A method for treating high-heaving zone cavities using a gunite process

Abstract

The application provides a method for treating a high-falling area cavity by using a gunite process, and the method comprises the following steps: knocking the roof and wall of the high-falling area, removing the live gangue and live stone, cleaning the surface to be sprayed, and reinforcing the roof of the high-falling area; preparing a polyether polyol solution and a polymeric MDI solution; introducing the polyether polyol solution and the polymeric MDI solution into a high-pressure spray gun, and spraying and filling the high-falling area by a plurality of times by using the high-pressure spray gun; and observing the roof and monitoring the gas of the high-falling area after the spraying is completed. The polyether polyol solution and the polymeric MDI solution are mixed to form a polyurethane material in the high-pressure spray gun, the polyurethane material is expanded and solidified after being sprayed, a complete jointless elastomer coating is formed, cracks can be effectively blocked, and the overflow of harmful gas can be prevented, so that the gas accumulated in the high-falling area is fundamentally treated, and the safety of the mine is improved. Moreover, the material consumption is greatly reduced, the frequency of material transportation is reduced, and the workload of construction is reduced.

Description

Technical Field

[0001] This invention relates to the field of coal mine engineering technology, and in particular to a method for treating cavities in high-risk areas using shotcrete technology. Background Technology

[0002] When tunneling underground in coal mines, some areas may experience roof instability, making it impossible to maintain the tunnel's cross-sectional shape. These areas may then collapse naturally or be artificially supported, creating sections with a cross-sectional shape larger than the designed shape – these are known as high-risk areas. To prevent further roof collapse in these high-risk areas, it is necessary to reinforce the roof with methods such as installing additional anchor cables, hanging wire mesh, and erecting timber supports.

[0003] After the roof of the high-risk area is reinforced, its roof structure becomes stable. However, the space formed by the collapse of the roof coal and rock is not filled. There is gas in the airflow in the roadway, and the coal and rock mass will also release gas naturally. Since gas is lighter than air, gas will accumulate in the space formed, causing local gas exceedance. Commonly used methods for dealing with gas accumulation in high-risk areas underground include: filling the cavity, airflow dispersion and drainage. Among them: (1) Filling the cavity means that for high-risk areas not exceeding 800mm, coal is filled in woven bags. For high-risk areas exceeding 800mm, cement mortar or foam inhibitor is injected into the cavity using a grouting pump to fill the cavity. (2) The airflow dispersion method refers to the following: when the wind speed in the roadway is greater than 0.5 m / s, the airflow guide method is adopted, and the lower end of the airflow guide is tilted towards the windward direction of the roadway; the upper end is raised to an appropriate position in the collapse space and tilted towards the windward direction of the roadway. The material of the airflow guide can be wooden boards, canvas or ventilation duct cloth, etc. (3) The extraction method refers to the following: if the gas emission in the high collapse area is very large and the air volume in the roadway is insufficient, if the gas discharged by the airflow dispersion method causes the gas in the roadway to exceed the limit, one or more branch pipes are connected from the extraction pipe and extended to the collapse roof to extract the accumulated gas.

[0004] While airflow dispersion and extraction methods dilute and remove gas from high-risk areas, they do not address the roof space within these areas. The cavity filling method, on the other hand, eliminates the space for gas accumulation, fundamentally removing the conditions for gas buildup. However, existing cavity filling methods require continuous spraying of cement mortar or foam inhibitors using grouting pumps, resulting in large material consumption, multiple grout transports, and a high workload. Summary of the Invention

[0005] The present invention aims to at least partially solve one of the technical problems in the related art. To this end, the embodiments of the present invention provide a method for treating cavities in high-rise areas using shotcrete technology, which can reduce the amount of material used and reduce the amount of construction work.

[0006] This application proposes a method for treating cavities in high-rise areas using shotcrete technology, comprising the following steps:

[0007] S1, knock on the sides and roof of the high-risk area, remove loose gangue and loose rocks, wash the surface to be sprayed clean, and reinforce the roof of the high-risk area;

[0008] S2, prepare polyether polyol solution and polymerized MDI solution, and store them in the first material tank and the second material tank respectively;

[0009] S3, the polyether polyol solution and polymeric MDI solution are introduced into the high-pressure spray gun, and the construction workers use the high-pressure spray gun to spray and fill the high-protrusion area multiple times.

[0010] S4. After the shotcrete is completed, roof observation and gas monitoring are carried out in the high-risk area, and the site is cleaned up.

