An experimental device and method for simulating roadway deformation law in coal seam mining process

Abstract

The application discloses a kind of test device and method for simulating roadway deformation law in coal seam mining process, and relates to roadway test simulation technical field.The device includes: model test box, for simulating the actual environment in coal seam mining process;Water bag pressurization system is set in model test box, for simulating the pressurization effect in coal seam mining process;Excavation simulation pulling system is used to simulate coal seam mining process by using plate pulling movement, including plate and electric hoist hanging rod, plate is aligned with one side of roadway scale model, plate is pulled out vertically from model test box by electric hoist hanging rod to simulate the layer-by-layer mining process of coal mine;Displacement acquisition system is used to collect the deformation data of roadway in simulated coal seam mining process in model test box.The application constructs model prepared based on similarity theory and carries out pressurization, mining and monitoring test, which can quantitatively analyze the deformation and failure behavior of coal mine roadway in mining process.

Description

Technical Field

[0001] This invention relates to the field of roadway test simulation technology, and in particular to a test device and method for simulating the deformation law of roadways during coal seam mining. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The core of coal mine roadway stability research is to reveal the dynamic response mechanism of the surrounding rock-support system under mining-induced stress fields. The deformation and failure of coal mine roadways is essentially an energy release process under the coupled effects of in-situ stress, tectonic stress, and mining disturbance stress. Currently, traditional coal mine roadway detection methods mainly rely on manual inspections and limited sensor data acquisition, which suffers from shortcomings such as incomplete data acquisition, long on-site monitoring cycles, and untimely response. Furthermore, due to the lack of effective positioning methods and monitoring equipment within the mine, existing methods struggle to achieve real-time dynamic monitoring of roadway deformation processes and failure modes.

[0004] Physical similarity simulation experiments can quantitatively characterize the stress redistribution and critical instability features of roadways, overcoming the limitations of traditional empirical formulas. This provides theoretical support for optimizing support parameters in deep mining, early warning of dynamic disasters, and coordinated control of mining and tunneling, and has irreplaceable engineering guiding value for achieving safe and efficient mining throughout its entire life cycle. However, reproducing the deformation-failure laws of mining roadways under laboratory conditions still faces the following bottlenecks:

[0005] The single loading method cannot synchronously restore the coupling path of original rock stress, tectonic stress and mining disturbance, resulting in a large difference between the "stress-displacement" response and the actual situation.

[0006] The simulation of the mining process relies on manual layer-by-layer stripping, and the spatial step length and time interval are uncontrollable, making it difficult to capture the gradual destruction dynamics of the roadway as the working face advances.

[0007] The monitoring methods are limited. Traditional displacement gauges / strain gauges have few points of deployment and low frequency, and lack synchronous real-time data on confining pressure, displacement, and fracture field, so they cannot provide the critical threshold for instability.

[0008] Damage mode identification remains at the level of qualitative description, lacking a repeatable and quantifiable testing platform, which means that support optimization and disaster early warning still rely on engineering experience.

[0009] Therefore, how to reasonably simulate and systematically excavate the deformation and damage of coal mine roadways during mining operations under laboratory conditions, and carry out targeted roadway maintenance, has become an urgent technical problem to be solved. Summary of the Invention

[0010] To address the shortcomings of existing technologies, the purpose of this invention is to provide an experimental device and method for simulating the deformation behavior of roadways during coal seam mining. A model based on similarity theory is constructed and pressurization, mining, and monitoring tests are conducted, enabling quantitative analysis of the deformation and damage behavior of coal mine roadways during mining.

[0011] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0012] The first aspect of this invention provides an experimental apparatus for simulating the deformation law of roadways during coal seam mining, comprising:

[0013] The model test box is used to simulate the actual environment of the coal seam mining process, including a stratum simulation similar body and a roadway scale model. The stratum simulation similar body is used to reflect the mechanical properties and geological conditions of the strata, and the roadway scale model is used to characterize the roadway structure.

