Stability monitoring device and system for coal and rock mass exploitation

Abstract

The utility model discloses a stability monitoring device and system for coal and rock mass exploitation. The stability monitoring device comprises a stressometer, a vibration sensor, a transmission module used for transmitting interaction force and vibration frequency to the stressometer and the vibration sensor, and a fixing module arranged below the transmission module and used for fixing the stressometer. The stability monitoring system comprises the coal and rock mass stability monitoring device and an early warning platform arranged on the ground and connected with the coal and rock mass stability monitoring device. In the technical scheme of the utility model, the transmission module is in rigid contact with the inner wall of the drill hole of the coal and rock mass, thereby greatly reducing the loss of transmitting the internal interaction force and vibration frequency of the coal and rock mass around the drill hole to the stressometer and the vibration sensor, and avoiding the flexible contact between the stressometer or the vibration sensor and the inner wall of the drill hole in the prior art. Therefore, the internal interaction force and the vibration frequency are greatly lost. Therefore, measured data can be more accurate and comprehensive.

Description

Technical Field

[0001] The utility model belongs to the technical field of coal mining safety monitoring, and in particular relates to a stability monitoring device and system for coal and rock mining. Background Art

[0002] my country's coal mining progresses from shallow strata to deeper layers. As mining depth increases, the forces acting on the coal and rock mass change (i.e., stress changes), leading to fractures and increased gas concentrations. To ensure mining safety, monitoring devices are required to monitor the coal and rock mass during mining.

[0003] In the prior art, a strain gauge is usually used to measure the internal force (ie, stress) of underground coal and rock masses during mining, and a vibration sensor is used to measure the vibration generated by the fracture of underground coal and rock masses during mining.

[0004] However, firstly, when the monitoring device is placed in a coal-rock borehole, the strain gauge is in flexible contact with the borehole wall, meaning that the strain gauge will buffer (e.g., absorb or reduce) the internal forces exerted on the coal-rock during mining, resulting in the stress value measured by the strain gauge being less accurate (i.e., roughly accurate but not precise). Secondly, when the vibration sensor is placed in a coal-rock borehole, the vibration sensor is also in flexible contact with the borehole wall, meaning that the vibration sensor will also buffer (e.g., absorb or reduce) the vibration frequency of the coal-rock during mining, resulting in the vibration frequency value measured by the vibration sensor being less accurate (i.e., roughly accurate but not precise).

[0005] That is, the strain gauge or vibration sensor in the existing monitoring device is in flexible contact with the inner wall of the borehole, which causes loss of the interaction force transmitted to the strain gauge and the vibration frequency transmitted to the vibration sensor, resulting in low accuracy of the measured data.

[0006] Therefore, there is an urgent need for a coal rock monitoring device that reduces losses and thus greatly improves data measurement accuracy (ie, makes the data accurate). Utility Model Content

[0007] In order to solve the above technical problems, the utility model provides a stability monitoring device and system for coal rock mining, which not only reduces the loss, that is, greatly improves the measurement accuracy of single data, but also makes the comprehensive evaluation of multiple data more comprehensive or comprehensive.

[0008] The utility model provides a stability monitoring device for coal rock mining, which is characterized by comprising: a stress gauge arranged in a coal rock borehole for measuring the interaction force between the coal and rock around the borehole, a vibration sensor arranged in the coal rock borehole for measuring the vibration frequency of the coal rock fracture around the borehole, a transmission module for transmitting the interaction force and the vibration frequency to the stress gauge and the vibration sensor, and a fixing module arranged below the transmission module for fixing the stress gauge.

[0009] The transmission module includes a first cover and three energy transmission components. The circumferential surface of the first cover is provided with three positioning openings at equal intervals of 120 degrees. The three energy transmission components are clamped in the positioning openings.

[0010] The fixing module includes a second cover, three fixing components fixedly arranged above the second cover for fixing the strain gauge, and a support component fixedly arranged above the fixing component for making the energy transfer component rigidly contact the inner wall of the coal and rock borehole.

[0011] The strain gauge is fixedly arranged in a space surrounded by the three fixing components, and the vibration sensor is fixedly arranged on the lower surface of the second cover.

[0012] The above-mentioned stability monitoring device for coal rock mining is characterized in that it also includes a wireless communication module for transmitting the stress value measured by the stress gauge and the vibration frequency value measured by the vibration sensor to an early warning platform set up on the ground in real time, and the wireless communication module is fixedly set on the lower surface of the second cover body.

