Trapezoidal roadway supporting structure and supporting method

Abstract

The invention relates to a trapezoidal roadway supporting structure and a supporting method.The preset position of a trapezoidal roadway is provided with a point column structure used for supporting, and the point column structure comprises a plurality of barren rock bodies and foam concrete filled in gaps among the barren rock bodies. Therefore, the point-column structure adopts the mine waste rocks as the main aggregate and is matched with the foam concrete for cementing, so that the resource recycling of the waste rocks is realized, and the procurement cost of the support material is reduced; the barren rock main body plays a role in framework supporting, the foam concrete fills gaps and is cemented with the barren rock, the overall compressive strength of the point-column structure is improved, internal extrusion deformation of a trapezoidal roadway side wall can be effectively resisted, and the roadway supporting stability is guaranteed; the point column structure is composed of the waste rock main body and the foam concrete, a complex processing technology is not needed, during construction, only the waste rock needs to be piled at a preset position, then the foam concrete is poured to fill gaps, and the construction efficiency can be greatly improved.

Description

Technical Field

[0001] This disclosure relates to the field of mining technology, and more specifically, to a trapezoidal roadway support structure and support method. Background Technology

[0002] In underground engineering fields such as mining and tunneling, roadways serve as the core passageways for personnel, equipment transportation, and ventilation, and their support stability directly affects construction safety and operational efficiency. With increasing mining depth, expanded mining scale, and rising engineering demands under complex geological conditions, the application of ultra-wide roadways is becoming increasingly widespread. Compared to conventionally wide roadways, ultra-wide roadways have a larger cross-sectional span, significantly increasing the pressure on the roof and sidewalls from the surrounding rock, leading to more pronounced stress concentration and a substantial increase in support difficulty.

[0003] Trapezoidal cross sections are widely used in the design of ultra-wide tunnels due to their advantages such as reasonable stress distribution, convenient construction, and strong adaptability to surrounding rock deformation. Currently, the support technologies for trapezoidal ultra-wide tunnels mainly include traditional shed support (such as I-beam sheds and U-shaped sheds), bolt-cable combined support, shotcrete support, and combinations of the above methods.

[0004] However, existing support technologies still have many shortcomings in practical applications: First, although traditional shed-type supports have high initial support strength, they are heavy, cumbersome to install, and have poor adhesion to the surrounding rock, making it difficult to effectively transfer and disperse the pressure of the surrounding rock. Long-term use can easily lead to risks such as shed deformation and collapse, especially under soft and fractured surrounding rock conditions where stability is insufficient. Second, conventional anchor bolt-anchor cable combined supports often adopt a uniform arrangement, failing to fully consider the stress distribution differences in different areas of the trapezoidal cross-section (the middle of the roof, the shoulder of the roof, the upper part of the two sides, etc.). This results in a mismatch between the support strength and the stress on the surrounding rock, insufficient support in key stress concentration areas, and redundant support in non-critical areas, causing waste of support materials and failing to guarantee overall support. Third, the existing combined support technology has poor synergy among its various support components. For example, the shotcrete layer is not tightly bonded to the anchor bolts and cables, failing to form an integrated support system. This makes it difficult to fully utilize the synergistic load-bearing capacity of each support component, which can easily lead to local failures during periods of intense deformation of the surrounding rock, thus causing instability of the overall support system. Fourth, for trapezoidal ultra-wide tunnels in deep mining or under high-stress geological conditions, the deformation control capability of the existing support technology is limited, making it difficult to adapt to the large deformation characteristics of the surrounding rock. Problems such as roof subsidence and inward squeezing of the sidewalls are prone to occur, requiring frequent post-construction maintenance and reinforcement, which increases project costs and affects construction progress. Fifth, the existing support materials are too expensive and inefficient, slowing down the construction progress. Summary of the Invention

[0005] The purpose of this disclosure is to provide a trapezoidal roadway support structure and support method to at least partially solve the problems existing in the related technologies.

