing degree of filler and cement may vary depending on the filling method and the size of filler. do. Filling grout materials include a variety of chemical compounds, including organic and fly ash mixtures, and Portland cement, with the exception of the cement being composed of fine granular materials such as sand or fly ash, and depending on the site conditions, aggregates may be used.

Full excavation and recharging is a method of removing underground cavity by blasting or completely digging the upper half using artificial instruments, and then performing dense filling up to the lower part of the cavity or using the excavated material for filling in other areas. This method is similar to open-pit mining of coal and can be applied to areas where waste mines exist in the shallows.

Therefore, the present invention has been devised to solve the problems described above, by installing a hole or a hole in the top of the inner cavity of the waste structure, and injecting the injection material in a specific area through the hole or hole Filling the cavity tightly, especially when the large amount of the waste structure is injected, the filling material is injected by additionally using the fibrous or pore hose at the bottom of the cavity inside the waste structure, thereby filling most of the internal cavity. In the area where it is impossible to inject the ceiling or bend due to the material deformation or the characteristics of the area, a hollow structure internal cavity filling system and filling method using the same are provided to fill the internal cavity tightly by injecting injection material by installing oil pipes or hole holes. Its purpose is.

In addition, in the case of the existing injection material, the injection material is produced from the origin, and it is supplemented with the system for transporting and injecting the injection material, and the injection material is produced and injected directly at the site to reduce indirect costs such as transportation costs and to reduce the loading space. And another object to provide a filling method using the same.

Waste structure internal cavity filling system according to the present invention for achieving the above object, in the waste structure buried in the ground, the excavated or drilled the upper ground in which the waste structure is embedded to form an inlet, the half Forming a plurality of inlet openings in the waste structure in a predetermined width in the same manner as the inlet formation, and at the same time to install a fibrous hose or pore hose in the interior of the perforated waste structure on the top of the inner cavity of the perforated waste structure Install the perforated pipe or hole hose using the attachment ring, and block the inside of the waste structure by using partitions such as packs and bricks in a certain section of the perforated waste structure to prevent the leakage of the injection material, the perforated pipe or perforated hose, fiber It is characterized in that it is configured to inject the injection material in a predetermined region through the hose.

In addition, the filling method using the internal cavity filling system of the waste structure according to the present invention for achieving the above object in the inner tube filling method for filling the inner cavity using the injection material in the interior of the waste pipe, the upper ground in which the waste pipe is installed Digging or drilling downwards to form an inlet; Perforating a plurality of inlets to a predetermined width in a closed tube in the same manner as forming the inlet; Installing a fibrous hose or a pore hose at the same time as installing a fibrous hose or a pore hose inside the perforated closed tube and using an attachment ring at the top of the inner cavity of the perforated closed tube; Blocking the inside of the closed tube using a partition such as a pack, a brick, and the like in the perforated closed tube; Through the step of injecting the injection material in a predetermined region through the hole or the hole, the fiber hose, etc. sequentially, it is characterized in that the interior cavity of the closed pipe is tightly filled.

Hereinafter, with reference to the accompanying drawings, the present invention will be described in detail.

1 is an exemplary view showing a state in which the hollow structure of the internal cavity filling system according to the present invention is applied to the closed pipe, Figure 3 is a cross-sectional view showing the hollow tube of the internal cavity filling system of the waste structure according to the present invention.

As shown in these figures, in the cavity structure filling system according to the present invention, in the closed pipe (10) buried in the ground, the excavated or perforated vertically down the upper ground where the closed pipe (10) is embedded half Form an inlet 12 (if there is a manhole can be used to use the existing manhole without forming a separate inlet), the inlet 12 or the closed pipe 10 located directly below the manhole Forming a plurality of inlet (12) perforation to a predetermined width, and blocks the inside of the closed pipe 10 by using a partition 14 such as a pack, brick, etc. in a predetermined section in the perforated closed pipe (10), the perforation The perforated pipe (20, 20a) or the hole hose 70 is installed as an attachment ring 28 on the inner cavity top of the closed pipe (10), through the hole pipe (20, 20a) or hole hose 70 through the closed pipe (10) Inject the injection material 30 into a predetermined area blocked by the partition 14, such as a pack, brick, etc. Rock consists.

