Coal seam mining model test device and test method

Abstract

The invention discloses a coal mining model test device and test method, and relates to the field of mining engineering tests, the coal mining model test device comprises a side beam, the top end of the side beam is provided with a top beam, the bottom end of the side beam is provided with a base, and the inner side of the side beam is provided with a hydraulic system. Through the arrangement of the first positioning seats, the second positioning seats, the mounting seats and the threaded rods, the mounting seats on the outer sides of the jacks with the corresponding number are connected in a pairwise clamping mode through the clamping blocks and the clamping grooves, the first positioning seats are clamped and fixed to the mounting seat at the topmost end, and the second positioning seats are clamped and fixed to the mounting seat at the bottommost end; the first positioning seats, the mounting seats and the second positioning seats are connected together, then the first positioning seats, the mounting seats and the second positioning seats are inserted into the inner sides of the side beams and fixedly mounted on the side beams through threaded rods, the jacks are fixedly mounted on the side beams, and according to the same method, the other three sets of first positioning seats, mounting seats and second positioning seats are fixedly mounted on the other side beam, the top beam and the base. And the jack is installed.

Description

Technical Field

[0001] The present invention relates to the technical field of mining engineering, and particularly to a coal seam mining model test device and a test method. Background Technique

[0002] When the thickness of the coal seam is moderate and it can be mined in one go by a certain method, it is called full-seam mining. When the coal seam is too thick, it is divided into several layers and mined in sequence from top to bottom or from bottom to top, which is called slicing mining. Currently, most of the test devices for the surface subsidence model of coal seam mining require manual operation for coal seam mining or gob site construction. Although it can meet the requirements of model tests to a certain extent, in the test process, over-mining or under-mining often occurs, which affects the test accuracy and data accuracy. In addition, the workload of manually mining the coal seam in the indoor model is large, greatly increasing the labor intensity, time cost and test difficulty, and at the same time reducing the test success rate.

[0003] In view of the above problems, although a coal seam mining model test device has been developed, such as the utility model patent with the publication number CN 204405654 U, a device for simulating gob mining. This device inserts a hollow tube into a rubber tube filled with sand to simulate gob mining by discharging sand. The rubber tube of this device is filled with sand and laid horizontally. Under the self-weight of the overlying soil layer, the sand is compressed and compacted with poor fluidity, making it difficult to operate and resulting in poor test results. This device can only simulate shallow gob areas and cannot simulate the influence of high-speed rail cyclic dynamic loads on the gob foundation, resulting in poor test results for the coal seam mining model test. The driving equipment installation on the test model is complex, the labor intensity of the test personnel is high, and the template is fixed by bolts with a long installation time. Therefore, there is an urgent need for a coal seam mining model test device and a test method. Summary of the Invention

[0004] The purpose of the present invention is to provide a coal seam mining model test device and a test method to solve the problems of poor test results of the existing coal seam mining model test, complex installation of the driving equipment on the test model, high labor intensity of the test personnel, and long installation time for the template fixed by bolts.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A coal seam mining model test device and a test method, including side beams, a top beam is provided at the top end of the side beams, and a base is provided at the bottom end of the side beams. A hydraulic system is provided inside the side beams, and a clamping structure is provided on the outer wall of the side beams.

[0006] The hydraulic system includes a first positioning seat. A clamping block is provided at the bottom end of the first positioning seat, and a threaded rod is movably arranged at the top end of the first positioning seat. A jack is installed inside the first positioning seat, and a mounting seat is clamped below the first positioning seat. A clamping groove is formed at the top end of the mounting seat, and a second positioning seat is arranged below the mounting seat. A steel plate is provided at the output end of the jack, and a plug is connected to the bottom end of the second positioning seat.

[0007] The clamping structure includes a spring. An L-shaped frame is connected to the end of the spring. A template is clamped on the outside of the L-shaped frame. A limiting groove is formed on the template, and a connecting block is fixed to the bottom end of the template. A connecting groove is formed at the top end of the template, and a handle is arranged on the outer wall of the template.