[0006] To achieve the above objectives, this disclosure provides a trapezoidal tunnel support structure, wherein a point column structure for support is provided at a predetermined position of the trapezoidal tunnel, and the point column structure includes multiple waste rock bodies and foamed concrete filling the gaps between the multiple waste rock bodies.

[0007] In some possible implementations, the preset position is located below the inclined side surface of the trapezoidal tunnel.

[0008] In some possible implementations, the width of the point column structure is 0.3m to 0.8m, and the spacing between two adjacent point column structures along the ore body is 1.5m to 3.0m.

[0009] In some possible implementations, the uniaxial compressive strength of the point column structure is 1 MPa to 6 MPa.

[0010] In some possible implementations, the trapezoidal tunnel support structure further includes baffles for stopping the point column structure at predetermined positions.

[0011] According to a second aspect of the present disclosure, a method for supporting a trapezoidal roadway is provided. The method employs the aforementioned trapezoidal roadway support structure and includes the following steps:

[0012] S1: Determine the condition of the trapezoidal roadway to be supported and the surrounding mine rock; S2: Based on the conditions of the trapezoidal tunnel and the surrounding mine rock, determine the parameters of the waste rock main body and foamed concrete in the main body of the aforementioned column structure; and S3: Place the waste rock pile at the preset position of the trapezoidal tunnel, pour foamed concrete into the main pile of waste rock, and form the point column structure after cementing and curing.

[0013] In some possible implementations, in step S1, The steps for determining the condition of the trapezoidal roadway to be supported include: measuring the bottom width, top width, height, and the angle of the side slope of the trapezoidal roadway. The steps for determining the condition of the surrounding rock of the mine include: detecting the loosened zone of the surrounding rock in the trapezoidal tunnel using ground penetrating radar, and collecting joint and fracture data of the surrounding rock using laser scanning.

[0014] In some possible implementations, step S2 includes: determining the physical and mechanical parameters of the foamed concrete and the compatibility parameters between the waste rock matrix and the foamed concrete through indoor tests, and determining the material ratio of the foamed concrete based on the physical and mechanical parameters of the foamed concrete and the compatibility parameters between the waste rock matrix and the foamed concrete.

[0015] In some possible implementations, step S2 and step S3 may further include: S4: Erect isolation support plates at the preset positions in the trapezoidal tunnel, lay an impermeable membrane on the inner wall of the isolation support plates, and then pile the main body of waste rock in the area enclosed by the isolation support plates.

[0016] In some possible implementations, in step S3, A vertically arranged baffle is installed on one side of the inclined sidewall of the trapezoidal roadway, and the point column structure is arranged in the area enclosed by the baffle and the inclined sidewall.

[0017] Through the above technical solution, the point-column structure uses mine waste rock as the main aggregate, combined with foamed concrete for bonding, to achieve the resource recycling and utilization of waste rock, reduce pollution from waste rock stockpiling, and lower the procurement cost of support materials. The waste rock main body acts as a skeleton support, while the foamed concrete fills the gaps and bonds the waste rock, improving the overall compressive strength of the point-column structure. It can effectively resist the inward squeezing deformation of the trapezoidal roadway sidewalls and ensure the stability of the roadway support. The point-column structure is composed of waste rock main body and foamed concrete, which does not require complicated processing technology. During construction, it is only necessary to place the waste rock in the preset position and then pour foamed concrete to fill the gaps. It is suitable for on-site construction conditions in mines and can greatly improve construction efficiency.

[0018] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of a point column arrangement scheme for a trapezoidal roadway support structure, exemplarily shown in this disclosure. Figure 2 This is a schematic diagram of a trapezoidal tunnel in a trapezoidal tunnel support structure exemplarily shown according to this disclosure; Figure 3 This is a schematic diagram of a trapezoidal tunnel support structure exemplarily shown according to this disclosure; Figure 4 This is a flowchart illustrating a trapezoidal roadway support method according to the present disclosure; Figure 5 This is a framework diagram of a trapezoidal roadway support system exemplarily shown in this disclosure.

