Method for reinforcing hard rock mined chamber by support method and support structure of hard rock mined chamber

Abstract

The present invention discloses a method for reinforcing a hard rock mined-out chamber by a support method and a hard rock mined-out chamber support structure, the method comprising: surveying and measuring the chamber to determine the positions of multiple supporting piers on the chamber bedrock surface; setting bottom anchor rods at the positions of the supporting piers on the chamber bedrock surface, and pouring concrete to the designed elevation to form supporting piers; trimming the chamber top rock surface corresponding to the supporting piers so that the top rock surface is low at the position of the supporting piers and high around the position of the supporting piers; pouring concrete on the tops of multiple supporting piers to form a top beam, the top beam is partially embedded in the chamber top rock surface and matches the shape of the top rock surface. The method of the present invention solves the problem of reinforcing underground chambers with large spans, has simple construction and operation, high reliability, can ensure the safety and stability of the mined-out chamber, has significant economic benefits, and has promotion value.

Description

Technical Field

[0001] The present invention relates to the technical field of chamber reinforcement, in particular to a method for reinforcing a hard rock mined chamber by a support method and a hard rock mined chamber support structure. Background Art

[0002] As cities expand, more and more areas above goafs are being used for construction. "Goaf chambers" refer specifically to artificial cavities formed by underground mining. Generally, the surrounding rock strength is high and has certain self-stabilizing characteristics in the short term. However, with the accumulation of time, changes in the properties of the surrounding rock, or changes in stress conditions, goaf chambers may also become unstable and damaged, causing changes in the spatial displacement of the overlying rock and soil, and losing their original self-stabilizing state. Especially when a construction site is built on the goaf chamber, if the goaf chamber below is not reinforced, once the goaf collapses, it will cause extremely serious consequences.

[0003] However, most underground chambers are inaccessible to large construction equipment, and with the accumulation of time, most chambers contain thick silt. Therefore, due to the influence of the construction environment and other factors, there are few cases of using the support method to manage goaf chambers. The principle of the support method is to reinforce the area with large span of the goaf and the goaf in a basically stable state with columns and piers, reduce the span of the goaf, bear additional stress, prevent the development and spread of tension cracks in the cave roof, and achieve safety and stability. The support method has greater economic advantages than the full-filling treatment method in terms of material use, and can achieve the purpose of saving both resources and engineering costs.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a method for reinforcing hard rock mined chambers by a support method, which solves the problem of reinforcing underground chambers with large spans, has simple construction operations, high reliability, can ensure the safety and stability of the mined chambers, has significant economic benefits, and has promotion value.

[0006] To achieve the above-mentioned purpose, an embodiment of the present invention provides a method for reinforcing a hard rock mined chamber by a support method, comprising: surveying and measuring the chamber to determine the positions of multiple supporting piers on the bedrock surface of the chamber; setting bottom anchor rods at the locations of the supporting piers on the bedrock surface of the chamber, and pouring concrete to the designed elevation to form supporting piers; trimming the top rock surface of the chamber corresponding to the supporting piers so that the top rock surface is low at the location of the supporting piers and high around the location of the supporting piers; pouring concrete on the top ends of multiple supporting piers to form a top beam, and the top beam is partially embedded in the top rock surface of the chamber and adapted to the shape of the top rock surface.

[0007] In one or more embodiments of the present invention, a top anchor and a connecting anchor are arranged on the top rock surface of the chamber at positions corresponding to the positions of the supporting piers, and column reinforcement bars are arranged in the supporting piers, which are respectively connected to the bottom anchor and the connecting anchor.

[0008] In one or more embodiments of the present invention, concrete is poured on the side of the supporting pier column to form a plurality of reinforcement columns extending toward the top rock surface, and an anchor cable structure is provided between the reinforcement columns and the top rock surface.

[0009] An embodiment of the present invention provides a method for reinforcing a hard rock mined-out chamber by a support method, comprising: hardening of shallow silt; positioning of support piers; building of a construction platform and a construction environment; setting of anchor rods at the top of support piers; excavation of immersed tube grouting holes and sinking of casings; setting of anchor rods at the bottom of support piers; casting of support piers; treatment of the top rock surface corresponding to the top beam of the support piers; and grouting of reserved grouting ports at the top beam of the support piers.