[0011] This application uses polyether polyol solution and polymeric MDI solution to mix in a high-pressure spray gun to form a polyurethane material. After spraying, it expands and cures to form a complete seamless elastomer coating, which can effectively seal cracks, prevent the leakage of harmful gases, fundamentally control the gas accumulation in high-risk areas, and improve the safety of the mine.

[0012] The polyurethane material sprayed in this application can expand to 25-30 times its original volume, thus significantly reducing the amount of material used, the frequency of material transportation, and the workload of construction.

[0013] In some embodiments, in step S3, the volume ratio of the polyether polyol solution and the polymeric MDI solution mixed in the high-pressure spray gun is 1:(0.95~1.05). Using this ratio for mixing can improve the adhesion of the polyurethane material, allowing it to adhere to the rock surface immediately after spraying.

[0014] It should be noted that when the polyether polyol solution is in excess, the reaction rate of the slurry will accelerate, the nozzle of the spray gun will be easily blocked, and the strength of the resulting polyurethane material will also be reduced. When the polymeric MDI solution is in excess, it will cause problems such as increased material reaction temperature, making it impossible to achieve the desired air-sealing effect during spraying. Therefore, the volume ratio of polyether polyol solution and polymeric MDI solution when mixed is limited to 1:(0.95~1.05).

[0015] Preferably, the volume ratio of the polyether polyol solution and the polymeric MDI solution is 1:1.

[0016] In some embodiments, the method of multiple grouting in step S3 is as follows: first, grout is sprayed onto the top of the high-rise area for the first time. After the sprayed grout has fully expanded and solidified, grout is sprayed again below the solidified grout for the nth time, where n is greater than 1, until the lower end of the grout is basically flush with the lower end of other top plates around the high-rise area.

[0017] In some embodiments, in step S3, when the high-risk area is a conical space, the conical space is divided into m layers of shotcrete zones according to the height of the conical space, where m is greater than or equal to 1; when m is greater than 1, a top-to-bottom layered shotcrete method is adopted.

[0018] In some embodiments, the layered spraying method in step S3 is as follows:

[0019] The first shotcrete layer is formed at the top of the high-risk area.

[0020] Below the first sprayed grouting area is the second sprayed grouting area. After the grout in the first sprayed grouting area has fully expanded and completely solidified, a second spraying is carried out on any side of the second sprayed grouting area, and then a third spraying is carried out on the other side until the lower end of the second sprayed grouting is basically flush with the lower end of the third sprayed grouting.

[0021] Below the second shotcrete zone is the third shotcrete zone, and so on, until the lower end of the lowest shotcrete layer in the conical space is basically flush with the lower end of the other roof slabs around the high-rise area.

[0022] In some embodiments, when spraying the third layer of grout, the grout is first sprayed below the second spraying point, and then sprayed below the third spraying point. This shortens the waiting time for the upper layer of grout to fully expand and completely cure, and so on. This prevents the grout from clogging the nozzle of the spray gun during construction intervals and ensures that the upper layer of grout expands fully, reducing grout loss.

[0023] It should be noted that when spraying the second layer of shotcrete, if the left side is sprayed first, then when spraying the third layer, the left side should also be sprayed first. This is because if the left side of the second layer is sprayed first, the grout on the left side will begin to expand and solidify while the right side is being sprayed. When the third layer is sprayed, the grout on the left side of the second layer will only need a relatively short time to fully expand and solidify before being sprayed underneath, thus shortening the waiting time.

[0024] In some embodiments, when a canopy is erected in the high-risk area, shotcrete is applied to both sides of the high-risk area after the first shotcrete application.

[0025] In some embodiments, in step S3, before the shotcrete construction, the equipment and facilities near the high-risk area are isolated and protected to prevent the shotcrete from adhering to the equipment and facilities.

[0026] It should be noted that during shotcreting, the polyurethane material is ejected from the nozzle of the high-pressure spray gun and disperses in a cone shape, adhering to the objects it comes into contact with. The material has extremely high viscosity, and once the slurry expands and hardens, it is difficult to remove from the adhered material. The sides of the underground roadway are lined with compressed air, water supply, and other pipelines, some of which contain gas drainage pipes and water drains. If these facilities are not isolated and protected, it will affect the site's environmental hygiene, and the hardened material adhering to the pipelines will detract from the roadway's aesthetics. Therefore, before shotcreting, it is necessary to isolate and protect the equipment and facilities near the construction site. Once the shotcrete material has hardened, the isolation and protection measures can be removed, restoring the roadway to its original appearance.

[0027] Specifically, isolation and protection measures can be implemented according to the site conditions. For example, woven bags can be used to wrap the pipelines, and canvas can be used to cover the equipment, etc.