[0008] Preferably, a support seat is fixed to the bottom end of the base. Limiting blocks matching the first positioning seat and the second positioning seat are arranged inside the side beam, the top beam, and the base. The number of the first positioning seats, the mounting seats, and the second positioning seats is four groups. The four groups of the first positioning seats, the mounting seats, and the second positioning seats are respectively clamped and installed with the side beam, the top beam, and the base. The number of the side beams is two, and a filling groove is formed inside the two side beams.

[0009] Preferably, a threaded groove matching the threaded rod is formed at the top of the first positioning seat, and the threaded rod is movably connected to the top beam and the base through threads. Clamping grooves are formed at the top ends of the mounting seat and the second positioning seat, and clamping blocks are fixed to the bottom ends of the mounting seat and the first positioning seat.

[0010] Preferably, slots matching the plugs are formed on both sides of the base. The mounting seat is clamped and connected to the first positioning seat and the second positioning seat through the clamping blocks and the clamping grooves. The first positioning seat is movably connected to the top beam through the threaded rod and the threaded groove. The second positioning seat is clamped and connected to the base through the plug and the slot.

[0011] Preferably, a contraction groove matching the spring is formed on the surface of the side beam, and the L-shaped frame is movably connected to the side beam through the spring. The limiting groove is clamped and connected to the L-shaped frame.

[0012] Preferably, the number of the templates is multiple. The multiple templates are clamped and connected through the connecting blocks and the connecting grooves, and the templates are clamped and fixed to the side beam through the L-shaped frames and the limiting grooves.

[0013] A method for model test of coal seam mining includes the following steps: Step 1: Preparation work before the test. Determine the height of the test model, the coal seam cutting roadway, and the advancing distance, and then determine the number of mounting seats in the model device to be called during the test. Step 2: Laying the test model. After completing the preparatory work in Step 1, configure the similar materials required for the test, and fill the similar materials into the filling tank for layered laying and compaction. Mica flakes are sprinkled between soil layers. At the same time, various sensors such as earth pressure cells, vibration accelerometers, and strain gauges are accurately installed and positioned at the corresponding positions in the model. After the model laying is completed, the hydraulic systems of the left and right side beams and the top beam can be used to preload the similar materials in the filling tank to achieve the pressure and strength of simulating the actual geological environment; Step 3: Demolish the formwork. After the similar model laying is completed, let it stand for 2 - 3 days, and the time can be adjusted according to the temperature, appropriately extended in winter and shortened in summer. After standing, the formwork can be successively demolished symmetrically from top to bottom and front to back. After the formwork is demolished, continue to air-dry the model for a period of time. After the similar model reaches the test strength, the subsequent coal seam mining work can be carried out; Step 4: Connect and debug the sensors. Connect the various sensors embedded in the model to the corresponding information acquisition instruments, and set the corresponding parameters of various sensors in the acquisition system to improve the accuracy and acquisition efficiency of test data acquisition; Step 5: Coal seam excavation and dynamic monitoring. The first positioning seat, installation seat, and second positioning seat required to be called in the base determined in Step 1, by controlling the steel plates at the output ends of the first positioning seat, installation seat, and second positioning seat inside the intelligent control base to descend at a certain rate to simulate the coal seam mining process. During the coal seam mining process, transmit the test data collected by various sensors to the computer, and use software to process and analyze the data. At the same time, an external high-speed camera device can be used to record the deformation and evolution process of the overlying strata in the goaf.

[0014] Preferably, in Step 5, when carrying out coal seam excavation, the descending speed of the steel plates at the output ends of the first positioning seat, installation seat, and second positioning seat inside the base should not exceed 5 mm / min to avoid triggering the dynamic effect of the overlying strata in the goaf during the coal seam mining process. And when controlling the steel plates at the output ends of the first positioning seat, installation seat, and second positioning seat inside the base, the final descending displacement of the steel plates should be consistent, and at the same time, the descending displacement of the steel plates should be the same as the coal seam thickness in the model test.