[0013] The above-mentioned stability monitoring device for coal rock mining is characterized in that: the energy transfer component is an energy transfer pin, the fixing component is a triangular plate, the expansion component is a conical head, and the stress gauge includes an elastomer for measuring the interaction force, and a strain gauge fixedly connected to the elastomer for measuring the deformation of the elastomer.

[0014] The above-mentioned stability monitoring device for coal rock mining is characterized in that it also includes a protective cover fixedly arranged on the lower surface of the second cover body for protecting the lower surface components of the second cover body, and a gas measurement module fixedly arranged on the other end of the protective cover for measuring the gas concentration value in the coal rock borehole.

[0015] The above-mentioned stability monitoring device for coal rock mining is characterized by further comprising a data storage module fixedly arranged on the lower surface of the second cover body for storing the stress value, the vibration frequency value and the gas concentration value.

[0016] The above-mentioned stability monitoring device for coal rock mining is characterized in that it also includes a power supply fixedly arranged on the lower surface of the second cover body for powering the stress gauge, the vibration sensor, the wireless communication module, the gas measurement module and the data storage module.

[0017] The utility model provides a coal-rock mining stability monitoring system, which is characterized by comprising the above-mentioned coal-rock mining stability monitoring device and an early warning platform arranged on the ground and connected to the coal-rock mining stability monitoring device.

[0018] The beneficial effects are analyzed as follows:

[0019] In the prior art, a strain gauge is usually used to measure the internal force (ie, stress) of underground coal and rock masses during mining, and a vibration sensor is used to measure the vibration generated by the fracture of underground coal and rock masses during mining.

[0020] However, firstly, when the monitoring device is placed in a coal-rock borehole, the strain gauge is in flexible contact with the borehole wall, meaning that the strain gauge will buffer (e.g., absorb or reduce) the internal forces exerted on the coal-rock during mining, resulting in the stress value measured by the strain gauge being less accurate (i.e., roughly accurate but not precise). Secondly, when the vibration sensor is placed in a coal-rock borehole, the vibration sensor is also in flexible contact with the borehole wall, meaning that the vibration sensor will also buffer (e.g., absorb or reduce) the vibration frequency of the coal-rock during mining, resulting in the vibration frequency value measured by the vibration sensor being less accurate (i.e., roughly accurate but not precise).

[0021] That is, in the existing monitoring device, the strain gauge or vibration sensor is in flexible contact with the inner wall of the borehole, so that the interaction force transmitted to the strain gauge and the vibration frequency transmitted to the vibration sensor are lost.

[0022] In the technical solution of the present invention, the three energy transfer components are clamped in the positioning openings of the transfer module. When the expansion component is axially pushed into the space surrounded by the above three energy transfer components, the energy transfer component will be pushed outward in the circumferential direction until one end of the energy transfer component is rigidly in contact with the inner wall of the borehole and the other end is in close contact with the strain gauge.

[0023] First, one end of the energy transfer component is in close contact with the inner wall of the borehole, and the other end is in close contact with the strain gauge, and the strain gauge is fixed in the space surrounded by the three fixed components, so that the strain gauge can measure the internal interaction force (i.e. stress) of the coal and rock mass around the borehole. Second, the strain gauge is fixedly connected in the space surrounded by the three fixed components, and a second cover body is fixedly connected to the bottom of the three fixed components. The lower surface of the second cover body is fixedly connected to a vibration sensor, so that the vibration sensor can measure the vibration (i.e. vibration frequency) generated when the coal and rock mass around the borehole is broken.

[0024] That is, firstly, it is precisely because one end of the energy transmission component is in close contact with the inner wall of the borehole and the other end is in close contact with the strain gauge that the loss of the internal force (i.e., stress) received by the strain gauge is greatly reduced. Secondly, it is precisely because one end of the energy transmission component is in close contact with the strain gauge, the strain gauge is fixedly set in the space surrounded by three fixed components, and the three fixed components are fixedly connected to the second cover below, and the second cover is fixedly connected to the vibration sensor below, so that the loss of the vibration frequency received by the vibration sensor is greatly reduced (i.e., high accuracy), that is, the data measured by the stress gauge and the vibration sensor are accurate. Thirdly, it is precisely because the stability monitoring device integrates the stress gauge and the vibration sensor (i.e., on the same device) that the measured data is comprehensive.