[0028] In some embodiments, the time for the slurry to fully expand and completely cure is 4-5 minutes.

[0029] In some embodiments, in step S4, after cleaning the site, a sign is hung at the shotcrete filling area. Attached Figure Description

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings.

[0031] in:

[0032] Figure 1 This is a diagram illustrating the shotcrete construction sequence in the high-risk area according to an embodiment of this application. Detailed Implementation

[0033] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0034] The following describes a method for treating cavities in high-rise areas using a shotcrete process, according to an embodiment of the present invention, with reference to the accompanying drawings.

[0035] This application proposes a method for treating cavities in high-rise areas using shotcrete technology, comprising the following steps:

[0036] S1. In the high-risk area, knock on the sides and roof to remove loose rock and debris, wash the surface to be sprayed with high-pressure water, reinforce the roof of the high-risk area, and isolate and protect the equipment and facilities near the high-risk area to prevent the sprayed grout from adhering to the equipment and facilities.

[0037] It should be noted that during shotcreting, the polyurethane material is ejected from the nozzle of the high-pressure spray gun and disperses in a cone shape, adhering to the objects it comes into contact with. The material has extremely high viscosity, and once the slurry expands and hardens, it is difficult to remove from the adhered material. The sides of the underground roadway are lined with compressed air, water supply, and other pipelines, some of which contain gas drainage pipes and water drains. If these facilities are not isolated and protected, it will affect the site's environmental hygiene, and the hardened material adhering to the pipelines will detract from the roadway's aesthetics. Therefore, before shotcreting, it is necessary to isolate and protect the equipment and facilities near the construction site. Once the shotcrete material has hardened, the isolation and protection measures can be removed, restoring the roadway to its original appearance.

[0038] Specifically, isolation and protection measures can be implemented according to the site conditions. For example, woven bags can be used to wrap the pipelines, and canvas can be used to cover the equipment, etc.

[0039] S2, prepare polyether polyol solution and polymerized MDI solution, and store them in the first material tank and the second material tank respectively.

[0040] S3 involves introducing the polyether polyol solution and polymerized MDI solution into the high-pressure spray gun. A grout pump is used in conjunction with the high-pressure spray gun to pump the materials from the first and second material buckets into the high-pressure spray gun. Construction workers then use the high-pressure spray gun to repeatedly fill the high-protrusion areas with grout.

[0041] S4. After shotcreting is completed, roof observation and gas monitoring are conducted in the high-risk area. The site is cleaned up, and a sign is hung at the shotcrete filling area. Specifically, it is observed whether the lower surface of the shotcrete filling material is flush with the lower surface of the surrounding roof, and the gas concentration in the high-risk area is monitored to see if it exceeds the standard.

[0042] This application embodiment uses a polyether polyol solution and a polymeric MDI solution, which are mixed in a high-pressure spray gun to form a polyurethane material. This material is then sprayed through an atomizing nozzle. After spraying, the material adheres to the exposed coal and rock mass, anchor mesh, and anchor bolts (cables) at the top of the roof fall area, and expands and cures. During spraying, the material is applied layer by layer and in sections from top to bottom. After expansion, the polyurethane material fills the space in the roof fall area, forming a complete, seamless elastomer coating. This effectively seals cracks, prevents the leakage of harmful gases, fundamentally controls the accumulation of gas in high-fall areas, reduces airflow loss, and improves mine safety.

[0043] The polyurethane material sprayed in this embodiment has strong adhesion and can bond with various materials such as coal and concrete. After complete curing, the polyurethane material has excellent sealing properties, providing waterproofing, leak sealing, airtightness, insulation, and heat insulation. It also effectively prevents damage from the deliquescence and weathering of surrounding rock and corrosion of metal components. The polyurethane material can expand to 25-30 times its original volume, thus significantly reducing material usage, the frequency of material transportation, and the workload of construction.

[0044] The method described in this application is simple and quick to construct, convenient to transport materials, saves labor costs, uses simple construction tools, is not affected by the height of the roof fall, and can completely seal the roof fall area in one construction.

[0045] In some specific embodiments, the roof of the high-risk area is reinforced by adding anchor bolts and steel strips.

[0046] In some specific embodiments, in step S3, the volume ratio of the polyether polyol solution and the polymeric MDI solution mixed in the high-pressure spray gun is 1:(0.95~1.05). Using this ratio for mixing can improve the adhesion of the polyurethane material, allowing it to adhere to the rock surface immediately after spraying.

