Disaster-causing evaluation method for hidden disaster-causing factors of roof

Abstract

The invention relates to a roof hidden disaster-causing factor disaster-causing evaluation method, which aims at solving the problem of general survey of roof hidden disaster-causing factors, is based on two factors of nature and mining, is combined with an up-and-down well combined three-dimensional comprehensive detection mode of ground survey-ground exploration-underground exploration-construction monitoring, and clarifies the distribution form of coal seams and overlying strata, so that the disaster-causing evaluation of the roof hidden disaster-causing factors is realized. The method comprises the following steps: revealing roof rock stratum mechanical characteristics and stress field distribution, ascertaining coal pillar setting, roof suspension, unknown goaf, broken area, ground surface settlement and crack distribution, establishing a comprehensive evaluation index system in combination with mining conditions, evaluating the disaster-causing property of hidden disaster-causing factors of the roof, and providing effective support for effective prevention and control of subsequent roof disasters.

Description

Technical Field

[0001] The present application relates to the field of coal mine safety technology, and in particular, to a disaster assessment method for hidden disaster-causing factors of roof. Background Art

[0002] Coalfield geology has the remarkable characteristics of diverse coal-forming basin types, strong late-stage transformation, and complex coal seam occurrence conditions, which has formed a situation of multiple disasters such as roof, gas, water disasters, rock burst, and fire. The occurrence of the above disasters is controlled by various hidden factors, and the hidden factors of coal mines are time-varying, sudden, difficult to detect and difficult to prevent. If they are not well controlled, they are very likely to cause coal mine disasters. At present, the investigation of hidden disaster-causing geological factors is the key fundamental solution for the safe production of coal enterprises. However, the current survey method for hidden disaster-causing factors is relatively single, and with the proposal and development of technical models such as "long excavation and long exploration" and "exploration as excavation", as well as the emergence of guiding needs such as transparent and intelligent mining, the overall standardization of the current hidden disaster survey is insufficient, and the survey accuracy needs to be improved. In addition, the fundamental purpose of the hidden disaster factor survey is to serve disaster prevention and control, but the current hidden disaster factor survey only stays at the factor exploration level, and the evaluation of disaster risk is seriously insufficient, resulting in the evaluation of disaster risk is not comprehensive and accurate enough, and the actual role of evaluation cannot be fully played. Summary of the invention

[0003] In order to overcome at least one shortcoming in the prior art, the present application provides a disaster assessment method for hidden disaster-causing factors of roof.

[0004] In a first aspect, a method for evaluating hidden disaster-causing factors of roof is provided, comprising:

[0005] Conduct ground surveys on the target roof area and obtain ground survey results, including surface settlement data, surface crack data, rock outcrop data, and surface water and sand coverage data;

[0006] Conduct ground exploration of the roof target area to obtain ground exploration results, which include the structural characteristics of the overburden rock, and determine the type of the roof based on the structural characteristics of the overburden rock;

[0007] Conduct underground exploration of the target area of ​​the roof and obtain underground exploration results, including overburden structure, coal pillar boundary, goaf space boundary, water-rich area and water-rich characteristics;

[0008] For the roof target area, the vibration of tunneling and coal mining equipment is used as the seismic source, and the structural data are obtained through the analysis of vibration wave velocity and amplitude changes. The structural data includes advanced stress concentration and structural development;

[0009] Determine the type of disaster caused by hidden disaster-causing factors in the roof based on ground survey results, ground exploration results, underground exploration results, structural data and roof types;

[0010] Obtain factors related to the disaster type, determine the correlation evaluation weight and membership value corresponding to each factor, and obtain the danger level evaluation value of the disaster type based on the correlation evaluation weight and membership value; determine the danger level based on the danger level evaluation value, and formulate corresponding prevention and control measures based on the danger level.

[0011] In one embodiment, the ground survey includes one or more of ground exploration, aerial survey and remote sensing detection, and low-altitude aerial photography.

