Hydraulic fracturing pressure relief effect and formation parameter integrated detection device and evaluation method

Abstract

The invention relates to the technical field of hydraulic fracturing integrated detection, and discloses a hydraulic fracturing pressure relief effect and formation parameter integrated detection device and evaluation method, and the device comprises a high-pressure fracturing and packing system, a multi-source information monitoring system and an intelligent control and data analysis system. The high-pressure fracturing and packing system is provided with a center anchor rod with a sliding way, an intelligent packer capable of moving along the center anchor rod and a high-pressure pumping unit, and precise packing and fracturing are achieved. The multi-source information monitoring system monitors crack extension and stress change in real time through distributed optical fibers, micro-seismic arrays and the like. According to the method, synchronous integration of pressure relief construction, formation parameter detection and effect evaluation is achieved, the problems that in the prior art, pressure relief and detection are disjointed, effect evaluation is lagged, and parameter design is blind are solved, and the accuracy and safety of deep engineering rock stratum control are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydraulic fracturing integrated detection, and particularly relates to a hydraulic fracturing pressure relief effect and formation parameter integrated detection device and evaluation method. BACKGROUND

[0002] With the acceleration of economic construction, mineral resources exploitation and traffic tunnel engineering continue to expand to deep strata. In the deep high-stress environment, dynamic disasters such as rock burst and rock burst frequently occur, which not only seriously threatens the safety of construction personnel and restricts the efficiency of the project, but also causes huge economic losses. Therefore, implementing active pressure relief on high-stress rock mass to release accumulated elastic energy has become a core technical measure to ensure the safety of underground engineering.

[0003] Hydraulic fracturing method is widely used in coal mines, metal mines and tunnel engineering due to its significant pressure relief effect, wide application range and convenient construction. The technical principle is that high-pressure water is injected into the target section of the rock mass through the borehole, the fracture network is artificially created and expanded, the high stress concentration state of the original rock is destroyed, and the stress is transferred to the deep part, thereby achieving pressure relief and energy release. However, long-term engineering practice shows that the existing technology has the core defect of serious disconnection between pressure relief and detection, and is in a state of relying on experience and semi-blind application.

[0004] The specific problems are as follows: first, the data value utilization rate is low. Traditional operation only aims to create fractures. The parameters such as pressure and flow recorded during construction are only used to judge the success or failure of rock breaking. The pressure-time curve containing geomechanical information is not analyzed in depth. Key data is idle or cannot be used due to insufficient collection accuracy. Second, the effect evaluation is lagging and indirect. It relies on post-validation methods such as borehole television observation of fractures and microseismic monitoring of energy activity, which cannot provide real-time feedback on construction effect. The mode of construction first and evaluation later easily leads to time delay and cost increase. Third, the design parameters are highly dependent on experience. Due to the lack of accurate data of the principal stress in the target area, the layout of pressure relief holes and the design of fracturing parameters are mostly based on experience, which may reduce the pressure relief efficiency due to the mismatch between hole position and principal stress direction, or cause safety hazards due to improper parameters. Fourth, the fracture expansion is difficult to control and measure. Fractures tend to extend randomly along weak planes, and operators cannot real-time perceive the extension range and path, which may lead to insufficient pressure relief and hidden dangers or secondary disasters such as water inrush caused by excessive expansion.

[0005] In summary, the existing technology has the bottlenecks of process uncertainty, difficulty in effect evaluation, experience-based parameters, and extensive control. It is urgent to develop new technical equipment that integrates active pressure relief, parameter detection, and real-time effect evaluation, and promote hydraulic fracturing from a simple pressure relief process to a measurable, evaluable, and controllable precise rock stratum control method. The present application is proposed based on this urgent need. SUMMARY

[0006] The purpose of this invention is to provide an integrated detection device and evaluation method for hydraulic fracturing decompression effect and formation parameters. It aims to overcome the shortcomings of existing hydraulic fracturing technologies, such as the disconnect between decompression and detection, unknown process, lagging evaluation, and crude control. The invention provides a technical solution that can simultaneously achieve rock layer decompression and accurate measurement of key formation parameters in integrated operations, dynamically select fracturing segments based on real-time detection to avoid ineffective fracturing, monitor and guide fracture propagation morphology in real time, and conduct real-time, quantitative evaluation and feedback optimization of decompression effect during construction. This will promote the upgrading of hydraulic fracturing technology to a measurable, evaluable, and controllable precise rock layer control method.

[0007] To achieve the above objectives, the following technical solution is adopted: In a first aspect, the present invention provides an integrated detection device for hydraulic fracturing and depressurization effect and formation parameters, including a high-pressure fracturing and sealing system, a multi-source information monitoring system, a leakage channel dynamic management system, and an intelligent control and data analysis system. The high-pressure fracturing and sealing system is used for adaptive sealing and high-pressure hydraulic fracturing of the target fracturing section within the borehole. The multi-source information monitoring system is used to collect multi-source information from inside and outside the wellbore during the fracturing process in real time. The dynamic management system for leakage channels is integrated into the high-pressure fracturing and sealing system; The intelligent control and data analysis system is electrically connected to the high-pressure fracturing and sealing system and the multi-source information monitoring system, respectively, and is used to receive and process monitoring data, control the fracturing process, and calculate formation parameters and evaluate the depressurization effect in real time.

[0008] Furthermore, the high-pressure fracturing and sealing system includes a central anchor slide rail unit, an intelligent movable double packer unit, a high-pressure pumping unit, and a guide fracture initialization unit; The central anchor slide rail unit includes a high-strength hollow central anchor, the outer wall of the central anchor is provided with a precision straight slide rail, and a sensing optical cable is pre-embedded in the anchor wall of the central anchor. The central anchor also functions as a support transmission and water injection channel. The intelligent movable dual packer unit includes two independently controlled packers. Each packer is equipped with a rubber sleeve seat, a rubber sleeve, a central tube, a sealing ring, a drive device, and an expansion device. The packer achieves precise axial sliding by engaging a slider with a slide rail. The rubber sleeve integrates a micro sensor to monitor the sealing status in real time. The high-pressure pump injection unit comprises a water storage tank, a motor, a high-pressure water pump, a flow meter, a pressure sensor and an accumulator, the water storage tank is connected with the high-pressure water pump through a water delivery pipe, an output end of the high-pressure water pump is communicated with a water injection channel of the center anchor rod, a water pressure fracturing outlet is arranged on a fracturing section of the center anchor rod, and the pressure sensor and the flow meter are respectively connected with the intelligent control and data analysis system. The guide fracture initialization unit is integrated in the fracturing section of the center anchor rod and adopts a controllable directional perforation technology.