[0010] In one or more embodiments of the present invention, the shallow sludge hardening includes: surface zoning drainage and hardening of the chamber sludge and laying of formwork, crushed stone cushion and concrete cushion, loading and settlement detection of the concrete cushion.

[0011] In one or more embodiments of the present invention, the positioning of the supporting piers includes: after the settlement test is qualified, surveying and measuring the surface layer of the sludge in the goaf chamber, and positioning the supporting piers on the concrete cushion layer.

[0012] In one or more embodiments of the present invention, the construction platform and construction environment are constructed including: tying steel bars on a concrete cushion layer, reserving positions for supporting piers, pouring concrete slabs, and hardening the road surface to form a construction platform; spraying and anchoring the top rock surface and surrounding rock surface of the goaf chamber construction area to form a protective layer to build a construction environment.

[0013] In one or more embodiments of the present invention, the immersed tube grouting hole is excavated and the casing is sunk; anchor rods are set at the bottom of the supporting pier column; the casting of the supporting pier column includes: vertically excavating the immersed tube grouting hole into the silt at the positioning position of the supporting pier column until the hole depth reaches the designed elevation, sinking the casing, draining the sludge and cleaning the casing after the casing touches the bottom, and then pouring a certain amount of concrete to form the bottom of the supporting pier column to prevent water in the silt from entering the casing; after the concrete solidifies, the water in the immersed tube grouting hole is drained, and embedded anchor rods are driven into the solidified concrete, and the anchoring depth of the anchor rods is sufficient to pass through the solidified concrete and penetrate a certain distance into the bedrock surface; sinking the reinforced cage of the immersed tube grouting pile and connecting it with the anchor rods, and pouring concrete to the designed elevation to form the pier body of the supporting pier column.

[0014] In one or more embodiments of the present invention, the top rock surface corresponding to the supporting pier column top beam is processed; the grouting of the reserved grouting port of the supporting pier column top beam includes: trimming the top rock surface of the chamber corresponding to the supporting pier column, so that the top rock surface is low at the supporting pier column and high around the supporting pier column; after the concrete strength of the pier body of the supporting pier column reaches the design requirement, the pier top is reinforced by grouting, so that the gap on the pier top is filled with cement slurry to form the supporting pier column top beam, the supporting pier column top beam matches the top rock surface of the chamber, and is low at the connection with the supporting pier column and high away from the connection with the supporting pier column; a grouting port is set at the high point of the supporting pier column top beam, and a vibration port is set on the supporting pier column top beam, and the slurry is stirred and poured into the supporting pier column through the grouting port through the grouting port through the grouting pump, and the slurry is homogenized from the vibration port, and the injection is stopped after the design pressure is reached.

[0015] An embodiment of the present invention also provides a hard rock mined chamber support structure, including supporting piers, a plurality of the supporting piers are arranged in parallel and supported between the bedrock surface and the top rock surface of the mined chamber, anchor rods are arranged between the supporting piers and the bedrock surface of the mined chamber, anchor rods and anchor cables are arranged between the supporting piers and the top rock surface of the mined chamber, the side surface of each of the supporting piers extends toward the top rock surface to form a plurality of reinforcing columns that abut against the top rock surface, a top beam structure is arranged on the top of the plurality of supporting piers, the top beam structure is embedded in the top rock surface, and presents a structural setting in which the connection with the supporting piers is low and the connection away from the supporting piers is high.

[0016] Compared with the prior art, the method of reinforcing hard rock mined-out chambers by the support method in the embodiment of the present invention adopts support piers, and the support piers are well connected with the top rock surface and the bedrock surface to form an integral support structure, thereby improving the support quality. Compared with traditional mined-out control methods, this method greatly shortens the construction period, improves construction efficiency, and can save a lot of manpower, material resources and financial resources in terms of time and materials. It has great economic advantages and can achieve better economic benefits.

[0017] The method for reinforcing a hard rock mined-out chamber by the support method in the embodiment of the present invention is used for underground chambers with a large span and a thick layer of silt. A silt solidifier is used to harden and seal the silt surface in sections, and then a reinforced concrete slab is poured. Inverter filter bags are set up around the sludge to drain the silt. Afterwards, a load is applied and the surface displacement is monitored to build a platform that meets the needs of upper construction machinery and personnel operations. This silt treatment method can effectively deal with silt formation problems and has low cost and fast construction.

