Physical simulation device for coal mine working face end suspended roof form

Abstract

The utility model belongs to the technical field of coal mining and roof control, and provides a coal mine working face end suspended roof form physical simulation device which comprises a box body, a batten layer, a similar material layer, a load piece and a shooting device, and a notch is formed in the bottom of one side wall of the box body; the batten layer comprises a plurality of battens, the battens are sequentially laid at the bottom of the box body in the length direction, and one ends of the battens extend out of the notches; the material similar layer is located on the battens in the box body, and the material similar layer sequentially comprises lower-layer siltstone, fine-grained sandstone, mudstone and upper-layer siltstone from bottom to top; the load piece is positioned above the similar material layer; the shooting device is located on the outer side of the side wall, provided with the notch, of the box body and used for shooting the caving degree of the similar material layer. According to the utility model, the problems of large error, high cost and insufficient precision of the traditional monitoring means can be solved, the suspended roof form and the caving rule can be accurately restored through three-dimensional physical simulation, and a scientific basis is provided for safe treatment of the suspended roof.

Description

TECHNICAL FIELD

[0001] The utility model belongs to coal mining and roof control technical field, provide a kind of coal face end head overhanging roof shape physical simulation device. BACKGROUND

[0002] In the mining process of shallow buried large mining height working face, end head overhanging roof is the main inducement of insufficient roof caving, stress concentration and rock burst, directly affects the safety of coal mining.

[0003] Traditional overhanging roof monitoring relies on artificial experience estimation, and the error is large and the risk is high;Although field drilling observation is intuitive, it is high in cost and difficult to implement, and it is difficult to realize dynamic monitoring;Numerical simulation is affected by boundary condition simplification, and the precision is insufficient, and the three-dimensional dynamic caving process of overhanging roof cannot be accurately restored.

[0004] The prior art lacks simulation means capable of systematically revealing the spatial form, cross-layer distribution rule and dynamic caving characteristics of overhanging roof, resulting in lack of scientific basis for overhanging roof treatment time and layer selection, and there are problems of ineffective treatment or delayed treatment. UTILITY MODEL CONTENTS

[0005] In order to solve the above technical problems, the utility model provides a kind of coal face end head overhanging roof shape physical simulation device, which can solve the problems of large error, high cost and insufficient precision of traditional monitoring means, accurately restore the overhanging roof shape and caving rule through three-dimensional physical simulation, and provide scientific basis for overhanging roof safety treatment.

[0006] The technical scheme of the utility model comprises:

[0007] The box body is provided with a slot at the bottom of one side wall, and the side walls of the box body are transparent;

[0008] The wood strip layer is used for simulating coal seam, and comprises a plurality of wood strips, which are laid on the bottom of the box body in length direction, and one end of the wood strips extends out of the slot;

[0009] The similar material layer is used for simulating rock layer, and is located on the wood strips in the box body, and the similar material layer comprises lower siltstone, fine-grained sandstone, mudstone and upper siltstone from bottom to top;

[0010] The load piece is used for simulating surface layer, and is located above the similar material layer;

[0011] The shooting device is located outside the side wall of the box body with slot, and is used for shooting the caving degree of the similar material layer.

[0012] Further, the scaling ratio of the simulation device is 1:200.

[0013] Further, the size of the box is 120 cm in length, 100 cm in width and 50 cm in height.

[0014] Further, the wood strip layer is provided with a gap with the side wall of the box.

[0015] Further, the distance of the gap is 10.5 cm.

[0016] Further, the width of the wood strip is 3 cm.

[0017] Further, the wood strip is at least two layers.

[0018] Further, the load includes bricks and sandbags laid on the similar material layer.

[0019] Further, the thickness ratio of the coal seam, the lower siltstone, the fine-grained sandstone, the mudstone and the upper siltstone is 3:7:4:5:5.

