Rock mass stability evaluation method and system based on crustal stress measurement

Abstract

The invention relates to the technical field of stress measurement, and particularly discloses a rock mass stability evaluation method and system based on crustal stress measurement, which comprises the following steps: firstly, acquiring initial characteristic data of a rock mass, evaluating initial tensile strength, secondly, injecting liquid by using a hydraulic fracturing method, pressurizing, extracting real-time tensile strength, and comparing the initial tensile strength with the real-time tensile strength. Judging whether the pressure measurement process needs to be corrected or not, and monitoring the pressure change borne by the rock mass in real time; and starting receiving gain compensation, correcting a monitoring state and extracting data synchronously in a second measurement period when the rock mass pressure drops suddenly, and finally, constructing a pressure-time change relation graph according to the monitoring data, obtaining a ground stress value and uploading the ground stress value to a display port for evaluating the rock mass stability.

Description

Technical Field

[0001] The present invention relates to the technical field of stress measurement, and in particular to a rock mass stability assessment method and system based on ground stress measurement. Background Art

[0002] Rock mass is a complex geological medium, and its mechanical properties are affected by many factors, such as rock type, distribution of structural planes, groundwater effects, and ground stress state. Traditional rock mass stability assessment methods are mainly based on rock mechanics tests and empirical formulas. Although these methods can analyze rock mass stability to a certain extent, they often ignore the important factor of ground stress. Ground stress is the comprehensive result of various stresses that rock mass is subjected to during its formation and evolution, and it has an important control effect on the deformation and failure mechanism of rock mass.

[0003] For example, the invention patent with announcement number CN106768496B announces a rock stability evaluation method based on the stress state of the mining site, which belongs to the technical field of rock stability evaluation. The method includes the steps of original rock stress field measurement, mining stress field monitoring, comprehensive stress field calculation, rock mechanical property testing and rock relative stress state characterization. By comparing with the ultimate stress strength obtained in the laboratory, the relative stress state of the rock is calculated to judge the rock stability.

[0004] For example, the invention patent with the announcement number CN115014588B announces the detection system, method, electronic device and storage medium of rock stress. The rock stress detection system includes: a stress sensor and an energy storage device, wherein the stress sensor is connected to the energy storage device, wherein the stress sensor is used to generate an alternating current and an induced magnetic field according to the rock stress in response to the detection of rock stress, and provide the alternating current to the energy storage device; the energy storage device is used to store electrical energy and convert the alternating current into a direct current and provide it to the stress sensor; the stress sensor is also used to generate a Hall voltage under the action of the direct current and the induced magnetic field; wherein the Hall voltage is used to obtain the stress value of the rock stress.

[0005] Combining the above technical solutions, it is found that most of the existing rock stability assessment solutions rely on specific stress detection equipment and a single stress field superposition. Since rock stability will be affected by many factors and the rock area conditions are complex and changeable, the adaptability and flexibility of the rock stability assessment process will be reduced, resulting in poor accuracy of rock monitoring data, which ultimately affects the rock stability assessment. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a rock stability assessment method and system based on ground stress measurement, which can effectively solve the problems involved in the above-mentioned background technology.

[0007] To achieve the above objectives, the present invention is realized through the following technical solutions: In the first aspect of the present invention, a method for evaluating the stability of rock masses based on in-situ stress measurement is provided, including: collecting initial characteristic data of a rock mass area and determining an initial tensile strength evaluation value of the rock mass area; injecting liquid into the rock mass area and pressurizing it during a first measurement period based on the hydraulic fracturing method, and simultaneously extracting a real-time tensile strength evaluation value of the rock mass area during the first measurement period; determining whether to correct the pressure measurement process according to the initial tensile strength evaluation value of the rock mass area and the real-time tensile strength evaluation value of the rock mass area, and real-time monitoring of the pressure change borne by the rock mass area through a pressure sensing device; during a second measurement period, extracting the pressure monitoring data borne by the rock mass area, and starting a receive gain compensation operation at the time point when the pressure borne by the rock mass area drops suddenly to correct the monitoring state of the pressure sensing device and extracting the monitoring data of the pressure sensing device; constructing a change relationship graph between pressure and time according to the monitoring data of the pressure sensing device, finally obtaining the in-situ stress value of the rock mass, and uploading it to a preset display port for evaluating the stability of the rock mass.

[0008] As a further method, the process of determining the initial tensile strength evaluation value of the rock mass area is as follows: The initial characteristic data of the rock mass area includes the rock mass elastic modulus of the rock mass area, the rock Poisson's ratio of the rock mass area, the rock hardness of the rock mass area, and the rock density of the rock mass area; the rock mass elastic modulus of the rock mass area, the rock Poisson's ratio of the rock mass area, the rock hardness of the rock mass area, and the rock density of the rock mass area are respectively normalized to obtain the normalization results, and weighted aggregation processing is performed in sequence to obtain the initial tensile strength evaluation value of the rock mass area.

[0009] As a further method, the process of injecting liquid into the rock mass area and pressurizing it is as follows: According to the initial tensile strength evaluation value of the rock mass area, the initial pumping pressure and the initial pumping rate are matched. Based on the hydraulic fracturing method, during the first measurement period, the liquid is injected into the rock mass and pressurized through the initial pumping pressure and the initial pumping rate; the process of matching the initial pumping pressure and the initial pumping rate is specifically to match the initial tensile strength evaluation value of the rock mass area with the initial pumping pressures corresponding to the predefined initial tensile strength evaluation value intervals to determine the specific interval of the initial tensile strength evaluation value of the rock mass area and obtain the initial pumping pressure corresponding to this interval; the initial tensile strength evaluation value of the rock mass area is matched with the initial pumping rates corresponding to the predefined initial tensile strength evaluation value intervals to determine the specific interval of the initial tensile strength evaluation value of the rock mass area and obtain the initial pumping rate corresponding to this interval.