[0012] In one embodiment, downhole exploration includes one or more of downhole drilling, geological radar detection, in-hole transient electromagnetic detection, lidar detection, high-density electrical detection and seismic exploration.

[0013] In one embodiment, the disaster types caused by hidden disaster-causing factors in the roof include one or more of the following: support instability, roof collapse, roof shearing, water and sand burst, impact mine tremors, and abnormal mine pressure.

[0014] In one embodiment, the disaster type is roof collapse; factors related to roof collapse include weak rock formations, fracture zones, folds, faults, overlying coal pillars, goaf range, stress concentration, and support;

[0015] Determine the membership value corresponding to each factor according to the membership function corresponding to each factor;

[0016] Evaluation value of the risk level of roof collapse:

[0017] β=(A 11 ·B1+A 12 ·B2+A 13 ·B3+A 14 ·B4)·A1+(A 21 ·B5+A 22 ·B6+A 23 ·B7)·A2+B8A3

[0018] Among them, β is the risk evaluation value, A 11 , A 12 , A 13 , A 14 are the correlation evaluation weights corresponding to weak rock layers, broken zones, folds, and faults, respectively; B1, B2, B3, and B4 are the membership values ​​corresponding to weak rock layers, broken zones, folds, and faults, respectively; A 21 , A 22 , A 23are the correlation evaluation weights corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, respectively; B5, B6, and B7 are the membership values ​​corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, respectively; B8 is the membership value corresponding to the support, A1 is the sum of the correlation evaluation weights corresponding to the weak rock strata, broken zones, folds, and faults, A2 is the sum of the correlation evaluation weights corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, and A3 is the correlation evaluation weight corresponding to the support.

[0019] In one embodiment, the danger level is determined according to the danger level evaluation value, and corresponding prevention and control measures are formulated according to the danger level, including:

[0020] If the hazard level evaluation value β < 0.3, it is a safe level;

[0021] If 0.3≤β<0.5, it is a weak danger level and requires enhanced monitoring;

[0022] If 0.6≤β<0.8, it is a medium-risk level, and corresponding prevention and control measures need to be implemented for factors with a membership degree exceeding 0.6;

[0023] If 0.8≤β, it is a strong danger level, and mining activities need to be stopped and corresponding governance of all factors needs to be carried out.

[0024] In a second aspect, a disaster assessment system for hidden disaster-causing factors of roof is provided, comprising:

[0025] The ground survey module is used to conduct ground surveys on the target area of ​​the roof and obtain ground survey results, which include surface settlement data, surface crack data, rock outcrop data, and ground water-rich and covered sand data;

[0026] A ground exploration module is used to conduct ground exploration of the roof target area and obtain ground exploration results, which include the structural characteristics of the overburden rock and determine the type of the roof according to the structural characteristics of the overburden rock;

[0027] The underground exploration module is used to conduct underground exploration of the roof target area and obtain underground exploration results, which include overburden structure, coal pillar boundary, goaf space boundary, water-rich area and water-rich characteristics;

[0028] The structural data acquisition module is used to obtain structural data by using the vibration of tunneling and coal mining equipment as the seismic source in the roof target area, and analyzing the changes in vibration wave velocity and amplitude. The structural data includes advanced stress concentration and structural development.

[0029] A disaster type determination module is used to determine the disaster type caused by hidden disaster-causing factors of the roof according to ground survey results, ground exploration results, underground exploration results, structural data and roof types;

[0030] The evaluation module is used to obtain factors related to the disaster type, determine the correlation evaluation weight and membership value corresponding to each factor, and obtain the danger level evaluation value of the disaster type based on the correlation evaluation weight and membership value; determine the danger level based on the danger level evaluation value, and formulate corresponding prevention and control measures based on the danger level.