[0020] Explanation of reference numerals in the attached figures 1-Trapezoidal tunnel; 2-Point column structure; 21-Waste rock main body; 22-Foamed concrete; 3-Baffle. Detailed Implementation

[0021] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0022] In this disclosure, unless otherwise stated, the directional terms "up" and "down" should be understood based on the application environment of the relevant components, as detailed in the relevant references. Figure 3 The drawing orientation is shown. "Inner" and "outer" refer to the outline of the corresponding component itself. In this disclosure, when the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0023] Reference Figures 1 to 3 This disclosure provides a trapezoidal tunnel support structure. A point-column structure 2 is installed at a predetermined location in the trapezoidal tunnel 1 for support. The point-column structure 2 may include multiple waste rock bodies 21 and foamed concrete 22 filling the gaps between the multiple waste rock bodies 21. The waste rock bodies 21 are generated during mining, eliminating the need for additional aggregate procurement, thus solving the environmental problem of waste rock dumping and reducing the material cost of the support structure. The foamed concrete 22 fills the gaps between the waste rock bodies 21, acting as a binder and encapsulator, allowing the multiple dispersed waste rock bodies 21 to form a unified load-bearing structure. This collaboratively resists the inward extrusion deformation force of the trapezoidal tunnel 1's sidewalls, compensating for the insufficient stability of a single waste rock support and the limited load-bearing capacity of a single foamed concrete 22. The arrangement and dimensions of the point-column structure 2 can be flexibly adjusted according to the cross-sectional dimensions of the trapezoidal tunnel 1 and the stability of the surrounding rock to adapt to the support requirements of trapezoidal tunnels 1 of different specifications.

[0024] Through the above technical solution, the point-column structure 2 uses mine waste rock as the main aggregate, combined with foamed concrete 22 for bonding, to achieve the resource recycling of waste rock, reduce pollution from waste rock stockpiling, and reduce the procurement cost of support materials. The waste rock main body 21 plays a supporting role, and the foamed concrete 22 fills the gaps and bonds the waste rock, which improves the overall compressive strength of the point-column structure 2 and can effectively resist the inward squeezing deformation of the trapezoidal roadway sidewall, ensuring the stability of the roadway support. The point-column structure 2 is composed of waste rock main body 21 and foamed concrete 22, which does not require complicated processing technology. During construction, it is only necessary to place the waste rock in the preset position and then pour foamed concrete 22 to fill the gaps. It is suitable for on-site construction conditions in mines and can greatly improve construction efficiency.

[0025] Among them, reference Figure 3 The preset position can be located below the inclined sidewall of the trapezoidal roadway 1. Specifically, the inclined sidewall of the trapezoidal roadway 1 is the main part that bears the inward squeezing deformation force of the surrounding rock. Its lower area is a stress concentration zone and is also the key part where the sidewall is most prone to deformation and collapse. Setting the point column structure 2 at this preset position can directly form bottom support for the inclined sidewall, accurately resist the inward squeezing deformation force of the sidewall, thereby inhibiting the inward displacement and collapse of the inclined sidewall into the roadway.

[0026] Furthermore, the width of point column structure 2 can be 0.3m to 0.8m, and the spacing between two adjacent point column structures 2 along the strike of the ore body can be 1.5m to 3.0m. The width of point column structure 2 is... Figure 1 The dimensions of a single point column structure 2 in the left and right directions, and the distance between two adjacent point column structures 2 refer to... Figure 1 The spacing between two adjacent point column structures 2 in the left and right directions is determined by the width of the point column structure 2, which can be determined by combining the conventional cross-sectional dimensions of the trapezoidal roadway 1, the stress distribution of the sidewalls, and the load-bearing characteristics of the waste rock body 21 and the foamed concrete 22. This width range can ensure that the point column structure 2 has sufficient cross-sectional area for bearing force, avoiding insufficient load-bearing capacity due to insufficient width, which would lead to failure and instability due to the inward squeezing deformation of the sidewalls; it can also effectively control the space occupied by the point column structure 2, avoiding the compression of the roadway passage area due to excessive width, while reducing the consumption of waste rock and foamed concrete 22 materials and lowering construction costs. The arrangement interval of 1.5m to 3.0m can avoid the construction process being cumbersome and inefficient due to the dense arrangement of point columns, and avoid the local stress concentration caused by the superposition of forces on adjacent point columns; it can also prevent the support blind spots from the arrangement of point columns being too sparse, ensuring full coverage of the stress concentration area of ​​the roadway sidewalls and effectively suppressing the overall inward squeezing deformation of the sidewalls.