[0020] The technical scheme provided by the utility model has the following advantages compared with the prior art:

[0021] The wood strips of the wood strip layer are laid in the length direction on the bottom of the box in sequence, so that one end of the wood strip extends out of the notch of the side wall of the box, the wood strip layer is used to simulate the coal seam; the similar material layer is laid on the wood strip layer, and the similar material layer is laid in the order of the lower siltstone, the fine-grained sandstone, the mudstone and the upper siltstone from bottom to top, so as to simulate the rock layer; the load loading piece is arranged above the similar material layer, so as to simulate the pressure effect of the surface layer on the rock layer; the wood strip extending out of the notch is pulled out, so as to simulate the gradual excavation process of the coal seam of the coal mining face; the change of the rock layer inside the box is observed through the transparent side wall of the box, at the same time, the falling condition of the similar material layer (the rock layer) is shot in real time by the shooting device located outside the notch side of the box, the falling degree is recorded, and then the physical simulation of the suspended roof shape of the coal mining face end is realized. Compared with the prior art, the wood strip is pulled out to simulate the excavation of the coal seam, the stepped arc structure of the end suspended roof and the falling law are accurately restored, the problems of large error, high cost and insufficient dynamic observation of the traditional monitoring are solved, scientific basis is provided for the suspended roof processing opportunity and horizon selection, support selection and roof control scheme optimization, and the safety of coal mining is effectively improved.

[0022] Other advantages, objects and features of the utility model will be embodied partly through the following description, and will be understood by those skilled in the art through research and practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description, obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0024] Figure 1 It is the overall layout structure schematic diagram of the present application.

[0025] Figure 2 It is the box structure schematic diagram of the present application

[0026] Figure 3 It is the panoramic view of the present application device paving completion before excavation.

[0027] Figure 4 It is the roof caving state diagram of the present application working face advancing 24m.

[0028] Figure 5 It is the roof caving state diagram of the present application working face advancing 36m.

[0029] Figure 6 It is the roof caving state diagram of the present application working face advancing 42m.

[0030] Figure 7 It is the roof caving state diagram of the present application working face advancing 48m.

[0031] Figure 8 It is the roof arc crack development diagram of the present application working face advancing 60m.

[0032] Figure 9 It is the roof breakage line plan view of the present application working face advancing 66m.

[0033] Figure 10 It is the O-X breakage sketch of the present application.

[0034] Figure 11 It is the end suspension roof internal arc development actuality diagram of the present application.

[0035] Figure 12 It is the end suspension roof internal arc development schematic diagram of the present application.

[0036] Figure 13 It is the roof arc crack development diagram of the present application working face advancing 78m.

[0037] Figure 14 It is the roof arc crack development diagram of the present application working face advancing 96m.

[0038] Figure 15 is a periodic dynamic crack development graph when the working face advances 114m of the utility model;

[0039] Figure 16 is a roof crack development sketch when the working face advances 114m of the utility model;

[0040] Figure 17 is a roof arc crack development graph when the working face advances 126m of the utility model;

[0041] Figure 18 is a roof broken line and end overhanging top plan view after full mining of the utility model;

[0042] Figure 19 is a roof broken line and end overhanging top field measurement graph of the utility model;

[0043] Figure 20 is a roof broken line and end overhanging top numerical calculation result graph of the utility model;

[0044] Figure 21 is a roof broken line and end overhanging top physical simulation experiment result graph of the utility model.

[0045] Reference signs:

[0046] 1, box; 2, wooden strip; 3, lower siltstone; 4, fine-grained sandstone; 5, mudstone; 6, upper siltstone; 7, load piece. DETAILED DESCRIPTION

[0047] One specific embodiment of the utility model will be described in detail below in conjunction with the drawings, but it should be understood that the protection scope of the utility model is not limited by the specific embodiment.

[0048] In the description of the utility model, it should be understood that the orientation or position relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the technical scheme of the utility model and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the utility model.

[0049] In the description of the embodiment of the utility model, unless otherwise specified, the meaning of "a plurality of" is two or more than two.

[0050] As Figure 1 , Figure 2 ,Figure 3 The utility model provides a coal mine working face end suspension roof form physical simulation device, include:

[0051] The box 1 is equipped with the notched on the bottom of one side wall, and the side wall of box 1 is transparent;

[0052] The wood strip layer is used to simulate coal seam, and the wood strip layer includes a plurality of wood strips 2, the plurality of wood strips 2 are sequentially laid on the bottom of the box 1 along the length direction, and one end of the plurality of wood strips 2 extends out of the notch;

[0053] The similar material layer is used to simulate rock layer, and the similar material layer is located on the wood strip 2 in the box 1; the similar material layer sequentially includes lower siltstone 3, fine-grained sandstone 4, mudstone 5 and upper siltstone 6 from bottom to top;

[0054] The load 7 is used to simulate surface layer, and the load 7 is located above the similar material layer;

[0055] The shooting device is located outside the side wall of the box 1 with the notch, and the shooting device is used to shoot the caving degree of the similar material layer.

