Stress and deformation integrated pillar stability monitoring device, system and method

Abstract

The present application belongs to the technical field of mine safety monitoring, and discloses a kind of pillar stability monitoring device, system and method integrated stress and deformation, monitoring module is used to detect and collect strain data and resistivity data using stress monitoring unit and resistivity monitoring unit;Central processing module is connected with monitoring module, placed in underground monitoring center, and directly connected with uphole monitoring center computer through optical fiber, for processing the data collected by monitoring module, and the processing result is transmitted through optical fiber and saved to the uphole monitoring center computer memory in real time;Uphole monitoring module is used to obtain the stress and resistivity change law curve of monitoring module under load, and to predict and warn according to the change law of both.The present application has the advantages of simple structure, low implementation difficulty and cost, strong adaptability, can greatly reduce the difficulty of pillar stability monitoring and improve the monitoring accuracy.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of mine safety monitoring, and particularly relates to a pillar stability monitoring device, system and method integrating stress and deformation. BACKGROUND

[0002] At present, in the process of mining recovery, a large number of pillars are often left to maintain the stability of the stope, which provides protection for the safety operation of the mine by bearing the force of the overburden rock load. As the mining continues, the stress state of the pillar also changes continuously, so the monitoring of the mechanical properties of the pillar is particularly important for the safety production of the mine. At the same time, as a certain amount of mineral resources are often contained in the left pillar, in order to improve the resource recovery rate of the mine and prolong the service life of the mine, the recovery of the pillar is gradually put on the agenda of each mining enterprise. The left pillar often coexists with the goaf, and how to ensure the self-stability of the pillar under the overburden rock or filling body to prevent the deformation and collapse of the goaf is a difficult problem to be solved in the recovery process. Based on the above two reasons, a feasible technical means must be used to monitor the stability of the pillar to ensure the safety of the mining operation in the process of stope recovery and pillar recovery.

[0003] At present, the stability of the pillar is mainly evaluated by monitoring the changes of the stress and strain of the pillar at home and abroad, and the main disadvantage of this method is that the stress and strain macroscopic parameters cannot effectively reflect the generation and development of the microcracks in the pillar, and the reflection on the mechanism of the pillar instability is weak. Therefore, some inventions try to achieve the purpose of monitoring the stability of the pillar by combining acoustic emission, ultrasonic wave and microseismic signal processing methods, and provide a basis for the failure mechanism of the pillar. However, whether it is acoustic emission, ultrasonic wave or microseismic signal, the influence of the surrounding noise is great, and in the monitoring process, corresponding means must be taken to isolate the noise, and the mine needs to be stopped for construction if necessary to eliminate the noise. If the long-term stability of the pillar is to be monitored, this method consumes a lot of manpower and material resources, and the cost is large. Therefore, the present application provides a method and system which is highly adaptable to the surrounding environment and has good monitoring effect, and is expected to achieve the goal of monitoring the mechanical properties of the pillar in the whole service process of the mine.

[0004] Through the above analysis, the problems and defects of the prior art are that the existing pillar stability monitoring method is greatly affected by the surrounding noise, and in the monitoring process, corresponding means must be taken to isolate the noise, which consumes a lot of manpower and material resources and has a large cost. SUMMARY

[0005] In view of the problems existing in the prior art, the present application provides a pillar stability monitoring device, system and method integrating stress and deformation.

[0006] The application is achieved by a stress and deformation integrated pillar stability monitoring system, which comprises:

[0007] A monitoring module is used for detecting and collecting strain data and resistivity data by the stress monitoring unit and the resistivity monitoring unit;

[0008] A central processing module is connected with the monitoring module, placed in the downhole monitoring center, and directly connected with the uphole monitoring center computer through an optical fiber, used for processing the data collected by the monitoring module, and transmitting the processing results to the uphole monitoring center computer memory through the optical fiber for real-time saving;

[0009] An uphole monitoring module is used for obtaining stress and resistivity change law curves of the monitoring module under the load, and making a prediction and early warning according to the change laws.

[0010] Further, the central processing module comprises:

[0011] A stress data processing unit is used for processing the stress information obtained by the monitoring module;

[0012] A resistivity data processing unit is used for processing the resistivity information obtained by the monitoring module;

[0013] An early warning unit is used for setting stress change and resistivity change thresholds, and releasing a danger signal when the stress change or the resistivity change reaches the set threshold.