[0010] As a further method, a pressure measurement process correction is performed. The specific implementation process is as follows: If the tensile strength deviation in the rock mass area belongs to the first tensile deviation interval, the tensile strength verification result is determined as the first tensile strength verification result. According to the tensile strength deviation in the rock mass area, a ratio processing is carried out with the first tensile deviation interval to obtain the first deviation ratio of the tensile strength in the rock mass area. The pump injection adjustment pressure is matched and added to the initial pump injection pressure to obtain the pump injection adaptation pressure. At the same time, the real-time permeability of the rock mass area is extracted, and a ratio processing is carried out with the predefined reference permeability to obtain the permeability deviation degree value of the rock mass area. The pump injection rate adjustment coefficient is matched and multiplied by the initial pump injection rate to obtain the pump injection adaptation rate. In the second measurement period, the rock mass is injected with liquid and pressurized with the pump injection adaptation pressure and the pump injection adaptation rate, and the change in the pressure borne by the rock mass area is monitored in real time through a pressure sensing device. If the tensile strength deviation in the rock mass area belongs to the third tensile deviation interval, the tensile strength verification result is determined as the third tensile strength verification result. According to the tensile strength deviation in the rock mass area, a ratio processing is carried out with the third tensile deviation interval to obtain the second deviation ratio of the tensile strength in the rock mass area. The pump injection adjustment pressure is matched and subtracted from the initial pump injection pressure to obtain the pump injection adaptation pressure. At the same time, the real-time permeability of the rock mass area is extracted, and a ratio processing is carried out with the predefined reference permeability to obtain the permeability deviation degree value of the rock mass area. The pump injection rate adjustment coefficient is matched and multiplied by the initial pump injection rate to obtain the pump injection adaptation rate. In the second measurement period, the rock mass is injected with liquid and pressurized with the pump injection adaptation pressure and the pump injection adaptation rate, and the change in the pressure borne by the rock mass area is monitored in real time through a pressure sensing device.

[0011] As a further method, the monitoring state of the pressure sensing device is corrected. The specific correction process is as follows: During the second measurement period, the pressure monitoring data of the rock mass area borne by the pressure sensing device is extracted. At the time point when the pressure borne by the rock mass area drops suddenly, the reception gain compensation operation is started. The specific operation process is as follows: The real-time reception gain value of the pressure sensing device is extracted and added to the preset gain compensation value to obtain the reception gain correction value of the pressure sensing device. The operation data of the pressure sensing device is collected in real time, and the operation quality index of the pressure sensing device is evaluated and compared with the predefined operation quality adaptation index. If the operation quality index of the pressure sensing device is greater than or equal to the operation quality adaptation index, the monitoring of the change in the pressure borne by the rock mass area is maintained. If the operation quality index of the pressure sensing device is less than the operation quality adaptation index, the difference between the operation quality index of the pressure sensing device and the operation quality adaptation index is processed to obtain the operation quality deviation of the pressure sensing device. The gain compensation coefficient is matched and multiplied by the reception gain correction value of the pressure sensing device to obtain the reception gain adaptation value of the pressure sensing device, and the reception gain of the pressure sensing device is configured to complete the correction of the effective signal of the pressure sensing device.

[0012] As a further method, the in-situ stress value of the rock mass is finally obtained. The specific analysis process is as follows: According to the monitoring data of the pressure sensing device, a variation relationship diagram between pressure and time is constructed, and the fracture pressure of the rock mass area and the closure pressure of the rock mass area are extracted from the variation relationship diagram between pressure and time; According to the stress-strain relationship formula, the fracture pressure of the rock mass area and the closure pressure of the rock mass area are substituted into the formula based on elastic mechanics and fracture mechanics to deduce the in-situ stress value of the rock mass.

[0013] The second aspect of the present invention provides a rock mass stability evaluation system based on in-situ stress measurement, including: an initial tensile strength evaluation module for collecting initial characteristic data of the rock mass area and determining the initial tensile strength evaluation value of the rock mass area; a real-time tensile strength prediction module for injecting liquid and pressurizing the rock mass area during a first measurement period based on the hydraulic fracturing method, and extracting the real-time tensile strength evaluation value of the rock mass area during the first measurement period; a pressure measurement process correction module for determining whether to correct the pressure measurement process according to the initial tensile strength evaluation value of the rock mass area and the real-time tensile strength evaluation value of the rock mass area, and monitoring the change in the pressure borne by the rock mass area in real time through a pressure sensing device; a device monitoring state correction module for extracting the pressure monitoring data of the rock mass area during a second measurement period, and starting the receive gain compensation operation at the time point when the pressure borne by the rock mass area drops suddenly to correct the monitoring state of the pressure sensing device and extract the monitoring data of the pressure sensing device; an in-situ stress analysis and upload module for constructing a variation relationship diagram between pressure and time according to the monitoring data of the pressure sensing device, finally obtaining the in-situ stress value of the rock mass, and uploading it to a preset display port for rock mass stability evaluation.

[0014] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) By providing a rock mass stability evaluation method and system based on in-situ stress measurement, the present invention first collects the initial characteristic data of the rock mass and evaluates the initial tensile strength. Secondly, the hydraulic fracturing method is used to inject liquid and pressurize, and the real-time tensile strength is extracted. The initial and real-time tensile strengths are compared to determine whether the pressure measurement process needs to be corrected, and at the same time, the change in the pressure borne by the rock mass is monitored in real time; Synchronously, during the second measurement period, when the rock mass pressure drops suddenly, the receive gain compensation is started to correct the monitoring state and extract the data. Finally, according to the monitoring data, a pressure-time variation relationship diagram is constructed, the in-situ stress value is obtained and uploaded to the display port for evaluating the rock mass stability.

[0015] (2) By collecting the initial characteristic data of the rock mass area and determining the initial tensile strength evaluation value, the present invention can make the in-situ stress measurement more targeted, optimize the in-situ stress measurement process, and improve the implementation efficiency of the in-situ stress measurement. At the same time, by matching the initial measurement parameters according to the initial tensile strength evaluation value, the rock mass structure can be protected, preventing rupture caused by insufficient initial tensile strength and maintaining the stability of the rock mass. In addition, it can also provide basic data for subsequent stability evaluation, improve the evaluation accuracy, and enhance the safety and reliability of the measurement process.

[0016] (3) By collecting the operation data of the pressure sensing device in real time and evaluating the operation quality index, the present invention helps to improve the reliability of the monitoring data of the pressure sensing device and reduce the error source of the measurement time. At the same time, evaluating the operation quality of the pressure sensing device helps to protect the device, prevent damage to the device due to abnormal signal strength, and extend the service life. By ensuring the data quality, the stability of the rock mass can be evaluated more accurately, and the credibility of the evaluation result can be improved. In addition, real-time evaluation can enhance the adaptability of the method, flexibly respond to different geological conditions and environmental changes, and improve the flexibility and reliability of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described with reference to the accompanying drawings. However, the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the following drawings without creative efforts.

[0018] Figure 1 It is a schematic flowchart of the method steps of the present invention; Figure 2 It is a schematic diagram of the system module connection of the present invention; Figure 3 It is a pressure-time change curve; Figure 4 It is a flowchart of the pressure measurement determination and correction; Figure 5 It is a flowchart of the monitoring status determination and correction. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0020] Referring to Figure 1 As shown, the first aspect of the present invention provides a method for evaluating the stability of a rock mass based on in-situ stress measurement, including: collecting the initial characteristic data of the rock mass area and determining the initial tensile strength evaluation value of the rock mass area.