[0014] The water bladder pressurization system is set inside the model test box to simulate the pressurization effect during coal seam mining. It includes a top water bladder and side water bladders. After the top cover of the test box is closed, the top water bladder is tightly attached to the upper surface of the rock mass to form a downward vertical confining pressure loading. The side water bladders are set between the side wall of the model test box and the adjacent rock mass to form a lateral confining pressure loading into the rock mass.

[0015] Excavation simulation pull-out system is used to simulate the coal seam mining process through the movement of the pull plate;

[0016] The displacement acquisition system is used to collect deformation data of the roadway during the simulated coal seam mining process in the model test box.

[0017] Furthermore, the model experimental box is rectangular in shape and is welded from grid-shaped steel plates, with an openable top cover.

[0018] Furthermore, the model test chamber has multiple openings pre-drilled in the wall, including an inlet hole for the water bladder pressurization system, a pre-drilled opening for installing the tunnel scale model, and a through hole for the excavation simulation pull-out system.

[0019] Furthermore, the model test box has a volume three times that of the scaled-down tunnel model, and its interior is equipped with a boundary transition zone and a loading reserve zone.

[0020] Furthermore, the reserved loading area is used to arrange the side water bladders, top water bladders, and pull-out panels.

[0021] Furthermore, the excavation simulation pull-out system includes a pull plate, an electric hoist, and an electric hoist rod. The pull plate is arranged flush with one side of the roadway scale model and is pulled outward by the electric hoist in a direction perpendicular to the side wall of the model test box to simulate the layer-by-layer mining and working face advancement process of the prototype coal seam.

[0022] Furthermore, the geological simulation similar body is made of cementitious materials and aggregates with similar theoretical proportions, and is laid in layers in the model test box.

[0023] Furthermore, the scaled-down tunnel model is designed according to the actual tunnel design dimensions and similarity theory. The scaled-down tunnel model is installed in the model test box and closely fits the geological simulation similar body.

[0024] Furthermore, the displacement acquisition system includes a fixed base, a fixed rod, and a displacement meter connected to the model experimental box. One end of the fixed rod is connected to the fixed base, and the other end is fixed inside the model experimental box. The displacement meter is fixed on the fixed rod.

[0025] The second aspect of this invention provides a test method for the test apparatus described in the first aspect for simulating the deformation law of roadways during coal seam mining, comprising the following steps:

[0026] Water bags were installed in the model test chamber, and a geological simulation similar body was laid out and a scaled-down model of the tunnel was placed inside.

[0027] Connect the excavation simulation pull-out system to the model test box;

[0028] The process of layer-by-layer coal mining was simulated using a simulated pull-out system, and the corresponding data was recorded using a displacement acquisition system.

[0029] The above one or more technical solutions have the following beneficial effects:

[0030] This invention discloses an experimental apparatus and method for simulating the deformation law of roadways during coal seam mining. The apparatus includes a model experimental box, a stratum simulation similar body, a scaled-down model of the roadway, a water-bag pressurization system, an excavation simulation pull-out system, and a displacement acquisition system. The experimental method involves installing water-bags, laying rock strata, arranging monitoring devices, applying confining pressure, and simulating mining, simultaneously acquiring roadway deformation and stress data. This invention can accurately simulate the roadway deformation process under load, reveal the stress redistribution law of the surrounding rock, and provide reliable experimental basis for support parameter optimization and stability analysis.

[0031] This invention prepares a scaled-down model of a tunnel based on the actual tunnel design dimensions and similarity theory, obtains the experimental similarity ratio, determines the size of the model's experimental chamber and the material ratio of the stratum simulation similar body based on the experimental similarity ratio, employs a layered compaction process to realize the gradient mechanical properties of the rock strata, applies uniform confining pressure through similarity theory design and a water-bag pressurization system, and simulates the dynamic excavation process through vertical backfilling. Furthermore, a displacement acquisition system and earth pressure gauges are used to monitor the tunnel's deformation and stress in real time, providing comprehensive data support for tunnel support design and stability analysis. This invention can realistically simulate the stress and deformation of a tunnel during actual mining, providing a scientific basis for tunnel support design and stability analysis.