[0031] Compared with the prior art, the present application has the following beneficial effects: the disaster causality evaluation method of hidden disaster-causing factors of roof in the present application, aimed at the difficulty of surveying hidden disaster-causing factors of roof, is based on the two major factors of nature and mining, and combines the three-dimensional comprehensive detection method of "ground investigation-ground exploration-underground exploration-construction monitoring" both above and below the well, to clarify the distribution morphology of coal seams and overburden, reveal the mechanical characteristics and stress field distribution of roof rock strata, and find out the distribution of coal pillars, hanging roofs, unknown goafs, broken areas, surface subsidence and cracks. Combined with mining conditions, a comprehensive evaluation index system is established to evaluate the catastrophicity of hidden disaster-causing factors of roof, and provide effective support for the effective prevention and control of subsequent roof disasters. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present application may be better understood by referring to the following description given in conjunction with the accompanying drawings, which together with the following detailed description are included in this specification and form a part of this specification. In the drawings:

[0033] Figure 1 A flowchart of a method for evaluating hidden disaster-causing factors of a roof according to an embodiment of the present application is shown;

[0034] Figure 2 A schematic diagram of the classification of factors related to roof collapse is shown. DETAILED DESCRIPTION

[0035] The exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual embodiments are described in the specification. However, it should be understood that many implementation-specific decisions can be made in the process of developing any such actual embodiments in order to achieve the specific goals of the developer, and these decisions may vary from embodiment to embodiment.

[0036] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure closely related to the scheme according to the present application is shown in the drawings, while other details that are not closely related to the present application are omitted.

[0037] It should be understood that the present application is not limited to the described implementation forms due to the following description with reference to the accompanying drawings. In this article, where feasible, the embodiments can be combined with each other, features between different embodiments can be replaced or borrowed, and one or more features can be omitted in one embodiment.

[0038] The present application provides a disaster causation evaluation method for hidden disaster-causing factors in the roof. By conducting a classified and source-based census of hidden disaster-causing factors in the roof, and constructing a disaster impact evaluation index system based on the census results, the disaster-causing degree of each factor is quantitatively evaluated, so as to achieve source-based, advanced and precise control of roof disasters in mines, provide strong support for safe and efficient mining of coal mines, and overcome existing technical defects.

[0039] Figure 1 A flowchart of a method for evaluating the hidden disaster-causing factors of a roof according to an embodiment of the present application is shown. Figure 1 , methods include:

[0040] Step S1, conducting a ground survey on the roof target area to obtain ground survey results, which include surface settlement data, surface crack data, rock outcrop data, and surface water-rich and covered sand data.

[0041] First, basic data on roof disasters should be obtained and analyzed. Basic data on drilling, logging, mud logging, and rock mechanics of the surveyed mine and surrounding mines can be collected to conduct a preliminary screening of hidden disaster factors in the surveyed mine roof and identify possible hidden disaster factors in the roof that have not been identified.

[0042] Then, a ground survey is conducted on the target area of ​​the roof, which includes one or more of ground reconnaissance, aerial survey and remote sensing detection, and low-altitude aerial photography.

[0043] Step S2, performing ground exploration on the roof target area to obtain ground exploration results, the ground exploration results including overburden structure characteristics, and determining the type of the roof according to the overburden structure characteristics.

[0044] Here, the ground exploration method includes ground drilling. The layout of ground drilling is as follows: the total number of holes is designed according to the exploration area, and holes are arranged at intervals of 200m×200m. The method of acquiring drilling data includes: coring the entire hole section, and conducting mechanical tests on the rock strata of the roof of the core coal seam, using logging and mud logging to identify the strata, and testing the ground stress distribution in the mine area through the orthogonal dipole acoustic wave method to identify the overburden structure in the mine area, reveal the characteristics of the overburden structure, and determine the basic classification of the roof.

[0045] Step S3, performing underground exploration on the roof target area to obtain underground exploration results, which include overburden structure, coal pillar boundary, goaf space boundary, water-rich area and water-rich characteristics.

[0046] Specifically, downhole exploration includes one or more of downhole drilling, geological radar detection, in-hole transient electromagnetic detection, lidar detection, high-density electrical detection and seismic exploration.