[0014] Further, the stress and deformation integrated pillar stability monitoring system further comprises an uphole power module, which is used for converting alternating current into direct current, and providing direct current voltage for the central processing module and the monitoring module.

[0015] Another object of the application is to provide a stress and deformation integrated pillar stability monitoring method, which comprises:

[0016] Step one, the pillar is loaded between the goaf roof and the goaf floor, and a drill hole is arranged at a key weak position in the pillar;

[0017] Step two, an appropriate amount of cement mortar is filled in the drill hole, the monitoring module is loaded into the drill hole, the bottom of the monitoring main body is fully contacted with the cement mortar, and then the cement mortar is added to fill the gap between the drill hole and the monitoring module, so that the two are tightly coupled.

[0018] Step three, the monitoring module and the central processing module are connected through independent copper wire leads, the central processing module and the uphole monitoring center computer are connected through an optical fiber, the uphole power module is arranged in the uphole monitoring center, the uphole power module converts industrial alternating current into direct current, and provides power for the central processing module.

[0019] Step four, after the above steps are completed, enter the monitoring mode, the central processing module obtains the stress and resistivity change information collected by the monitoring module in real time, and the monitoring center on the well tracks the whole process of the stability of the pillar in real time.

[0020] Further, the drilling diameter in the step one is 50mm, the depth is 210mm, the drilling direction is upwardly offset by 2°-5°, and the number of drillings is arranged according to the size of the pillar and the danger degree thereof.

[0021] Further, the central processing module in the step four obtains the stress and resistivity change information collected by the monitoring module in real time, and the central processing module in the step four obtains the stress and resistivity change information collected by the monitoring module in real time.

[0022] The strain information received by the stress sensor is converted into stress information by the stress data processing unit, the stress monitoring is performed in real time, the stress data processing unit sets a time interval to collect the stress information, the time interval is set according to the actual requirement of the mine site, and finally a visual image is obtained;

[0023] The circular conductive grid is released by the resistivity data processing unit, and the current value passing through the monitoring body is obtained, according to Ohm's law, the resistance R of the monitoring body is calculated from the voltage and the current, and then the resistivity p of the monitoring body is obtained, and the resistivity calculation method is as follows:

[0024] p=RS / L

[0025] Wherein S is the cross-sectional area of the monitoring body, and L is the distance between two preset conductive grids in the monitoring body.

[0026] Another object of the present application is to provide a pillar stability monitoring device integrating stress and deformation, which comprises:

[0027] The stress and resistivity monitoring device, the central processing device and the power supply;

[0028] The central processing device is connected with the stress and resistivity monitoring device, and the power supply is connected with the stress and resistivity monitoring device and the central processing device respectively;

[0029] The stress and resistivity monitoring device is provided with a monitoring body, a stress sensor and a conductive grid, the monitoring body is made of water, cement, quartz sand and carbon fiber, two stress sensors are arranged along the side edge of the monitoring body, and the distance from the two ends of the body is 55mm, and two conductive grids are arranged inside the monitoring body, and the distance from the two ends of the body is 50mm;

[0030] Further, the stress sensor is circular ring-shaped, with an outer diameter of 50 mm and an inner diameter of 45 mm, and is composed of three layers of materials, the outer layer being a pressure-bearing matrix, the middle layer being a force-sensitive resistance foil, and the bottom layer being a rigid protective material, the force-sensitive resistance foil being connected to the stress data processing unit through copper wire leads;

[0031] The conductive grid is circular and is made of copper wires, with a diameter of 50 mm.

[0032] Further, the step of arranging the stress sensor and the conductive grid in the monitoring body includes:

[0033] First, the inner diameter of the pouring mold is 50 mm and the height is 200 mm, and the pouring mold is composed of a sensor fitting part, a hinge, a lock, a lead-out groove, and a twisted ring. Before pouring the monitoring body, the stress sensor and the conductive grid are placed in the fitting part of the pouring mold, then the two hinges of the pouring mold are closed, the mold lock is locked, the leads are placed in the lead-out groove and led out to the outside of the mold, and the mold is placed upright on a smooth plane.