[0027] Furthermore, the uniaxial compressive strength of the point column structure 2 can be 1 MPa to 6 MPa, ensuring that a single point column has sufficient load-bearing capacity. The waste rock body 21 acts as aggregate to provide skeletal support, while the foamed concrete 22 fills the gaps and binds the waste rock to form a whole. By adjusting the material ratio of the foamed concrete 22 (such as the amount of cementitious material and the water-cement ratio), the uniaxial compressive strength of the point column structure 2 can be flexibly controlled within the range of 1 MPa to 6 MPa. Without changing the size and arrangement of the point columns, it can be adapted to trapezoidal roadways 1 under different stress conditions.

[0028] According to some embodiments, refer to Figure 3 The trapezoidal tunnel support structure may also include a baffle 3 for stopping the point column structure 2 at a predetermined position. The baffle 3 can prevent the point column structure 2 from shifting due to the eccentric stacking of the waste rock body 21, the lateral pressure of the foamed concrete 22 pouring, or the squeezing force within the surrounding rock. It ensures that the point column structure 2 is always in the pre-set stress concentration area below the inclined surface of the sidewall, accurately bearing the squeezing force of the surrounding rock, eliminating the support blind zone caused by the offset of the point column structure 2, preventing chain collapse accidents caused by the initial instability of the surrounding rock, and improving the reliability of the support structure.

[0029] According to the second aspect of this disclosure, referring to Figure 4 Furthermore, a trapezoidal roadway support method is provided. This method employs the aforementioned trapezoidal roadway support structure and includes the following steps: S1: Determine the conditions of the trapezoidal roadway 1 to be supported and the surrounding mine rock; S2: Determine the parameters of the waste rock main body 21 and foamed concrete 22 based on the conditions of the trapezoidal roadway 1 and the surrounding mine rock; and S3: Place the waste rock pile at a predetermined location in the trapezoidal roadway 1, pour foamed concrete 22 onto the waste rock pile, and after curing, form a point-column structure 2. This support method effectively solves the problems of blindly arranging point columns and mismatched parameters with working conditions in existing support construction, leading to support failure or cost waste. After support, the internal deformation of the roadway sidewalls is effectively controlled, eliminating the risk of collapse.

[0030] Specifically, in step S1, the steps to determine the condition of the trapezoidal roadway 1 to be supported may include: measuring the bottom width, top width, height, and angle of the inclined surface of the sidewall of the trapezoidal roadway 1. The bottom width, top width, and height directly determine the cross-sectional specifications of the trapezoidal roadway 1, which is the basis for subsequently determining the width, height, and arrangement density of the point column structure 2; the angle of the inclined surface of the sidewall determines the direction of force and stress distribution characteristics of the internal squeezing deformation of the sidewall, which directly affects the accurate positioning of the preset position of the point column structure 2, ensuring that the point column can specifically withstand the sidewall squeezing force; the steps to determine the condition of the surrounding mine rock may include: detecting the loosened zone of the surrounding rock of the trapezoidal roadway 1 by ground penetrating radar, and collecting joint and fracture data of the surrounding rock by laser scanning. To determine the surrounding rock conditions of the mine, a combination of ground-penetrating radar (GPR) and laser scanning is used to achieve accurate detection of surrounding rock information. GPR can quickly and efficiently detect the thickness and distribution range of the loosened zone of the surrounding rock, identify unstable areas of the surrounding rock, and provide a basis for the strength parameters and layout of the subsequent point column structure 2, avoiding the placement of point columns within the loosened zone of the surrounding rock, which could lead to support failure. Laser scanning can accurately collect data such as the distribution density and extension direction of joints and fissures in the surrounding rock, clarifying the integrity of the surrounding rock. If the joints and fissures in the surrounding rock are dense and the integrity is poor, the spacing of the point columns can be adjusted and the strength of the point columns can be increased in subsequent steps to ensure the reliability of the support.