[0021] Specifically, the process for determining the initial tensile strength evaluation value of the rock mass area is as follows: The initial characteristic data of the rock mass area include the elastic modulus of the rock mass in the rock mass area, the Poisson's ratio of the rock in the rock mass area, the hardness of the rock mass in the rock mass area, and the density of the rock mass in the rock mass area. Among them, the elastic modulus of the rock mass and the Poisson's ratio of the rock can be obtained through in-situ tests on-site (such as acoustic wave tests), the hardness of the rock mass can be measured with a hardness tester, and the density of the rock mass can be measured with a densitometer.

[0022] Normalize the elastic modulus of the rock mass in the rock mass area, the Poisson's ratio of the rock in the rock mass area, the hardness of the rock mass in the rock mass area, and the density of the rock mass in the rock mass area respectively to obtain the normalization results, and then perform weighted aggregation processing in sequence to obtain the initial tensile strength evaluation value of the rock mass area. The specific analysis process is as follows: , In the formula, is the initial tensile strength evaluation value of the rock mass area, E is the initial tensile strength evaluation value of the rock mass area, is the normalized value of the Poisson's ratio of the rock in the rock mass area, R is the normalized value of the hardness of the rock mass in the rock mass area, WH is the normalized value of the density of the rock mass in the rock mass area, is the weight element corresponding to the elastic modulus of the rock mass predefined in the rock mass state management library, is the weight element corresponding to the Poisson's ratio of the rock predefined in the rock mass state management library, is the weight element corresponding to the hardness of the rock mass predefined in the rock mass state management library, is the weight element corresponding to the density of the rock mass predefined in the rock mass state management library.

[0023] It should be explained that the above-mentioned elastic modulus of the rock mass refers to the index of the ratio of stress to strain in the elastic deformation stage of the rock mass; the Poisson's ratio of the rock refers to the index of the ratio of transverse strain to longitudinal strain in the elastic deformation stage of the rock mass.

[0024] Among them, the weight element corresponding to the rock elastic modulus, the weight element corresponding to the rock Poisson's ratio, the weight element corresponding to the rock hardness and the weight element corresponding to the rock density are all extracted from the rock state management library, and the mapping relationship can be a one-to-one correspondence or a many-to-one relationship. For example, the rock elastic modulus, the rock Poisson's ratio, the rock hardness and the rock density are respectively mapped with the weight element corresponding to the rock elastic modulus, the weight element corresponding to the rock Poisson's ratio, the weight element corresponding to the rock hardness and the weight element corresponding to the rock density preset in the rock state management library to form a mapping set. The real-time rock elastic modulus, rock Poisson's ratio, rock hardness and rock density are brought into the mapping set to obtain the weight element corresponding to the rock elastic modulus, the weight element corresponding to the rock Poisson's ratio, the weight element corresponding to the rock hardness and the weight element corresponding to the rock density.

[0025] In this embodiment, through the multivariate analysis of rock elastic modulus, rock Poisson's ratio, rock hardness and rock density, the correlation between these parameters is specifically considered. Under normal circumstances, the rock mass with a higher elastic modulus has a lower Poisson's ratio. This is because the internal structure of the rock mass with a high elastic modulus is denser, the intermolecular force is stronger, and it is not easy to deform laterally when subjected to force. Therefore, the Poisson's ratio is lower, and the initial tensile strength of the rock mass area is larger. Similarly, the rock mass with a higher density has a lower Poisson's ratio. This is because the internal structure of the rock mass with a higher density is denser, the intermolecular force is stronger, and it is not easy to deform laterally when subjected to force. The initial tensile strength of the rock mass area is also larger. The elastic modulus and hardness are usually positively correlated. Rock masses with high elastic modulus usually have higher hardness because they both reflect the rigidity and ability to resist deformation of the rock mass. The rock mass with a higher density usually has a denser internal structure and stronger intermolecular force, so the hardness is higher and the initial tensile strength is greater.

[0026] Based on the hydraulic fracturing method, liquid is injected into the rock mass area and pressurized during the first measurement period, and at the same time, a real-time tensile strength evaluation value of the rock mass area is extracted during the first measurement period.

[0027] The above-mentioned hydraulic fracturing method, the specific implementation process is as follows: First, it is necessary to drill a hole in the rock mass area where the in-situ stress is to be measured. Lower the packer into the hole. The function of the packer is to divide the hole into two independent upper and lower areas, prevent water from freely flowing in the hole during the water injection and pressurization process, and ensure that the pressurized water is concentrated in a certain area to generate stress. Start slowly injecting liquid from one end of the hole (usually the hole mouth), usually using clean water or liquid containing a tracer. At the same time, gradually increase the pressure of the injected liquid. As the pressure increases, the liquid exerts pressure on the rock mass around the hole. During the pressurization process, continuously monitor the pressure of the injected liquid. The pressure sensor is installed at the position of the hole to obtain pressure data in real time. When the pressure of the injected liquid reaches a certain level, microcracks will be generated in the rock mass. At this time, the pressure will show changes such as fluctuations or sudden drops. Record the pressure data from the start of pressurization to the rock mass rupture and subsequent processes. These data will be used for subsequent in-situ stress calculation.

[0028] Furthermore, injecting liquid into the rock mass area and pressurizing it, the specific implementation process is as follows: According to the initial tensile strength evaluation value of the rock mass area, match to obtain the initial pumping pressure and the initial pumping rate. Based on the hydraulic fracturing method, in the first measurement period, inject liquid into the rock mass and pressurize it through the initial pumping pressure and the initial pumping rate.

[0029] The initial pumping pressure refers to the pressure applied when starting to inject liquid into the rock mass during the in-situ stress measurement by the hydraulic fracturing method. It is used to overcome the initial stress state of the rock mass, enable the liquid to smoothly enter the pores or fractures of the rock mass, and create conditions for subsequent pressure increase and crack propagation. The initial pumping rate refers to the liquid injection speed when starting to inject liquid into the rock mass during the in-situ stress measurement by the hydraulic fracturing method. It is used to control the initial flow rate of the liquid entering the rock mass, ensure the stable application of pressure, and avoid the rock mass rupturing due to a sudden increase in pressure caused by too fast an injection rate, or the measurement process being long and the liquid possibly leaking due to too slow an injection rate.

[0030] Matching to obtain the initial pumping pressure and the initial pumping rate is specifically to match the initial tensile strength evaluation value of the rock mass area with the initial pumping pressures corresponding to the predefined intervals of each initial tensile strength evaluation value to determine the specific interval of the initial tensile strength evaluation value of the rock mass area, and obtain the initial pumping pressure corresponding to this interval; match the initial tensile strength evaluation value of the rock mass area with the initial pumping rates corresponding to the predefined intervals of each initial tensile strength evaluation value to determine the specific interval of the initial tensile strength evaluation value of the rock mass area, and obtain the initial pumping rate corresponding to this interval.