[0025] That is to say, the utility model provides a stability monitoring device for coal rock mining. Due to the rigid contact between the transmission module (specifically the energy transmission component) and the inner wall of the borehole, the loss of stress and vibration frequency received by the stability monitoring device (including the stress gauge and the vibration sensor) is greatly reduced, that is, the accuracy of the data measured by the stress gauge and the vibration sensor is greatly improved, and the multiple measured data make the measurement results more comprehensive.

[0026] This avoids the flexible contact between the stress gauge or vibration sensor and the inner wall of the borehole in the prior art, which results in a large loss of the interaction force transmitted to the stress gauge and the vibration frequency transmitted to the vibration sensor. That is, the data measured by the stress gauge and vibration sensor has low accuracy, and the data measured by a single device (for example, a stress gauge or a vibration sensor) is single.

[0027] Therefore, the technical solution provided by the present invention can greatly improve the accuracy and comprehensiveness of data measurement, while at the same time being low in cost and requiring low technical skills from the installers. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is an overall structural diagram of a stability monitoring device for coal and rock mining provided by the utility model;

[0029] Figure 2 for Figure 1 The structural diagram of the transfer module;

[0030] Figure 3 for Figure 1 The structural diagram of the remaining part after removing the transfer module;

[0031] Figure 4 for Figure 3 Front view of

[0032] Figure 5 for Figure 3Perspective structure diagram;

[0033] Figure 6 This is a structural diagram of the fixed module;

[0034] Figure 7 This is the structural diagram of the strain gauge;

[0035] Figure 8 Installation structure diagram for installing the strain gauge into the space surrounded by three fixing components;

[0036] Figure 9 A schematic diagram showing the areas, locations and numbers of stability monitoring devices placed in underground coal and rock masses;

[0037] Description of reference numerals:

[0038] Strain gauge 1; vibration sensor 2; wireless communication module 3; first cover 13;

[0039] Energy transfer assembly 4; positioning opening 5; second cover 6;

[0040] Fixing component 7; Expanding component 8; Elastic body 1-1; Strain gauge 1-2;

[0041] Protective cover 9; gas measurement module 10; data storage module 11; power supply 12. DETAILED DESCRIPTION

[0042] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are intended only to illustrate the relevant utility model and are not intended to limit the scope of the utility model. It should also be noted that, for ease of description, only the portions relevant to the utility model are shown in the accompanying drawings.

[0043] It should be noted that, in the absence of conflict, the embodiments of the present invention, that is, the features of the embodiments, can be combined with each other. The present invention will be described in detail below with reference to the embodiments and in conjunction with the accompanying drawings.

[0044] In the prior art, firstly, when a monitoring device is placed in a coal-rock borehole, the strain gauge is in flexible contact with the borehole wall, which means the strain gauge will buffer (e.g., absorb or reduce) the internal forces exerted on the coal-rock during mining, resulting in the stress value measured by the strain gauge being less accurate (i.e., roughly accurate but not precise). Secondly, when a vibration sensor is placed in a coal-rock borehole, the vibration sensor is also in flexible contact with the borehole wall, which means the vibration sensor will also buffer (e.g., absorb or reduce) the vibration frequency of the coal-rock during mining, resulting in the vibration frequency value measured by the vibration sensor being less accurate (i.e., roughly accurate but not precise).

[0045] That is, the strain gauge or vibration sensor in the existing monitoring device is in flexible contact with the inner wall of the borehole, which causes loss of the interaction force transmitted to the strain gauge and the vibration frequency transmitted to the vibration sensor, resulting in low accuracy of the measured data.

[0046] Based on this, the utility model provides a stability monitoring device and system for coal rock mining, which not only greatly improves the measurement accuracy of single data, but also makes the measurement more comprehensive or comprehensive through comprehensive evaluation of multiple data.

[0047] Figure 1 This is the overall structure diagram of a stability monitoring device for coal and rock mining provided by the utility model. Figure 2 for Figure 1 The structure diagram of the transfer module, Figure 3 for Figure 1 The structure diagram of the remaining part after removing the transfer module, Figure 4 for Figure 3 Front view of Figure 5 for Figure 3 Perspective structure diagram, Figure 6 This is the structural diagram of the fixed module. Figure 7 is the structural diagram of the strain gauge, Figure 8 The installation structure diagram for installing the strain gauge into the space surrounded by three fixing components is shown below. Figure 9 This is a schematic diagram showing the areas, locations, and numbers of stability monitoring devices placed in underground coal and rock masses.