[0031] Specifically, step S2 may include: determining the physical and mechanical parameters of foamed concrete 22 and the compatibility parameters between waste rock matrix 21 and foamed concrete 22 through indoor tests; and determining the material proportions of foamed concrete 22 based on the physical and mechanical parameters of foamed concrete 22 and the compatibility parameters between waste rock matrix 21 and foamed concrete 22. The material proportions may include the amount of cementitious materials, water-cement ratio, foam content, and admixture content. Through indoor tests, the physical and mechanical parameters of foamed concrete 22 can be determined, including but not limited to dry apparent density, uniaxial compressive strength at 7 days and 28 days, modulus of elasticity, water absorption rate, and drying shrinkage rate. These parameters directly determine the bonding performance, load-bearing capacity, and deformation characteristics of foamed concrete 22, and are the basis for ensuring the overall strength of the point column structure 2. Meanwhile, indoor tests can determine the compatibility parameters of the waste rock main body 21 and foamed concrete 22, mainly including the waste rock content, waste rock particle size distribution, bonding strength between foamed concrete 22 and waste rock, and foam stability. These compatibility parameters directly affect the stress effect of waste rock and foamed concrete 22, avoiding problems such as weak bonding between waste rock and foamed concrete 22, delamination and detachment, or insufficient bearing capacity of point column structure 2, thus ensuring the stability of point column structure 2.

[0032] The strength and physical and mechanical properties of the waste rock-foamed concrete composite filling were measured using indoor tests and other methods. Specifically, 100mm×100mm×100mm cubic specimens were used, and when the maximum particle size of the waste rock was controlled to not exceed 31.5mm, the ratio of the maximum waste rock particle size to the length of the filling specimen was approximately equal to the ratio of the maximum waste rock block size to the size of the filling body per unit volume, showing good similarity.

[0033] Crushed waste rock, used as coarse aggregate, was mixed with fine foamed concrete 22 for cementation and filling. Crushed waste rock, composite silicate cement, and natural water were mixed in appropriate proportions to form foamed concrete 22 with densities of approximately 500 kg / m³ and 700 kg / m³, respectively. After the foamed concrete 22 was thoroughly mixed, each spoonful of filling slurry was quickly and evenly poured into a square mold in sequence. After the slurry initially set, the surface of the mold was smoothed. After 24 hours, the mold was demolded, and the test blocks were placed in a standard curing chamber for curing (curing temperature and humidity adjusted to 20℃ and 93%, respectively). After curing for 7 days and 28 days, the mass of each test block was measured to an accuracy of 0.1 g, and then used as samples for uniaxial compression tests.

[0034] The test was conducted using a triaxial rock and soil pressure machine. Since the strength of the filling material is lower than that of rock and concrete, the vertical output of the vertical hydraulic cylinder of the pressure machine was selected to be 100kN. The test error was only 0.3kN. The accuracy and error of the test system are feasible in the uniaxial compressive strength test of the filling material. The test loading adopted the displacement control mode. Three samples were tested in each group, and the average value of the three samples was taken as the test result.

[0035] By measuring the strength data of the waste rock foamed concrete filling body 22 and considering the specific conditions of the mine site, a suitable material ratio is selected to ensure the strength of the filling body while saving costs.

[0036] The point column layout of a trapezoidal ultra-wide tunnel was simulated using FLAC3D numerical simulation software to optimize the layout scheme. A numerical simulation model was constructed using the Mohr-Coulomb constitutive model, with previously obtained data used as parameters. These parameters included: bulk modulus, shear modulus, internal friction angle, cohesion, unit weight, and tensile strength. The stability of different point column layout schemes was simulated, and the control effect of different layout schemes on ground stress was analyzed to select the optimal point column width and spacing.