[0047] Among them, the hole arrangement method for underground drilling is: holes are arranged at intervals of 200m×200m. The locations of the holes are detection areas where the ground detection accuracy has not been reached or realized. Through underground drilling, the overburden structure, coal seam spacing, and coal seam roof distribution morphology are detected to achieve the exploration of overburden structure, coal pillar boundaries, goaf space boundaries, water-rich areas, and water-rich characteristics. Among them, water-rich characteristics include water richness, permeability, recharge conditions, water storage space, water pressure, and water quality characteristics.

[0048] Geological radar detection is a detailed detection of the coal-rock interface, which integrates the ground detection results to make a detailed division of the roof overburden structure.

[0049] Laser radar detection is to detect the boundaries of goaf. When laser radar detection shows the existence of goaf, additional drilling detection projects are required to further obtain data on the scope of the goaf and improve the detection accuracy of the goaf. The supplementary drilling design passes through the goaf. During the drilling process, the water and gas storage conditions in the goaf are detected by using orifice gas and water monitoring instruments, and the gas and water discharge and extraction can be achieved as much as possible.

[0050] The high-density electrical method can accurately detect the water-rich characteristics of rock strata and goafs, and can be mutually verified with lidar detection and downhole drilling. Seismic exploration can detect and analyze earthquakes, thick hard roof sand bodies, and structural analysis.

[0051] Step S4, using the vibration of the tunneling and coal mining equipment as the seismic source for the roof target area, and obtaining structural data by analyzing the changes in vibration wave velocity and amplitude, the structural data including advanced stress concentration and structural development.

[0052] By using the vibration of tunneling and coal mining equipment as the seismic source and through dynamic wave processing, further detection of the structural area can be carried out with an accuracy of 1m.

[0053] Step S5, determining the disaster type caused by the hidden disaster-causing factors of the roof according to the ground investigation results, ground exploration results, underground exploration results, structural data and the type of the roof.

[0054] According to the types of hidden factors of the roof, combined with the analysis of the three-dimensional comprehensive detection results of "ground investigation-ground exploration-underground exploration-construction monitoring" both above and below the well, the hidden disaster-causing factors of the roof are classified according to "soft rock roof, structural broken roof, hard roof, shallow buried thin bedrock roof, deep buried high stress roof". The types of disasters caused by hidden disaster-causing factors of the roof are one or more of support instability, roof collapse, roof cutting, water and sand burst, impact mine earthquake and abnormal mine pressure. Here, based on the obtained ground investigation results, ground exploration results, underground exploration results, structural data and roof categories, the type of disaster caused by the hidden disaster-causing factors of the roof can be directly determined. This process is a conventional method in this field and will not be repeated here.

[0055] Step S6, obtain factors related to the disaster type, determine the correlation evaluation weight and membership value corresponding to each factor, and obtain the danger level evaluation value of the disaster type based on the correlation evaluation weight and membership value; determine the danger level based on the danger level evaluation value, and formulate corresponding prevention and control measures based on the danger level.

[0056] The disaster-causing evaluation method for hidden disaster-causing factors of roof in this embodiment, aimed at the difficulty of surveying hidden disaster-causing factors of roof, is based on two major factors, namely natural and mining, and combines a three-dimensional comprehensive detection method of "ground investigation-ground exploration-underground exploration-construction monitoring" both above and below the well, to clarify the distribution morphology of coal seams and overburden, reveal the mechanical characteristics and stress field distribution of roof rock strata, and find out the distribution of coal pillars, hanging roof, unknown goaf, broken areas, surface subsidence and cracks. Combined with mining conditions, a comprehensive evaluation index system is established to evaluate the catastrophicity of hidden disaster-causing factors of roof, so as to provide effective support for the effective prevention and control of subsequent roof disasters.

[0057] In one embodiment, taking roof collapse as an example to conduct disaster assessment, according to the correlation of roof collapse factors, three roof collapse-related factors are divided into coal seam occurrence conditions, mining technology, and support. Coal seam occurrence conditions are subdivided into weak rock formations, broken zones, folds, and faults. Mining technology is subdivided into overlying legacy coal pillars, goaf area, and stress concentration. Figure 2 The schematic diagram of the classification of factors related to roof caving is shown. Specifically, the disaster type is roof caving; the factors related to roof caving include weak rock formations, broken zones, folds, faults, overlying coal pillars, goaf area, stress concentration, and support; Table 1 shows the correlation evaluation weights of factors related to roof caving.