[0032] The excavation simulation pull-out system of this invention simulates the coal seam mining process by removing plates, successfully reproducing the dynamic process of the gradual destruction of the roadway scale model during coal seam mining. It can dynamically reflect the deformation and destruction law of the roadway during gradual mining, providing a reliable test platform for quantitative analysis of failure modes and critical thresholds, and providing dynamic experimental data for studying roadway stability, thereby helping to optimize support design and improve mine safety.

[0033] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the overall structure of the similar simulation experimental device for deformation and failure of coal mine roadways in Embodiment 1 of the present invention;

[0036] Figure 2 This is a schematic diagram of the cross-sectional structure of a similar simulation experimental device for deformation and failure of coal mine roadways in Embodiment 1 of the present invention;

[0037] Figure 3 This is a schematic diagram of the overall structure of the excavation simulation pull-out system experimental frame in Embodiment 1 of the present invention;

[0038] Figure 4 This is a schematic diagram of the displacement acquisition system in Embodiment 1 of the present invention;

[0039] The components include: 1. Model test box; 2. Water pump; 3. Scale model of tunnel; 4. Fixed rod; 5. Fixed base; 6. Pulling device fixed support; 7. Electric hoist hanging rod; 8. Electric hoist; 9. Pulling plate; 10. Stratum simulation similar body; 11. Side water bladder; 12. Top water bladder; 13. Earth pressure gauge; 14. Displacement gauge. Detailed Implementation

[0040] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0043] Example 1:

[0044] Embodiment 1 of the present invention provides an experimental device for simulating the deformation law of roadways during coal seam mining, such as... Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, it includes model test chamber 1, water bladder pressurization system, excavation simulation pull-out system, and displacement acquisition system. These components form a complete system used to simulate the deformation and damage of the roadway during the mining process.

[0045] Model Experiment Box 1 is used to simulate the actual environment of the coal seam mining process. It includes a stratum simulation similar body 10 and a roadway scale model 3. The stratum simulation similar body 10 is used to reflect the mechanical properties and geological conditions of the strata, and the roadway scale model 3 is used to characterize the roadway structure.

[0046] In one specific implementation, such as Figure 1 As shown, the model test box 1 is rectangular in shape and welded from a grid of steel plates. It can withstand various forces generated during the experiment, such as confining pressure and plate pulling force, ensuring sufficient rigidity and stability. The top cover is designed to open and close, facilitating the filling of the geological simulation model and the placement of the scaled-down tunnel model and water-bag pressurization system. The top cover is connected to the box body by rivets; after closing the cover, the rivets are tightened sequentially to ensure stable water pressure in the water-bag pressurization system during the experiment.

[0047] The experimental similarity ratio of model test chamber 1 is determined based on the design dimensions of the scaled-down tunnel model 3, and the internal dimensions of the chamber are determined accordingly. To reduce the influence of rigid boundaries on the internal mechanical response of the model, sufficient surrounding rock thickness is reserved around the tunnel within the experimental chamber. The surrounding rock thickness is designed to be three times the characteristic dimension of the scaled-down tunnel model 3, that is, in the longitudinal direction of the tunnel, the rock thickness in the upper, lower, left, and right directions is three times the longest side of the scaled-down tunnel model 3. This design is determined based on the boundary effect control criterion in similar model tests. When the model boundary is more than three times the characteristic dimension of the model from the main stress area, the influence of boundary constraints on the internal stress and displacement distribution of the model can be ignored, thereby effectively reducing the interference of edge effects on the experimental results.