[0037] In some embodiments, step S4 is further included between steps S2 and S3: An isolation support plate is erected at a predetermined position in the trapezoidal tunnel 1, and an impermeable membrane is laid on the inner wall of the isolation support plate. Waste rock is then piled within the area enclosed by the isolation support plate. The erection of the isolation support plate must strictly conform to the predetermined position and dimensional parameters of the point column structure 2 determined in step S2. The isolation support plate uses a material with suitable strength (such as steel plate or wooden support plate). The dimensions of the enclosed area after erection match the cross-sectional width and height of the point column structure 2, ensuring accurate placement of waste rock and preventing it from scattering outside the predetermined area. Simultaneously, it limits the pouring range of the foamed concrete 22, preventing slurry overflow during pouring and ensuring the cross-sectional forming accuracy of the point column structure 2. The isolation support plate must be firmly erected, with its bottom tightly fitted to the tunnel floor and its sides fitted to the inclined surface of the tunnel sidewall. Temporary fasteners can be used for reinforcement to prevent displacement or collapse during construction, ensuring operational safety.

[0038] The anti-permeability membrane is laid on the inner wall of the isolation support plate. A flexible membrane material that is waterproof and prevents grout penetration is selected. During the laying, it must be flat, undamaged, and wrinkle-free to ensure that the inner wall of the isolation support plate is fully covered. The joints are sealed to prevent the foam concrete grout from seeping to the outside of the isolation support plate, avoid direct contact between the grout and the surrounding rock of the roadway and cause pollution, and prevent the grout from flowing out and causing insufficient density of the foam concrete 22, so as to ensure the overall strength and bonding effect of the point column structure 2.

[0039] After the isolation support plate is erected and the anti-permeability membrane is laid, the waste rock that meets the particle size parameters determined in step S2 is evenly piled in the area enclosed by the isolation support plate. During the piling process, it can be slightly leveled to ensure that the waste rock pile is evenly distributed and without obvious voids, so as to provide a good foundation for the subsequent pouring of foam concrete 22 and filling of gaps.

[0040] In some embodiments, in step S3, a vertically arranged baffle 3 can be installed on one side of the inclined sidewall of the trapezoidal tunnel 1, and the point column structure 2 is arranged in the area enclosed by the baffle 3 and the inclined sidewall. The vertical baffle 3 serves as an auxiliary limiting component for the point column structure 2. Its top end corresponds to the junction of the inclined sidewall and the top plate of the trapezoidal tunnel 1, and its bottom end extends to the bottom plate of the trapezoidal tunnel 1. It is arranged vertically and fits tightly with the tunnel top plate, the inclined sidewall, and the bottom plate. It can be firmly connected to the surrounding rock and the bottom plate through fasteners such as expansion bolts to ensure its own structural stability. It can effectively resist the lateral forces of the point column structure 2 and the foamed concrete 22 and prevent itself from shifting or tilting.

[0041] Specifically, the baffle 3 is a permanent limiting structure arranged below the junction of the inclined surface of the sidewall and the roof of the trapezoidal tunnel 1. It extends along the direction of the trapezoidal tunnel 1 and covers the arrangement area of ​​the entire row of point column structures 2. Its function is to stop the entire point column structure 2 within the preset area below the inclined surface of the sidewall, preventing the point column structure 2 from shifting into the trapezoidal tunnel 1 during construction pouring or the stress stage of the surrounding rock, and ensuring that the point column structure 2 is always in the stress concentration area to accurately bear the extrusion pressure of the sidewall. The isolation support plate is a temporary construction component erected in the area enclosed by the baffle 3 and the inclined surface of the sidewall. It forms a frame-like closed space only around the preset position of a single point column structure 2. Its function is to limit the cross-sectional size of the single point column structure 2, prevent waste rock from scattering and foamed concrete grout from leaking out. It can be removed after the foamed concrete has solidified and does not participate in the subsequent support stress.