[0031] In this embodiment, the pumping parameters are reasonably matched according to the initial tensile strength of the rock mass, so that the initial pressure and rate can be accurately controlled, avoiding poor measurement results caused by excessive or too small initial pressure and rate, thereby improving the measurement efficiency and accuracy. Ensure that the measurement process is within the bearable range of the rock mass, make the measurement data more truly reflect the in-situ stress condition, reduce the deviation caused by unreasonable initial pumping parameters, and improve the evaluation accuracy. At the same time, fully consider the initial tensile strength of the rock mass, realize the refined control of the initial pumping pressure and rate, meet the measurement requirements under different rock mass conditions, and improve the adaptability and flexibility.

[0032] According to the evaluated value of the initial tensile strength of the rock mass area and the evaluated value of the real-time tensile strength of the rock mass area, determine whether to correct the pressure measurement process, and monitor the change of the bearing pressure of the rock mass area in real time through the pressure sensing device.

[0033] Specifically, the process of determining whether to correct the pressure measurement process is as follows: Perform a difference process on the evaluated value of the initial tensile strength of the rock mass area and the evaluated value of the real-time tensile strength of the rock mass area to obtain the tensile strength deviation of the rock mass area, check it against each predefined tensile strength deviation interval to obtain the tensile strength check result, and determine whether to correct the pressure measurement process based on the tensile strength check result.

[0034] Each tensile strength deviation interval includes a first tensile deviation interval, a second tensile deviation interval, and a third tensile deviation interval.

[0035] The tensile strength check result includes a first tensile strength check result, a second tensile strength check result, and a third tensile strength check result.

[0036] If the tensile strength check result is the second tensile strength check result, it is determined not to perform the correction of the pressure measurement process, otherwise the correction of the pressure measurement process is performed.

[0037] If the tensile strength deviation of the rock mass area belongs to the second tensile deviation interval, the tensile strength check result is determined to be the second tensile strength check result. During the second measurement period, maintain the initial pumping pressure and the initial pumping rate, inject liquid into the rock mass and apply pressure, and monitor the change of the bearing pressure of the rock mass area in real time through the pressure sensing device.

[0038] Furthermore, the execution process of correcting the pressure measurement process is as follows: If the tensile strength deviation of the rock mass area belongs to the first tensile deviation interval, the tensile strength verification result is determined as the first tensile strength verification result. According to the tensile strength deviation of the rock mass area, a proportion processing is carried out with the first tensile deviation interval to obtain the first tensile strength deviation proportion of the rock mass area. The pump injection adjustment pressure is matched and added to the initial pump injection pressure to obtain the pump injection adaptation pressure. At the same time, the real-time permeability of the rock mass area is extracted, and a ratio processing is carried out with the predefined reference permeability to obtain the permeability deviation degree value of the rock mass area. The pump injection rate adjustment coefficient is matched and multiplied by the initial pump injection rate to obtain the pump injection adaptation rate. In the second measurement period, liquid is injected into the rock mass and pressurized with the pump injection adaptation pressure and the pump injection adaptation rate, and the change in the bearing pressure of the rock mass area is monitored in real time through a pressure sensing device.

[0039] The above-mentioned proportion processing is specifically to carry out a ratio processing on the tensile strength deviation of the rock mass area and the span value of the first tensile deviation interval to obtain the first tensile strength deviation proportion of the rock mass area, where the span value of the first tensile deviation interval is the difference between the maximum value and the minimum value of the first tensile deviation interval.

[0040] The above-mentioned matching to obtain the pump injection adjustment pressure is specifically to match the first tensile strength deviation proportion of the rock mass area with the pump injection adjustment pressures corresponding to the predefined first tensile strength deviation proportion intervals, determine the specific interval of the first tensile strength deviation proportion of the rock mass area, and obtain the pump injection adjustment pressure corresponding to this interval.

[0041] The above-mentioned matching to obtain the pump injection rate adjustment coefficient is specifically to match the permeability deviation degree value of the rock mass area with the pump injection rate adjustment coefficients corresponding to the predefined permeability deviation degree value intervals, determine the specific interval of the permeability deviation degree value of the rock mass area, and obtain the pump injection rate adjustment coefficient corresponding to this interval.

[0042] If the tensile strength deviation of the rock mass area belongs to the third tensile deviation interval, the tensile strength verification result is determined as the third tensile strength verification result. According to the tensile strength deviation of the rock mass area, a proportion processing is carried out with the third tensile deviation interval to obtain the second tensile strength deviation proportion of the rock mass area. The pump injection adjustment pressure is matched and subtracted from the initial pump injection pressure to obtain the pump injection adaptation pressure. At the same time, the real-time permeability of the rock mass area is extracted, and a ratio processing is carried out with the predefined reference permeability to obtain the permeability deviation degree value of the rock mass area. The pump injection rate adjustment coefficient is matched and multiplied by the initial pump injection rate to obtain the pump injection adaptation rate. In the second measurement period, liquid is injected into the rock mass and pressurized with the pump injection adaptation pressure and the pump injection adaptation rate, and the change in the bearing pressure of the rock mass area is monitored in real time through a pressure sensing device.

[0043] The second measurement period is specifically a time interval adjacent to the first measurement period. The first measurement period is used to monitor the initial stage of the measurement process, and the second measurement period is used to correct and adjust the initial measurement process.

[0044] In this embodiment, by adjusting the pumping pressure according to the tensile strength deviation, the measurement process can be controlled more precisely, unnecessary measurement time can be reduced, and the measurement efficiency can be improved. Adjusting the pumping parameters according to the real-time state of the rock mass makes the measurement process more stable, reduces the pressure fluctuation caused by unreasonable pumping parameters, thereby improving the stability and reliability of the data, ensuring that the measurement process more conforms to the actual characteristics of the rock mass, and thus improving the accuracy of the measurement data.

[0045] In this embodiment, by monitoring the permeability of the rock mass in real time, the pumping rate can be dynamically adjusted. If the permeability decreases, the resistance of the fluid flowing in the rock mass is greater, and a higher pressure is required to make the fluid pass through the rock mass. Therefore, the pumping rate is also correspondingly reduced to avoid excessive pressure. If the permeability increases, the resistance of the fluid flowing in the rock mass is smaller, and it can easily pass through the rock mass at a lower pressure. Therefore, the pumping rate can be appropriately increased to improve the measurement efficiency. Adjusting the pumping rate according to the permeability can avoid the rock mass from being fractured or damaged due to too high pumping rate. This helps to protect the integrity of the rock mass and maintain the stability of the rock mass. Ensure that the measurement process is within the acceptable range of the rock mass, so that the measurement data can more truly reflect the in-situ stress state of the rock mass. This helps to improve the accuracy of the rock mass stability assessment.