[0058] The membership value corresponding to each factor is determined according to the membership function corresponding to each factor; Table 2 shows the membership function of weak rock formations, Table 3 shows the membership function of broken zones, Table 4 shows the membership function of folds, Table 5 shows the membership function of faults, and Table 6 shows the membership function of overlying coal pillars. Table 7 shows the membership function of goaf area, Table 8 shows the membership function of stress concentration, and Table 9 shows the membership function of support. The membership value corresponding to each factor can be determined by looking up the table.

[0059] Evaluation value of the risk level of roof collapse:

[0060] β=(A 11 ·B1+A 12 ·B2+A 13 ·B3+A 14 ·B4)·A1+(A 21 ·B5+A 22 ·B6+A 23 ·B7)·A2+B8A3

[0061] Among them, β is the risk evaluation value, A 11 , A 12 , A 13 , A 14 are the correlation evaluation weights corresponding to weak rock layers, broken zones, folds, and faults, respectively; B1, B2, B3, and B4 are the membership values ​​corresponding to weak rock layers, broken zones, folds, and faults, respectively; A 21 , A 22 , A 23 are the correlation evaluation weights corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, respectively; B5, B6, and B7 are the membership values ​​corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, respectively; B8 is the membership value corresponding to the support, A1 is the sum of the correlation evaluation weights corresponding to the weak rock strata, broken zones, folds, and faults, A2 is the sum of the correlation evaluation weights corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, and A3 is the correlation evaluation weight corresponding to the support.

[0062] Table 1 Correlation evaluation weights of roof collapse factors

[0063] factor Weight Factor Weight Factor Weight Coal seam occurrence conditions (A1) 0.577 Mining technical conditions (A2) 0.322 Support A3 0.110 Weak rock layer (A11) 0.305 Overlying legacy coal pillar (A21) 0.147 Support (A31) 0.110 Broken Zone (A12) 0.068 Goaf area (A22) 0.102 Fold (A13) 0.101 Stress concentration (A23) 0.073 Fault (A14) 0.103 Table 2 Membership function of weak rock formation

[0064]

[0065] Table 3 Membership function of broken zone

[0066]

[0067] Table 4 Fold membership function

[0068] Fold length (B3) l≤50m 50m<l≤200m 200m<l≤500m 500m<l≤1000m1000m<l Membership 0.2 0.4 0.6 0.81.0

[0069] Table 5 Fault membership function

[0070] Fault drop (B4) d≤5m <h2 style=";text-align:left;direction:ltr">5m <d≤10m <h2 style=";text-align:left;direction:ltr"> 10m<d≤15m 15m<ld≤20m20m<d Membership 0.2 0.4 0.6 0.81.0

[0071] Table 6 Membership function of overlying coal pillar

[0072] Distance between overlying coal pillar and coal seam (B5) a>60m 45m <d≤60m <h2 style=";text-align:left;direction:ltr">35m <d≤45m <h2 style=";text-align:left;direction:ltr"> 20m<ld≤35m d<20m Membership 0.2 0.4 0.6 0.8 1.0

[0073] Table 7 Membership function of goaf area range

[0074] Goaf area (B6) <![CDATA[b≤10m 2 ]]> <![CDATA[10m 2 <b≤50m 2 ]]> <![CDATA[50m 2 <b≤200m 2 ]]> <![CDATA[200m 2 <b≤500m 2 ]]> <![CDATA[500m 2 <d]]> Membership 0.2 0.4 0.6 0.8 1.0

[0075] Table 8 Stress concentration membership function

[0076] Stress concentration factor (B7) λ≤1.2 1.2<λ≤1.5 1.5<λ≤1.8 1.8<λ≤2.02.0<λ Membership 0.2 0.4 0.6 0.81.0