[0048] See also Figures 1 to 6 The utility model provides a stability monitoring device for coal rock mining, comprising: a stress gauge 1 disposed in a coal rock borehole for measuring the interaction force between the coal and rock around the borehole; a vibration sensor 2 disposed in the coal rock borehole for measuring the vibration frequency of the coal rock fracture around the borehole; a transmission module for transmitting the interaction force and the vibration frequency to the stress gauge 1 and the vibration sensor 2; and a fixing module disposed below the transmission module for fixing the stress gauge 1.

[0049] The transmission module includes a first cover 13 and three energy transmission components 4. The circumferential surface of the first cover 13 is provided with three positioning openings 5 ​​with equal intervals of 120 degrees. The three energy transmission components 4 are clamped in the positioning openings 5.

[0050] The fixing module includes a second cover 6, three fixing components 7 fixedly arranged above the second cover 6 for fixing the strain gauge 1, and a support component 8 fixedly arranged above the fixing component 7 for making the energy transfer component 4 rigidly contact the inner wall of the coal and rock borehole.

[0051] The strain gauge 1 is fixedly arranged in a space surrounded by the three fixing components 7 , and the vibration sensor 2 is fixedly arranged on the lower surface of the second cover 6 .

[0052] It should be noted that the stability monitoring device for coal rock mining provided by the present invention is applied in the process of underground coal rock mining. The above-mentioned stability monitoring device can be installed by drilling in the vicinity of the coal rock to be mined. During the coal rock mining process, the stability of the coal rock around the drill hole during the coal rock mining process is determined based on the data measured by the stability monitoring device (for example, stress value and vibration frequency value).

[0053] The vibration sensor 2 may be a piezoelectric acceleration sensor.

[0054] In a specific implementation, after drilling a hole in the coal rock mass, the transfer module can be placed into the borehole first, and then the expansion component 8 of the fixed module can be inserted into the space surrounded by the three energy transfer components 4 of the transfer module. Since the energy transfer component 4 is clamped in the positioning opening 5 of the transfer module, when the expansion component 8 is axially pushed into the above-mentioned space, the energy transfer component 4 will be pushed outward circumferentially until one end of the energy transfer component 4 is rigidly in contact with the inner wall of the borehole, and the other end is in close contact with the strain gauge 1.

[0055] Furthermore, since the three fixing components 7 are fixedly arranged on the upper surface of the second cover body 6, the strain gauge 1 is fixedly arranged in the space surrounded by the three fixing components 7, so that the strain gauge 1 can accurately measure the internal interaction force (ie stress) of the coal and rock mass around the borehole.

[0056] Furthermore, since the stress gauge 1 is fixedly arranged in the space surrounded by the three fixed components 7, the three fixed components 7 are fixedly arranged on the upper surface of the second cover body 6, and the vibration sensor 2 is fixedly arranged on the lower surface of the second cover body 6, the vibration sensor 2 can accurately measure the vibration (i.e., vibration frequency) when the coal and rock mass around the borehole is broken.

[0057] The beneficial effects are analyzed as follows:

[0058] In the prior art, a strain gauge is usually used to measure the internal force (ie, stress) of underground coal and rock masses during mining, and a vibration sensor is used to measure the vibration generated by the fracture of underground coal and rock masses during mining.

[0059] However, firstly, when the monitoring device is placed in a coal-rock borehole, the strain gauge is in flexible contact with the borehole wall, meaning that the strain gauge will buffer (e.g., absorb or reduce) the internal forces exerted on the coal-rock during mining, resulting in the stress value measured by the strain gauge being less accurate (i.e., roughly accurate but not precise). Secondly, when the vibration sensor is placed in a coal-rock borehole, the vibration sensor is also in flexible contact with the borehole wall, meaning that the vibration sensor will also buffer (e.g., absorb or reduce) the vibration frequency of the coal-rock during mining, resulting in the vibration frequency value measured by the vibration sensor being less accurate (i.e., roughly accurate but not precise).

[0060] That is, in the existing monitoring device, the strain gauge or vibration sensor is in flexible contact with the inner wall of the borehole, so that the interaction force transmitted to the strain gauge and the vibration frequency transmitted to the vibration sensor are lost.

[0061] In the technical solution of the present invention, the three energy transfer components 4 are clamped in the positioning openings 5 ​​of the transfer module. When the expansion component 8 is axially pushed into the space surrounded by the above three energy transfer components 4, the energy transfer component 4 will be pushed outward in the circumferential direction until one end of the energy transfer component 4 is rigidly in contact with the inner wall of the borehole and the other end is in close contact with the strain gauge 1.