[0015] Preferably, the hydraulic system inside the side beam can provide the lateral pressure in the rock and soil layer, and the hydraulic system inside the top beam can provide the upper load of the rock and soil layer.

[0016] Compared with the prior art, the beneficial effects of the present invention are: First, the present invention is provided with a first positioning seat, a second positioning seat, a mounting seat, and a threaded rod. The mounting seats on the outer sides of a corresponding number of jacks are connected in pairs by engaging blocks and engaging grooves. The first positioning seat is fixedly engaged with the topmost mounting seat, and the second positioning seat is fixedly engaged with the lowermost mounting seat. Then, the first positioning seat, the mounting seat, and the second positioning seat are connected together, and then inserted into the inner side of the side beam and fixedly installed on the side beam through the threaded rod. Thus, a plurality of jacks are fixedly installed on the side beam. According to the same method, the other three groups of the first positioning seat, the mounting seat, and the second positioning seat are fixedly installed on another side beam, the top beam, and the base, and then the installation of the jacks is completed.

[0017] Second, the present invention is provided with a template, an L-shaped frame, a spring, and a limiting groove. Before laying the test model, according to the height of the coal seam, the number of templates is determined. The templates are placed at the front end of the side beam. The limiting grooves on the templates first pass through the L-shaped frame and then press down on the templates. After the templates are stressed, the limiting grooves on their inner sides squeeze the L-shaped frame. During the squeezing process, the springs at the ends of the L-shaped frame are continuously displaced outward until the templates are completely inserted into the inner sides of the L-shaped frames. At this time, the templates are fixedly engaged with the L-shaped frames through the limiting grooves, and the L-shaped frames are tightly attached to the templates under the driving force of the elastic force of the springs, thereby fixing the templates to the side beam. When installing other templates, after the other templates are engaged and moved down on the L-shaped frames, the connecting blocks at their bottoms are inserted into the connecting grooves at the tops of the lower templates, so that the two templates are engaged and connected, and thus multiple templates can be connected and fixed at the front and rear ends of the side beam.

[0018] Third, the present invention simulates coal seam excavation through the hydraulic system in the base, which can not only effectively realize coal seam mining, rock stratum deformation monitoring, and the construction of goaf sites, but also more efficiently conduct coal seam mining model tests, greatly reducing the labor intensity of test personnel, thereby reducing the difficulty of model tests and improving test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of the overall structure of the present invention; Figure 2 is a schematic diagram of the front sectional structure of the present invention; Figure 3 is a schematic diagram of the hydraulic system structure of the present invention; Figure 4 is of the present invention Figure 3 an enlarged schematic diagram of A in; Figure 5 is a schematic diagram of the second positioning seat of the present invention; Figure 6 is a schematic diagram of the front view structure of the present invention; Figure 7 is a schematic diagram of the engaging structure of the present invention; Figure 8 is of the present inventionFigure 7 Enlarged schematic diagram of B in it; Figure 9 Schematic flow diagram of the test method of the present invention.

[0020] In the figure: 1, side beam; 2, top beam; 3, base; 4, support seat; 5, hydraulic system; 501, first positioning seat; 502, engaging block; 503, engaging groove; 504, jack; 505, steel plate; 506, mounting seat; 507, second positioning seat; 508, inserting block; 509, threaded rod; 6, limiting block; 7, engaging structure; 701, spring; 702, L-shaped frame; 703, template; 704, limiting groove; 705, connecting block; 706, connecting groove; 707, handle. Specific embodiments