[0034] Second, according to the mechanical parameters of the pillar rock core obtained by laboratory testing, such as uniaxial compressive strength, tensile strength, and Poisson's ratio, the proportions of water, cement, and quartz sand during the cementation process and the solid mass concentration are set, weighed, and poured into a concrete mixer for mixing.

[0035] Third, the mixed slurry is poured into the pouring mold, and the slurry is slightly higher than the mold to prevent the slurry from settling.

[0036] Fourth, after the pouring mold is placed for 12 hours, the excess slurry on the top is scraped off with a scraper, and then the mold is placed for another 24 hours. The mold lock is opened, and the monitoring body is taken out and placed in a curing box for 28 days to form a cylindrical rock-like material with a diameter of 50 mm and a length of 200 mm.

[0037] Further, the particle size of the quartz sand is 0.425-0.85 mm, and the solid mass concentration of the slurry is more than 70%. While stirring in the mixer, 10% of the cement content of carbon fibers is added to the mixed liquid to enhance the electrical conductivity of the monitoring body.

[0038] In combination with the above technical solutions and the technical problems solved, the technical solutions to be protected by the present application have the following advantages and positive effects:

[0039] First, in view of the technical problems existing in the above-mentioned prior art and the difficulty in solving the problems, the technical solutions to be protected by the present application are closely combined with the results and data obtained during the research and development process, and the technical problems solved by the technical solutions are analyzed in detail and deeply. Some creative technical effects brought about after solving the problems are described as follows:

[0040] The application has the advantages of simple structure of the monitoring device, low implementation difficulty and cost, and strong adaptability, and can greatly reduce the difficulty of the pillar stability monitoring and improve the monitoring accuracy.

[0041] The monitoring device has a simple structure: the main body of the monitoring device is made of cement and quartz sand, which are commonly used building materials in mines, and the monitoring purpose is achieved by adding stress sensors and conductive grids in the main body.

[0042] Low implementation difficulty and cost: the monitoring method provided by the application is mainly realized by using a handheld shallow hole rock drilling machine commonly used in mines, and the instrument is simple to install.

[0043] Strong adaptability: the pillar stability monitoring system based on the change rule of stress and resistivity of rock mass during loading is not affected by the surrounding environment noise, and does not need to provide a special environment for pillar monitoring.

[0044] Secondly, the technical scheme is regarded as a whole or from the perspective of the product, the technical effects and advantages of the technical scheme to be protected by the application are described as follows:

[0045] The monitoring method and system have low implementation difficulty, simple structure of the monitoring device, strong adaptability, and can greatly reduce the difficulty of the pillar stability monitoring and improve the monitoring accuracy.

[0046] The application monitors the pillar stability based on the change of stress and resistivity during loading of the pillar, and compared with the existing pillar stability monitoring methods such as microseism, ultrasonic wave or acoustic emission, the method and system are not affected by the surrounding environment noise, and the stress sensor and the resistivity sensor are integrated in the monitoring main body, which can collect the stress and resistivity information of the same position and same time of the pillar, and also saves the drilling cost of installing the sensor.

[0047] Thirdly, the creativity of the claims of the application is also reflected in the following important aspects:

[0048] The technical scheme of the application solves the technical problems that people have been eager to solve but have failed to succeed:

[0049] The existing pillar stability monitoring methods such as microseism, ultrasonic wave or acoustic emission are greatly affected by the surrounding noise, and in the monitoring process, corresponding means must be taken to isolate the noise, which consumes more manpower, material resources and has high cost. The present application is based on the stress and resistivity change of the pillar in the loading process, and proposes a method and system with low cost, strong adaptability to the surrounding environment and good monitoring effect, which is expected to realize the mechanical property monitoring target of the pillar in the whole service process of the mine. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 is the structural schematic diagram of the pillar stability monitoring device provided by the embodiment of the present application, which integrates stress and deformation;

[0051] Figure 2 is the arrangement schematic diagram of the stress sensor and the conductive grid provided by the embodiment of the present application;

[0052] Figure 3 is the structural schematic diagram of the stress sensor provided by the embodiment of the present application;

[0053] Figure 4 is the structural schematic diagram of the conductive grid provided by the embodiment of the present application;

[0054] Figure 5 is the structural schematic diagram of the pouring mold provided by the embodiment of the present application;

[0055] Figure 6 is the installation schematic diagram of the stress and resistivity monitoring device in the pillar provided by the embodiment of the present application;

[0056] Figure 7 is the monitoring effect diagram in the monitoring main body room provided by the embodiment of the present application;

[0057] Figure 8 is the structural schematic diagram of the pillar stability monitoring system provided by the embodiment of the present application, which integrates stress and deformation.