[0009] Further, the leakage channel dynamic management system comprises a plurality of micro high-pressure sealing capsules, the micro high-pressure sealing capsules are arranged on the center anchor rod of the center anchor rod slide unit and are located outside the sealing range of the intelligent movable double packer unit, and the micro high-pressure sealing capsules are connected with the intelligent control and data analysis system.

[0010] Further, the multi-source information monitoring system comprises an in-hole monitoring unit and a hole-out monitoring unit; the in-hole monitoring unit comprises a distributed optical fiber sensing array and a downhole television / sonic probe, the distributed optical fiber sensing array is composed of distributed optical fibers arranged along the wall of the borehole or the outer wall of the packer, and the sonic probe is used for imaging the wall of the borehole before and after fracturing; the hole-out monitoring unit comprises a microseismic monitoring array and a borehole stress meter, the microseismic monitoring array is arranged around the fractured borehole and is used for capturing microseismic events caused by crack propagation, and the borehole stress meter is installed in a neighboring observation hole and is used for monitoring the stress change of the surrounding rock mass during pressure relief; the distributed optical fiber, the sonic probe, the microseismic monitoring array and the borehole stress meter are respectively connected with the intelligent control and data analysis system.

[0011] Further, the high-pressure pump injection unit further comprises a backing plate, the high-pressure water pump is fixedly installed through the backing plate, the motor provides power for the high-pressure water pump, the accumulator is communicated with an output pipeline of the high-pressure water pump and is used for stabilizing the injection pressure, and the position of the water pressure fracturing outlet corresponding to the fracturing section of the center anchor rod is adapted to the sealing range of the packer to form an independent fracturing section space.

[0012] In the second aspect, the application provides an integrated evaluation method for pressure relief effect and formation parameters based on the device, comprising the following steps: S1, drilling a borehole in a target pressure relief area, lowering the integrated detection device to a preset depth, dynamically selecting and positioning the best fracturing section according to the monitoring data, and performing sealing operation; S2, starting the intelligent movable double packer to isolate an independent fracturing section and recording an initial stable pressure P0; S3, performing a pressure cycle operation, and sequentially recording an initial fracture pressure Pc, a fracture propagation pressure Ps, an instantaneous closing pressure, and a fracture reopening pressure Pr; S4, calculating a maximum horizontal principal stress and a minimum horizontal principal stress based on the pressure data collected in steps S2 and S3; at the same time, fusing multi-source monitoring data to construct a three-dimensional fracture model of the fracturing region; S5, based on the three-dimensional fracture model and the monitoring data, performing quantitative evaluation from multiple dimensions of a pressure relief range index, a stress release rate, an energy dissipation index, and a fracture complexity to obtain a pressure relief effect index; S6, comparing the pressure relief effect index with a preset target, if the target is met, solidifying the current fracturing parameters for subsequent operations; if the target is not met, analyzing the reasons and adjusting the fracturing parameters accordingly to optimize or reinforce the fracturing.

[0013] Further, in step S4, the maximum horizontal principal stress σ H is calculated as follows: where T is the tensile strength of the rock, σ h is the minimum horizontal principal stress, equal to Ps.

[0014] Further, in step S5, the calculation formula of the stress release rate is as follows: where ω is the stress release rate, σ before is the initial stress of the rock mass before fracturing, σ after is the residual stress of the rock mass after stable fracturing; Further, the energy dissipation index is evaluated by the following method: calculating the total energy injected by the high-pressure pump injection unit during the entire fracturing process, and the total energy released by rock mass rupture through microseismic event magnitude conversion, analyzing the ratio of the two to evaluate the energy conversion efficiency; The quantification method of the fracture complexity includes: fractal dimension calculation on microseismic event point cloud data, and / or analysis of the fluctuation frequency and amplitude of strain or acoustic signals collected by the distributed optical fiber sensing array.

[0015] Further, the pressure cycle operation in step S3 specifically includes: initial pressurization stage: water injection at constant flow rate, pressure rises to rock mass fracture, peak pressure is recorded; fracture propagation and pressure maintenance stage: maintain the pressure at the fracture propagation pressure level for a set time; instantaneous closing and pressure recording stage: quickly close the high-pressure water pump, record the instantaneous closing pressure; Pressure relief and re-tensioning stage: after the pressure is reduced to zero, re-pressurize to reopen the fracture, and record the re-tensioning opening pressure.

[0016] The beneficial effects of the present application are embodied in: Firstly, by integrating high-pressure fracturing, intelligent packer and multi-source monitoring system into an integrated device, active pressure relief of rock stratum and in-situ accurate measurement of key stratum parameters are simultaneously completed in one operation cycle, significantly improving operation efficiency and immediacy of data acquisition, and fundamentally solving the problem of separation of pressure relief and detection in traditional technology.

[0017] Secondly, the best fracturing section is dynamically optimized with the help of real-time feedback of rock mass structure information, and the packer is accurately positioned through guided initialization, effectively avoiding invalid fracturing in broken rock stratum, and improving the pertinence and one-time success rate of pressure relief operation.

[0018] Furthermore, by comprehensively utilizing multi-source information such as distributed optical fiber sensing and microseismic monitoring, real-time and three-dimensional visual monitoring of fracture initiation, expansion trajectory, spatial form and influence range is realized, making the construction process from unknown to transparent and controllable, providing a basis for timely intervention and guidance.