[0046] The process of correcting the pressure measurement determination is as Figure 4 shown, Figure 4 is the flowchart of the pressure measurement determination correction. By comparing the initial and real-time tensile strengths, if the deviation between the initial and real-time tensile strengths is in the second interval, the initial pumping pressure and rate are maintained; otherwise, adjustments are required. The specific adjustment method is as follows: if the deviation is in the first interval, increase the pressure and adjust the rate in combination with the permeability; if the deviation is in the third interval, reduce the pressure and adjust the rate in the same way to optimize the measurement process and improve the data accuracy.

[0047] In the second measurement period, extract the monitored data of the pressure borne by the rock mass area. At the time point when the pressure borne by the rock mass area drops suddenly, start the receive gain compensation operation to correct the monitoring state of the pressure sensing device, and extract the monitored data of the pressure sensing device.

[0048] Specifically, to correct the monitoring state of the pressure sensing device, the specific correction process is as follows: During the second measurement period, the monitoring data of the rock area pressure of the pressure sensing device is extracted, wherein the monitoring data can be obtained in the monitoring report of the pressure sensing device. At the time point when the pressure in the rock area suddenly drops, the receiving gain compensation operation is started. The specific operation process is: extract the real-time receiving gain value of the pressure sensing device, add it to the preset gain compensation value, and obtain the receiving gain correction value of the pressure sensing device; collect the operation data of the pressure sensing device in real time, evaluate the operation quality index of the pressure sensing device, and compare it with the predefined operation quality adaptation index; if the operation quality index of the pressure sensing device is greater than or equal to the operation quality adaptation index, then maintain the monitoring of the pressure change in the rock area; if the operation quality index of the pressure sensing device is less than the operation quality adaptation index, perform difference processing on the operation quality index of the pressure sensing device and the operation quality adaptation index to obtain the operation quality deviation of the pressure sensing device, match the gain compensation coefficient, multiply it with the receiving gain correction value of the pressure sensing device, and obtain the receiving gain adaptation value of the pressure sensing device; configure the receiving gain of the pressure sensing device to complete the effective signal correction of the pressure sensing device.

[0049] The above-mentioned predefined operation quality adaptation index specifically matches the initial tensile strength assessment value of the rock mass area with the operation quality adaptation index corresponding to each predefined initial tensile strength assessment value interval, determines the specific interval of the initial tensile strength assessment value of the rock mass area, and obtains the operation quality adaptation index corresponding to the interval.

[0050] It needs to be explained that the initial tensile strength assessment value of the rock mass reflects the ability of the rock mass to resist tensile damage. If the assessment value is high, it means that the rock mass structure is dense and strong, and a higher pumping pressure and a more stable pumping rate need to be applied during hydraulic fracturing. That is, high-pressure conditions may cause the pressure sensing equipment to bear a greater mechanical load, which may cause the equipment signal strength to attenuate, the response time to be delayed, or the linearity deviation. At this time, the operating quality indicators need to monitor in real time whether the equipment performance has declined due to excessive load, and determine whether the equipment needs gain compensation. Rocks with low initial tensile strength are prone to rupture during the pressurization process, which may cause the time point of the pressure drop to be advanced and the pressure fluctuation to be larger. In this case, the pressure sensing equipment needs to have higher resolution (to detect small pressure changes) and response speed (to capture the moment of sudden drop).

[0051] In hydraulic fracturing, the point in time when the pressure suddenly drops. The pressure suddenly drops usually refers to the moment when the rock mass breaks or cracks suddenly expand due to the inability to withstand the continuously increasing pressure during the process of pumping liquid into the rock mass and pressurizing it, and the pumping pressure suddenly decreases, such as Figure 3Point a. At this time, the pressure borne by the rock mass will suddenly drop. At this time, the reception gain compensation operation is started because the sudden drop in pressure may cause a significant weakening of the received signal by the monitoring device, affecting the data quality and measurement accuracy. The reception gain compensation operation can amplify the received signal, ensure the signal strength and quality, and ensure reliable data collection.

[0052] Furthermore, correcting the monitoring state of the pressure sensing device also includes: While starting the reception gain compensation operation, synchronously extract the real-time signal amplitude of the pressure sensing device. The real-time signal amplitude can be obtained by extracting from the execution report of the pressure sensing device.

[0053] Compare the real-time signal amplitude of the pressure sensing device with the predefined signal boundary amplitude. If the real-time signal amplitude of the pressure sensing device is less than or equal to the signal boundary amplitude, then maintain the monitoring state of the pressure sensing device. If the real-time signal amplitude of the pressure sensing device is greater than the signal boundary amplitude, then match the signal amplitude correction coefficient according to the reception gain adaptation value of the pressure sensing device, perform a difference process on the real-time signal amplitude of the pressure sensing device and the signal boundary amplitude to obtain the signal amplitude deviation of the pressure sensing device, match the signal amplitude adjustment amount, multiply it by the signal amplitude correction coefficient to obtain the signal amplitude attenuation amount, and lower the real-time signal amplitude of the pressure sensing device by the signal amplitude attenuation amount to complete the correction of the monitoring state of the pressure sensing device.

[0054] The above-mentioned matching of the signal amplitude correction coefficient, the specific matching process is: match the reception gain adaptation value of the pressure sensing device with the signal amplitude correction coefficients corresponding to the predefined reception gain adaptation value intervals, determine the specific interval of the reception gain adaptation value of the pressure sensing device, and obtain the signal amplitude correction coefficient corresponding to this interval.

[0055] The above-mentioned matching of the signal amplitude adjustment amount, the specific matching process is: match the signal amplitude deviation of the pressure sensing device with the signal amplitude adjustment amounts corresponding to the predefined signal amplitude deviation intervals, determine the specific interval of the signal amplitude deviation of the pressure sensing device, and obtain the signal amplitude adjustment amount corresponding to this interval.

[0056] In this embodiment, after the reception gain compensation operation is started, the signal strength will change. Synchronously adjusting the real-time signal amplitude can ensure that the signal strength is maintained within a suitable range, avoiding signal overload or weakness. Adjusting the signal amplitude can optimize the signal quality, making subsequent data processing and analysis more accurate. By ensuring that the amplitude of the signal is within a suitable range, the interference of noise can be reduced and the signal-to-noise ratio can be improved. In addition, too high a signal amplitude may damage the receiving device, and synchronously adjusting the signal amplitude can protect the device from damage and extend the service life of the device.

[0057] The process of determining and correcting the monitoring status of a pressure sensing device is as follows Figure 5 shown Figure 5 as the flow chart for determining and correcting the monitoring status. In the second measurement period, if the pressure borne by the rock mass drops suddenly, the reception gain compensation operation needs to be started. By adjusting the reception gain value and combining the evaluation of the operation quality index, the monitoring status of the pressure sensing device is corrected to ensure the accuracy and reliability of the data. When starting the reception gain compensation, the real-time signal amplitude of the pressure sensing device should be adjusted synchronously to ensure that the signal strength is appropriate, avoiding overloading or being too weak, thereby protecting the device and improving the measurement accuracy.