[0058] In the figure: 1, monitoring main body; 2, stress sensor; 3, conductive grid; 4, pressure bearing base; 5, force sensitive resistance foil; 6, rigid protective material; 7, sensor embedding position; 8, hinge; 9, lock catch; 10, lead wire leading-out groove; 11, twisted ring; 12, goaf roof; 13, pillar; 14, goaf floor. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the present application will be further described in detail below with examples. It should be understood that the specific examples described here are only used to explain the present application, and are not used to limit the present application.

[0060] As Figures 1 to 4As shown in the figure, the pillar stability monitoring device integrating stress and deformation provided in this embodiment of the invention mainly consists of three parts: a stress and resistivity monitoring device, a central processing device, and a power supply.

[0061] The stress and resistivity monitoring device consists of a monitoring body 1, a stress sensor 2, and a conductive grid 3.

[0062] The monitoring body 1, constructed from water, cement, quartz sand, and carbon fiber, transmits the load borne by the pillar. The stress sensor 2 and conductive mesh 3 receive information about the stress on the monitoring body and the change in resistivity under this stress. Two circular stress sensors are arranged along the side edge of the monitoring body, each 55mm from both ends. Two circular conductive meshes are arranged inside the monitoring body, each 50mm from both ends.

[0063] Circular Stress Sensor: In this invention, the circular stress sensor has an outer diameter of 50mm and an inner diameter of 45mm. It consists of three layers: an outer pressure-bearing substrate 4, a middle force-sensitive resistor foil 5, and a bottom rigid protective material 6. The force-sensitive resistor foil and the stress data processing unit are connected via copper wire leads. The force-sensitive resistor foil converts the strain information of the pressure-bearing substrate into an electrical signal, which is then transmitted in real-time to the ground monitoring room for monitoring purposes.

[0064] Circular conductive grid: In this invention, the circular conductive grid is made of copper metal wire with a diameter of 50mm and has good conductivity. A DC voltage is released to the circular conductive grid through the resistivity data processing unit, and the current value passing through the monitoring body is obtained. By monitoring the change of this current value, the resistivity change information of the monitoring body can be obtained, thereby achieving the purpose of monitoring the stability of the ore pillar.

[0065] The steps for casting the monitoring body 1 and arranging the stress sensor 2 and conductive mesh 3 in this embodiment of the invention are as follows:

[0066] First, such as Figure 5 As shown, the casting mold has an inner diameter of 50mm and a height of 200mm. It consists of a sensor fitting 7, a hinge 8, a locking buckle 9, a lead wire guide groove 10, and a hinge ring 11. Before the main body is cast, the stress sensor and the conductive mesh are placed in the fitting 7 in the casting mold. Then, the two hinges 8 of the casting mold are closed, and the mold locking buckle 9 is locked. The lead wire is placed in the lead wire guide groove 10 and led out to the outside of the mold. The mold is then placed upright on a smooth surface.

[0067] Secondly, based on the mechanical parameters such as uniaxial compressive strength, tensile strength, and Poisson's ratio of the rock core obtained from laboratory tests, the proportions and solid mass concentrations of water, cement, and quartz sand during the cementing process were set, weighed, and poured into a concrete mixer for uniform mixing. It is worth noting that, to ensure the strength of the monitoring substrate matches the rock mass, the quartz sand particle size should be controlled between 0.425-0.85 mm, and the slurry solid mass concentration should be controlled above 70%. Simultaneously, carbon fiber with 10% cement content was added to the mixture to enhance the conductivity of the monitoring substrate.

[0068] Third, pour the well-mixed slurry into the casting mold, making sure the slurry is slightly higher than the mold to prevent it from settling.

[0069] Fourth, after the mold has been poured, let it stand for 12 hours, then use a scraper to remove the excess slurry from the top. Let it stand for another 24 hours, then open the mold lock, take out the monitoring body, and then put it in a curing box for 28 days to finally form a cylindrical rock-like material with a diameter of 50mm and a length of 200mm.