[0019] Finally, by establishing a multi-dimensional quantitative evaluation index system and a closed-loop feedback optimization mechanism, the pressure relief effect can be judged in real time during the construction process, and the subsequent parameters can be dynamically adjusted, realizing the fundamental change from empirical and extensive construction to data-driven and precise control, thereby ensuring the safety of the project while improving the reliability and economy of the pressure relief effect. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0021] Figure 1 A structure schematic view of a water pressure fracturing pressure relief effect and stratum parameter integrated detection device provided by the embodiment of the present application; Figure 2 An internal structure diagram of an intelligent movable packer in a water pressure fracturing pressure relief effect and stratum parameter integrated detection device provided by the embodiment of the present application; Figure 3 A center anchor rod sectional view of a water pressure fracturing pressure relief effect and stratum parameter integrated detection device provided by the embodiment of the present application; Figure 4A center anchor rod plan view of a water pressure fracturing pressure relief effect and formation parameter integrated detection device provided by the embodiment of the present application; Figure 5 A working schematic view of a water pressure fracturing pressure relief effect and formation parameter integrated detection device provided by the embodiment of the present application; Figure 6 A flow chart of a detection device and evaluation method provided by the embodiment of the present application; Figure 7 A flow chart of a pressure relief effect and formation parameter integrated evaluation method provided by the embodiment of the present application.

[0022] Explanation of reference numerals: 1, packer; 2, acoustic wave probe; 3, distributed optical fiber; 4, water pressure fracturing outlet; 5, center anchor rod; 6, upper interface; 7, rubber sleeve seat; 8, rubber sleeve; 9, lower interface; 10, center tube; 11, sealing ring; 12, driving device; 13, expansion device; 14, slide; 15, anchor rod wall; 16, micro high-pressure blocking capsule; 17, pressure sensor; 18, rock stratum; 19, roadway; 20, water storage tank; 21, motor; 22, high-pressure water pump; 23, pad; 24, integrated detection device; 25, water delivery pipe. DETAILED DESCRIPTION

[0023] The embodiments of the present application will be described in detail by specific, concrete examples below, and those skilled in the art can easily understand other advantages and effects of the present application from the disclosure of the present specification. The present application can also be implemented or applied by other different specific embodiments, and each detail in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0024] The specific embodiments of the present application will be described in further detail below in combination with the drawings and embodiments.

[0025] Embodiment 1: The water pressure fracturing pressure relief effect and formation parameter integrated detection device provided by the embodiment of the application comprises a high-pressure fracturing and sealing system, a multi-source information monitoring system, a leakage channel dynamic management system and an intelligent control and data analysis system; the high-pressure fracturing and sealing system is used for adaptive sealing and high-pressure water fracturing in a target fracturing section in a borehole; the multi-source information monitoring system is used for real-time acquisition of multi-source information in the borehole and outside the borehole in the fracturing process; the leakage channel dynamic management system is integrated on the high-pressure fracturing and sealing system; the intelligent control and data analysis system is electrically connected with the high-pressure fracturing and sealing system and the multi-source information monitoring system, and is used for receiving and processing monitoring data, controlling the fracturing process, and real-time calculation of formation parameters and evaluation of pressure relief effect.

[0026] In the embodiment, the high-pressure fracturing and sealing system is a core innovative system, and is used for realizing adaptive accurate sealing by relying on real-time detection data, and comprises a central anchor rod slide, an intelligent movable double packer, a high-pressure pump injection and a guide crack initialization. The central anchor rod slide unit takes a high-strength hollow anchor rod and a precise linear slide on the outer wall as cores, has the functions of supporting transmission and water injection channel, and can pre-bury a sensing optical cable in the wall; the intelligent movable double packer unit comprises two independently controlled packers, realizes axial accurate sliding by engaging the slide and the slide way, and integrates a micro sensor in a rubber tube to realize real-time monitoring of the sealing state; the high-pressure pump injection unit is composed of a variable frequency high-pressure water pump, a flowmeter, a pressure sensor and an accumulator, injects high-pressure water into the fracturing section, accurately records the injection flow and the pressure-time curve, and completes the fixed-point-pressure relief-moving operation cycle by the central controller and the slide unit; the guide crack initialization unit is integrated in the anchor rod fracturing section, adjusts the perforation direction according to the maximum principal stress direction inverted in real time underground by means of controllable directional perforation technology, and guarantees accurate crack initiation.

[0027] In addition, the leakage channel dynamic management system is provided, and a micro high-pressure sealing capsule that can be accurately triggered is arranged on the central anchor rod slide unit. After the intelligent movable double packer is positioned and fixed, the micro high-pressure sealing capsule outside the sealing section is triggered to seal the high-pressure water hole outside the sealing section, so that water leakage is prevented.

[0028] The multi-source information monitoring system comprises an in-hole monitoring unit and a borehole monitoring unit. The in-hole monitoring unit comprises a distributed optical fiber sensing array arranged along the borehole wall or the outer wall of the packer (used for real-time monitoring of crack initiation, expansion track and range in the fracturing process, and depicting crack geometry by analyzing strain / sound wave signals) and a downhole television / acoustic probe (used for imaging the borehole wall before and after fracturing, and intuitively comparing crack morphology); the borehole monitoring unit comprises a microseismic monitoring array arranged around the fracturing borehole (used for capturing microseismic events caused by crack expansion, and three-dimensionally positioning the crack network) and a borehole stress meter installed in a neighboring observation borehole (used for monitoring the change of stress of the surrounding rock mass in the pressure relief process).

[0029] The intelligent control and data analysis system includes a central controller and data analysis and visualization software. The central controller is responsible for receiving data from all sensors and controlling the pressurization, pressure holding, and pressure relief actions of the high-pressure pumping unit. The data analysis and visualization software processes pressure-time data, fiber optic data, and microseismic data in real time and can automatically calculate formation parameters and pressure relief effect indicators.