[0058] Specifically, the operation quality index of the pressure sensing device is evaluated, and the specific analysis process is as follows: The operation data of the pressure sensing device includes the real-time signal strength of the pressure sensing device, the real-time linearity of the pressure sensing device, the real-time resolution of the pressure sensing device, and the real-time response duration of the pressure sensing device. Among them, the operation data can be extracted from the operation log of the pressure sensing device.

[0059] The reference signal strength, defined linearity, defined resolution, and defined response duration are extracted from the rock mass status management library.

[0060] The deviation degree between the real-time signal strength of the pressure sensing device and the reference signal strength, the deviation degree between the real-time linearity of the pressure sensing device and the defined linearity, the deviation degree between the real-time resolution of the pressure sensing device and the defined resolution, and the deviation degree between the real-time response duration of the pressure sensing device and the defined response duration are weighted and aggregated in sequence to obtain the operation quality index of the pressure sensing device. The specific analysis method is as follows: , where QA is the operation quality index of the pressure sensing device, is the signal strength of the pressure sensing device at time t, t is the time variable, , is the start time point of the second measurement period, is the end time point of the second measurement period, is the reference signal strength, is the linearity of the pressure sensing device at time t, is the defined linearity, is the resolution of the pressure sensing device at time t, is the defined resolution, is the response duration of the pressure sensing device at time t, is the defined response duration, is the weight element corresponding to the signal strength predefined in the rock mass status management library, It is the weight element corresponding to the predefined linearity in the rock mass state management library. It is the weight element corresponding to the predefined resolution in the rock mass state management library. It is the weight element corresponding to the predefined response duration in the rock mass state management library.

[0061] It should be noted that the above linearity refers to the degree of linear relationship between the output signal of the pressure sensing device and the input pressure; the resolution refers to the minimum pressure change that the pressure sensing device can detect.

[0062] Among them, the weight element corresponding to the signal strength, the weight element corresponding to the linearity, the weight element corresponding to the resolution, and the weight element corresponding to the response duration are all obtained by extracting from the rock mass state management library. The mapping relationship therein can be one-to-one or many-to-one. For example, the signal strength, linearity, resolution, and response duration respectively form a mapping set with the weight element corresponding to the signal strength, the weight element corresponding to the linearity, the weight element corresponding to the resolution, and the weight element corresponding to the response duration preset in the rock mass state management library. Substituting the real-time signal strength, linearity, resolution, and response duration into the mapping set to obtain the weight element corresponding to the signal strength, the weight element corresponding to the linearity, the weight element corresponding to the resolution, and the weight element corresponding to the response duration.

[0063] In this embodiment, through the multivariate analysis of the signal strength, linearity, resolution, and response duration, specifically considering the correlation between these parameters, a stronger signal strength can improve the signal-to-noise ratio, making the measurement of linearity more accurate and improving the operation quality of the pressure sensing device. Insufficient signal strength may lead to deviation in the evaluation of linearity because noise may mask the real signal change. Similarly, a higher signal strength can improve the resolution because a stronger signal can more clearly distinguish small pressure changes. Insufficient signal strength may limit the resolution because small pressure changes may be drowned out by noise. And too high signal strength may cause the receiving device or sensor to be overloaded. Overload will cause the sensor output signal to be distorted, unable to accurately reflect the actual pressure change, and may also cause the signal to be distorted during transmission, affecting the measurement accuracy and reducing the operation quality of the pressure sensing device; in addition, good linearity can improve the stability of the response duration because the linear relationship makes the response time of the device consistent within different pressure ranges. If the linearity is poor, the response time may fluctuate with the pressure change, which is likely to have a negative impact on the operation quality of the pressure sensing device.

[0064] According to the monitoring data of the pressure sensing device, construct a change relationship graph between pressure and time, finally obtain the in-situ stress value of the rock mass, and upload it to the preset display port for rock mass stability assessment.

[0065] Furthermore, the in-situ stress value of the rock mass is finally obtained, and the specific analysis process is as follows: According to the monitoring data of the pressure sensing device, a variation relationship diagram between pressure and time is constructed, and the fracture pressure of the rock mass area and the closure pressure of the rock mass area are extracted from the variation relationship diagram between pressure and time.

[0066] The above-mentioned construction of the variation relationship diagram between pressure and time is as Figure 3 shown Figure 3 a pressure-time curve, where the abscissa is time with the unit of minute, and the ordinate is pressure with the unit of megapascal. The pressure value corresponding to the point a where the pressure drops sharply in the figure is the fracture pressure of the rock mass area, and the pressure value corresponding to the point b where the pressure tends to be stable is the closure pressure of the rock mass area.

[0067] It should be explained that the fracture pressure is the pressure required to generate initial cracks in the rock mass. When there are obvious turning points or sudden drops in the curve, it can be judged that the rock mass has fractured, and the corresponding pressure at this time is the fracture pressure. The closure pressure is the pressure when the cracks close after stopping pressurization. When stopping water injection pressurization, as the pressure in the hole decreases, the cracks gradually close. By monitoring the pressure change, when the pressure drops to a certain extent and the pressure of the completely closed cracks tends to be flat, the corresponding pressure at this time is the closure pressure.

[0068] According to the stress-strain relationship formula, the fracture pressure of the rock mass area and the closure pressure of the rock mass area are substituted into the formula based on elastic mechanics and fracture mechanics to derive the in-situ stress value of the rock mass.

[0069] It should be explained that in this embodiment, based on the hydraulic fracturing method, it is assumed that the rock mass is a linear elastic and isotropic medium, and the fracture plane is perpendicular to the direction of the minimum horizontal principal stress. By injecting high-pressure fluid to generate hydraulic fractures in the rock mass and using the key pressure points (fracture pressure, closure pressure) in the pressure-time curve to invert the in-situ stress, the core formula is based on the theories of elastic mechanics and fracture mechanics.

[0070] In this embodiment, it is assumed that the rock mass is an elastic body, and the in-situ stress is mainly composed of vertical stress and horizontal stress. During the hydraulic fracturing process, there is a corresponding relationship between the fracture pressure and the closure pressure and the in-situ stress. The elastic mechanics formula for the rock mass in the elastic deformation stage is: , where is the minimum circumferential stress of the rock mass hole wall, is the minimum horizontal principal stress of the rock mass, is the maximum horizontal principal stress of the rock mass, and P is the pumping pressure.

[0071] 1) Fracture pressure condition (crack generation): When When = 0, fracture occurs, that is: ; where is the fracture pressure of the rock mass area.

[0072] 2) Closing pressure condition (fracture closure): The closing pressure is equal to the minimum horizontal principal stress: ; where is the closing pressure of the rock mass area.

[0073] 3) Calculation of vertical principal stress (self-weight of overlying strata): ; where is the vertical principal stress, is the rock density, is the acceleration of gravity, and h is the borehole depth.