[0070] The central processing unit comprises a stress data processing unit, a resistivity data processing unit, and an early warning unit, all integrated within the central processing module. This unit is located in the downhole monitoring center and directly connected to the surface monitoring center computer via fiber optic cable. The surface monitoring center computer is equipped with control software. By inputting corresponding commands into the software, the system can obtain the stress and resistivity change curves of the monitored object under load, and generate forecasts and early warnings based on these patterns. All this information is transmitted in real-time via fiber optic cable and stored in the surface monitoring center computer's memory.

[0071] The power supply is located in the well monitoring center. Its function is to convert AC power into DC power to provide DC voltage for the central processing module and monitoring module.

[0072] The pillar stability monitoring method integrating stress and deformation provided in this invention mainly includes the following steps:

[0073] Step 1, as follows Figure 6 As shown, the pillar 13 is supported between the goaf roof 12 and the goaf floor 14. Holes are drilled at key weak points in the pillar. The diameter of the holes is 50 mm and the depth is 210 mm. The drilling direction can be offset upward by 2°-5° to avoid water accumulation inside affecting the resistivity monitoring effect. The number of holes is arranged according to the size of the pillar and its degree of danger.

[0074] Step 2: First, fill the borehole with an appropriate amount of cement mortar, then install the monitoring module into the borehole. After the bottom of the monitoring module is in full contact with the cement mortar, add more cement mortar to fill the gap between the borehole and the monitoring module, so that the two are tightly coupled.

[0075] Step three, through each independent copper wire lead connection monitoring module and downhole central processing module, using optical fiber connection downhole central processing module and computer in the monitoring room, the monitoring room is arranged with power module, power module can convert industrial AC into DC, power module is responsible for providing power for the central processing module.

[0076] Step four, after the above steps can enter the monitoring mode, the central processing module real-time acquisition, get the information of the pillar stress and resistivity change, monitoring personnel can be in the monitoring center in the mine column stability of the whole process in real time tracking.

[0077] As shown in Figure 8 The pillar stability monitoring system provided by the embodiment of the application mainly includes a monitoring module, a central processing module and an uphole monitoring module.

[0078] The monitoring module includes a stress monitoring unit and a resistivity monitoring unit.

[0079] The central processing module is integrated with a stress data processing unit, a resistivity data processing unit and a warning unit, the stress data processing unit and the resistivity data processing unit can process the stress information and the resistivity information obtained by the monitoring module, and the warning unit can set stress change and resistivity change thresholds, when the stress change or the resistivity change reaches the set threshold, the warning unit will release a danger signal, according to the danger signal, the mine can take corresponding safety measures, so as to realize the purpose of pillar stability monitoring and mine safety production.

[0080] The stress monitoring unit realizes the conversion of the strain information received by the stress sensor into stress information through the stress data processing unit, the stress monitoring is real-time, the stress data processing unit can set a time interval to collect the stress information, the time interval is set according to the actual requirements of the mine site, and finally a visual image is obtained. The resistivity data processing unit can also collect and obtain a resistivity change visual image in real time, and the specific operation process is as follows: the resistivity data processing unit releases a direct current voltage to the circular conductive grid, and obtains the current value passing through the monitoring subject, according to Ohm's law, the resistance R of the monitoring subject is calculated from the voltage and the current, and then the resistivity p of the monitoring subject is obtained, the resistivity calculation method is as formula (1), wherein S is the cross-sectional area of the monitoring subject, and L is the distance between two preset conductive grids in the monitoring subject.

[0081] p = RS / L (1)

[0082] The monitoring method and system of the application have low implementation difficulty, the monitoring device has simple structure and strong adaptability, and can greatly reduce the difficulty of pillar stability monitoring and improve the monitoring accuracy.

[0083] In order to prove the creativity and technical value of the technical solutions of the present application, this part is the application embodiment of the technical solutions of the claims on specific products or related technologies.

[0084] The pillar stability monitoring device, system and method provided by the embodiment of the present application can be used for monitoring the pillars in the mining process of the mine.

[0085] In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are only for description purposes and cannot be understood as indicating or implying relative importance.