[0047] It should be noted that when the polyether polyol solution is in excess, the reaction rate of the slurry will accelerate, the nozzle of the spray gun will be easily blocked, and the strength of the resulting polyurethane material will also be reduced. When the polymeric MDI solution is in excess, it will cause problems such as increased material reaction temperature, making it impossible to achieve the desired air-sealing effect during spraying. Therefore, the volume ratio of polyether polyol solution and polymeric MDI solution when mixed is limited to 1:(0.95~1.05).

[0048] The polyurethane material produced by mixing polyether polyol solution and polymeric MDI solution meets the technical specifications in terms of dimensional stability, compressive strength, and flame retardancy, as detailed in Table 1.

[0049] Table 1

[0050]

[0051] Preferably, the volume ratio of the polyether polyol solution and the polymeric MDI solution is 1:1.

[0052] In some specific embodiments, in step S3, the method of multiple grouting is as follows: first, the top of the high-rise area is sprayed with grout for the first time. After the sprayed grout has fully expanded and solidified, the nth grouting is continued below the solidified grout, where n is greater than 1, until the lower end of the grout is basically flush with the lower end of other top plates around the high-rise area, and the grouting surface is smoothed.

[0053] In some specific embodiments, in step S3, when the high-risk area is a conical space, the conical space is divided into m layers of sprayed grouting zones according to the height of the conical space, where m is greater than or equal to 1; when m is greater than 1, a top-down layered spraying method is adopted.

[0054] In some specific embodiments, the layered spraying method in step S3 is as follows:

[0055] The first shotcrete layer is formed at the top of the high-risk area.

[0056] Below the first sprayed grouting area is the second sprayed grouting area. After the grout in the first sprayed grouting area has fully expanded and completely solidified, a second spraying is carried out on any side of the second sprayed grouting area, and then a third spraying is carried out on the other side until the lower end of the second sprayed grouting is basically flush with the lower end of the third sprayed grouting.

[0057] Below the second shotcrete zone is the third shotcrete zone, and so on, until the lower end of the lowest shotcrete layer in the conical space is basically flush with the lower end of the other roof slabs around the high-rise area.

[0058] When spraying the third layer of grout, first spray below the second spraying point, then spray below the third spraying point. This shortens the waiting time for the upper layer of grout to fully expand and cure, and so on. This prevents grout from clogging the spray gun nozzle during construction intervals and ensures that the upper layer of grout expands fully, reducing grout loss.

[0059] It should be noted that when spraying the second layer of shotcrete, if the left side is sprayed first, then when spraying the third layer, the left side should also be sprayed first. This is because if the left side of the second layer is sprayed first, the grout in the left side will have already begun to expand and solidify while the right side is being sprayed. Therefore, when the third layer is sprayed, the grout in the left side of the second layer will only need a relatively short time to fully expand and solidify before being sprayed underneath, thus shortening the waiting time. Specifically, as follows... Figure 1 As shown, the spraying is performed in the order of abcdefg.

[0060] In some specific embodiments, when the high-risk area is covered, after the first shotcrete is applied, that is, after the top and sides of the roadway are shotcreted, the two sides of the high-risk area are reinforced with shotcrete to prevent the coal body on the two sides of the area from becoming unstable, and to reduce the wind resistance generated by the covering.

[0061] In some specific embodiments, the time for the slurry to fully expand and completely solidify is 4-5 minutes.

[0062] The present application will be further illustrated by specific embodiments below.

[0063] Example 1

[0064] A method for treating cavities in high-rise areas using shotcrete technology includes the following steps:

[0065] S1. In the high-risk area, knock on the sides and roof to remove loose rocks and boulders, wash the surface to be sprayed with high-pressure water, reinforce the roof of the high-risk area by installing additional anchor bolts and steel strips, and isolate and protect the equipment and facilities near the high-risk area to prevent the sprayed grout from adhering to the equipment and facilities.

[0066] S2, prepare polyether polyol solution and polymeric MDI solution at a volume ratio of 1:1, and store them in the first and second material containers respectively. Before construction, they are lowered from the ground storage point to the well and then transported to the vicinity of the construction area.

[0067] S3. The polyether polyol solution and polymeric MDI solution are introduced into the high-pressure spray gun. A grouting pump is used in conjunction with the high-pressure spray gun to pump the materials from the first and second material tanks into the high-pressure spray gun. During use, the polyether polyol solution and polymeric MDI solution are used at a volume ratio of 1:1. Construction workers use the high-pressure spray gun to fill the high-protrusion areas with grout.

[0068] The shotcrete filling method is as follows: the high-risk area is divided into a first shotcrete zone, a second shotcrete zone and a third shotcrete zone from top to bottom, and shotcrete is applied in layers from top to bottom.