[0048] The volume of the model test chamber is three times the size of the scaled-down tunnel model, such as... Figure 2 As shown, the interior is equipped with a boundary transition zone and a loading reserve zone. The internal dimensions of the model test chamber 1 also include a loading reserve zone for arranging the side water bladders 11, the top water bladder 12, and the extraction plate 9. The side water bladders 11 and 12 are used to apply lateral and vertical confining pressure to the rock mass, respectively. The side water bladders 11 are positioned between the side wall of the model test chamber and the adjacent rock mass, forming lateral confining pressure loading into the rock mass. The size of the reserved space is determined comprehensively based on the effective thickness of the water bladder after inflation and the compressibility of the similar material. Specifically, based on the maximum deformation of the water bladder under loading and the compressibility of the similar material, the width of the side loading zone is reduced by 5–10 cm compared to the effective thickness of the water bladder after inflation. This ensures that the water bladder can form a stable extrusion contact after loading, allowing the confining pressure to be uniformly and continuously transmitted to the interior of the similar rock mass, avoiding local voids or stress concentration. The design principle for the reserved space of the top water bladder 12 is the same as that of the side water bladder 11, and its reserved width is also reduced by 5-10 cm compared with the effective thickness of the water bladder after inflation. After the top cover of the experimental chamber is closed, the top water bladder fits tightly against the upper surface of the rock mass, forming a downward vertical confining pressure loading, ensuring that the confining pressure is evenly distributed and effectively transferred to the main body of the model.

[0049] The installation position of the pull-out plate 9 of the excavation simulation pull-out system is set on one side of the model test box 1. The pull-out plate 9 is arranged flush with the right side wall of the roadway scale model 3, and a through hole is reserved in the side wall of the box to allow for smooth pull-out operation of the pull-out plate in the horizontal direction. This structural arrangement allows the stress change and deformation process of the roadway sidewall during the movement of the pull-out plate to be accurately reflected, thereby ensuring the continuity and realism of the mining simulation.

[0050] The model test chamber has multiple pre-drilled openings on its walls. These openings are used to install water bladder system pipelines, fix the scaled-down tunnel model, and connect components for the excavation simulation pull-out system's pull-out plates. Specifically, these include inlet holes for the water bladder pressurization system, pre-drilled holes for installing the scaled-down tunnel model, and through holes for the pull-out plates of the excavation simulation pull-out system. This ensures the installation and operation of each functional module during the experiment.

[0051] In one specific implementation, the geological simulation similar body 10 is made of cementitious materials and aggregates with similar theoretical proportions and is laid in layers in the model test box.

[0052] The formation simulation similarity body 10 is prepared based on the mechanical parameters of the prototype formation (including density, uniaxial compressive strength, elastic modulus, Poisson's ratio, etc.) obtained from in-situ core drilling tests, and after conversion using the determined geometric similarity ratio and mechanical similarity ratio. The similarity body is prepared by combining cementitious materials (cement, water, silicone oil) and aggregates (quartz sand, barite powder, talc powder) according to similarity theory. To obtain a similar material mix that meets the target mechanical parameters, an orthogonal experimental design method is used. Standard specimens are first prepared in the laboratory, cured at a specified age, and then tested for uniaxial compressive strength, static elastic modulus, and density. The results are then compared with the converted values ​​of the prototype formation parameters for calibration until a similar material formula matching the design target is determined.

[0053] To reproduce the layered mechanical characteristics of the prototype strata, the stratum simulation model 10 was prepared using a layered laying method. During layer laying, the model test box was filled layer by layer according to the stratum sequence and design mix ratio. The thickness and density of each layer were controlled by compaction to ensure tight adhesion and continuous interfaces between layers. After each layer was laid and preliminarily cured, it was cured at the specified age. After curing, in-situ testing or retesting using standard specimens was carried out to confirm that the mechanical parameters of each layer met the design requirements before proceeding to the subsequent confining pressure loading and excavation simulation tests.

[0054] In this embodiment, the formation simulation similar body 10 is made of cementitious material water, silicone oil and aggregates quartz sand, barite powder, talc powder and cement.

[0055] In one specific implementation, the tunnel scale-down model 3 is designed according to the actual tunnel design dimensions and similarity theory. The tunnel scale-down model 3 is installed in the model test box and closely fitted with the stratum simulation similar body to ensure the accuracy and reliability of the experiment.

[0056] The scaled-down tunnel model 3 in this embodiment is designed according to the tunnel prototype at a scale of 1:35 and is made of 2mm thick acrylic sheets. This ultra-thin acrylic sheet ensures structural stability while possessing excellent elasto-plastic response characteristics. It can withstand the confining pressure of surrounding similar rock masses and mining disturbances during filling and loading processes, and exhibits observable deformation under stress, thus realistically reflecting the stress and deformation patterns of the tunnel structure under actual mining conditions.