Here, the perforated pipe (20, 20a) is divided into the perforated pipe 20 and the double pipe 20a, is installed on the inner top of the closed pipe 10, the perforated pipe 20 is made of PVC pipe, a plurality of through The formed outlet 26 is formed, the double-pore tube 20a is an inner tube 22 made of a rubber hose; An exterior 24 made of PVC and closely installed at the outer side of the inner tube 22; The exterior 24 is composed of a plurality of outlets 26 formed through.

That is, the perforated pipe 20 is made of a PVC pipe, it consists of a plurality of outlets 26 formed through, the double perforated pipe 20a is an outer tube 24 made of PVC pipe and the inner pipe 22 made of a rubber hose ), And an outlet 26 penetrating through the exterior 24.

It will be described with respect to the filling using the internal structure filling system of the waste structure according to the present invention having the configuration as described above.

Filling method using the internal cavity filling system of the waste structure according to the present invention in the filling pipe 10 inside the filling method for filling the inner cavity using the injection material 30 to the inside of the waste pipe 10, the closed pipe 10 is Digging or drilling downward in the installed upper ground to form the inlet 12; Drilling a plurality of inlets 12 in a predetermined width in the closed pipe 10 in the same manner as forming the inlet 12; At the same time as installing the fibrous hose 60 or the hole hose 70 in the inner of the perforated closed pipe 10, using the attachment ring 28 on the top of the inner cavity of the perforated closed pipe 10, the perforated pipe 20, 20a) or installing the hole hose 70; Blocking the inside of the closed pipe (10) using a partition (14) such as a pack, a brick, and the like in the perforated closed pipe (10); Injecting the injection material 30 in a predetermined region through the fibrous hose 60, the hole tube 20, 20a or the hole hose 70 in sequence, filling the interior cavity of the closed tube 10 tightly It is characterized by.

Here, the step of injecting the injection material 30 into the closed pipe 10 through the hole pipe (20, 20a) in the case of the hole pipe end pipe through the PVC pipe outlet 26 to the inside of the closed pipe 10 In the case of the double perforated pipe 20a, the injection material 30 is injected into the inner tube 22 and the inner material 22 is drawn back, while the injection material 30 is closed to the outlet 26 of the exterior 24. 10 is injected into the interior.

After the filling of the injection material 30 is completed as described above, in the case of the perforated pipe end pipe 20 to refill the water by injecting water or blowing air, in the case of the double perforated pipe (20a) the inner tube (22) first Place it in its original position to refill it with water or blow air.

That is, the filling method using the hollow structure internal cavity filling system according to the present invention is installed on the upper end of the inner cavity of the closed pipe (10), the perforated pipe (20, 20a) is installed, the injection material in a specific area through the perforated pipe (20, 20a) It is the technical idea of the present invention to fill the internal cavity tightly by injecting 30).

Here, by installing the pores 20, 20a to administer the injection material 30 can be remotely injected, it can be filled tightly to the area impossible to inject, such as the bent portion or the ceiling of the cavity, through which the joint filling is complete or not You can check.

   EXAMPLE

Hereinafter, the present invention will be described in more detail with reference to Examples.

Figure 2 is an exemplary view showing a state in which the hollow structure of the internal cavity filling system according to the present invention is applied to the abandoned mine, Figure 4 is a cross-sectional view showing a double hollow pipe of the internal cavity filling system of the waste structure according to the present invention, Figure 5 Fig. 6 is a cross-sectional view showing the oil hole of the hollow structure internal filling system according to the present invention, Figure 6 is a cross-sectional view showing the fibrous hose of the hollow structure internal filling system according to the present invention.

 As shown in these figures, in the cavity structure filling system according to the present invention, in the conventional old abandoned mine 40, the closed circuit TV 50 is installed at a predetermined position in the abandoned mine 40, and A fibrous hose 60 or a porous hose 70 is installed at the bottom of the inner cavity of the abandoned mine 40, and the injection material 30 is injected into the fibrous hose 60 or the porous hose 70, and the abandoned mine 40 is disposed. Charge my internal cavity.

In this case, the fibrous hose 60 is provided with a hose made of fiber and a socket-type reinforcing bar ring 62 installed in close contact with one end of the hose.

That is, the fibrous hose 60 can be assembled using the reinforcing ring 62 according to the cavity length by the socket connection type, and also the volume is small, easy to move, particularly high-pressure injection can be filled in bulk Do.

In addition, the air hole hose 70 is injected into the injection material 30 through the hole 72, but does not enter the inside of the hole hose 70, and re-injecting the hole after leaving the hole 70 is completed This is possible.