[0018] The method for reinforcing a hard rock goaf chamber by the support method of the embodiment of the present invention adopts a pipe sinking construction, the pipe sinking passes through a thick layer of silt to the complete bedrock surface, and adopts a bottom anchoring method to solve the connection problem between the bottom of the pier column and the bedrock surface of the goaf chamber. In order to strengthen the connection between the top of the column and the top rock surface, an anchor rod is set on the top rock surface, and the anchor rod is welded to the column reinforcement, so that the column and the rock layer of the top rock surface can be well connected together to form a whole.

[0019] The method of reinforcing a hard rock mined chamber by the support method according to the embodiment of the present invention adopts a cantilevered support with an eaves on the top of the supporting pier due to the irregularity of the top rock surface of the mined chamber, and the top rock surface is plane-processed in conjunction with the pier top beam. The top rock surface is slightly trimmed to be high in the middle of the beam, low at the pier, and high at the cantilevered end, similar to a "W" form (low at the pier and high around the pier), and the pier top beam is made to enter the top rock surface by 3-5 cm, which can fix the side form and prevent leakage.

[0020] The hard rock mined chamber support structure of the implementation mode of the present invention organically integrates active and passive supports, adopts pier support (active support), and the top sides extend toward the top rock surface (passive support). The top of the column is integrated with the top rock surface by anchor rods and anchor cables to achieve fixed connection, forming a "protective" type of stable active and passive integrated support system, making the support structure more stable.

[0021] The hard rock mined cavern support structure of the implementation mode of the present invention is anchored at the bottom and supported by columns at the top. The bottom anchoring method of the immersed tube construction is used to solve the connection problem between the bottom of the pier column and the bedrock surface. At the same time, an anchor rod is arranged on the top of the column and welded to the column steel bar, so that the column is well connected to the rock layer to form a whole. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a flow chart of a method for reinforcing a hard rock mined-out chamber by a support method according to an embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of the processing of the interface between the top of the supporting pier column and the top rock surface in the method for reinforcing a hard rock mined-out chamber by the supporting method according to one embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram of a hard rock goaf chamber support structure according to one embodiment of the present invention; DETAILED DESCRIPTION

[0025] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0026] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0027] In the prior art, the commonly used reinforcement method for underground mined chambers is generally the pouring and filling method. However, the reinforcement effect for underground chambers with large spans and thick layers of silt is not ideal and the treatment cost is extremely high. It is also restricted by various factors (such as the inability of equipment to enter the reinforced chamber, etc.), and it is extremely difficult to reinforce the underground chamber. The present invention creatively proposes a reinforcement method for underground chambers with large spans and thick layers of silt, which has the advantages of saving materials and low cost while ensuring reliability. It also verifies the reliability of pier support reinforcement of underground mined chambers to a certain extent through examples, and enriches related engineering cases. It plays a good demonstration role in the reinforcement of chambers under similar conditions.

[0028] like Figure 1 As shown, an embodiment of the present invention provides a method for reinforcing a hard rock cavern by a support method, which is suitable for the reinforcement project of a hard rock cavern, and is particularly suitable for the reinforcement of a hard rock cavern with a small working space and a thick layer of silt. The method includes: hardening of shallow silt s1; positioning of support piers s2; construction platform and construction environment construction s3; setting of anchor rods at the top of support piers s4; excavation of sinking pipe grouting holes and sinking of casing s5; setting of anchor rods at the bottom of support piers s6; casting of support piers s7; treatment of the top rock surface corresponding to the top beam of the support piers s8; grouting of the reserved grouting ports at the top beam of the support piers s9; and stress monitoring s10.

[0029] Underground mined chambers are usually filled with silt due to long-term non-use. People and machinery cannot enter and there is a great danger. Therefore, it is necessary to first harden the shallow silt in the mined chamber. The specific treatment method is as follows: The silt in the mined chamber is solidified and sealed in sections, and the length of each section is controlled to be 15 to 20 meters. Drain the surface of the silt in the treatment section, and then spray the silt curing agent on the surface of the silt to form a 20cm hard shell on the surface, which is convenient for later construction. Set up a filter layer on the silt hard shell, lay a single-layer formwork, and then lay a 10cm thick gravel cushion. Pour a 15cm thick plain concrete cushion and bury a vertical PVC pipe to ensure that groundwater can be discharged under capillary action. Load and test the settlement of the concrete cushion. Further construction can be carried out only after the settlement value meets the requirements.