[0057] The water-filled pressurization system, installed inside the model test chamber, is used to simulate the pressurization effect during coal seam mining; it simulates the lateral and roof and floor pressures experienced by the roadway during actual mining, providing a realistic stress environment for studying the deformation and failure patterns of the roadway.

[0058] In one specific embodiment, the water bladder pressurization system is respectively installed on the top and sides of the geological simulation model 10. The inlet and outlet of the water bladder are connected to an external water pump 2 of the model experimental chamber. The water pump 2 is used to control the water pressure and ensure that the water bladder can stably apply confining pressure. A pressure sensor is installed on the connecting pipeline between the water bladder and the water pump to monitor water pressure changes in real time.

[0059] This system can apply continuous, stable, and uniform confining pressure to similar rock masses in the form of surface force, ensuring a smooth stress distribution in the model during loading and significantly reducing boundary effects. As the extraction plate 9 is gradually removed and the surrounding rock of the tunnel collapses or deforms, the water bladder deforms accordingly to fill the collapsed area. At this time, the system automatically adjusts the pump output pressure based on feedback signals from the pressure sensor, quickly restoring and maintaining uniform surface force, thereby ensuring that the collapsed area and its surrounding rock mass remain under equivalent confining pressure. This design not only improves the stability and uniformity of confining pressure loading but also dynamically reproduces the migration and redistribution of formation stress during mining simulation.

[0060] In this embodiment, the water-bag pressurization system can realistically simulate the stress environment during coal seam mining. Due to the flexible nature of the water-bag, it can provide stable and uniform confining pressure, thereby significantly reducing the boundary effect. During the gradual extraction of the sheet and the collapse or deformation of the surrounding rock in the roadway, the water-bag can also adjust its shape according to the deformation and dynamically fill the collapsed area.

[0061] Excavation simulation pull-out system is used to simulate the coal seam mining process through the movement of a pull-out plate, such as... Figure 3 As shown, it includes a pull plate 9, an electric hoist 8, and an electric hoist rod 7. The pull plate 9 is arranged flush with one side of the roadway scale model 3, and can be pulled outward by the electric hoist 8 in a direction perpendicular to the side wall of the model test box 1 to simulate the layer-by-layer mining and working face advancement process of the prototype coal seam.

[0062] In one specific implementation, the electric hoist 8 provides the driving force for pulling the pull plate 9. The target pulling speed of the electric hoist 8 is determined by converting the geometric similarity ratio and time similarity ratio of the experiment. Precise speed and displacement control is achieved through parameter setting to adapt to the simulation requirements of different mining rates and stress evolution conditions.

[0063] The excavation simulation pull-out system is set up on the right side of the tunnel scale model 3. The electric hoist 8 is connected to the pre-reserved slot of the pull plate 9 via a hook, providing the pulling power for the plate. The electric hoist 8 is suspended from the electric hoist hanging rod 7, which is installed on the pull-out device fixing support 6. The electric hoist hanging rod 7 is an adjustable horizontal support rod with sufficient rigidity to bear the weight of the electric hoist and the pulling force, and allows the electric hoist to be adjusted horizontally along the hanging rod. Before the test, the suspension position of the electric hoist on the hanging rod can be adjusted to ensure that its traction direction is perpendicular to the pulling direction of the pull plate 9, preventing deviation or tilting during the pulling process. After adjustment, the electric hoist 8 is fixed to the electric hoist hanging rod 7 using a locking device. After the pull plate 9 is inserted into the pull plate through hole of the model test box 1, its inner end is flush with the right side wall of the roadway scale model 3. After the electric hoist is started, it drives the pull plate to be smoothly pulled out in a direction perpendicular to the side wall of the model test box to simulate the step-by-step advancement process of coal seam mining.

[0064] The displacement acquisition system is used to collect deformation data of the roadway during the simulated coal seam mining process in the model test box.