[0074] The in-situ stress value of the rock mass is derived as follows: Calculate the vertical stress according to the borehole depth ; Calculate the minimum horizontal principal stress ; Solve for the maximum horizontal principal stress, substitute into the fracture pressure formula: , and finally obtain .

[0075] Referring to Figure 2 shown, the second aspect of the present invention provides a rock mass stability evaluation system based on in-situ stress measurement, including: an initial tensile strength evaluation module, a real-time tensile strength advance module, a pressure measurement process correction module, an equipment monitoring status correction module, an in-situ stress analysis and upload module, and a rock mass status management library.

[0076] The rock mass status management library is used to store the reference signal strength, defined linearity, defined resolution, defined response duration, and preset values of various factors.

[0077] The initial tensile strength evaluation module is connected to the real-time tensile strength advance module, the real-time tensile strength advance module is connected to the pressure measurement process correction module, the pressure measurement process correction module is connected to the equipment monitoring status correction module, the equipment monitoring status correction module is connected to the in-situ stress analysis and upload module, and the initial tensile strength evaluation module, the real-time tensile strength advance module, the pressure measurement process correction module, and the equipment monitoring status correction module are all connected to the rock mass status management library.

[0078] The initial tensile strength evaluation module is used to collect the initial characteristic data of the rock mass area and determine the initial tensile strength evaluation value of the rock mass area.

[0079] The real-time tensile strength advance module is used to inject liquid into the rock mass area and pressurize it based on the hydraulic fracturing method during the first measurement period, and extract the real-time tensile strength evaluation value of the rock mass area during the first measurement period.

[0080] The pressure measurement process correction module is used to determine whether to correct the pressure measurement process according to the initial tensile strength evaluation value of the rock mass area and the real-time tensile strength evaluation value of the rock mass area, and monitor the change of the pressure borne by the rock mass area in real time through the pressure sensing device.

[0081] The device monitoring status correction module is used to extract the pressure monitoring data of the rock mass area during the second measurement period, start the receiving gain compensation operation at the time point when the pressure borne by the rock mass area drops suddenly, correct the monitoring status of the pressure sensing device, and extract the monitoring data of the pressure sensing device.

[0082] The in-situ stress analysis and upload module is used to construct a change relationship diagram between pressure and time according to the monitoring data of the pressure sensing device, finally obtain the in-situ stress value of the rock mass, and upload it to the preset display port for rock mass stability evaluation.

[0083] The above content is only an example and illustration of the structure of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, as long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should fall within the protection scope of the present invention.

Claims

1. A method for evaluating the stability of rock masses based on in-situ stress measurement, characterized in that, Including: Collect the initial characteristic data of the rock mass area and determine the initial tensile strength evaluation value of the rock mass area; Based on the hydraulic fracturing method, inject liquid into the rock mass area and pressurize it during the first measurement period, and at the same time extract the real-time tensile strength evaluation value of the rock mass area during the first measurement period; According to the initial tensile strength evaluation value of the rock mass area and the real-time tensile strength evaluation value of the rock mass area, determine whether to correct the pressure measurement process, and monitor the change of the pressure borne by the rock mass area in real time through a pressure sensing device; During the second measurement period, extract the pressure monitoring data of the rock mass area. At the time point when the pressure borne by the rock mass area drops suddenly, start the receiving gain compensation operation to correct the monitoring state of the pressure sensing device and extract the monitoring data of the pressure sensing device; According to the monitoring data of the pressure sensing device, construct a change relationship graph between pressure and time, finally obtain the in-situ stress value of the rock mass, and upload it to a preset display port for rock mass stability evaluation.

2. The rock mass stability evaluation method based on in-situ stress measurement according to claim 1, wherein: The specific determination process of the initial tensile strength evaluation value of the rock mass area is as follows: The initial characteristic data of the rock mass area includes the elastic modulus of the rock mass in the rock mass area, the Poisson's ratio of the rock in the rock mass area, the hardness of the rock mass in the rock mass area, and the density of the rock mass in the rock mass area; Normalize the elastic modulus of the rock mass in the rock mass area, the Poisson's ratio of the rock in the rock mass area, the hardness of the rock mass in the rock mass area, and the density of the rock mass in the rock mass area respectively to obtain the normalization processing results, and then perform weighted aggregation processing in sequence to obtain the initial tensile strength evaluation value of the rock mass area.

3. The method for evaluating the stability of rock mass based on in-situ stress measurement according to claim 1, wherein: The specific implementation process of injecting liquid into the rock mass area and pressurizing it is as follows: According to the initial tensile strength evaluation value of the rock mass area, match the initial injection pressure and the initial injection rate. Based on the hydraulic fracturing method, during the first measurement period, inject liquid into the rock mass and pressurize it through the initial injection pressure and the initial injection rate; The specific method of matching the initial injection pressure and the initial injection rate is to match the initial tensile strength evaluation value of the rock mass area with the initial injection pressure corresponding to each predefined initial tensile strength evaluation value interval to determine the specific interval of the initial tensile strength evaluation value of the rock mass area, and obtain the initial injection pressure corresponding to this interval; match the initial tensile strength evaluation value of the rock mass area with the initial injection rate corresponding to each predefined initial tensile strength evaluation value interval to determine the specific interval of the initial tensile strength evaluation value of the rock mass area, and obtain the initial injection rate corresponding to this interval.

4. The rock mass stability evaluation method based on in-situ stress measurement according to claim 1, wherein: The specific determination process of determining whether to correct the pressure measurement process is as follows: Perform a difference process on the initial tensile strength evaluation value of the rock mass area and the real-time tensile strength evaluation value of the rock mass area to obtain the tensile strength deviation of the rock mass area, and check it with each predefined tensile strength deviation interval to obtain the tensile strength check result. Based on the tensile strength check result, determine whether to correct the pressure measurement process; Each of the tensile strength deviation intervals includes a first tensile deviation interval, a second tensile deviation interval, and a third tensile deviation interval; The tensile strength verification results include the first tensile strength verification result, the second tensile strength verification result, and the third tensile strength verification result; If the tensile strength verification result is the second tensile strength verification result, it is determined not to perform the correction of the pressure measurement process, otherwise the correction of the pressure measurement process is performed; If the tensile strength deviation of the rock mass area belongs to the second tensile deviation interval, the tensile strength verification result is determined to be the second tensile strength verification result. During the second measurement period, the initial pumping pressure and the initial pumping rate are maintained, liquid is injected into the rock mass and pressurized, and the change in the pressure borne by the rock mass area is monitored in real time through a pressure sensing device.