[0030] The bedrock surface of the goaf chamber (the surface at the bottom of the silt) is uneven, and there are isolated rocks in the silt. In order to ensure smooth construction and reduce the risk of uneven bedrock surface at the bottom of the supporting piers, after the settlement value meets the requirements, it is necessary to survey and measure the immersed tube area (below the concrete cushion layer) and position the supporting piers s2. The specific processing methods are as follows: After the construction of the concrete cushion layer is completed, the geological conditions of the immersed tube pouring area are designed in advance, and the position area of ​​the supporting piers is comprehensively determined. The exploration is carried out area by area to find out the karst development under the support pier position area, and the silt thickness and the bottom flatness are explored. The support piers are positioned in the preferred flat position, and the spacing and position of the support piers can be adjusted appropriately.

[0031] After the position of the supporting pier is determined, the construction platform and construction environment can be built. The specific treatment method is as follows: after the silt solidifies and is monitored, if the settlement value meets the requirements, the steel bars are tied, the position of the supporting pier is reserved, the concrete slab is poured to seal the silt, and the concrete is cured to harden the road surface to form the pier and sprayed anchor construction platform. In order to prevent the top rock surface and the surrounding rock surface from being unstable and the block rock from falling during the construction process, the construction area of ​​the goaf chamber needs to be reinforced with sprayed anchors. First, the anchor rod construction is carried out. After the construction is completed, the mesh is hung and sprayed concrete is sprayed to form a protective layer to build the construction environment.

[0032] Subsequently, the support pier column top anchor setting s4 is carried out, which specifically includes: setting the column top anchor and pier column connecting anchor at the position corresponding to the top rock surface and the support pier column position. The column top anchor is embedded in the rock with a depth of 1.0m, and the end can be welded to the column steel bar at a later stage.

[0033] After the construction platform and construction environment are built, large equipment can be used to excavate the immersed pipe grouting hole and sink the casing. The specific treatment method is as follows: continue drilling under the action of mud wall protection until the designed elevation of the hole depth. In order to prevent the upper part of the hole from collapsing during the drilling process, a steel casing with a diameter greater than the designed hole diameter and a length of about 1.5 to 4 meters is set at the hole mouth. During the drilling process, attention should be paid to the mud consistency and the verticality of the drilling. Once the drilling hole is found to be tilted, it should be corrected by backfilling gravel in time. After the drilling is completed, the casing is hoisted and sunk in sections. Each section is 2 meters long. Gas shielded welding is used for docking. A 45° groove is made at the docking position. The butt welding seam is required to be full, free of bubbles, leaks, and water leaks. The casing sinks to the bedrock surface and an impact drill is used to clean the bottom. Super elastic rubber made of EPDM is set at the bottom of the first section of the casing to ensure that the first section of the casing that is lowered to the bottom is in close contact with the bedrock surface. After the casing is installed, the top surface of the casing is kept 0.3-0.5m above the ground of the construction platform. Reverse circulation is used to discharge mud, and the thick slurry is dehydrated by filter pressing. The water is recycled and the waste is returned to the sludge. After the casing is installed in place, the hole is cleaned with water. After the hole is cleaned, a certain amount of underwater concrete is poured to form the bottom of the supporting pier column. Pouring underwater concrete (1.0m) ensures that the water pressure effect is achieved to prevent the water in the sludge from entering the casing.

[0034] After the concrete solidifies, observe the water level changes regularly. If there is no change in the water level, it can be determined to be sealed. Then, the bottom anchor rods of the supporting pier columns can be set. The specific processing method is as follows: After the underwater concrete is initially solidified, remove the casing with the hole mouth above the ground, drain the water in the hole, and use manual work to drive the embedded anchor rods into the solidified concrete. The anchor rod is anchored to a depth that meets the requirements of passing through the solidified concrete (1.0m) and ensuring that it is deep enough into the bedrock surface for a certain distance, which is about 1.1m. After the concrete at the bottom of the immersed tube is sealed, a drill is used to take the core. A core hole is set under each pier to verify and test the sediment at the bottom of the pile.