[0065] In one specific implementation, such as Figure 4 As shown, the displacement acquisition system includes a fixed base 5, a fixed rod 4, an earth pressure gauge 13, and a displacement gauge 14 connected to the model test box. One end of the fixed rod 4 is connected to the fixed base 5, and the other end is fixed inside the model test box 1 and anchored to the side wall of the box. The displacement gauge 14 is fixed to the fixed rod 4 with glue. Its contacts are aligned with the middle of each wall of the tunnel scale model, forming a three-dimensional contact measurement network, which is suitable for smaller spaces. The earth pressure gauge 13 is placed against the wall before the tunnel scale model 3 is installed to ensure that it is in close contact with the model surface. This monitoring structure is flexible in layout and compact in structure, and is particularly suitable for high-precision displacement acquisition in limited spaces, which can reflect the deformation characteristics of the tunnel model in three-dimensional space in real time.

[0066] The experimental steps of the test device for simulating roadway deformation during coal seam mining in this embodiment are as follows:

[0067] (1) Install a lateral water bladder at the reserved hole on the side wall of the model experimental box, and connect its water inlet to the water pump outlet through the reserved hole to achieve lateral pressurization.

[0068] Specifically, in the model test chamber 1, the side water bag 11 is first inserted into the test chamber wall along the left side of the inlet direction of the tunnel scale model 3.

[0069] (2) Lay the stratum simulation material in layers in the model test box up to the bottom height of the tunnel entrance, place the prefabricated tunnel scale model, insert the fixing rod of the displacement acquisition system, tighten the nuts at both ends, and place the earth pressure gauge against the wall.

[0070] Specifically, the stratum simulation model 10 is laid sequentially to the lower edge of the pre-reserved opening in the tunnel scale model 3, and the tunnel scale model 3 is placed simultaneously. A displacement acquisition system is then inserted at the predetermined position. The extraction plate 9 is aligned with the right wall of the tunnel scale model 3 to ensure that it remains horizontal throughout the subsequent extraction operation. Earth pressure gauges 13 are evenly distributed on the upper, left, and lower walls of the tunnel scale model 3 to monitor the stress on each part in real time.

[0071] (3) After installing the top water bladder, seal the box and apply confining pressure to the set value through the water pump and keep the stress stable.

[0072] Specifically, after laying the ground simulating similar body 10 to the predetermined height, the top water bladder 12 is inserted and its inlet is connected to the outlet of the water pump 2 to complete the installation of the top cover of the model experiment box 1. The cover is then tightened with rivets to ensure the water pressure of the water bladder pressurization system is stable during the experiment.

[0073] (4) Insert the plate into the reserved plate slot so that the top of the plate is aligned with the right side of the roadway.

[0074] (5) Continue to lay the stratum simulation material to the predetermined position to prevent the top water bladder from shifting. Then connect the water inlet of the top water bladder to the water pump outlet through the reserved hole, and then cover it with the top cover plate.

[0075] (6) Connect one end of the electric hoist to the pre-reserved slot of the pull plate, and the other end to the electric hoist hanging rod. Based on the principle of similarity and the time similarity ratio, establish a scaling formula for the pulling speed:

[0076] .

[0077] In the formula: "day" represents the prototype mining speed. It is a geometric scale; To obtain the extraction speed using time similarity ratio, the electric hoist was operated according to the extraction speed to sequentially extract the extraction plates along the hoist's hanging rod, simulating the coal seam mining process. The deformation and damage of the roadway during the mining process were observed and recorded in real time. The data was analyzed to quantify the critical threshold for roadway damage and the evolution pattern of deformation.