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Please refer to Figures 1 - 4, a coal seam mining model test device and test method, including side beams 1, with a top beam 2 provided at the top of the side beams 1, and a base 3 provided at the bottom of the side beams 1. A hydraulic system 5 is provided inside the side beams 1, and a clamping structure 7 is provided on the outer wall of the side beams 1. The hydraulic system 5 includes a first positioning seat 501, with a clamping block 502 provided at the bottom of the first positioning seat 501, and a threaded rod 509 is movably provided at the top of the first positioning seat 501. A jack 504 is installed inside the first positioning seat 501, and a mounting seat 506 is clamped below the first positioning seat 501. A clamping groove 503 is opened at the top of the mounting seat 506, and a second positioning seat 507 is provided below the mounting seat 506. The output end of the jack 504 is provided with a steel plate 505, and a plug 508 is connected to the bottom of the second positioning seat 507. A support seat 4 is fixed to the bottom of the base 3. Limit blocks 6 matching the first positioning seat 501 and the second positioning seat 507 are provided inside the side beams 1, the top beam 2, and the base 3. The number of the first positioning seats 501, the mounting seats 506, and the second positioning seats 507 is four groups. The four groups of the first positioning seats 501, the mounting seats 506, and the second positioning seats 507 are respectively clamped and installed with the side beams 1, the top beam 2, and the base 3. The number of the side beams 1 is two, and the inside of the two side beams 1 is a filling groove. A threaded groove matching the threaded rod 509 is opened at the top of the first positioning seat 501, and the threaded rod 509 is movably connected to the top beam 2 and the base 3 through threads. Clamping grooves 503 are opened at the tops of the mounting seat 506 and the second positioning seat 507, and clamping blocks 502 are fixed to the bottoms of the mounting seat 506 and the first positioning seat 501. Slots matching the plug 508 are opened on both sides of the base 3. The mounting seat 506 is clamped and connected to the first positioning seat 501 and the second positioning seat 507 through the clamping blocks 502 and the clamping grooves 503. The first positioning seat 501 is movably connected to the top beam 2 through the threaded rod 509 and the threaded groove. The second positioning seat 507 is clamped and connected to the base 3 through the plug 508 and the slots. According to the height of the coal seam, determine the required size of the test device. According to the height of the side beam 1 and the lengths of the top beam 2 and the base 3, further determine the number of the jacks 504. Clamp and connect the mounting seats 506 outside the corresponding number of multiple jacks 504 in pairs through the clamping blocks 502 and the clamping grooves 503, so that the multiple jacks 504 are fixedly connected through the mounting seats 506. Then clamp and fix the first positioning seat 501 and the topmost mounting seat 506 through the clamping blocks 502 and the clamping grooves 503. Clamp and fix the second positioning seat 507 and the bottommost mounting seat 506 through the clamping blocks 502 and the clamping grooves 503. Then the first positioning seat 501, the mounting seat 506, and the second positioning seat 507 are connected together, and then insert them into the inside of the side beam 1, and insert the plug 508 at the bottom of the second positioning seat 507 into the slot at the top of the base 3. At this time, rotate the threaded rod 509, and the threaded rod 509 rotates inside the top beam 2, and thus screws into the threaded groove at the top of the first positioning seat 501.Then the first positioning seat 501 is fixedly installed with the side beam 1, so that the mounting seat 506 and the second positioning seat 507 are fixedly installed with the side beam 1. Then, multiple jacks 504 are fixedly installed with the side beam 1. According to the same method, the other three groups of the first positioning seat 501, the mounting seat 506, and the second positioning seat 507 are fixedly installed with the other side beam 1, the top beam 2, and the base 3. Then the installation of the jacks 504 is completed.