[0035] After the anchor rods at the bottom of the supporting pier column are set, the supporting pier column can be cast s7. The specific processing methods are as follows: After the anchor rods at the bottom of the pier column are constructed, the column reinforcement is tied. When tying the reinforcement, attention should be paid to taking protective measures for the anchor rods, and the column reinforcement is connected to the anchor rods. Alternatively, after the anchor rods at the bottom of the pier column are constructed, the steel cage of the cast-in-place pile is sunk (equivalent to the already tied column reinforcement), the anchor rod port is connected to the steel cage of the cast-in-place pile, and concrete is poured to the designed elevation to form the supporting pier column body. Monitoring instruments are installed at the top of the column, and a string-type earth pressure box is set at the same time to monitor the stress state between the pier column body and the top rock surface.

[0036] After the pier body is cast, the top beam of the supporting pier can be cast. In the meantime, in order to ensure the stability between the supporting pier and the top rock surface, the top rock surface corresponding to the top beam of the supporting pier needs to be processed first. The specific processing method is as follows: After the concrete strength of the pier body reaches the design requirements, the pier top is reinforced by grouting, so that the gap on the pier top is filled with cement slurry to form the top beam of the supporting pier. Before casting the top beam, the top rock surface of the chamber corresponding to the supporting pier is trimmed to form a depression on the top rock surface. The depth of the depression is about 3-5cm, which can fix the side formwork to prevent leakage. The top rock surface in the depression is low at the supporting pier and high around the supporting pier (that is, the top beam is high in the middle, low at the column pier, and high at the outer end of the top beam in a W form). Figure 2 As shown. Grouting port 121 is set at the high point of the top beam of the supporting pier column, and vibrating port 122 is set on the top beam of the supporting pier column. Then, grouting reinforcement is carried out on the top of the pier. 42.5 micro-expansive pure cement slurry is used for grouting, and the water-cement ratio is 1:1.0-1:1.5. The slurry is stirred and poured into the supporting pier column through the grouting port by a grouting pump, and homogenized from the vibrating port. The injection can be stopped only after reaching the design pressure, and it can be re-injected after an interval of 24 hours. The formed top beam of the supporting pier column matches the top rock surface of the cavern, and is set up in a structure that is low at the connection with the supporting pier column and high away from the connection with the supporting pier column.

[0037] After the construction of the supporting pier is completed, the stress state between the column and the top rock surface is monitored in real time through the cloud platform, and the surface settlement and displacement are monitored and warned.

[0038] The method of reinforcing a hard rock mined chamber by the support method in the present invention is suitable for the reinforcement project of a hard rock mined chamber, and is particularly suitable for the reinforcement of a hard rock mined chamber with a small working space and a thick layer of silt. For a hard rock mined chamber without a thick layer of silt, the steps of hardening the silt to form a construction platform and pouring the pipes in the silt can be omitted, and the following operations can be directly adopted: survey and measure the chamber to determine the positions of multiple supporting piers on the bedrock surface of the chamber; set bottom anchor rods at the positions of the supporting piers on the bedrock surface of the chamber, and pour concrete to the designed elevation to form supporting piers; trim the top rock surface of the chamber corresponding to the supporting piers, so that the top rock surface is set in the form of low where the supporting piers are located and high around where the supporting piers are located; pour concrete on the tops of multiple supporting piers to form a top beam, and the top beam part is embedded in the top rock surface of the chamber and matches the shape of the top rock surface. The specific process steps are the same as those for reinforcing a hard rock mined chamber with a thick layer of silt, and will not be further elaborated here.

[0039] like Figure 2 and Figure 3As shown, the present invention also provides a hard rock goaf chamber support structure, including support piers 10, multiple support piers 10 are arranged in parallel and supported between the bedrock surface a and the top rock surface b of the goaf chamber, bottom anchor rods 20 are arranged between the support piers 10 and the bedrock surface a of the goaf chamber, top anchor rods 30 and anchor cables are arranged between the support piers 10 and the top rock surface b of the goaf chamber, the side of each support pier 10 extends toward the top rock surface b to form multiple reinforcement columns 11 that abut against the top rock surface b, top beam structures 12 are arranged on the tops of the multiple support piers 10, and the top beam structures 12 are embedded in the top rock surface b, and present a structural setting with a low connection with the support piers 10 and a high connection away from the support piers 10. A pressure box 40 is also arranged on the top of the support pier 10 to monitor the stress state between the column and the top rock surface.