[0030] In some embodiments, such as Figures 1 to 5 As shown, the high-pressure fracturing and sealing system includes a central anchor bolt sliding unit, an intelligent movable double packer unit, a high-pressure pumping unit, and a guide fracture initialization unit. The central anchor bolt sliding unit includes a high-strength hollow central anchor bolt 5. The outer wall of the central anchor bolt 5 is provided with a precision straight sliding track 14. A sensing optical cable is pre-embedded in the anchor bolt wall 15 of the central anchor bolt 5. The central anchor bolt 5 also functions as a support transmission and water injection channel. The intelligent movable double packer unit includes two independently controlled packers 1. Each packer 1 is equipped with a rubber sleeve seat 7, a rubber sleeve 8, a central tube 10, a sealing ring 11, a driving device 12, and an expansion device 13. The packer 1 achieves precise axial sliding through the engagement of a slider with the sliding track 14. The cylinder 8 integrates a micro sensor to monitor the sealing status in real time; the high-pressure pump injection unit includes a water storage tank 20, a motor 21, a high-pressure water pump 22, a flow meter, a pressure sensor 17, and an accumulator. The water storage tank 20 is connected to the high-pressure water pump 22 through a water supply pipe 25. The output end of the high-pressure water pump 22 is connected to the water injection channel of the central anchor 5. The fracturing section of the central anchor 5 is provided with a water pressure fracturing outlet 4. The pressure sensor 17 and the flow meter are respectively connected to the intelligent control and data analysis system. The guide fracture initialization unit is integrated into the fracturing section of the central anchor 5 and adopts controllable directional perforation technology. The two ends of the central anchor 5 are respectively provided with an upper interface 6 and a lower interface 9 for component assembly and pipeline connection.

[0031] This high-pressure fracturing and sealing system achieves precise and controllable fracturing operations through the coordinated operation of four units. The central anchor rail unit, as the core load-bearing and force-transmitting structure, provides rigid support for the entire device with its high-strength hollow central anchor 5. Its internal cavity forms the main channel for high-pressure water injection, while the precision linear rail 14 on the outer wall provides precise guidance for the movement of the packer 1. The intelligent movable double packer unit is key to dynamic sealing. Its two packers 1 can slide independently along the rail 14. After accurate positioning, the rubber sleeve 8 is expanded by the drive device 12 and the expansion device 13, tightly fitting against the borehole wall to form an independent fracturing section. The high-pressure pumping unit provides the power source for the entire process. The motor 21 drives the high-pressure water pump 22, pressurizing the water in the storage tank 20 and injecting it into the sealed rock mass section through the water pipe 25 and the channel inside the central anchor 5 from the water pressure fracturing outlet 4. The pressure sensor 17 and flow meter monitor the process parameters in real time. Before fracturing begins, the guided fracture initialization unit, based on geological information or real-time inversion of the maximum principal stress direction, uses controlled directional perforation technology to form a preset fracture initiation point on the target rock mass, actively guiding the fracture to expand in a predetermined dominant direction rather than developing randomly.

[0032] In some embodiments, such as Figure 3 As shown, the leakage channel dynamic management system includes several miniature high-pressure sealing capsules 16. The miniature high-pressure sealing capsules 16 are deployed on the central anchor 5 of the central anchor slide unit and are located outside the sealing range of the intelligent movable double packer unit. The miniature high-pressure sealing capsules 16 are connected to the intelligent control and data analysis system and can be precisely triggered to seal the high-pressure water holes outside the sealing section.

[0033] Once the intelligent movable dual packer has moved to the target section and completed its main packing expansion, the intelligent control and data analysis system issues a command to trigger the miniature high-pressure sealing capsules 16 located outside the packer section. These capsules rapidly expand, and their filling material, under pressure, is forced into and seals any tiny gaps that may exist where the packer meets the borehole wall, or blocks existing seepage channels such as primary fractures and joints on the borehole wall in that section. This process is a dynamic and active enhancement of the main packer, designed to pre-close potential leakage paths before high-pressure water injection, thereby creating a near-ideal sealed high-pressure chamber within the borehole.

[0034] This embodiment significantly improves the reliability and integrity of the containment. By actively sealing secondary leakage channels, it effectively prevents high-pressure water from leaking out from non-target areas on both sides of the main containment section during fracturing, ensuring that the injected pressure can fully act on the target rock mass. This is crucial for obtaining accurate pressure-time curves, successful fracturing, and accurate inversion of formation parameters. Simultaneously, it reduces the ineffective dissipation of water resources and lowers the risk of surrounding rock softening or secondary disasters that may be caused by high-pressure water seepage into non-target rock layers.

[0035] For example, the specific application of this dynamic management system for leak channels can be adjusted according to actual geological conditions. For instance, in coal seams with relatively fractured rock, more or larger micro high-pressure sealing capsules 16 can be installed to address more developed fracture networks. Furthermore, the triggering method can be sequential, i.e., the capsule closest to the packer is triggered first, and then the outermost capsules are triggered based on pressure monitoring, achieving precise, tiered sealing. Additionally, the filling material of the capsules can be selected based on the chemical properties of the groundwater to ensure its durability and sealing effect after expansion. It should be noted that the specific quantities, specifications, triggering logic, and material selections listed above are merely examples and can be modified according to engineering needs in actual applications, without departing from the core principle of this system to manage leak channels through active sealing.

[0036] In some embodiments, such as Figure 1 As shown, the multi-source information monitoring system includes an in-well monitoring unit and an out-of-well monitoring unit. The in-well monitoring unit includes a distributed fiber optic sensor array and a downhole television / acoustic probe 2. The distributed fiber optic sensor array consists of distributed optical fibers 3 laid along the borehole wall or the outer wall of the packer 1. The acoustic probe 2 is used to image the borehole wall before and after fracturing. The out-of-well monitoring unit includes a microseismic monitoring array and a borehole stress gauge. The microseismic monitoring array is arranged around the fracturing borehole to capture microseismic events caused by fracture propagation. The borehole stress gauge is installed in an adjacent observation hole to monitor the stress changes of the surrounding rock mass during the decompression process. The distributed optical fibers 3, the acoustic probe 2, the microseismic monitoring array, and the borehole stress gauge are respectively connected to the intelligent control and data analysis system.