[0056] The size of the box 1 is 120 centimeters in length, 100 centimeters in width and 50 centimeters in height, the four sides and the bottom plate adopt 1 centimeter thick acrylic glass plate and angle iron fixing, and the top is open. The side wall is provided with a preset notch for inserting / extracting the wood strip 2 to simulate coal seam excavation, and the notch spacing is matched with the width of the wood strip layer; the similar material layer sequentially includes coal seam, siltstone, fine-grained sandstone 4, mudstone 5 and siltstone from bottom to top according to rock layer, and is made of different proportions of river sand, gypsum, titanium white and mica powder; the load 7 applies equivalent overburden load to the top of the similar material layer, and the camera (shooting device) is used to record the roof caving process from the upper part of the model and the strike direction.

[0057] The box 1, the wood strip layer and other components are integrated, the rock layer structure and the excavation scene are restored, the shooting device is matched to realize the visualization of the caving process, the problem that the traditional monitoring cannot dynamically capture the suspension roof form is solved, the foundation for accurately analyzing the suspension roof caving law is laid, the structure design is simple, the operation is convenient, and the core demand of coal mining simulation is matched.

[0058] In the embodiment provided by the utility model, the simulation device is according to the real object scaling component, and the specific scaling similarity criterion is as follows: The geometric similarity condition is: The gravity acceleration similarity condition is: The time similarity condition is: =0.07 The displacement similarity condition is: The internal friction angle similarity condition is: The strength, elastic modulus and cohesion similarity condition is: The force similarity condition is: = 8.3 x 10-8.

[0059] Ensure that the model matches the actual working condition of the geometry, mechanical parameters, can complete simulation of the end area of the working face of the strata distribution, and is convenient for experimental operation and observation. Avoid distortion caused by improper model size, ensure the accuracy of key data such as suspended roof span layer distribution and caving step, and improve the reliability of the experiment. Greatly reduce the simulation cost, avoid the error caused by boundary simplification in numerical simulation, and provide protection for the accurate restoration of the shape of the suspended roof and the caving law.

[0060] In the embodiments provided by the utility model, the wood strip layer is provided with gaps with the side walls of the box body 1 around, and the distance of the gaps is 10.5 cm.

[0061] 10.5 cm gap precisely matches the boundary coal pillar simulation requirement, balances the model space utilization rate and simulation authenticity, effectively simulates the support effect of the coal pillar on the roof, avoids deviation of the suspended roof caving law, and provides stable experimental conditions for accurately analyzing the mutual influence of the suspended roof and the boundary coal pillar.

[0062] In the embodiments provided by the utility model, the width of the wood strip 2 is 3 cm, corresponding to the actual excavation distance of 6 m, the camera takes a picture record every time the wood strip 2 is pulled out, and the loading height of the load 7 corresponds to the actual overburden 26 m layer.

[0063] The 3 cm wide wood strip 2 is matched with the single pulling-out length, the excavation step is precisely controlled, the wood strip 2 is pulled out to simulate coal seam excavation, the operation is simple, and the actual mining progress can be accurately corresponded, the suspended roof dynamic caving process can be quantitatively observed, and the accuracy and comparability of experimental data are improved.

[0064] In the embodiments provided by the utility model, the wood strip 2 is at least two layers, and is adapted to the simulation requirement of different coal seam thicknesses.

[0065] The multi-layer wood strip 2 is designed to adapt to the simulation scene of different thicknesses of coal seams, and the applicability of the device is enhanced. The stress of the roof and the suspended roof formation process under different thicknesses of coal seams can be accurately restored, the limitation of single coal seam thickness simulation is avoided, and diversified references for suspended roof treatment under different mining conditions are provided.

[0066] Meanwhile, the multi-layer wood strip 2 is designed to pull out the lower wood strip 2 first, so as to avoid friction between the wood strip 2 and the similar material layer due to pulling, and affect the accuracy of the caving degree.