[0040] Furthermore, the supporting pier 10 may include an upper supporting pier 102 and a lower supporting pier 101, wherein the lower supporting pier 101 is supported between the bedrock surface a and the silt surface construction platform c, and the upper supporting pier 102 is supported between the silt surface construction platform c and the top rock surface b, and anchor rods (not shown) are also connected between the upper supporting pier 102 and the lower supporting pier 101 to enhance the bonding force and improve the strength.

[0041] Compared with the prior art, the method of reinforcing hard rock mined-out chambers by the support method in the embodiment of the present invention adopts support piers, and the support piers are well connected with the top rock surface and the bedrock surface to form an integral support structure, thereby improving the support quality. Compared with traditional mined-out control methods, this method greatly shortens the construction period, improves construction efficiency, and can save a lot of manpower, material resources and financial resources in terms of time and materials. It has great economic advantages and can achieve better economic benefits.

[0042] The method for reinforcing a hard rock mined-out chamber by the support method in the embodiment of the present invention is used for underground chambers with a large span and a thick layer of silt. A silt solidifier is used to harden and seal the silt surface in sections, and then a reinforced concrete slab is poured. Inverter filter bags are set up around the sludge to drain the silt. Afterwards, a load is applied and the surface displacement is monitored to build a platform that meets the needs of upper construction machinery and personnel operations. This silt treatment method can effectively deal with silt formation problems and has low cost and fast construction.

[0043] The method for reinforcing a hard rock goaf chamber by the support method of the embodiment of the present invention adopts a pipe sinking construction, the pipe sinking passes through a thick layer of silt to the complete bedrock surface, and adopts a bottom anchoring method to solve the connection problem between the bottom of the pier column and the bedrock surface of the goaf chamber. In order to strengthen the connection between the top of the column and the top rock surface, an anchor rod is set on the top rock surface, and the anchor rod is welded to the column reinforcement, so that the column and the rock layer of the top rock surface can be well connected together to form a whole.

[0044] The method of reinforcing a hard rock mined chamber by the support method according to the embodiment of the present invention adopts a cantilevered support with an eaves on the top of the supporting pier due to the irregularity of the top rock surface of the mined chamber, and the top rock surface is plane-processed in conjunction with the pier top beam. The top rock surface is slightly trimmed to be high in the middle of the beam, low at the pier, and high at the cantilevered end, similar to a "W" form (low at the pier and high around the pier), and the pier top beam is made to enter the top rock surface by 3-5 cm, which can fix the side form and prevent leakage.

[0045] The hard rock mined chamber support structure of the implementation mode of the present invention organically integrates active and passive supports, adopts pier support (active support), and the top sides extend toward the top rock surface (passive support). The top of the column is integrated with the top rock surface by anchor rods and anchor cables to achieve fixed connection, forming a "protective" type of stable active and passive integrated support system, making the support structure more stable.

[0046] The hard rock mined cavern support structure of the implementation mode of the present invention is anchored at the bottom and supported by columns at the top. The bottom anchoring method of the immersed tube construction is used to solve the connection problem between the bottom of the pier column and the bedrock surface. At the same time, an anchor rod is arranged on the top of the column and welded to the column steel bar, so that the column is well connected to the rock layer to form a whole.

[0047] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A method for reinforcing a hard rock mined-out chamber by a support method, characterized in that: include: Conduct survey and measurement of the chamber to determine the locations of multiple supporting piers on the bedrock surface of the chamber; The bottom anchor rods are set at the location of the supporting piers on the bedrock surface of the chamber, and concrete is poured to the designed elevation to form the supporting piers; The top rock surface of the chamber corresponding to the supporting pier is trimmed so that the top rock surface is lower where the supporting pier is located and higher around where the supporting pier is located; Concrete is poured on the top of multiple supporting piers to form a top beam, and the top beam is partially embedded in the top rock surface of the chamber and adapted to the shape of the top rock surface; A top anchor rod and a connecting anchor rod are arranged on the top rock surface of the chamber at positions corresponding to the positions of the supporting piers. A column reinforcement bar is arranged in the supporting piers. The column reinforcement bar is respectively connected to the bottom anchor rod, the connecting anchor rod and the top anchor rod; Concrete is poured on the side of the supporting pier to form a plurality of reinforcement columns extending toward the top rock surface, and an anchor cable structure is arranged between the reinforcement columns and the top rock surface.