[0042] The proposed trapezoidal ultra-wide tunnel support method first involves preliminary data collection, including the detection of loosened zones and joint fissures in the surrounding rock using ground-penetrating radar and laser scanning. Laboratory tests are then conducted to determine the strength of the waste rock main body 21 and foamed concrete 22 used for support. Based on this information, a layout scheme for the point-column structure 2 is designed, and numerical simulation analysis is performed using FLAC3D software to compare the ground stress control effects of different schemes. The final layout scheme is then determined, and construction proceeds to support the trapezoidal ultra-wide tunnel. This method offers high support efficiency, low support cost, and effective control of inward squeezing on the inclined surface of the trapezoidal tunnel sidewalls.

[0043] According to the third aspect of this disclosure, referring to Figure 5 Furthermore, a support system for implementing the above-described trapezoidal roadway support method is provided, the support system comprising: The data collection module is used to collect data on the dimensions of trapezoidal tunnel 1 and the physical and mechanical properties of the surrounding rock. The collected dimensional data for trapezoidal tunnel 1 includes the bottom width, top width, height, and the angle of the sidewall inclination. The collected physical and mechanical property data for the surrounding rock includes cohesion, internal friction angle, elastic modulus, Poisson's ratio, and stress level, providing fundamental data for subsequent laboratory tests and numerical simulations. This data collection module can interface with laser scanning equipment and mine geological exploration systems to achieve automatic data acquisition and processing, avoiding errors caused by manual data collection.

[0044] The on-site detection module is used to perform ground-penetrating radar (GPR) and laser scanning on the surrounding rock to acquire data on the loosened zone and joints / fractures. GPR scanning can quickly and accurately detect the thickness, distribution range, and morphology of the loosened zone, identifying unstable areas and providing a basis for optimizing the placement and strength parameters of the subsequent point column structure 2. Laser scanning can collect data on the distribution density, extension direction, and fracture width of joints and fractures in the surrounding rock with high precision, assessing the integrity of the surrounding rock and supporting the determination of parameters such as the point column spacing and waste rock particle size in step S2. This on-site detection module can flexibly adapt to the mining site environment, enabling real-time detection and data upload of the surrounding rock conditions, ensuring that the detection results can promptly serve the subsequent parameter design stage.

[0045] The filling data module is used to organize and analyze preliminary test and detection data to determine the cement-sand ratio, concentration, and material proportions of the foamed concrete 22 required for the support. The filling data module receives all basic data from the data collection module and the field detection module, and integrates the physical and mechanical parameters of the foamed concrete 22 obtained from indoor tests, as well as the adaptation parameters of the waste rock main body 21 and the foamed concrete 22. Through professional data processing algorithms, it classifies, organizes, analyzes, and optimizes various types of data, ultimately outputting key parameters of the foamed concrete 22 adapted to the field conditions, including the cement-sand ratio, slurry concentration, cementitious material dosage, water-cement ratio, and foam content. This directly provides a precise basis for the preparation of the foamed concrete 22 in step S3, avoiding blindly designing material proportions and ensuring that the performance of the foamed concrete 22 is precisely matched to the support requirements.

[0046] The numerical simulation module is used to simulate and analyze the layout scheme of point column structure 2, determining the cross-sectional width and spacing of point column structure 2 along the ore body strike. The module employs professional numerical simulation software such as FLAC3D to construct a numerical simulation model highly consistent with actual field conditions. The model uses the Mohr-Coulomb constitutive model, and the assigned parameters include the cohesion, internal friction angle, elastic modulus, and Poisson's ratio of the surrounding rock and waste rock body 21 and the foamed concrete 22. All assigned parameters are derived from previous exploration and experimental data. By simulating the support stability of different point column layout schemes (different cross-sectional widths and different spacing), the module analyzes the control effect of each scheme on ground stress, the stress distribution of the point columns, and the effect on surrounding rock deformation suppression, ultimately selecting the optimal layout scheme.