[0023] Please refer to Figures 5 - 8 A coal seam mining model test device and test method. The clamping structure 7 includes a spring 701. The end of the spring 701 is connected with an L-shaped frame 702. The outside of the L-shaped frame 702 is clamped with a template 703. A limiting groove 704 is opened on the template 703. A connecting block 705 is fixed at the bottom end of the template 703. A connecting groove 706 is opened at the top end of the template 703. A handle 707 is arranged on the outer wall of the template 703. A contraction groove matching with the spring 701 is opened on the surface of the side beam 1. The L-shaped frame 702 is movably connected with the side beam 1 through the spring 701. The limiting groove 704 is clamped and connected with the L-shaped frame 702. The number of templates 703 is multiple. Multiple templates 703 are clamped and connected through the connecting block 705 and the connecting groove 706. The template 703 and the side beam 1 are clamped and fixed through the L-shaped frame 702 and the limiting groove 704. Before laying the test model, according to the height of the coal seam, the number of templates 703 is determined. The template 703 is placed at the front end of the side beam 1. The limiting groove 704 on the template 703 first passes through the L-shaped frame 702, and then the template 703 is pressed downward. After the template 703 is stressed, the limiting groove 704 inside it presses the L-shaped frame 702. During the pressing process, the L-shaped frame 702 stretches the spring 701 at the end and moves outward continuously until the template 703 is completely inserted into the inside of the L-shaped frame 702. At this time, the template 703 is clamped and fixed with the L-shaped frame 702 through the limiting groove 704. And the L-shaped frame 702 is tightly attached to the template 703 under the driving force of the elastic force of the spring 701, so that the template 703 is fixed with the side beam 1. When installing other templates 703, after other templates 703 are clamped and moved down on the L-shaped frame 702, the connecting block 705 at the bottom end is inserted into the connecting groove 706 at the top of the lower template 703, so that two adjacent templates 703 are clamped and connected. Thus, after multiple templates 703 are connected, they can be fixed at the front and rear ends of the side beam 1.

[0024] Please refer to Figure 9 A coal seam mining model test method includes the following steps: Step 1: Preparation work before the test. Determine the height of the test model, the coal seam cutting roadway and the advancing distance, and then determine the number of jacks 504 required to be called in during the test in the model device. Step 2: Laying the test model. After completing the preparations in Step 1, configure the similar materials required for the test, and fill the similar materials into the filling tank for layered laying and compaction. Mica sheets are scattered between soil layers. At the same time, various sensors such as earth pressure cells, vibration accelerometers, and strain gauges are precisely installed and positioned at the corresponding positions in the model. After the model laying is completed, the hydraulic system 5 of the left and right side beams 1 and the top beam 2 can be used to preload the similar materials in the filling tank to achieve the pressure and strength for simulating the actual geological environment; Step 3: Dismantling the formwork 703. After the similar model laying is completed, let it stand for 2 - 3 days. The time can be adjusted according to the temperature, appropriately extended in winter and shortened in summer. After standing, the formwork 703 can be successively dismantled from top to bottom and symmetrically from front to back. After the formwork 703 is dismantled, continue to air-dry the model for a period of time. After the similar model reaches the test strength, the subsequent coal seam mining work can be carried out; Step 4: Connecting and debugging the sensors. Connect the various sensors embedded in the model to the corresponding information acquisition instruments, and set the corresponding parameters of the various sensors in the acquisition system to improve the accuracy and acquisition efficiency of test data acquisition; Step 5: Coal seam excavation and dynamic monitoring. The first positioning seat 501, mounting seat 506, and second positioning seat 507 required to be called in the base determined in Step 1. The steel plate 505 at the output ends of the first positioning seat 501, mounting seat 506, and second positioning seat 507 inside the intelligent control base 3 descends at a certain rate to simulate the coal seam mining process. During the coal seam mining process, the test data collected by various sensors is transmitted to the computer, and the software is used to process and analyze the data. At the same time, an external high-speed camera device can be used to record the deformation and evolution process of the overlying strata in the goaf; In Step 5, when carrying out coal seam excavation, the descending speed of the steel plate 505 at the output ends of the first positioning seat 501, mounting seat 506, and second positioning seat 507 inside the base 3 should not exceed 5 mm / min to avoid triggering the dynamic effect of the overlying strata in the goaf during the coal seam mining process. When controlling the steel plate 505 at the output ends of the first positioning seat 501, mounting seat 506, and second positioning seat 507 inside the base 3, the final descending displacement of the steel plate 505 should be kept consistent. At the same time, the descending displacement of the steel plate 505 should be the same as the coal seam thickness in the model test. The hydraulic system 5 inside the side beam 1 can provide the lateral pressure in the rock and soil layers, and the hydraulic system 5 inside the top beam 2 can provide the upper load of the rock and soil layers.