[0086] It should be noted that the embodiments of the present application can be realized by hardware, software or a combination of software and hardware. The hardware part can be realized by using special logic; the software part can be stored in a memory and executed by a suitable instruction execution system, such as a microprocessor or a specially designed hardware. Those skilled in the art can understand that the above-mentioned devices and methods can be realized by using computer executable instructions and / or included in processor control code, such as provided on a carrier medium, such as a magnetic disk, CD or DVD-ROM, a programmable memory, such as a read-only memory (firmware), or a data carrier, such as an optical or electronic signal carrier. The devices of the present application and their modules can be realized by hardware circuits, such as very large scale integrated circuits or gate arrays, semiconductors, such as logic chips, transistors, or programmable hardware devices, such as field programmable gate arrays, programmable logic devices, etc. They can also be realized by software executed by various types of processors, or by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0087] As Figure 7 As shown in the above monitoring body, a uniaxial compression test was carried out in a laboratory, and the stress and resistivity change with time were obtained. It can be seen that with the advancement of monitoring time, the resistivity change curve of the monitoring body shows a trend of gradually rising first and then rapidly falling, and there are two obvious inflection points in the rising process, of which inflection point 1 appears before the stress peak, and inflection point 2 is basically the same as the stress peak σ cThe stress corresponding to the inflection point 1 is called sigma 1 in the application, and the stress is taken as a warning stress, so that the mine can take corresponding protection measures in advance according to the inflection point of the resistivity change before the peak stress arrives, and the occurrence of safety accidents is avoided.

[0088] The above is only a specific embodiment of the application, but the protection scope of the application is not limited thereto, any modification, equivalent replacement and improvement within the technical range disclosed by the application and within the spirit and principle of the application should be covered within the protection scope of the application.

Claims

1. A pillar stability monitoring system integrating stress and deformation monitoring, characterized in that, The stress and deformation integrated pillar stability monitoring system comprises: a monitoring module for detecting and collecting strain data and resistivity data by using a stress monitoring unit and a resistivity monitoring unit; a central processing module connected with the monitoring module, placed in a downhole monitoring center, and directly connected with an uphole monitoring center computer through an optical fiber, for processing data collected by the monitoring module and transmitting the processing results to the uphole monitoring center computer memory through the optical fiber for real-time saving; an uphole monitoring module for obtaining stress and resistivity change law curves of the monitoring module under load and making a prediction and early warning according to the change laws; the stress monitoring unit and the resistivity monitoring unit are provided with a monitoring body, a stress sensor and a conductive grid, the monitoring body is made of water, cement, quartz sand and carbon fiber, two stress sensors are arranged along the side edges of the monitoring body, and the distances from the two stress sensors to the ends of the monitoring body are both 55 mm, and two conductive grids are arranged inside the monitoring body, and the distances from the two conductive grids to the ends of the monitoring body are both 50 mm; the stress sensor is circular, with an outer diameter of 50 mm and an inner diameter of 45 mm, and is composed of three layers of materials, the outer part is a pressure bearing base, the middle part is a force sensitive resistance foil, and the bottom part is a rigid protective material, the force sensitive resistance foil is connected with a stress data processing unit through a copper wire lead; the conductive grid is circular and is made of copper wire, with a diameter of 50 mm; the central processing module comprises: a stress data processing unit for processing stress information obtained by the monitoring module; a resistivity data processing unit for processing resistivity information obtained by the monitoring module; an early warning unit for setting stress change and resistivity change thresholds, and releasing a danger signal when the stress change or the resistivity change reaches the set threshold; and further comprises an uphole power module for converting alternating current into direct current to provide direct current voltage for the central processing module and the monitoring module.

2. A stress and deformation integrated pillar stability monitoring method for implementing the stress and deformation integrated pillar stability monitoring system of claim 1, characterized by, The stress and deformation integrated pillar stability monitoring method comprises: Step one, a drill hole is made at a key weak position in a pillar between a goaf roof and a goaf floor; Step two, an appropriate amount of cement mortar is first filled into the drill hole, a monitoring module is then loaded into the drill hole, the bottom of the monitoring body is brought into full contact with the cement mortar, and then the cement mortar is added to fill the gap between the drill hole and the monitoring module, so that the two are tightly coupled; Step three, the monitoring module and the central processing module are connected through independent copper wire leads, the central processing module and an uphole monitoring center computer are connected using an optical fiber, an uphole power module is arranged in the uphole monitoring center, the uphole power module converts industrial alternating current into direct current to provide power for the central processing module; Step four, after the above steps are completed, the monitoring mode is entered, the central processing module obtains pillar stress and resistivity change information collected by the monitoring module in real time, and the uphole monitoring center tracks the whole process of pillar stability in real time.