[0069] Specifically:

[0070] Q1. Perform the first shotcrete at the top of the high-risk area to form the first shotcrete zone;

[0071] Q2. Below the first sprayed area is the second sprayed area. After the slurry in the first sprayed area has fully expanded and completely cured, the second spraying is carried out on the left side of the second sprayed area, and then the third spraying is carried out on the right side until the lower end of the second sprayed slurry is basically flush with the lower end of the third sprayed slurry.

[0072] Q3. Below the second sprayed grout zone is the third sprayed grout zone. When spraying the third sprayed grout zone, first perform the fourth and fifth sprays below the second sprayed grout zone, and then perform the sixth and seventh sprays below the third sprayed grout zone to shorten the waiting time for the upper layer of grout to fully expand and completely cure. Figure 1 As shown, spray grout in the order of abcdefg. Continue spraying until the lower surface of the grout is basically flush with the lower surface of the surrounding roof slab, and then smooth the sprayed surface. This prevents the grout from clogging the nozzle of the spray gun during construction intervals and ensures that the previous layer of grout expands sufficiently, reducing grout loss.

[0073] S4. After shotcreting is completed, roof observation and gas monitoring are conducted in the high-risk area. The site is cleaned up, and a sign is hung at the shotcrete filling area. Specifically, it is observed whether the lower surface of the shotcrete filling material is flush with the lower surface of the surrounding roof, and the gas concentration in the high-risk area is monitored to see if it exceeds the standard.

[0074] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0075] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0076] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0077] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0078] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0079] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for treating cavities in high-rise areas using shotcrete technology, characterized in that, Includes the following steps: S1, knock on the sides and roof of the high-risk area, remove loose gangue and loose rocks, wash the surface to be sprayed clean, and reinforce the roof of the high-risk area; S2, prepare polyether polyol solution and polymerized MDI solution, and store them in the first material tank and the second material tank respectively; S3. A polyether polyol solution and a polymeric MDI solution are introduced into a high-pressure spray gun. The polyether polyol solution and polymeric MDI solution mix within the high-pressure spray gun to form a polyurethane material, which is then sprayed out through an atomizing nozzle. Construction workers use the high-pressure spray gun to repeatedly fill the high-risk area with grout. After spraying, the material adheres to the exposed parts of the coal and rock mass, anchor mesh, anchor bolts, or anchor cables at the top of the fall area, and expands and cures. The expanded polyurethane material fills the space at the fall top, forming a complete, seamless elastomer coating that effectively seals cracks. When the high-risk area is a conical space, the conical space is divided into m layers of grouting zones according to its height, where m is greater than or equal to 1. When m is greater than 1, a top-down layered grouting method is used. The first shotcrete layer is formed at the top of the high-risk area. Below the first sprayed grouting area is the second sprayed grouting area. After the grout in the first sprayed grouting area has fully expanded and completely solidified, a second spraying is carried out on any side of the second sprayed grouting area, and then a third spraying is carried out on the other side until the lower end of the second sprayed grouting is basically flush with the lower end of the third sprayed grouting. Below the second shotcrete zone is the third shotcrete zone, and so on, until the lower end of the lowest shotcrete in the conical space is basically flush with the lower end of the other top plates around the high-rise area. When spraying the third layer of grout, first spray grout below the second grouting area, and then spray grout below the third grouting area to shorten the waiting time for the upper layer of grout to fully expand and completely cure, and so on. S4. After the shotcrete is completed, roof observation and gas monitoring are carried out in the high-risk area, and the site is cleaned up.

2. The method for treating cavities in high-rise areas using shotcrete technology according to claim 1, characterized in that, In step S3, the volume ratio of the polyether polyol solution and the polymeric MDI solution mixed in the high-pressure spray gun is 1:(0.95~1.05).

3. The method for treating cavities in high-rise areas using shotcrete technology according to claim 1, characterized in that, When erecting sheds in high-risk areas, spray grout onto both sides of the high-risk areas after the first shotcrete application.

4. The method for treating cavities in high-rise areas using shotcrete technology according to any one of claims 1-3, characterized in that, In step S3, before the shotcrete construction, the equipment and facilities near the high-risk area are isolated and protected.

5. The method for treating cavities in high-rise areas using shotcrete technology according to claim 1, characterized in that, The slurry takes 4-5 minutes to fully expand and solidify.

6. The method for treating cavities in high-rise areas using shotcrete technology according to claim 1, characterized in that, In step S4, after cleaning the site, a sign is hung at the shotcrete filling area.

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