[0037] This multi-source information monitoring system constructs a three-dimensional, real-time monitoring network extending from the borehole interior to the surrounding rock mass through the coordinated deployment of monitoring units inside and outside the borehole. Inside the borehole, a distributed fiber optic sensor array continuously senses subtle changes in the strain field or acoustic emission signals caused by fracture initiation and propagation via distributed optical fibers 3 laid along the borehole wall or the outer wall of the packer 1. This enables close-range, high-resolution real-time mapping of the fracture propagation trajectory, velocity, and extent. Simultaneously, an acoustic probe 2 scans and images the borehole wall before and after fracturing, providing a direct visual comparison of fracture morphology. Outside the borehole, a microseismic monitoring array deployed around the fracturing borehole can sensitively capture elastic waves (microseismic events) released during the long-range propagation of fractures. By inversion calculations, the three-dimensional spatial coordinates of these events are determined, thus outlining the spatial distribution of the entire fracture network. Borehole stress gauges installed in adjacent observation holes directly monitor the dynamic changes in rock mass stress before and after fracturing and decompression. Data collected by all monitoring units is transmitted in real-time to an intelligent control and data analysis system for fusion processing.

[0038] For example, the specific configuration of this multi-source information monitoring system can be flexibly adjusted according to engineering objectives and geological conditions. For instance, in projects aiming to precisely control fracture extension direction, the density of distributed optical fibers 3 within the well can be increased to obtain more refined strain field evolution data. Similarly, when assessing the impact of pressure relief on a specific roadway or chamber, microseismic monitoring sensors can be densely deployed around it, and borehole stress gauges can be added. Furthermore, for homogeneous hard rock formations, microseismic monitoring may be more crucial for characterizing the fracture network; while for soft rock or fractured formations, the monitoring of near-field deformation by distributed optical fibers may be more critical. It should be noted that the adjustments to the sensor types, deployment schemes, and data weighting configurations described above are merely examples; any scheme based on multi-source information fusion to achieve comprehensive monitoring of the fracturing process is within the scope of this invention.

[0039] In some embodiments, such as Figure 5 As shown, the intelligent control and data analysis system includes a central controller and data analysis and visualization software. The central controller is connected to the drive unit 12, expansion unit 13, high-pressure water pump 22, and pressure sensor 17 of the high-pressure fracturing and sealing system, the monitoring components of the multi-source information monitoring system, and the miniature high-pressure sealing capsule 16 of the leakage channel dynamic management system. It is used to receive all sensor data and control actions such as pressurization, pressure holding, pressure relief, and sealing triggering. The data analysis and visualization software is used to process pressure-time data, fiber optic sensing data, and microseismic data in real time, automatically calculate formation parameters and pressure relief effect indicators, and generate a three-dimensional fracture model.

[0040] This intelligent control and data analysis system achieves a closed loop from command execution to decision support through the collaborative work of a central controller and data analysis and visualization software. The central controller, acting as the hardware hub, establishes real-time signal connections via wired or wireless communication links with the actuators of the high-pressure fracturing and sealing system (such as drive unit 12, expansion unit 13, and high-pressure water pump 22), all sensors of the multi-source information monitoring system (such as pressure sensor 17, distributed optical fiber 3, and micro-seismic array), and the miniature high-pressure sealing capsule 16 of the leakage channel dynamic management system. It receives massive amounts of raw data from the sensors and, based on preset logic or higher-level instructions, precisely sends control commands to coordinate the actions of all hardware units, such as precisely controlling the pressurization rate, pressure holding time, depressurization process, and sealing trigger timing. The data analysis and visualization software, as the core software, performs real-time analysis, fusion, and calculation of multi-source heterogeneous data, including pressure-time data, distributed optical fiber sensor data, and micro-seismic data, collected by the central controller. It incorporates specialized algorithms that can automatically retrieve key parameters such as formation stress and rock strength, and evaluate the stress relief effect in real time based on multi-dimensional indicators (such as stress relief range and stress release rate). Simultaneously, the software transforms abstract monitoring data into intuitive three-dimensional fracture models and dynamic curves, enabling process visualization.

[0041] Exemplarily, the specific implementation of the intelligent control and data analysis system can be adjusted according to the engineering scale and complexity. For example, in a large mine project, the central controller can adopt a combination of high-reliability industrial PLC and industrial computer, and has a redundant design; the data analysis software can be deployed on a cloud server to realize centralized management and remote expert consultation of multiple site data. In general tunnel engineering, an integrated portable integrated box can be used, which has an internal operation unit and a display screen. The weight of the evaluation index in the software, the rendering method of the three-dimensional model, etc. can be customized according to user needs. It should be noted that the above hardware configuration, deployment mode and software function selection are only examples, and any system solution that realizes centralized control, data fusion analysis and visual feedback to guide fracturing operation is within the protection scope of the present application.

[0042] In some embodiments, as shown in Figure 5 The high-pressure pumping unit further includes a base plate 23, the high-pressure water pump 22 is fixedly installed through the base plate 23, the motor 21 provides power for the high-pressure water pump 22, the accumulator is in communication with an output pipeline of the high-pressure water pump 22, and is used for stabilizing the pumping pressure; the position of the fracturing section of the center anchor rod 5 corresponds to the position of the water pressure fracturing outlet 4 and the sealing range of the packer 1, and an independent fracturing section space is formed.

[0043] The high-pressure pumping unit is the core of generating and delivering high-pressure water power. After the motor 21 is started, the high-pressure water pump 22 is driven to work, and the water from the water storage tank 20 is pressurized. The pressurized water flows through the output pipeline, and the accumulator connected in parallel on the pipeline is used to absorb and buffer the pressure pulsation generated in the pumping process, and plays a role of stabilizing the system pressure and ensuring the smoothness of the pressure curve. The high-pressure water is then injected into the internal passage of the center anchor rod 5 through the water delivery pipe 25, and finally sprayed from the water pressure fracturing outlet 4 located in the fracturing section. The key design is that the axial position of the water pressure fracturing outlet 4 is accurately adapted to the sealing range of the intelligent movable double packer unit. When the two packers 1 expand and seal the borehole wall, they just isolate a closed annular space with the water pressure fracturing outlet 4 as the center, that is, an independent fracturing section space. All the pumped high-pressure water is strictly limited in this space to act on the surrounding rock, so as to implement precise fracturing. The high-pressure water pump 22 is firmly fixed through the base plate 23, which ensures the stability and reliability of the whole power equipment under the condition of continuous high-pressure working state.