[0025] Working principle: When the present invention is in use, first perform Step 1: Preparation work before the test. Determine the height of the test model, the starting cut of the coal seam, and the advancing distance, and then determine the number of jacks 504 in the model device to be called during the test. According to the height of the coal seam, determine the size required for the test device. According to the height of the side beam 1 and the lengths of the top beam 2 and the base 3, further determine the number of jacks 504. Connect the mounting seats 506 outside the corresponding number of multiple jacks 504 in pairs through the engaging blocks 502 and the engaging grooves 503. Then, fix the first positioning seat 501 and the topmost mounting seat 506 through the engaging blocks 502 and the engaging grooves 503, and fix the second positioning seat 507 and the lowermost mounting seat 506 through the engaging blocks 502 and the engaging grooves 503. Then, the first positioning seat 501, the mounting seats 506, and the second positioning seat 507 are connected together, and then inserted into the inside of the side beam 1. And the insertion block 508 at the bottom end of the second positioning seat 507 is inserted into the slot on the top of the base 3. At this time, rotate the threaded rod 509. The threaded rod 509 rotates inside the top beam 2 and thus screws into the threaded groove at the top end of the first positioning seat 501. Then, the first positioning seat 501 is fixedly installed with the side beam 1, and further the mounting seats 506 and the second positioning seat 507 are fixedly installed with the side beam 1. Then, the multiple jacks 504 are fixedly installed with the side beam 1. According to the same method, fix the other three groups of the first positioning seat 501, the mounting seats 506, and the second positioning seat 507 with another side beam 1, top beam 2, and base 3. Then, the installation of the jacks 504 is completed. Before laying the test model, according to the height of the coal seam, determine the number of templates 703. Place the templates 703 at the front end of the side beam 1. The limiting grooves 704 on the templates 703 first pass through the L-shaped frames 702, and then press down the templates 703. After the templates 703 are stressed, the limiting grooves 704 inside them press on the L-shaped frames 702. During the pressing process, the springs 701 at the stretching ends of the L-shaped frames 702 continuously move outwards until the templates 703 are completely inserted into the inside of the L-shaped frames 702. At this time, the templates 703 are fixedly engaged with the L-shaped frames 702 through the limiting grooves 704, and the L-shaped frames 702 are tightly attached to the templates 703 under the elastic force of the springs 701. Thus, the templates 703 are fixed to the side beam 1. And when installing other templates 703, after the other templates 703 are engaged and moved down on the L-shaped frames 702, the connecting blocks 705 at their bottom ends are inserted into the connecting grooves 706 at the top of the lower templates 703. Then, the two templates 703 are engaged and connected. Thus, after connecting multiple templates 703, they can be fixed at the front and rear ends of the side beam 1. Then, perform Step 2: Laying the test model. After completing the preparation work in Step 1, configure the similar materials required for the test, and fill the similar materials into the filling grooves for layered laying and compaction. Mica flakes are scattered between the soil layers. At the same time, accurately install and position various sensors, such as earth pressure cells, vibration accelerometers, and strain gauges, at the corresponding positions in the model. After the model laying is completed,The hydraulic system 5 of the left and right side beams 1 and the top beam 2 can be used to preload and load the similar materials in the filling tank to achieve the pressure and strength of simulating the actual geological environment; Step 3: Demolish the formwork 703. After the similar model is laid, let it stand for 2 to 3 days. The time can be adjusted according to the temperature, appropriately extended in winter and appropriately shortened in summer. After standing, the formwork 703 can be successively demolished symmetrically from top to bottom and front and back. After the formwork 703 is demolished, continue to air-dry the model for a period of time. After the similar model reaches the test strength, the subsequent coal seam mining work can be carried out; Step 4: Connect and debug the sensors. Connect the various sensors embedded in the model to the corresponding information acquisition instruments, and set the corresponding parameters of the various sensors in the acquisition system to improve the accuracy and acquisition efficiency of the test data acquisition; Step 5: Coal seam excavation and dynamic monitoring. The first positioning seat 501, the mounting seat 506 and the second positioning seat 507 required to be called in the base determined in Step 1. The steel plate 505 at the output ends of the first positioning seat 501, the mounting seat 506 and the second positioning seat 507 inside the intelligent control base 3 descends at a certain rate to simulate the coal seam mining process. During the coal seam mining process, transmit the test data collected by the various sensors to the computer, and use software to process and analyze the data. At the same time, the deformation and evolution process of the overlying strata in the goaf can be recorded by using external high-speed camera equipment and instruments, so that the coal seam mining model test is completed.