[0062] First, one end of the energy transfer component 4 is in close contact with the inner wall of the borehole, and the other end is in close contact with the stress gauge 1, and the stress gauge 1 is fixed in the space surrounded by the three fixed components 7, so that the stress gauge 1 can measure the internal interaction force (i.e. stress) of the coal and rock mass around the borehole. Second, the stress gauge 1 is fixedly connected in the space surrounded by the three fixed components 7, and the second cover body 6 is fixedly connected below the three fixed components 7. The lower surface of the second cover body 6 is fixedly connected to the vibration sensor 2, so that the vibration sensor 2 can measure the vibration (i.e. vibration frequency) generated when the coal and rock mass around the borehole is broken.

[0063] That is, firstly, it is precisely because one end of the energy transfer component 4 is in close contact with the inner wall of the borehole and the other end is in close contact with the strain gauge 1 that the loss of the internal force (i.e., stress) received by the strain gauge 1 is greatly reduced. Secondly, it is precisely because one end of the energy transfer component 4 is in close contact with the strain gauge 1, and the strain gauge 1 is fixedly set in the space surrounded by the three fixing components 7, and the three fixing components 7 are fixedly connected to the second cover 6 below, and the second cover 6 is fixedly connected to the vibration sensor 2 below, that the loss of the vibration frequency received by the vibration sensor 2 is greatly reduced (i.e., high accuracy), that is, the data measured by the stress gauge 1 and the vibration sensor 2 are accurate. Thirdly, it is precisely because the stability monitoring device integrates the stress gauge 1 and the vibration sensor 2 (i.e., on the same device) that the measured data is comprehensive.

[0064] That is to say, the utility model provides a stability monitoring device for coal rock mining. Since the transmission module (specifically the energy transmission component 4) is in rigid contact with the inner wall of the borehole, the loss of stress and vibration frequency received by the stability monitoring device (including the stress gauge 1 and the vibration sensor 2) is greatly reduced, that is, the accuracy of the data measured by the stress gauge 1 and the vibration sensor 2 is greatly improved, and the multiple measured data make the measurement results more comprehensive.

[0065] This avoids the flexible contact between the stress gauge or vibration sensor and the inner wall of the borehole in the prior art, which results in a large loss of the interaction force transmitted to the stress gauge and the vibration frequency transmitted to the vibration sensor. That is, the data measured by the stress gauge and vibration sensor has low accuracy, and the data measured by a single device (for example, a stress gauge or a vibration sensor) is single.

[0066] Therefore, the technical solution provided by the present invention can greatly improve the accuracy and comprehensiveness of data measurement, while at the same time being low in cost and requiring low technical skills from the installers.

[0067] In the above-mentioned embodiment, a stability monitoring device for coal and rock mining is introduced. In another embodiment of the present invention, the stability monitoring device further includes a wireless communication module for real-time data transmission.

[0068] See also Figure 5 It also includes a wireless communication module 3 for transmitting the stress value measured by the fixed component stress gauge 1 and the vibration frequency value measured by the fixed component vibration sensor 2 to an early warning platform set on the ground in real time. The fixed component wireless communication module 3 is fixedly set on the lower surface of the second cover body 6 of the fixed component.

[0069] In a specific implementation, the wireless communication module 3 fixedly connected to the bottom surface of the second cover body 6 can send the data measured by the stress gauge 1 and the vibration sensor 2 in real time, so as to analyze the stability of the coal and rock mass around the borehole based on the above measurement data.

[0070] It is precisely because the wireless communication module 3 can send the measured data in real time that the data analysis is real-time.

[0071] The above-mentioned embodiment introduces that the stability monitoring device also includes a wireless communication module for real-time data transmission. In another embodiment of the present invention, the specific names of the energy transfer component 4, the fixing component 7, and the expansion component 8, as well as the composition of the strain gauge 1 are introduced.

[0072] For example, the energy transfer component 4 is an energy transfer pin, the fixing component 7 is a triangular plate, the expansion component 8 is a conical head, and the strain gauge 1 includes an elastic body 1-1 for measuring the interaction force, and a strain gauge 1-2 fixedly connected to the elastic body 1-1 for measuring the deformation of the elastic body 1-1.

[0073] It should be noted that the energy transmission component 4 is tightly connected to the elastic body 1-1 of the strain gauge 1. For example, see Figure 7 , Figure 7 This is a structural diagram of the stress gauge provided by the utility model.