[0044] Exemplarily, the specific implementation of the high-pressure pump injection unit can be adjusted according to engineering requirements. For example, the structure and fixing method of the base plate 23 can be designed according to the floor conditions of the well site or the tunnel, such as installing a larger base under a soft floor. The volume and response characteristics of the accumulator can be selected and matched according to the target pump injection flow and pressure level. For example, for super-deep hole or super-high pressure working conditions, a multi-stage booster pump or a larger power motor 21 can be used. It should be noted that the above enumeration of component specifications, fixing methods and pressure stabilization specific means are only examples, and any pump injection system design that can achieve stable generation of high-pressure water flow and accurate guidance and limitation to the target fracturing section is within the scope of the principles of the present application.

[0045] In some embodiments, as shown in Figures 1 to 3 The center pipe 10 of the packer 1 is in communication with the water injection channel of the center anchor rod 5, and the sealing ring 11 is arranged at the connection between the center pipe 10 and the rubber sleeve seat 7 to ensure sealing performance. The drive device 12 is used to drive the packer 1 to slide along the slide 14, and the expansion device 13 is used to drive the rubber sleeve 8 to expand to achieve sealing with the borehole wall.

[0046] The above-mentioned intelligent movable double-packer unit is the core executive component for realizing dynamic and accurate sealing function. Its working principle is based on the synergistic effect of mechanical transmission and hydraulic expansion. First, the drive device 12 receives instructions from the intelligent control system, and drives the entire packer 1 unit to slide axially on the precise linear slide 14 of the outer wall of the center anchor rod 5 through its slide block mechanism, so as to accurately move to the target depth position in the borehole. After positioning, the expansion device 13 is activated, and the generated thrust or hydraulic pressure drives the rubber sleeve 8 to expand radially, so as to tightly press the borehole wall and form a reliable annular sealing section in the borehole. The center pipe 10 serves as a channel for high-pressure water flow, one end of which is in communication with the water injection channel of the center anchor rod 5 to ensure that high-pressure water can flow into the sealed chamber without obstruction, and the other end is connected with the internal structure of the packer. The sealing ring 11 arranged at the connection between the center pipe 10 and the rubber sleeve seat 7 blocks the key mechanical connection interface to prevent high-pressure water from leaking from the internal channel to the outside, thereby ensuring the integrity and sealing performance of the entire pressure system from the pump injection unit to the borehole wall.

[0047] Exemplarily, the specific implementation of the packer can be adapted according to the actual working condition. For example, the driving device 12 can be an electric ball screw, a hydraulic cylinder or a linear motor, which is selected according to the requirements for moving speed and positioning accuracy. The expansion device 13 can be a hydraulic piston or a shape memory alloy driver. The material, hardness and structure of the rubber tube 8 (such as whether to contain a reinforcing cord layer) can be optimized according to the drilling diameter, the hole wall roughness and the expected sealing pressure. The type and material of the sealing ring 11 (such as an O-ring, a combined seal, fluororubber or hydrogenated nitrile rubber) also need to match the downhole pressure, temperature and medium conditions. It should be noted that the above specific selection of driving mode, expansion mechanism, rubber tube design and sealing type are examples, and any packer design that can achieve accurate positioning along the guide mechanism and reliable sealing of the drilling hole is within the scope of the principles of the present application.

[0048] Embodiment 2 The embodiment of the present application provides an evaluation method for the pressure relief effect and formation parameters of the water pressure fracturing pressure relief effect and formation parameter integrated detection device as described in embodiment 1 above. As shown in Figure 6 the following four links are carried out in turn: The construction preparation data acquisition link. This link specifically covers the operation of engineering preparation, drilling construction, integrated detection device deployment and data acquisition: first complete the pre-deployment of engineering preparation and drilling construction, then deploy the integrated detection device which integrates high pressure fracturing and sealing system, multi-source information monitoring system, intelligent control and data analysis system to the target position, and then start the related components to carry out data acquisition.

[0049] The ground stress calculation and three-dimensional modeling link. Relying on the initial pressurization, crack propagation, instantaneous pressure, pressure relief and re-tensioning in the high pressure fracturing operation, combined with the information collected in the construction preparation stage, the ground stress calculation and three-dimensional modeling are carried out simultaneously to provide basic data support for subsequent evaluation.

[0050] Multi-index quantitative evaluation link. Based on the results of ground stress calculation and three-dimensional modeling, the pressure relief effect and formation parameters of water pressure fracturing are comprehensively and quantitatively evaluated around the indexes of pressure relief range index, stress release rate, energy dissipation index and crack complexity.

[0051] Effect judgment and decision-making link. According to the results of multi-index quantitative evaluation, the effect is judged: if the evaluation result is up to standard, the operation of parameter solidification and batch promotion is executed; if the evaluation result is not up to standard, the operation of parameter optimization and reinforcement fracturing is executed, so as to form a closed-loop evaluation and optimization mechanism.

[0052] Specifically, as shown in Figure 7 the pressure relief effect and formation parameter integrated evaluation method is implemented by the following steps S1-S6.

[0053] S1, drilling a borehole in a target pressure relief area, lowering an integrated detection device to a preset depth, dynamically selecting and positioning an optimal cracking section according to monitoring data, and performing a sealing operation.

[0054] Specifically, in step S1, in the target pressure relief area, the drilling parameters (hole diameter, depth, orientation) are determined according to the geological survey data. After completing the drilling construction, the integrated detection device, which integrates intelligent movable double packers, central anchor rod slide units, optical fiber sensing arrays and other components, is slowly lowered to the preset cracking depth. According to the rock mass structure information fed back by the downhole acoustic imaging and distributed optical fiber monitoring equipment, the best cracking section with the most complete rock mass and the most concentrated stress is dynamically selected for sealing operation, ensuring that the device closely fits the borehole wall and laying a foundation for subsequent sealing and monitoring operations.