2. A method for reinforcing a hard rock mined-out chamber by a support method, characterized in that: include: Shallow mud hardening; positioning of supporting piers; construction platform and construction environment construction; setting of anchor rods at the top of supporting piers; excavation of sinking pipe grouting holes and sinking of casing; setting of anchor rods at the bottom of supporting piers; casting of supporting piers; treatment of the top rock surface corresponding to the top beam of supporting piers; Grouting is performed at the reserved grouting openings of the top beam of the supporting pier column; The shallow sludge hardening includes: draining and hardening the surface of the chamber sludge in different areas and laying formwork, crushed stone cushion and concrete cushion, piling and performing settlement detection on the concrete cushion; The positioning of the supporting piers includes: after the settlement test is qualified, the surface layer of the silt in the goaf chamber is surveyed and measured, and the position of the supporting piers is positioned on the concrete cushion layer; The construction platform and construction environment construction includes: tying steel bars on the concrete cushion layer, reserving the position of the supporting piers, pouring the concrete slab, and hardening the road surface to form a construction platform; spraying and anchoring the top rock surface and the surrounding rock surface of the goaf chamber construction area to form a protective layer to ensure the construction environment; The excavation of the immersed pipe grouting hole and the sinking of the casing; the setting of the anchor rod at the bottom of the supporting pier column; and the casting of the supporting pier column include: At the location of the supporting pier, vertical excavation of the immersed pipe pouring hole is carried out into the silt until the hole depth reaches the designed elevation, and the casing is sunk. After the casing touches the bottom, the sludge in the casing is drained and the casing is cleaned, and then a certain amount of concrete is poured to form the bottom of the supporting pier to prevent water in the silt from entering the casing; After the concrete solidifies, the water in the immersed tube pouring hole is drained out, and the embedded anchor rod is driven into the solidified concrete. The anchor rod is anchored to a depth that is sufficient to penetrate the solidified concrete and penetrate a certain distance into the bedrock surface. Lower the steel cage of the cast-in-place pile or tie the steel bars of the column and connect them with the anchor rods, and pour concrete to the designed elevation to form the supporting pier column body; The top rock surface treatment corresponding to the top beam of the supporting pier column; the grouting of the reserved grouting opening of the top beam of the supporting pier column includes: The rock surface of the chamber top corresponding to the supporting pier is trimmed so that the top rock surface is low at the supporting pier and high around the supporting pier. After the concrete strength of the supporting pier body reaches the design requirements, the pier top is reinforced by grouting, so that the gap on the pier top is filled with cement slurry to form the supporting pier top beam. The supporting pier top beam matches the rock surface of the chamber top, and is low at the connection with the supporting pier and high away from the connection with the supporting pier. A grouting port is set at the high point of the top beam of the supporting pier column, and a vibration port is set on the top beam of the supporting pier column. After the slurry is stirred, it is poured into the supporting pier column through the grouting port by a grouting pump, and the slurry is homogenized from the vibration port. The injection is stopped after the design pressure is reached.

3. A hard rock mined chamber support structure formed by the method for reinforcing a hard rock mined chamber using the support method as claimed in claim 1 or 2, characterized in that: It includes supporting piers, a plurality of the supporting piers are arranged in parallel and supported between the bedrock surface and the top rock surface of the gouged chamber, anchor rods are arranged between the supporting piers and the bedrock surface of the gouged chamber, anchor rods and anchor cables are arranged between the supporting piers and the top rock surface of the gouged chamber, the side surface of each supporting pier extends toward the top rock surface to form a plurality of reinforcing columns that abut against the top rock surface, a top beam structure is arranged on the top of the plurality of supporting piers, the top beam structure is embedded in the top rock surface, and presents a structural setting that is low at the connection with the supporting piers and high away from the connection with the supporting piers.

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