[0074] In the above-described embodiment, the specific names of the energy transfer component 4, the fixing component 7, and the expansion component 8 are introduced, as well as the composition of the strain gauge 1. In another embodiment of the present invention, the stability monitoring device is introduced to further include a gas measurement module for measuring gas concentration.

[0075] Continue to see Figure 1 , and also includes a protective cover 9 fixedly set on the lower surface of the second cover body 6 for protecting the lower surface components of the second cover body 6, and a gas measuring module 10 for measuring the gas concentration value in the coal rock borehole is fixedly set at the other end of the protective cover 9.

[0076] In a specific implementation, the gas measurement module 10 can measure the gas concentration value in the borehole, so as to determine whether the coal and rock mass around the borehole can be mined safely based on the gas concentration value.

[0077] In the above-mentioned embodiment, the stability monitoring device further includes a gas measuring module for measuring gas concentration. In another embodiment of the present invention, the stability monitoring device further includes a data storage module 11 for storing data.

[0078] Continue to see Figure 5 , and also includes a data storage module 11 fixedly arranged on the lower surface of the second cover 6 for storing stress values, vibration frequency values ​​and gas concentration values.

[0079] In a specific implementation, the stress meter 1 and the vibration sensor 2 can measure stress value and vibration frequency respectively, and the data storage module 11 can store the above data so as to analyze and compare the above data to determine the stability of the coal and rock mass around the borehole.

[0080] In the above-mentioned embodiment, the stability monitoring device further includes a data storage module 11 for storing data. In another embodiment of the present invention, the stability monitoring device further includes a power supply for continuously supplying power to the above-mentioned modules.

[0081] Continue to see Figure 5, and also includes a power supply 12 fixedly arranged on the lower surface of the second cover 6 for supplying power to the strain gauge 1, the vibration sensor 2, the wireless communication module 3, the gas measurement module 10 and the data storage module 11.

[0082] In a specific implementation, the power supply 12 can provide power for various modules such as data measurement, data storage, and data transmission, thereby providing a guarantee for determining the stability of the coal and rock mass around the borehole.

[0083] In the above-mentioned embodiment, the stability monitoring device is described as further comprising a power supply for continuously supplying power to each of the above modules. In another embodiment of the present invention, a coal rock mass stability monitoring system is described.

[0084] For example, the coal-rock stability monitoring system includes the aforementioned coal-rock stability monitoring device and an early warning platform disposed on the ground and connected to the coal-rock stability monitoring device.

[0085] Among them, the early warning platform is used to analyze the stability of the coal and rock mass around the drilling hole.

[0086] It should be noted that the connection between the stability monitoring device and the early warning platform is a communication connection, which can be, for example, a wireless communication method.

[0087] In a specific implementation, the wireless communication module 3 can instantly send the measured or stored data (for example, stress values ​​and vibration frequency values) to an early warning platform set up on the ground. The early warning platform can analyze the stability of the coal rock mass based on the above data and issue an early warning (for example, an alarm sound or an alarm light) when the coal rock mass is unstable.

[0088] The specific analysis process is as follows:

[0089] First, the early warning platform receives the stress values ​​σ0 and σ1 and the vibration frequency values ​​f0 and f1 twice (for example, before and after mining).

[0090] Second, calculate the stress ratio σ before and after mining x =σ0 / σ1, vibration frequency ratio f x =f0 / f1.

[0091] Third, if the vibration frequency ratio f x Less than or equal to the preset vibration frequency ratio f x0 , or stress ratio σ x Less than or equal to the preset stress ratio σ x0 , the coal rock mass is unstable; if the vibration frequency ratio f x Greater than the preset vibration frequency ratio f x0 , and the stress ratio σ x Greater than the preset stress ratio σ x0 , the coal rock mass is stable.

[0092] For example, if the preset vibration frequency ratio f x0 is 90%, the preset stress ratio σ x0 When it is 75%.

[0093] If f x =50% less than f x0 =90%, and σ x =30% less than σ x0 =75%, the coal rock mass is unstable.

[0094] Or, if f x =95% greater than f x0 =90%, and σ x =30% less than σ x0 =75%, the coal rock mass is also unstable.

[0095] Or, if f x =50% less than f x0 =90%, and σ x =80% greater than σ x0 =75%, the coal rock mass is also unstable.