[0055] S2, starting the intelligent movable double packer, isolating an independent cracking section, and recording the initial stable pressure P0.

[0056] Specifically, in step S2, the intelligent movable double packer unit is started and moved to the appropriate fracturing position through the slide. Then the intelligent movable double packer is expanded by hydraulic drive until it is completely sealed with the borehole wall, accurately isolating an independent "cracking section". After the sealing state is stable, the initial stable pressure P0 is recorded by the pressure sensor of the high-pressure pump injection unit. This data serves as a reference value for subsequent ground stress calculation and pressure change analysis, and the accuracy and stability of data acquisition need to be ensured.

[0057] S3, performing pressure cycle operation, and sequentially recording initial fracture pressure Pc, crack propagation pressure Ps, instantaneous closing pressure and crack reopening pressure Pr.

[0058] Specifically, in step S3, pressure cycle operation is carried out according to the classical water pressure fracturing process, and the requirements for each stage operation and data collection are as follows: Initial pressurization stage: high-pressure water is injected into the sealed cracking section at a preset constant flow rate, and the pressure change trend is monitored in real time. As the amount of injected water increases, the pressure in the cracking section continues to rise until the rock mass overcomes its tensile strength and breaks, recording the peak pressure Pc at this time. This pressure reflects the minimum pressure required for the initial fracture of the rock mass.

[0059] Crack propagation and pressure maintenance stage: after the rock mass breaks, the pressure in the cracking section drops sharply due to the formation of crack space, and then stabilizes at a certain constant level, which is the crack propagation pressure Ps. This pressure state is maintained for a certain period of time (determined according to the characteristics of the rock mass and the pressure relief requirements), ensuring that the crack can fully expand along the maximum principal stress direction and form an effective pressure relief channel.

[0060] Instantaneous closure and pressure recording stage: After the fracture is fully expanded, the high-pressure water pump is quickly closed to block the injection of high-pressure water, and the instantaneous closure pressure (approximately equal to the fracture expansion pressure Ps, which is a key parameter for stress calculation) is accurately recorded to capture the instantaneous response of the rock mass under pressure shock.

[0061] Pressure relief and re-tensioning stage: The pressure in the fracturing section is gradually reduced to zero to complete the first round of fracturing; then the high-pressure pump injection unit is restarted for secondary pressurization, and the pressure when the fracture reopens (i.e., the fracture reopening pressure Pr, which is used to invert the initial stress state of the rock mass) is recorded.

[0062] S4, based on the pressure data collected in steps S2 and S3, calculate the maximum and minimum horizontal principal stresses of the stratum; at the same time, fuse multi-source monitoring data to build a three-dimensional fracture model of the fracturing area.

[0063] Specifically, in step S4, based on the collected pressure data and rock mass mechanical parameters, the following formula is used to carry out geostress calculation: Maximum horizontal principal stress σ H : where T is the tensile strength of the rock, σ h is the minimum horizontal principal stress, approximately equal to Ps, P0 is the initial stable pressure, and Pr is the fracture reopening pressure. The fracture dominant direction located by fiber sensing or microseismic event positioning determines the direction of the maximum horizontal principal stress.

[0064] A multi-data fusion technique is used to build a three-dimensional fracture model of the fracturing area: taking the distributed fiber sensing data in the well as the core, its high spatial resolution can accurately locate the fracture initiation point, expansion path and near-field details (such as fracture width and branching); supplemented by microseismic monitoring data outside the hole, the range and spatial form of the far-field fracture network are outlined through the three-dimensional coordinate distribution of microseismic events; finally, with the help of professional visualization software, the two types of data are spatially matched and integrated to generate a three-dimensional digital model containing parameters such as fracture location, orientation, length and density, and the fracturing effect is intuitively presented.

[0065] S5, based on the three-dimensional fracture model and monitoring data, quantitatively evaluate from multiple dimensions such as pressure relief range index, stress release rate, energy dissipation index and fracture complexity to obtain the pressure relief effect index.

[0066] The purpose of step S5 is to establish a scientific and comprehensive evaluation index system to quantify the pressure relief effect from different dimensions and ensure the objectivity and practicality of the evaluation results.

[0067] Pressure relief range index: Based on the three-dimensional fracture model, combined with the engineering requirements of the target pressure relief area (such as protecting the roadway, controlling rock burst, etc.), the extension radius of the induced fracture in the key direction (such as towards the goaf, the head-on roadway) is calculated, and the rock volume covered by the fracture network (i.e. the influence volume) is also calculated. This index directly reflects the spatial coverage of the pressure relief effect, and needs to meet the requirements of the preset protection radius and influence volume.

[0068] Stress release rate is calculated using the stress data before and after fracturing collected by the borehole stress meter in the adjacent observation hole through the following formula: where ω is the stress release rate, σ before is the initial stress of the rock mass before fracturing, σ after is the residual stress of the rock mass after stable fracturing. The higher the stress release rate, the more sufficient the release of the elastic potential energy accumulated in the rock mass, and the more significant the pressure relief effect. Usually, it needs to reach more than 30% (the specific threshold is determined according to the engineering risk level).

[0069] For the energy dissipation index, the pressure relief effect is evaluated from the energy perspective. On the one hand, the total energy (i.e. injection work) injected by the high-pressure pump during the entire fracturing process is calculated by integrating the P-t curve and flow data. On the other hand, the total energy released by rock fracture is converted from the microseismic event magnitude recorded by the microseismic monitoring system. By analyzing the ratio of released energy to injected energy, the energy conversion efficiency is evaluated. If the released energy accounts for a high proportion, it means that the injected energy is effectively used for rock fracture and pressure relief, and the energy utilization efficiency is good. Otherwise, the pump injection parameters need to be optimized to reduce energy loss.