5. The rock mass stability evaluation method based on in-situ stress measurement according to claim 4, wherein: The implementation of the correction of the pressure measurement process is specifically as follows: If the tensile strength deviation of the rock mass area belongs to the first tensile deviation interval, the tensile strength verification result is determined to be the first tensile strength verification result. According to the tensile strength deviation of the rock mass area, a ratio is processed with the first tensile deviation interval to obtain the first deviation ratio of the tensile strength of the rock mass area, and the adjusted pumping pressure is matched. Added to the initial pumping pressure to obtain the adjusted pumping pressure. At the same time, the real-time permeability of the rock mass area is extracted, and a ratio is processed with the predefined reference permeability to obtain the permeability deviation degree value of the rock mass area. The adjusted pumping rate coefficient is matched and multiplied by the initial pumping rate to obtain the adjusted pumping rate. During the second measurement period, liquid is injected into the rock mass and pressurized with the adjusted pumping pressure and the adjusted pumping rate, and the change in the pressure borne by the rock mass area is monitored in real time through a pressure sensing device; If the tensile strength deviation of the rock mass area belongs to the third tensile deviation interval, the tensile strength verification result is determined to be the third tensile strength verification result. According to the tensile strength deviation of the rock mass area, a ratio is processed with the third tensile deviation interval to obtain the second deviation ratio of the tensile strength of the rock mass area, and the adjusted pumping pressure is matched. Subtracted from the initial pumping pressure to obtain the adjusted pumping pressure. At the same time, the real-time permeability of the rock mass area is extracted, and a ratio is processed with the predefined reference permeability to obtain the permeability deviation degree value of the rock mass area. The adjusted pumping rate coefficient is matched and multiplied by the initial pumping rate to obtain the adjusted pumping rate. During the second measurement period, liquid is injected into the rock mass and pressurized with the adjusted pumping pressure and the adjusted pumping rate, and the change in the pressure borne by the rock mass area is monitored in real time through a pressure sensing device.

6. The rock mass stability evaluation method based on in-situ stress measurement according to claim 1, characterized in that: The correction of the monitoring state of the pressure sensing device is specifically as follows: During the second measurement period, pressure monitoring data of the rock mass area of the pressure sensing device is extracted. When the pressure in the rock mass area drops suddenly, the reception gain compensation operation is started. The specific operation process is as follows: Extract the real-time reception gain value of the pressure sensing device, add it to the preset gain compensation value to obtain the reception gain correction value of the pressure sensing device. Real-time collect the operation data of the pressure sensing device, evaluate the operation quality index of the pressure sensing device, and compare it with the predefined operation quality adaptation index. If the operation quality index of the pressure sensing device is greater than or equal to the operation quality adaptation index, the pressure change monitoring of the rock mass area is maintained. If the operation quality index of the pressure sensing device is less than the operation quality adaptation index, the difference between the operation quality index of the pressure sensing device and the operation quality adaptation index is processed to obtain the operation quality deviation of the pressure sensing device. The gain compensation coefficient is matched and multiplied by the reception gain correction value of the pressure sensing device to obtain the reception gain adaptation value of the pressure sensing device, and the reception gain of the pressure sensing device is configured to complete the correction of the effective signal of the pressure sensing device.

7. The rock mass stability evaluation method based on in-situ stress measurement according to claim 6, characterized in that: The correction of the monitoring state of the pressure sensing device further includes: While starting the reception gain compensation operation, synchronously extract the real-time signal amplitude of the pressure sensing device; Compare the real-time signal amplitude of the pressure sensing device with the predefined signal boundary amplitude. If the real-time signal amplitude of the pressure sensing device is less than or equal to the signal boundary amplitude, the monitoring state of the pressure sensing device is maintained. If the real-time signal amplitude of the pressure sensing device is greater than the signal boundary amplitude, according to the reception gain adaptation value of the pressure sensing device, the signal amplitude correction coefficient is matched. The difference between the real-time signal amplitude of the pressure sensing device and the signal boundary amplitude is processed to obtain the signal amplitude deviation of the pressure sensing device. The signal amplitude adjustment amount is matched and multiplied by the signal amplitude correction coefficient to obtain the signal amplitude attenuation amount, and the real-time signal amplitude of the pressure sensing device is decreased by the signal amplitude attenuation amount to complete the correction of the monitoring state of the pressure sensing device.

8. The method for evaluating the stability of a rock mass based on in-situ stress measurement according to claim 6, wherein: The specific analysis process for evaluating the operation quality index of the pressure sensing device is as follows: The operation data of the pressure sensing device includes the real-time signal strength of the pressure sensing device, the real-time linearity of the pressure sensing device, the real-time resolution of the pressure sensing device, and the real-time response duration of the pressure sensing device; Extract the reference signal strength, defined linearity, defined resolution, and defined response duration from the rock mass state management library; The deviation degree between the real-time signal strength of the pressure sensing device and the reference signal strength, the deviation degree between the real-time linearity of the pressure sensing device and the defined linearity, the deviation degree between the real-time resolution of the pressure sensing device and the defined resolution, and the deviation degree between the real-time response duration of the pressure sensing device and the defined response duration are weighted and aggregated in sequence to obtain the operation quality index of the pressure sensing device.

9. The rock mass stability evaluation method based on in-situ stress measurement according to claim 1, characterized in that: The specific analysis process for finally obtaining the in-situ stress value of the rock mass is as follows: Construct a variation relationship diagram between pressure and time based on the monitoring data of the pressure sensing device, and extract the fracture pressure of the rock mass area and the closure pressure of the rock mass area from the variation relationship diagram between pressure and time; According to the stress-strain relationship formula, substitute the fracture pressure of the rock mass area and the closure pressure of the rock mass area into the formula based on elastic mechanics and fracture mechanics to derive the in-situ stress value of the rock mass.

10. A system applying a rock mass stability assessment method based on in-situ stress measurement according to any one of claims 1-9, characterized in that: Including: An initial tensile strength evaluation module, configured to collect initial characteristic data of the rock mass area and determine the initial tensile strength evaluation value of the rock mass area; A real-time tensile strength prediction module, configured to inject liquid and pressurize the rock mass area based on the hydraulic fracturing method during a first measurement period, and extract the real-time tensile strength evaluation value of the rock mass area during the first measurement period; A pressure measurement process correction module, configured to determine whether to correct the pressure measurement process according to the initial tensile strength evaluation value of the rock mass area and the real-time tensile strength evaluation value of the rock mass area, and monitor the change of the pressure borne by the rock mass area in real time through the pressure sensing device; A device monitoring status correction module, configured to extract the pressure monitoring data of the rock mass area during a second measurement period, start the reception gain compensation operation at the time point when the pressure borne by the rock mass area drops suddenly, correct the monitoring status of the pressure sensing device, and extract the monitoring data of the pressure sensing device; An in-situ stress analysis and upload module, configured to construct a variation relationship diagram between pressure and time according to the monitoring data of the pressure sensing device, finally obtain the in-situ stress value of the rock mass, and upload it to a preset display port for rock mass stability evaluation.

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