[0078] Specifically, after the internal stress of the simulated geological structure 10 stabilizes, the water pump 2 is started and adjusted to the set pressure to ensure that the internal pressure of the water bladder is stable and meets the loading requirements. At this time, the water bladder pressurization system simultaneously applies loads to the upper part and sides of the model to simulate the confining pressure experienced by a roadway in an actual mine. Next, ensuring that the direction of the electric hoist 8 pulling the plates is perpendicular to the right wall of the model test box 1, the time and speed of the plate pulling operation are determined according to the similarity principle, and all plates 9 are gradually and slowly pulled out to simulate the gradual destruction process of the roadway structure during coal seam mining. Throughout the plate pulling mining process, relying on the pre-arranged displacement acquisition system and earth pressure gauge 13, the deformation and stress changes of the roadway scale model 3 during the plate pulling operation and on each side (upper, lower, left, right and bottom) are recorded in real time. Through the dynamic data obtained by continuous monitoring, the evolution process of roadway structure destruction is analyzed in detail.

[0079] During the confining pressure loading phase, the system automatically adjusts the water pump output based on real-time feedback from pressure sensors. This ensures that the expansion or contraction of the water bladder precisely matches the local deformation of the rock mass, thereby quickly filling collapses or voids. This method maintains uniform surface force, avoids boundary effects, and ensures continuous and stable surrounding rock pressure, providing reliable support for subsequent extraction operations.

[0080] Example 2:

[0081] Embodiment 2 of the present invention provides a test method for the test device for simulating the roadway deformation law during coal seam mining as described in the first aspect, comprising the following steps:

[0082] Step 1: Install water bladders, lay out geological strata simulation similarities, and place scaled-down tunnel models inside the model test chamber.

[0083] Step 2: Connect the excavation simulation pull-out system to the model test box.

[0084] Step 3: Use a simulated pulling system to simulate the layer-by-layer mining process in a coal mine, and use a displacement acquisition system to record the corresponding data.

[0085] The steps involved in the above embodiment two correspond to those in embodiment one. For specific implementation details, please refer to the relevant description section of embodiment one.

[0086] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A test device for simulating roadway deformation law in coal seam mining process, characterized in that, The utility model relates to a model experiment box for simulating the actual environment of coal seam mining process, which comprises a stratum simulation similar body and a roadway scale model. The utility model relates to a water bag pressurization system arranged in the model experiment box for simulating the pressurization effect in the coal seam mining process, which comprises a top water bag and a side water bag. The model experiment box has a volume three times the size of the roadway scale model and is internally provided with a boundary transition zone and a loading reserved zone. The utility model relates to an excavation simulation pulling system for simulating the coal seam mining process by pulling out a plate. The utility model relates to a displacement acquisition system for acquiring the deformation data of the roadway in the model experiment box during the simulation of the coal seam mining process. The model experiment box is a cuboid shape and is welded by a cross-shaped steel plate.

2. The test device for simulating the deformation law of a roadway in a coal seam mining process according to claim 1, characterized in that, The model experiment box is provided with a plurality of openings on the wall, including water inlet holes for the water bag pressurization system, reserved openings for installing the roadway scale model, and plate through holes for the excavation simulation pulling system.

3. The test device for simulating the deformation law of a roadway in a coal seam mining process according to claim 1, characterized in that, The loading reserved zone is used for arranging the side water bag, the top water bag and the plate.

4. The test device for simulating the deformation law of a roadway in a coal seam mining process according to claim 1, characterized in that, The stratum simulation similar body is made of a similar theoretical proportion of cementing material and aggregate and is layered in the model experiment box.

5. The test device for simulating the deformation law of a roadway in a coal seam mining process according to claim 1, characterized in that, The roadway scale model is designed according to the actual roadway size and the similarity theory.

6. The test device for simulating the deformation law of a roadway in a coal seam mining process according to claim 1, characterized in that, The displacement acquisition system comprises a fixed base connected with the model experiment box, a fixed rod and a displacement meter.

7. The test device for simulating the deformation law of a roadway in a coal seam mining process according to claim 1, characterized in that, The utility model comprises the following steps:

8. A test method for the test device for simulating the deformation law of a roadway in a coal seam mining process according to any one of claims 1-7, characterized in that, installing the water bag in the model experiment box, laying the stratum simulation similar body and placing the roadway scale model; connecting the excavation simulation pulling system with the model experiment box; simulating the layer-by-layer mining process of the coal mine by using the simulation pulling system and recording the corresponding data by using the displacement acquisition system. ​

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