[0096] That is, f x and σ x If either of the two conditions does not meet the preset conditions, the coal rock mass will be unstable.

[0097] On the contrary, if f x =95% greater than f x0 =90%, and σ x =80% greater than σ x0 =75%, the coal rock mass is stable. x0 and σ x0 The value of can be set according to actual conditions, and this embodiment is only used as an example.

[0098] In the embodiment described above, it is described how to use the vibration frequency ratio f x and the preset vibration frequency ratio f x0 , and the stress ratio σ x and the preset stress ratio σ x0 Monitoring whether the coal rock mass is stable. In another embodiment of the present invention, the instability levels of the coal rock mass are subdivided when the coal rock mass is unstable, the instability categories of each instability level, and the intervals corresponding to each instability category are introduced.

[0099] For example, the degree of coal rock instability includes mild instability, moderate instability, and severe instability;

[0100] Mild instability includes mild instability of vibration frequency and mild instability of stress value; when vibration frequency is slightly unstable, the vibration frequency ratio range is (f A , f B ], when the stress value is slightly unstable, the stress ratio range is (σ A ,σ B ], f A is the lower limit of the slightly unstable vibration frequency, f B is the upper limit of the slightly unstable vibration frequency, σ A is the lower limit of the stress value that is slightly unstable, σ B is the upper limit of the slightly unstable stress value, f B Equal to the preset vibration frequency ratio f x0 ,σ B Equal to the preset stress ratio σ x0 ;

[0101] Moderate instability includes moderate instability of vibration frequency and moderate instability of stress value. When the vibration frequency is moderately unstable, the vibration frequency ratio range is (f C , f D ], the stress ratio range when the stress value is moderately unstable is (σ C ,σ D ], f C is the lower limit of moderate instability of vibration frequency, f D is the upper limit of moderate instability of vibration frequency, σ C is the lower limit of moderate instability of stress value, σ D is the upper limit of moderate instability of stress value, f D Equal to the preset vibration frequency ratio f A ,σ D Equal to the preset stress ratio σ A ;

[0102] Severe instability includes severe instability of vibration frequency and severe instability of stress value. When the vibration frequency is severely unstable, the vibration frequency ratio range is (f E , f F ], when the stress value is severely unstable, the stress ratio range is (σ E ,σ F ], f E is the lower limit of severe instability of vibration frequency, f F is the upper limit of severe instability of vibration frequency, σ E is the lower limit of severe instability of stress value, σ F is the upper limit of severe instability of stress value, f F Equal to the preset vibration frequency ratio f C ,σ F Equal to the preset stress ratio σ C ;

[0103] Vibration frequency ratio f x The value range is (0, 100%], the stress value ratio σ x The value range is (0, 100%].

[0104] For example, (f A , f B ] can be (75%, 90%], (f C , f D ] can be (55%, 75%], (f E , f F ] can be (0, 55%], f x0 It can be 90%.

[0105] For example, (σ A ,σ B ] can be (55%, 75%], (f C , f D ] can be (35%, 55%], (f E , f F ] can be (0, 35%], f x0 It can be 75%.

[0106] The aforementioned embodiment describes the instability levels of coal-rock mass instability, the instability categories of each instability level, and the intervals corresponding to each instability category. Another embodiment of the present invention describes how the wireless communication module 3 can instantly transmit measured or stored data (e.g., gas concentration values) to an on-ground early warning platform. The early warning platform can analyze the stability of the coal-rock mass based on this data and issue an early warning (e.g., an alarm sound or an alarm light) when the coal-rock mass is unstable.

[0107] The analysis process is as follows:

[0108] First, the early warning platform receives the gas concentration value c1.

[0109] Second, determine whether the gas concentration value c1 is greater than or equal to the preset gas concentration value c0.

[0110] Third, if yes, issue an early warning; if no, continue monitoring.

[0111] It is understandable that when the above stress ratio, vibration frequency ratio or gas concentration value exceeds the preset range, the early warning platform can sound an alarm or turn on an alarm light so that the staff can stop the coal rock mining work in time.

[0112] In the aforementioned embodiment, the wireless communication module 3 can instantly transmit measured or stored data (e.g., gas concentration values) to an above-ground early warning platform. The early warning platform can then analyze the stability of the coal and rock mass based on this data and issue an early warning (e.g., an alarm sound or warning light) when the coal and rock mass becomes unstable. Another embodiment of the present invention describes the areas, locations, and number of stability monitoring devices placed within an underground coal and rock mass.