[0047] The point column construction module is used to place waste rock in a preset position and pour foamed concrete 22. After curing, a stable point column structure 2 is formed. The point column construction module receives point column layout parameters from the numerical simulation module and foamed concrete 22 mix proportion parameters from the filling data module. Following the construction process of steps S4 and S3, it first completes the setting of vertical baffles 3, the erection of isolation supports, and the laying of anti-permeability membranes. Then, waste rock that meets the particle size requirements is evenly piled in the preset area enclosed by baffles 3 and the inclined side surface. Subsequently, according to the determined foamed concrete 22 material mix proportion, the preparation and pouring of foamed concrete 22 are completed to ensure that the foamed concrete 22 evenly fills the gaps between waste rock. Finally, curing and control are completed until the foamed concrete 22 is cured and formed into a point column structure 2 with overall load-bearing and reliable support, improving construction efficiency and point column forming quality.

[0048] This support system solves the problems of disconnect between various links in existing support construction, blind parameter design, and insufficient construction precision. It realizes the data-driven, standardized, and precise control of the entire support construction process, further improving the support effect, construction efficiency, and economy. At the same time, it reduces the operation difficulty for construction personnel and adapts to the support needs of different surrounding rock conditions and different specifications of trapezoidal roadways, providing reliable system support for the sidewall support of trapezoidal roadways.

[0049] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0050] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0051] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A trapezoidal tunnel support structure, characterized in that, The trapezoidal tunnel is provided with a support point column structure at a predetermined position. The point column structure includes multiple waste rock bodies and foamed concrete filling the gaps between the multiple waste rock bodies.

2. The trapezoidal tunnel support structure according to claim 1, characterized in that, The preset position is located below the inclined side surface of the trapezoidal tunnel.

3. The trapezoidal tunnel support structure according to claim 1, characterized in that, The width of the point column structure is 0.3m to 0.8m, and the spacing between two adjacent point column structures along the ore body is 1.5m to 3.0m.

4. The trapezoidal roadway support structure according to claim 1, characterized in that, The uniaxial compressive strength of the point column structure is 1 MPa to 6 MPa.

5. The trapezoidal roadway support structure according to claim 1, wherein the trapezoidal roadway support structure further includes a baffle for stopping the point column structure at a predetermined position.

6. A method for supporting trapezoidal roadways, characterized in that, The support method employs the trapezoidal roadway support structure as described in any one of claims 1-5, and the support method includes the following steps: S1: Determine the condition of the trapezoidal roadway to be supported and the surrounding mine rock; S2: Based on the trapezoidal roadway and the surrounding mine rock conditions, determine the parameters of the waste rock main body and foamed concrete in the point column structure; and S3: The waste rock body is placed at the preset position of the trapezoidal tunnel, and foamed concrete is poured into the waste rock body. After curing, the point column structure is formed.

7. The trapezoidal roadway support method according to claim 6, characterized in that, In step S1, The steps for determining the condition of the trapezoidal roadway to be supported include: measuring the bottom width, top width, height, and the angle of the side slope of the trapezoidal roadway. The steps for determining the condition of the surrounding rock of the mine include: detecting the loosened zone of the surrounding rock in the trapezoidal tunnel using ground penetrating radar, and collecting joint and fracture data of the surrounding rock using laser scanning.

8. The trapezoidal roadway support method according to claim 6, characterized in that, Step S2 includes: determining the physical and mechanical parameters of foamed concrete and the compatibility parameters between waste rock and foamed concrete through indoor tests; and determining the material ratio of foamed concrete based on the physical and mechanical parameters of foamed concrete and the compatibility parameters between waste rock and foamed concrete.

9. The trapezoidal roadway support method according to claim 6, characterized in that, The steps between S2 and S3 also include: S4: Erect isolation support plates at the preset positions in the trapezoidal tunnel, lay an impermeable membrane on the inner wall of the isolation support plates, and then pile the main body of waste rock in the area enclosed by the isolation support plates.

10. The trapezoidal roadway support method according to claim 6, characterized in that, In step S3, A vertically arranged baffle is installed on one side of the inclined sidewall of the trapezoidal roadway, and the point column structure is arranged in the area enclosed by the baffle and the inclined sidewall.

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