[0077] Table 9 Stress concentration membership function

[0078] Support rationality (B8) Normal support Local failure of support Serious failure Membership 0.2 0.8 1.0

[0079] In one embodiment, step S6, determining the danger level according to the danger level evaluation value, and formulating corresponding prevention and control measures according to the danger level, includes:

[0080] If the hazard level evaluation value β < 0.3, it is a safe level;

[0081] If 0.3≤β<0.5, it is a weak danger level and requires enhanced monitoring;

[0082] If 0.6≤β<0.8, it is a medium-risk level, and corresponding prevention and control measures need to be implemented for factors with a membership degree exceeding 0.6;

[0083] If 0.8≤β, it is a strong danger level, and mining activities need to be stopped and corresponding governance of all factors needs to be carried out.

[0084] Based on the same inventive concept as the method for evaluating the hidden disaster-causing factors of roof, this embodiment also provides a corresponding system for evaluating the hidden disaster-causing factors of roof, including:

[0085] The ground survey module is used to conduct ground surveys on the target area of ​​the roof and obtain ground survey results, which include surface settlement data, surface crack data, rock outcrop data, and ground water-rich and covered sand data;

[0086] A ground exploration module is used to conduct ground exploration of the roof target area and obtain ground exploration results, which include the structural characteristics of the overburden rock and determine the type of the roof according to the structural characteristics of the overburden rock;

[0087] The underground exploration module is used to conduct underground exploration of the roof target area and obtain underground exploration results, which include overburden structure, coal pillar boundary, goaf space boundary, water-rich area and water-rich characteristics; the structural data acquisition module is used to use the vibration of tunneling and coal mining equipment as the seismic source for the roof target area, and obtain structural data through vibration wave velocity and amplitude change analysis, which includes advanced stress concentration and structural development;

[0088] A disaster type determination module is used to determine the disaster type caused by hidden disaster-causing factors of the roof according to ground survey results, ground exploration results, underground exploration results, structural data and roof types;

[0089] The evaluation module is used to obtain factors related to the disaster type, determine the correlation evaluation weight and membership value corresponding to each factor, and obtain the danger level evaluation value of the disaster type based on the correlation evaluation weight and membership value; determine the danger level based on the danger level evaluation value, and formulate corresponding prevention and control measures based on the danger level.

[0090] The disaster causation assessment system for hidden disaster factors on the roof of this embodiment has the same inventive concept as the disaster causation assessment method for hidden disaster factors on the roof mentioned above, so the specific implementation method of this system can be seen in the implementation example part of the disaster causation assessment method for hidden disaster factors on the roof mentioned above, and its technical effect corresponds to the technical effect of the above method, which will not be repeated here.

[0091] The above are only various implementations of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for evaluating hidden disaster-causing factors of roof, characterized in that: include: Conducting ground surveys on the target roof area to obtain ground survey results, including surface settlement data, surface crack data, rock outcrop data, and surface water-rich and covered sand data; Conducting ground exploration on the roof target area to obtain ground exploration results, wherein the ground exploration results include overburden structure characteristics, and determining the type of the roof according to the overburden structure characteristics; Conducting underground exploration of the target area of ​​the roof to obtain underground exploration results, wherein the underground exploration results include overburden structure, coal pillar boundary, goaf space boundary, water-rich area and water-rich characteristics; Using the vibration of tunneling and coal mining equipment as the seismic source for the target area of ​​the roof, the structural data are obtained by analyzing the changes in vibration wave velocity and amplitude, and the structural data include advanced stress concentration and structural development; Determine the type of disaster caused by hidden disaster-causing factors of the roof according to the ground survey results, the ground exploration results, the downhole exploration results, the structural data and the type of the roof; Obtaining factors related to the disaster type, determining a correlation evaluation weight and a membership value corresponding to each factor, and obtaining a danger level evaluation value of the disaster type according to the correlation evaluation weight and the membership value; The hazard level is determined based on the hazard level evaluation value, and corresponding prevention and control measures are formulated based on the hazard level.