[0113] Figure 9 for Figure 1 Schematic diagram of the actual layout of the medium stability monitoring device in the coal rock mass, see Figure 9 , Figure 9 It is a cross-sectional view of the underground coal and rock mass (i.e., a view of the coal and rock layer at a certain depth underground after horizontal cutting). The figure includes three areas. The middle area is the working face (i.e., the coal body to be mined), and the areas at the upper and lower ends of the middle area are the working face return air chute (i.e., a tunnel-like roadway) and the working face transport chute (i.e., a tunnel-like roadway), and the goaf on the right side of the working face (i.e., the area where the coal body has been mined. After the coal body has been mined, the rock layer above the coal body collapses and fills the goaf). This pre-excavated roadway reaches the distance of the planned coal body. During formal mining, the series of processes involved in mining the coal body from the end of the roadway to the beginning is called mining.

[0114] Can be Figure 9 Stability monitoring devices are arranged at regular intervals (e.g., 10m) on the inner walls of the middle and upper tunnels, for example, Figure 1 The middle measuring point 1 is the location where the first stability monitoring device is arranged, followed by the inference point 2 and measuring point 3.

[0115] It should be noted that a certain depth can be dug at measuring point 1 so that multiple stability monitoring devices can be placed at different depths of measuring point 1 (separated by air bags). The stability monitoring devices at different depths of the same measuring point can measure the stability of the drilled coal rock mass at different depths, that is, a wider area can be monitored.

[0116] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A stability monitoring device for coal and rock mining, characterized by: include: A stress gauge (1) disposed in a coal-rock borehole for measuring the interaction force between the coal and rock around the borehole, a vibration sensor (2) disposed in the coal-rock borehole for measuring the vibration frequency of the coal-rock fracture around the borehole, a transmission module for transmitting the interaction force and the vibration frequency to the stress gauge (1) and the vibration sensor (2), and a fixing module disposed below the transmission module for fixing the stress gauge (1). The transmission module comprises a first cover (13) and three energy transmission components (4); the first cover (13) is provided with three positioning openings (5) at equal intervals of 120° on its circumferential surface; the three energy transmission components (4) are clamped in the positioning openings (5); The fixing module comprises a second cover (6), three fixing components (7) fixedly arranged above the second cover (6) for fixing the strain gauge (1), and a support component (8) fixedly arranged above the fixing component (7) for making the energy transfer component (4) rigidly contact the inner wall of the coal and rock borehole. The strain gauge (1) is fixedly arranged in a space surrounded by the three fixing components (7), and the vibration sensor (2) is fixedly arranged on the lower surface of the second cover (6).

2. The stability monitoring device for coal and rock mining according to claim 1, characterized in that: It also includes a wireless communication module (3) for transmitting the stress value measured by the stress gauge (1) and the vibration frequency value measured by the vibration sensor (2) to an early warning platform arranged on the ground in real time, and the wireless communication module (3) is fixedly arranged on the lower surface of the second cover (6).

3. The stability monitoring device for coal and rock mining according to claim 1, characterized in that: The energy transmission component (4) is an energy transmission pin, the fixing component (7) is a triangular plate, the spreading component (8) is a conical head, and the strain gauge (1) comprises an elastic body (1-1) for measuring the interaction force, and a strain gauge (1-2) fixedly connected to the elastic body (1-1) for measuring the deformation of the elastic body (1-1).

4. The stability monitoring device for coal and rock mining according to claim 2, characterized in that: It also includes a protective cover (9) fixedly arranged on the lower surface of the second cover (6) for protecting the lower surface components of the second cover (6), and a gas measurement module (10) fixedly arranged at the other end of the protective cover (9) for measuring the gas concentration value in the coal rock borehole.

5. The stability monitoring device for coal and rock mining according to claim 4, characterized in that: It also includes a data storage module (11) fixedly arranged on the lower surface of the second cover (6) and used to store the stress value, the vibration frequency value and the gas concentration value.

6. The stability monitoring device for coal and rock mining according to claim 5, characterized in that: It also includes a power supply (12) fixedly arranged on the lower surface of the second cover (6) for supplying power to the strain gauge (1), the vibration sensor (2), the wireless communication module (3), the gas measurement module (10) and the data storage module (11).

7. A stability monitoring system for coal and rock mining, characterized by: It comprises a coal-rock mining stability monitoring device as described in claim 6, and an early warning platform arranged on the ground and connected to the coal-rock mining stability monitoring device.

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