[0067] In the embodiments provided by the utility model, the load 7 includes bricks and sandbags laid above the similar material layer, and is used for applying equivalent overburden load to the top of the similar material layer, and the loading height corresponds to the actual overburden 26 m layer.

[0068] The bricks and sandbags are used as the load piece 7, which is convenient to obtain and flexible to load, and can accurately simulate the overburden rock load. The load size can be adjusted according to the experimental requirements, and the hanging roof collapse characteristics under different overburden pressures are restored. Compared with the complex loading equipment, the cost is lower, the operation is safer, and the experimental feasibility is improved.

[0069] In the embodiment provided by the utility model, the thickness ratio of coal seam: lower siltstone 3: fine-grained sandstone 4: mudstone 5: upper siltstone 6 is 3:7:4:5:5.

[0070] The accurate rock thickness ratio design is combined with the targeted material proportioning to restore the physical and mechanical properties of different rock layers. The distribution law of the hanging roof across the layer can be accurately simulated, the influence of different rock layers on the shape of the hanging roof is revealed, the problem of insufficient restoration of the traditional simulated rock layer characteristics is solved, and a scientific basis is provided for the selection of the layer of the hanging roof treatment.

[0071] As shown in Figures 4 to 21 The example is taken in the actual mining size:

[0072] The boundary coal pillars with a length of 20 m are arranged on both sides of the box body 1, and the simulation excavation step is 6 m (two wooden strips 2 are extracted, and the same is true below). When the working face advances to 24 m (including the open-off cut), the immediate roof collapses, and the collapse height is 2 m; when the working face advances to 30 m, the roof collapse height increases to 11 m; when the working face advances to 36 m, the roof collapse height reaches 13 m. At this time, the roof collapse in the middle of the working face is more obvious, the roof collapse at the end of the working face is less, the roof collapse angle at the coal wall side of the working face is 45°, and the collapse angle at the open-off cut side is 65°.

[0073] The similar material layers are laid on the wood strip layer, and the rock layers are coal seam, siltstone, fine-grained sandstone 4, mudstone 5 and siltstone from bottom to top, and the thickness of each rock layer is set according to the similar ratio: the thickness of the coal seam model is 3 cm (corresponding to the prototype thickness of 5.9 m), the thickness of the siltstone (lower layer) model is 7 cm (corresponding to the prototype thickness of 15.45 m), the thickness of the fine-grained sandstone 4 model is 4 cm (corresponding to the prototype thickness of 7.44 m), the thickness of the mudstone 5 model is 5 cm (corresponding to the prototype thickness of 10.16 m), and the thickness of the siltstone (upper layer) model is 5 cm (corresponding to the prototype thickness of 9.7 m). The material ratio is determined according to the prototype lithology and the similar criterion: the coal seam ratio is river sand: gypsum: large white powder: mica powder = 20:20:1:5; the siltstone (upper layer) uses ratio 728, river sand 23.04 kg / cm, gypsum 1.02 kg / cm, and large white powder 1.54 kg / cm; the mudstone 5 uses ratio 946, river sand 11.52 kg / cm, gypsum 0.51 kg / cm, and large white powder 0.77 kg / cm; the fine-grained sandstone 4 uses ratio 737, river sand 11.20 kg / cm, gypsum 0.48 kg / cm, and large white powder 1.12 kg / cm; and the siltstone (lower layer) uses ratio 728, river sand 11.20 kg / cm, gypsum 0.32 kg / cm, and large white powder 1.28 kg / cm. It should be noted that the height of 1 cm here corresponds to the weight of the cover layer. During the laying process, mica powder is laid at the interface of each rock layer as a layered and structural fracture simulation material.

[0074] When the working face advances to 42 m, the roof caving height reaches 15 m, the break angle at the coal wall of the working face is 54°, and the break angle at the open-off cut side is 65°; when the working face advances to 48 m, the roof caving height at the end of the roof is 18 m, the roof caving height in the middle part develops to 22 m, and the immediate roof collapses with mining; at this time, the break angle at the working face is 68°. When the working face advances to 60 m, the roof caving height develops to 26 m. Through overhead photography, it is observed that the roof appears arc-shaped cracks, and the roof caving in the middle part of the working face is relatively sufficient. Due to the size constraint of the box 1, only half of the width of the working face is mainly simulated, and the focus is on the working face end overhang of the right side of the model.