It describes a charging method using the internal cavity filling system of the waste structure according to the present invention having the configuration as described above.

The charging method using the internal cavity filling system of the waste structure according to the present invention comprises the steps of installing a closed circuit TV (50) at a predetermined position in the abandoned mine (40) in the common cavity filling method of the old abandoned mine (40); Installing a fiber hose (60) or a hole hole (70) on the inner cavity bottom of the abandoned mine (40) and a hole hole (70) on the ceiling cavity inside the abandoned mine (40); Injecting the injection material 30 into the fibrous hose 60 and the hole hose 70; After the injection is completed using the compressor into the injection tube into the air or while passing through the sponge to manage the re-injection after cleaning; by sequentially performing, the internal cavity in the abandoned mine 40 is filled with the injection material 30. .

Here, the step of injecting the injection material 30 in the fibrous hose 60 and the hole hose 70 is characterized in that the injection of the injection material 30 at a high pressure while drawing the fiber hose 60 in the membrane direction do.

In addition, a step of filling the injection material 30 in the ceiling portion or a predetermined portion in the abandoned mine 40 by using the pore hose 70 is added.

That is, the filling method using the internal cavity filling system of the waste structure according to the present invention is a closed circuit TV (50) when installing the fibrous hose (60) or pore hose (70) in the bent or remote area in the case of the closed light (40) ) Is installed in parallel, and filling the inner cavity tightly while confirming the injection state of the injection material 30 is a technical idea of the present invention.

In particular, the pore hose 70 is installed on the ceiling or side surface of the abandoned mine 40, and the injection material 30 is administered through the pore 72 of the pore hose 70. It can be charged tightly to the area that cannot be injected, such as above or the ceiling, and can check safety and perfect construction while checking the completion of the joint charging through the closed circuit TV (50).

On the other hand, as described above, the injection material 30 used in the internal cavity filling system and the filling method using the same according to the present invention is prepared by mixing an appropriate amount of cement and WGS700 (product name developed by the applicant of the present invention), and compression The strength is 5 ~ 80kgf / ㎠ and can be arbitrarily adjusted, automatic leveling is possible, no material separation phenomenon, and excellent flowability.

Therefore, the cement and WGS700 is mixed in the field to manufacture the injection material 30 can be directly injected, if there is water in the cavity during injection, the injection material 30 to fill the cavity while absorbing water.

In addition, the injection material 30 is filled with a lightweight foamed concrete mixed with a mixture of cement and water in a lightweight styropole concrete or a mixture of animal and vegetable foam material in a paste using cement and water.

The injector used for filling the injection material 30 uses a mobile or stationary pump car, and the injection pressure is 80 kgf / cm 2 at maximum, and it is revealed that a large amount of injection and a long distance (up to 1 km) are possible.

As described above, the internal cavity filling system and the filling method using the same according to the present invention has the following effects.

First, the hollow structure filling system and the filling method using the same according to the present invention is installed in the hole structure hole hole or hole hose, and the injection of the light-foaming material through the hole hole or hole hose can be injected remotely In addition, there is an advantage that can be filled tightly to the area impossible to inject, such as the bent portion or the ceiling of the cavity.

Second, the internal cavity filling system and the filling method using the same according to the present invention can be re-injected through a pre-installed perforated pipe or pore hose when re-injection is necessary due to the behavior of the ground or deformation of the injection material after a certain period of time. Therefore, there is an advantage that can be maintained in the long term.

Third, the internal cavity filling system and the filling method using the same according to the present invention are various, such as selection of perforated pipes or perforated hoses, injection materials (fluidity, strength) according to the characteristics of the cavity (closed mine, abandoned cave, closed tunnel, closed pipe, etc.) and the situation. There is an advantage that the injection method can be applied.

Fourth, the internal cavity filling system and the filling method using the same according to the present invention produces an injection material in the field, and directly injected into the waste structure has the advantage of reducing the transportation cost of raw materials and shorten the air during large-scale construction.

Fifth, the internal cavity filling system and the filling method using the same according to the present invention has no damage caused by noise or vibration in the city, there is no cause of civil complaints, and there is an advantage that the construction can be performed even in places where equipment is small and narrow. .

Sixth, the internal cavity filling system and the filling method using the same according to the present invention has the advantage that can be confirmed whether the filling of the filling material through the hole pipe installed in the waste structure.