3. The stress and deformation integrated pillar stability monitoring method of claim 2, wherein, The drill hole in step one has a diameter of 50 mm and a depth of 210 mm, the drill hole direction is upwardly offset by 2°~5°, and the number of drill holes is arranged according to the size of the pillar and the danger degree thereof.

4. The stress and deformation integrated pillar stability monitoring method of claim 2, wherein, The step four central processing module acquires the information of the pillar stress and resistivity changes collected by the monitoring module in real time, and the step four central processing module includes: The stress sensor receives the strain information which is converted into stress information by the stress data processing unit, and the stress monitoring is performed in real time; the stress data processing unit sets a time interval to collect the stress information, and the time interval is set according to the actual requirements of the mine site; finally, a visual image is obtained; The resistivity data processing unit releases a direct current voltage to the circular conductive grid, and obtains the current value through the monitoring body; according to Ohm's law, the resistance R of the monitoring body is calculated from the voltage and the current, and then the resistivity p of the monitoring body is obtained; the resistivity calculation method is as follows: ； Where S is the cross-sectional area of the monitoring body, and L is the distance between the two preset conductive grids in the monitoring body.

5. A stress and deformation integrated pillar stability monitoring device for implementing the stress and deformation integrated pillar stability monitoring system of claim 1, characterized by, The pillar stability monitoring device integrating stress and deformation includes: A stress and resistivity monitoring device, a central processing device and a power supply; The central processing device is connected with the stress and resistivity monitoring device, and the power supply is connected with the stress and resistivity monitoring device and the central processing device respectively; The stress and resistivity monitoring device is provided with a monitoring body, a stress sensor and a conductive grid; the monitoring body is made of water, cement, quartz sand and carbon fiber; two stress sensors are arranged along the side edge of the monitoring body, and the distance from the two stress sensors to the two ends of the monitoring body is 55 mm; two conductive grids are arranged inside the monitoring body, and the distance from the two conductive grids to the two ends of the monitoring body is 50 mm.

6. The stress and deformation integrated pillar stability monitoring device of claim 5, wherein, The stress sensor is circular, with an outer diameter of 50 mm and an inner diameter of 45 mm; it is composed of three layers of materials, the outer part is a pressure bearing matrix, the middle part is a force sensitive resistance foil, and the bottom part is a rigid protective material; the force sensitive resistance foil is connected with the stress data processing unit through a copper wire lead; The conductive grid is circular and made of copper wire, with a diameter of 50 mm.

7. The stress and deformation integrated pillar stability monitoring device of claim 5, wherein, The monitoring body and the arrangement of the stress sensor and the conductive grid include the following steps: First, the inner diameter of the pouring mold is 50 mm, and the height is 200 mm; it is composed of a sensor fitting place, a hinge, a lock, a lead-out groove and a twisted ring; before pouring the monitoring body, the stress sensor and the conductive grid are placed in the fitting place in the pouring mold, then the two hinges of the pouring mold are closed, the mold lock is locked, the lead is placed in the lead-out groove and led out to the outside of the mold, and the mold is placed vertically on a smooth plane; Second, according to the uniaxial compressive strength, tensile strength and Poisson's ratio mechanical parameters of the pillar rock core obtained by laboratory test, the proportion among water, cement and quartz sand and the solid mass concentration during the cementation process are set, weighed and poured into a concrete mixer for mixing; Third, the mixed slurry is poured into the pouring mold, and the slurry is slightly higher than the mold to prevent the slurry from settling; Fourth, after the pouring mold is placed for 12 hours, the excess slurry on the top is scraped off with a scraper, and then it is placed for another 24 hours; the mold lock is opened, and the monitoring body is taken out; then it is placed in a curing box for curing for 28 days, and finally a cylindrical rock-like material with a diameter of 50 mm and a length of 200 mm is formed.

8. The stress and deformation integrated pillar stability monitoring device of claim 7, wherein, The quartz sand has a particle size of 0.425-0.85 mm, and the solid mass concentration of the slurry is above 70%; while the slurry is stirred, 10% cement content carbon fibers are added into the mixture to enhance the conductivity of the monitoring body.

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