[0026] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention.

Claims

1. A model test device for coal seam mining, including side beams (1), characterized in that: A top beam (2) is provided at the top end of the side beam (1), and a base (3) is provided at the bottom end of the side beam (1). A hydraulic system (5) is provided inside the side beam (1), and a clamping structure (7) is provided on the outer wall of the side beam (1); The hydraulic system (5) includes a first positioning seat (501). A clamping block (502) is provided at the bottom end of the first positioning seat (501), and a threaded rod (509) is movably provided at the top end of the first positioning seat (501). A jack (504) is installed inside the first positioning seat (501), and a mounting seat (506) is clamped below the first positioning seat (501). A clamping groove (503) is formed at the top end of the mounting seat (506), and a second positioning seat (507) is provided below the mounting seat (506). A steel plate (505) is provided at the output end of the jack (504), and a plug (508) is connected to the bottom end of the second positioning seat (507); The clamping structure (7) includes a spring (701). An L-shaped frame (702) is connected to the end of the spring (701). A template (703) is clamped outside the L-shaped frame (702). A limiting groove (704) is formed on the template (703), and a connecting block (705) is fixed to the bottom end of the template (703). A connecting groove (706) is formed at the top end of the template (703), and a handle (707) is provided on the outer wall of the template (703).

2. The coal seam mining model test device according to claim 1, characterized in that: A support seat (4) is fixed to the bottom end of the base (3). Limiting blocks (6) matching the first positioning seat (501) and the second positioning seat (507) are provided inside the side beam (1), the top beam (2), and the base (3). The number of the first positioning seats (501), the mounting seats (506), and the second positioning seats (507) is four groups. The four groups of the first positioning seats (501), the mounting seats (506), and the second positioning seats (507) are respectively clamped and installed with the side beam (1), the top beam (2), and the base (3). The number of the side beams (1) is two, and the inside of the two side beams (1) is a filling groove.

3. The coal seam mining model test device according to claim 1, wherein: A threaded groove matching the threaded rod (509) is formed at the top of the first positioning seat (501), and the threaded rod (509) is movably connected to the top beam (2) and the base (3) through threads. Clamping grooves (503) are formed at the top ends of the mounting seat (506) and the second positioning seat (507), and clamping blocks (502) are fixed to the bottom ends of the mounting seat (506) and the first positioning seat (501).

4. A coal seam mining model test device according to claim 1, characterized in that: Slots matching the plug (508) are formed on both sides of the base (3). The mounting seat (506) is clamped and connected to the first positioning seat (501) and the second positioning seat (507) through the clamping blocks (502) and the clamping grooves (503). The first positioning seat (501) is movably connected to the top beam (2) through the threaded rod (509) and the threaded groove. The second positioning seat (507) is clamped and connected to the base (3) through the plug (508) and the slots.