Seventh, the internal cavity filling system and the filling method using the same according to the present invention is a safe and perfect while confirming the injection state of the injection material by installing a closed circuit TV in parallel when installing the perforated pipe in the bent or remote area in the case of abandoned mines Construction can be done.

Claims (17)

delete delete Excavation or perforation of the upper part of the ground in which the closed pipe and the abandoned mine are buried vertically to form an inlet, and a plurality of closed pipes and the closed mine which are located directly below the inlet to be formed to a predetermined width, and the perforated A perforated pipe or a closed hole is installed at the top of the inner cavity of the closed pipe and the abandoned mine, and a certain section of the perforated closed pipe and closed mine is blocked by using a partition to block the closed pipe and the closed mine, and the closed pipe and the closed mine partition through the pipe. In the joint structure filling system of the waste structure injecting the injection material in a certain area blocked by The hole pipe is an inner tube made of a rubber hose; An exterior made of PVC and installed at the outside of the inner tube; The internal structure filling system of the waste structure, characterized in that consisting of a double perforated pipe consisting of a plurality of outlets formed through the exterior. delete delete delete Digging or digging downward in the upper ground where the closed pipe and the abandoned mine are installed to form an inlet; Perforating a plurality of inlets to a predetermined width in a closed tube / closed mine by the same method as forming the inlet; Installing a fiber hose or a pore hose inside the perforated closed tube and the abandoned mine, and at the same time installing a perforated tube or perforated hose using an attachment ring on the upper end of the inner cavity of the perforated closed tube and the abandoned mine; Blocking a closed portion of the closed tube and the closed mine using a partition in the perforated closed tube and the closed mine; In the filling method using the internal structure filling system of the waste structure to perform the step of injecting the injection material in a predetermined area through the fibrous hose, the hole pipe or the hole hole in order to fill the inner cavity of the closed pipe, closed mine tightly, After the completion of the injection of the hollow pipe, the double hollow pipe is a filling method using a cavity internal filling system, characterized in that the injection of the inner pipe to the original position by injecting air into the inner pipe using a compressor to clean and re-inject. Digging or digging downward in the upper ground where the closed pipe and the abandoned mine are installed to form an inlet; Perforating a plurality of inlets to a predetermined width in a closed tube / closed mine by the same method as forming the inlet; Installing a fiber hose or a pore hose inside the perforated closed tube and the abandoned mine, and at the same time installing a perforated tube or perforated hose using an attachment ring on the upper end of the inner cavity of the perforated closed tube and the abandoned mine; Blocking a closed portion of the closed tube and the closed mine using a partition in the perforated closed tube and the closed mine; In the filling method using the internal structure filling system of the waste structure to perform the step of injecting the injection material in a predetermined area through the fibrous hose, the hole pipe or the hole hole in order to fill the inner cavity of the closed pipe, closed mine tightly, After completion of the injection of the hollow tube, the double hollow tube is refilled after cleaning the injection pipe while passing the sponge into the inner tube to the inner tube inside, the filling method using a cavity filling system inside the waste structure. delete delete delete delete delete Providing a closed circuit TV at a predetermined position in a closed mine or a closed mine; Installing a fiber hose or a pore hose at an inner cavity bottom of the abandoned mine and a hollow hole, and at the same time installing a hollow hole at a cavity ceiling of the abandoned mine or abandoned mine; In the filling method using the joint structure filling system of the waste structure to fill the cavity of the abandoned mine, closed cave tightly by sequentially injecting the injection material into the fibrous hose and oil hole hose, After the completion of the injection of the hollow pipes, the double hollow pipes are filled by using the internal cavity filling system of the waste structure, characterized in that the injection and cleaning after re-injecting the air inside the inner pipe by using a compressor. Providing a closed circuit TV at a predetermined position in a closed mine or a closed mine; Installing a fiber hose or a pore hose at an inner cavity bottom of the abandoned mine and a hollow hole, and at the same time installing a hollow hole at a cavity ceiling of the abandoned mine or abandoned mine; In the filling method using the joint structure filling system of the waste structure to fill the cavity of the abandoned mine, closed cave tightly by sequentially injecting the injection material into the fibrous hose and oil hole hose, After the completion of the injection of the hollow tube is a double hollow tube is filled with the internal cavity filling system, characterized in that the re-injected after cleaning while passing the sponge inside the inner tube to the injection inner tube. delete delete

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