2. The method according to claim 1, characterized in that The ground survey includes one or more of ground exploration, aerial survey and remote sensing detection, and low-altitude aerial photography.

3. The method according to claim 1, characterized in that The downhole exploration includes one or more of downhole drilling, geological radar detection, in-hole transient electromagnetic detection, lidar detection, high-density electrical detection and seismic exploration.

4. The method according to claim 1, characterized in that The types of disasters caused by the hidden disaster-causing factors of the roof include one or more of the following: support instability, roof collapse, roof shearing, water and sand burst, impact mine earthquake and abnormal mine pressure.

5. The method according to claim 1, characterized in that The disaster type is roof collapse; factors related to roof collapse include weak rock formations, fracture zones, folds, faults, overlying coal pillars, goaf area, stress concentration, and support; Determine the membership value corresponding to each factor according to the membership function corresponding to each factor; The evaluation value of the risk level of roof falling is: β=(A 11 ·B1+A 12 ·B2+A 13 ·B3+A 14 ·B4)·A1+(A 21 ·B5+A 22 ·B6+A 23 ·B7)·A2+B8A3, where β is the risk assessment value, A 11 , A 12 , A 13 , A 14 are the correlation evaluation weights corresponding to weak rock layers, broken zones, folds, and faults, respectively; B1, B2, B3, and B4 are the membership values ​​corresponding to weak rock layers, broken zones, folds, and faults, respectively; A 21 , A 22 , A 23 are the correlation evaluation weights corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, respectively; B5, B6, and B7 are the membership values ​​corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, respectively; B8 is the membership value corresponding to the support, A1 is the sum of the correlation evaluation weights corresponding to the weak rock strata, broken zones, folds, and faults, A2 is the sum of the correlation evaluation weights corresponding to the overlying legacy coal pillars, goaf area range, and stress concentration, and A3 is the correlation evaluation weight corresponding to the support.

6. The method according to claim 1, characterized in that The hazard level is determined according to the hazard level evaluation value, and corresponding prevention and control measures are formulated according to the hazard level, including: If the hazard level evaluation value β < 0.3, it is a safe level; If 0.3≤β<0.5, it is a weak danger level and requires enhanced monitoring; If 0.6≤β<0.8, it is a medium-risk level, and corresponding prevention and control measures need to be implemented for factors with a membership degree exceeding 0.6; If 0.8≤β, it is a strong danger level, and mining activities need to be stopped and corresponding governance of all factors needs to be carried out.

7. A disaster assessment system for hidden disaster factors of roof, characterized in that: include: A ground survey module is used to conduct a ground survey on the roof target area and obtain ground survey results, which include surface settlement data, surface crack data, rock outcrop data, and surface water-rich and covered sand data; A ground exploration module is used to conduct ground exploration on the roof target area, obtain ground exploration results, and the ground exploration results include the structural characteristics of the overburden rock, and determine the type of the roof according to the structural characteristics of the overburden rock; An underground exploration module is used to conduct underground exploration of the roof target area and obtain underground exploration results, wherein the underground exploration results include overburden structure, coal pillar boundary, goaf space boundary, water-rich area and water-rich characteristics; The structural data acquisition module is used to obtain structural data by using the vibration of the tunneling and coal mining equipment as the seismic source in the roof target area, and analyzing the changes in vibration wave velocity and amplitude, wherein the structural data includes advanced stress concentration and structural development; A disaster type determination module, used to determine the disaster type caused by hidden disaster-causing factors of the roof according to the ground survey results, the ground exploration results, the downhole exploration results, the structural data and the type of the roof; An evaluation module is used to obtain factors related to the disaster type, determine the correlation evaluation weight and membership value corresponding to each factor, and obtain a danger level evaluation value of the disaster type according to the correlation evaluation weight and membership value; The hazard level is determined based on the hazard level evaluation value, and corresponding prevention and control measures are formulated based on the hazard level.

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