5. A coal seam mining model test device according to claim 1, characterized in that: The surface of the side beam (1) is provided with a shrinkage groove matching the spring (701), and the L-shaped frame (702) is movably connected to the side beam (1) through the spring (701), and the limiting groove (704) is engaged with the L-shaped frame (702).

6. The model test device for coal seam mining according to claim 1, wherein: The number of the templates (703) is multiple, and the multiple templates (703) are engaged and connected through the connecting blocks (705) and the connecting grooves (706), and the templates (703) are fixedly engaged with the side beam (1) through the L-shaped frame (702) and the limiting groove (704).

7. A method for a coal seam mining model test, applied to a coal seam mining model test device according to any one of claims 1 to 6, comprising the following steps: Step 1: Preparation work before the test, determining the height of the test model, the coal seam cutting roadway and the advancing distance, and further determining the number of the mounting seats (506) in the model device to be called during the test process; Step 2: Laying of the test model. After completing the preparation work in Step 1, preparing the similar materials required for the test, filling the similar materials into the filling groove for layered laying and compaction, sprinkling mica flakes between the soil layers, and at the same time precisely installing and positioning various sensors such as soil pressure cells, vibration accelerometers, and strain gauges at the corresponding positions in the model. After the model is laid, the hydraulic system (5) of the left and right side beams (1) and the top beam (2) can be used to preload the similar materials in the filling groove to achieve the pressure and strength simulating the actual geological environment; Step 3: Dismantling the templates (703). After the similar model is laid, it is left to stand for 2 to 3 days, and the time can be adjusted according to the temperature, appropriately extended in winter and appropriately shortened in summer. After standing, the templates (703) can be successively dismantled symmetrically from top to bottom and front to back. After the templates (703) are dismantled, the model is left to dry for a while. After the similar model reaches the test strength, the subsequent coal seam mining work can be carried out; Step 4: Connecting and debugging the sensors. Connecting the various sensors embedded in the model to the corresponding information acquisition instruments, and setting the corresponding parameters of the various sensors in the acquisition system to improve the accuracy and acquisition efficiency of the test data acquisition; Step 5: Coal seam excavation and dynamic monitoring. The first positioning seat (501), the mounting seat (506) and the second positioning seat (507) to be called in the base determined in Step 1, through the steel plates (505) at the output ends of the first positioning seat (501), the mounting seat (506) and the second positioning seat (507) inside the intelligent control base (3), descend at a certain rate to simulate the coal seam mining process. During the coal seam mining process, transmitting the test data collected by the various sensors to a computer, and using software to process and analyze the data. At the same time, the deformation and evolution process of the overlying strata in the goaf can be recorded by using an external high-speed camera device instrument.

8. A method for model test of coal seam mining according to claim 7, characterized in that: In the fifth step, when coal seam excavation is carried out, the downward speed of the steel plate (505) at the output ends of the first positioning seat (501), the mounting seat (506), and the second positioning seat (507) inside the base (3) should not exceed 5 mm / min to avoid triggering the dynamic effect of overlying strata in the goaf during coal seam mining. Moreover, when controlling the steel plate (505) at the output ends of the first positioning seat (501), the mounting seat (506), and the second positioning seat (507) inside the base (3), the final downward displacement of the steel plate (505) should be kept consistent, and at the same time, the downward displacement of the steel plate (505) should be the same as the coal seam thickness in the model test.

9. A method for model test of coal seam mining according to claim 7, characterized in that: The hydraulic system (5) inside the side beam (1) can provide the lateral pressure in the rock and soil layer, and the hydraulic system (5) inside the top beam (2) can provide the load on the upper part of the rock and soil layer.

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