[0075] When the working face advances to 66 m, the working face roof completely collapses behind the goaf, and the break is in the form of "O-X". The long side of the working face roof breaks first, and the short side breaks later. In the arc transition area of the long side and the short side of the working face (i.e., the arc overhang appears at the end of the working face), the overhang shape is in the form of "step arc triangular plate".

[0076] At the same time, during the experiment, the gangue part behind the short side arc-shaped break area is dug out for observation, and the size of the low-layer arc-shaped overhang inside the end overhang is small, and the size of the overhang reaches the maximum at the 26 m layer (the highest layer of the model), which is basically consistent with the field measurement and numerical calculation results.

[0077] When the working face advances to 78 m, the roof behind the working face goaf collapses periodically, and the periodic collapse step distance is 12 m. The new O-shaped circle is formed by the advanced development of cracks, and the interval is about 24 m (two periodic pressure step distances); the hanging roof behind the goaf has collapsed, and a new hanging roof is formed in the front end area of the working face, with a strike length of about 24 m and a dip length of about 22 m.

[0078] When the working face advances to 96 m, the roof collapses periodically, and the periodic collapse step distance is 18 m. The hanging roof behind the goaf has collapsed, and a new hanging roof is formed in the front end area of the working face, with a size of 21 m x 16 m. The collapse step distance of the end hanging roof is approximately equal to 2 periodic pressure step distances (18-24 m).

[0079] When the working face advances to 114 m, the roof collapses periodically, and the periodic collapse step distance is 18 m. However, the end hanging roof behind the working face goaf has not collapsed, and a new O-shaped circle is formed by the advanced development of cracks, with a position of advanced breakage of about 16 m and a working face advanced crack development of 6 m in front of the coal wall. During the experiment, the hanging roof collapse was observed by hand and machine photography, and the gangue was backfilled again.

[0080] When the working face advances to 126 m, the working face roof collapses periodically, and the periodic collapse step distance is 12 m. The working face front advanced crack development is obvious. The collapse of the working face rear goaf roof is mostly along the roof breakage angle, forming a step arc stable breakage pattern around the goaf. After the working face roof breaks, there is a certain range of arc area in the end area, which is a normal phenomenon. Even if the working face overburden fully collapses, it still exists stably. In production practice, the reasonable treatment horizon should be determined according to the roof breakage angle and the actual size of the hanging roof, so as to achieve the effect of doubling the work and halving the effort, and more economically and reasonably process the hanging roof.

[0081] Through field drilling measurement, it is found that the end roof of the 0-8 m horizon of the working face can generally collapse naturally, with a strike overhanging length of about 24 m and a collapse step distance of about 2 times the periodic pressure step distance. The 8-15 m horizon hanging roof can also break and collapse in time with the collapse of the 0-8 m horizon roof, but it shows integrity, which is the key object of hanging roof control and treatment. The 5-8 m horizon and 8-15 m horizon roof breakage is basically step-shaped arc development. The low horizon roof hanging roof area is small, and the high horizon roof hanging roof area is large. The 15-24 m horizon hanging roof basically remains stable, indicating that the end arc damage area exists at high horizon.

[0082] The numerical calculation of stress field and plastic zone distribution of different roof layers shows that the step distance of the end head hanging roof collapse is 24 m. Before and after the collapse of the hanging roof, the 4 m layer is within the working face caving zone, and the hanging roof basically collapses; the area of the 8-12 m layer reduces by about 60% after the collapse of the hanging roof; the 16-24 m layer is relatively stable. According to the distribution characteristics of the plastic zone of the roof along the working face, it is concluded that the hanging roof fracture is a stepped arc triangular block structure, and the higher the roof layer, the larger the arc-shaped hanging roof area.

[0083] The simulation experiment shows that the step distance of the end head hanging roof collapse is approximately equal to 2 times the periodic pressure step distance (18-24 m). There are arc-shaped transition regions on the long and short sides of the working face, which are the end head hanging roofs. The size of the low layer hanging roof is small, and the size of the high layer hanging roof is large, forming a stepped arc-shaped hanging roof. After the roof of the working face breaks, there is a certain range of arc-shaped area in the end head area, which is a normal phenomenon, and even after the overburden of the working face fully collapses, it still exists stably.

[0084] The analysis results of field drilling measurement, numerical calculation and physical simulation show that in the actual production process, the end head hanging roof of the working face is a natural phenomenon, the spatial form of the hanging roof is a stepped arc-shaped hanging roof, and the collapse step distance of the hanging roof is approximately equal to 2 times the periodic pressure step distance of the working face. Combined with the research results of rock stratum control in large mining height mining, the range of 2-3 times the mining height belongs to the category of equivalent direct roof, and the equivalent direct roof shows the characteristics of geological direct roof collapsing with mining. At the same time, the pressure sequence of the end head area lags behind the middle part of the working face, and the pressure intensity is weaker than that of the middle part of the working face, so the lagging collapse of the end head hanging roof is a normal phenomenon. The size of the end head hanging roof in the range of 1 times the mining height above the coal seam is small (the hanging roof area is about 10-50 m2), and the dynamic load or impact will not be generated when it collapses, so the working face roof is safe and basically does not need to be treated; the size of the hanging roof in the range of 1-3 times the mining height above the coal seam is large (the hanging roof area is about 50-120 m2), which is the main object that needs to be focused on and treated in production practice. The roof of the end head area outside the range of 3 times the mining height above the coal seam belongs to the hinged fracture zone and is irrelevant to the hanging roof.

[0085] The utility model has the following advantages:

[0086] 1. Three-dimensional accurate restoration, through the model frame of 1:200 similarity ratio and the targeted similar material proportioning, the different rock stratum characteristics and the working face excavation process are simulated, and the stepped arc-shaped structure of the end head hanging roof is accurately restored.

[0087] 2. Dynamic law visualization, the dynamic observation assembly is used to record the whole process of the hanging roof collapse in real time, and the cross-layer distribution law and the quantitative relationship between the collapse step distance and the periodic pressure are revealed.

[0088] 3. Low cost and high efficiency, compared with field drilling observation, the cost is greatly reduced, compared with numerical simulation, the accuracy is improved, a scientific basis is provided for the hanging roof treatment, and invalid treatment is reduced.

[0089] 4. Strong applicability, can adapt to different roof structure conditions, guide support selection and roof control scheme optimization, improve coal mining safety.

[0090] It should be noted that the undisclosed part or the part not specially mentioned in the utility model is prior art or conventional setting, and the specific structure and working principle will not be repeated. In this text, the term "including", "containing" or any other variant is intended to cover non-exclusive containing, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes the elements inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the existence of another identical element in the process, method, article or device including the element.

[0091] Although the embodiments of the utility model have been disclosed as above, it is not limited to the application listed in the specification and the embodiments. It can be fully applied to various fields suitable for the utility model. For those skilled in the art, other modifications can be easily realized. Therefore, the utility model is not limited to specific details and the figures shown and described herein without departing from the general concept defined by the claims and the equivalent scope.

Claims

1. A physical simulation device for the overhanging morphology of a coal mine working face, characterized in that, include: The box has a slot at the bottom of one side wall, and the side walls of the box are all transparent. The wooden strip layer includes several wooden strips, which are laid flat along the length of the bottom of the box, with one end of each wooden strip extending out of the groove. A similar material layer is located on the wooden strips inside the box. The similar material layer consists of a lower layer of siltstone, a fine-grained sandstone, a mudstone, and an upper layer of siltstone from bottom to top. The load-bearing component is located above a layer of similar material. A camera is located on the outside of the slotted sidewall of the housing, and the camera is used to photograph the slump of similar material layers.

2. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 1, characterized in that, The simulation device is scaled to 1:

200.

3. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 2, characterized in that, The dimensions of the box are 120 cm long × 100 cm wide × 50 cm high.

4. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 3, characterized in that, The wooden strip layer has gaps around its perimeter and are connected to the side walls of the box.

5. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 4, characterized in that, The distance of the gap is 10.5 centimeters.

6. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 2, characterized in that, The width of the wooden strip is 3 centimeters.

7. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 6, characterized in that, The wooden strips are at least two layers.

8. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 2, characterized in that, The load-bearing components include bricks and sandbags laid on top of a layer of similar material.

9. The physical simulation device for the overhanging morphology of a coal mine working face as described in claim 2, characterized in that, The thickness ratio of the coal seam: lower siltstone: fine-grained sandstone: mudstone: upper siltstone is 3:7:4:5:5.

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