[0070] For the fracture complexity, the complexity of the fracture network is quantified in two ways: one is to calculate the fractal dimension of the point cloud data formed by the microseismic events. The higher the fractal dimension, the more abundant the fracture branches and the denser the network. The second is to analyze the fluctuation frequency and amplitude of the optical fiber sensing signal. The more abundant the signal (such as more strain mutation points and wider frequency band of acoustic signals), the more sufficient the fracture development. Generally, the higher the fracture complexity, the more dispersed the stress transmission path in the rock mass, and the better the stability of the rock mass after pressure relief, which can effectively reduce the risk of rock burst, water inrush and other disasters.

[0071] S6, compare the pressure relief effect index with the preset target. If it meets the standard, solidify the current fracturing parameters for subsequent operations. If it does not meet the standard, analyze the reasons and adjust the fracturing parameters accordingly to optimize or reinforce the fracturing.

[0072] Specifically, in step S6, the pressure relief effect evaluation result is fed back to the engineering control center in real time, and the engineer comprehensively judges in combination with the preset target (such as the pressure relief range and the stress release rate threshold). If all evaluation indexes meet the expectation, it indicates that the current fracturing parameters (pumping pressure, flow rate, pressure maintaining time, and sealing position) are suitable for the target regional geological conditions, and the subsequent batch pressure relief operation can be carried out according to the parameters. If one or more indexes do not meet the standard (such as insufficient pressure relief range and too low stress release rate), the causes (such as limited fracture expansion due to low pumping pressure and improper fracturing section selection due to sealing position deviation) are immediately analyzed, and the fracturing parameters (such as increasing pumping pressure, prolonging pressure maintaining time, and optimizing sealing depth) are adjusted in the unfractured section of the same borehole or in the adjacent supplementary borehole to carry out “reinforcement” fracturing operation. Through the closed-loop control mechanism of detection-evaluation-decision-optimization, the construction scheme is continuously optimized to ensure that the final pressure relief effect meets the engineering safety and production requirements.

[0073] Based on the mechanism principle of the method as described above, a specific example will be described in detail below. The method can be implemented through the following four steps in specific implementation.

[0074] Step one, the working face of a certain coal mine is 850 m deep, the main coal seam is 3.2 m thick, the pre-advance abutment pressure concentration coefficient is 2.8, microseismic events frequently occur (the maximum magnitude is 1.5), and there is a risk of rock burst. In order to ensure the safety of mining, the water pressure fracturing pressure relief technology is used, and the core target is: the pressure relief influence radius is not less than 5 m, the stress release rate is not less than 30%, the microseismic frequency is reduced by more than 50%, and an effective pressure relief fracture network is constructed. According to the geological survey, the maximum horizontal principal stress direction of the working face is N45°E, three fracturing boreholes (Z1-Z3) are constructed in the transportation roadway, the borehole diameter is 90 mm, the borehole depth is 50 m, and the direction is perpendicular to the advancing direction of the working face. The device of the intelligent movable packer, the distributed optical fiber sensing array and the pressure / flow rate sensor is lowered, the packer is positioned at the 25-27 m section of the borehole (the stress concentration core area) through the detection result, and it is ensured that the equipment is attached to the borehole wall and the signal transmission is normal.

[0075] Step two, the packer drive system and the inflation system are started, and the packer starts to inflate and completely seals with the borehole wall. After 30 minutes of sealing state stabilization, the initial stable pressure P0=2.3 MPa is recorded by the pressure sensor, which is used as the reference for subsequent ground stress calculation and pressure change analysis, and provides an initial reference for accurate evaluation of the fracturing process.

[0076] Step 3 employs an initial pressurization-fracture propagation-instantaneous closure-depressurization and re-opening cycle: water is injected at a constant flow rate of 15 L / min, and the rock mass fractures when the pressure reaches 38.6 MPa (Pc=38.6 MPa); subsequently, the pressure is stabilized at 16.8 MPa (Ps=16.8 MPa) and maintained for 40 minutes; the pump is then shut off, and the instantaneous pressure of 16.5 MPa is recorded. After depressurization to zero, pressure is restored, and the fracture reopens at 22.3 MPa (Pr=22.3 MPa). PtQ curves, fiber optic fracture data, and data from 23 microseismic events are simultaneously acquired. In-situ stress and the fracture generation model are also calculated.

[0077] Step 4, Effect Evaluation: In terms of the pressure relief range, the critical direction expansion radius is 6.2m, exceeding the 5m target; regarding the stress release rate, the adjacent observation wells show the pre-fracture stage. σ before =32.5MPa, after σ after =21.2MPa, release rate 34.8%, exceeding the 30% threshold; energy conversion efficiency 40.6% (1280kJ injected, 520kJ released); fracture network fractal dimension 1.82, 12 strain abrupt change points monitored by optical fiber, fully developed.

[0078] Feedback optimization: The Z1 borehole met the standards, the Z2 borehole continued to use the same parameters (flow rate 15 L / min, pressure holding time 40 min), and the Z3 borehole, due to a local thinning of 0.3 m in the coal seam, had its pressure holding time extended to 45 min. Ultimately, the stress release rates of the two boreholes reached 36.2% and 35.5%, respectively. One month after fracturing, the frequency of micro-vibrations in the advanced area of ​​the working face decreased from an average of 12 times per day to 4 times, with no signs of rockburst.

[0079] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the present invention, and the patent protection scope of the present invention should be defined by the claims.

Claims

1. A water pressure fracturing pressure relief effect and formation parameter integrated detection device, characterized in that, The system comprises a high-pressure fracturing and sealing system, a multi-source information monitoring system, a leakage channel dynamic management system and an intelligent control and data analysis system. The high-pressure fracturing and sealing system is used for adaptive sealing and high-pressure hydraulic fracturing at a target fracturing section in a borehole. The multi-source information monitoring system is used for real-time collection of multi-source information in and outside the well during the fracturing process. The leakage channel dynamic management system is integrated on the high-pressure fracturing and sealing system. The intelligent control and data analysis system is electrically connected with the high-pressure fracturing and sealing system and the multi-source information monitoring system, and is used for receiving and processing monitoring data, controlling the fracturing process, and real-time calculation of formation parameters and evaluation of pressure relief effect.

2. The hydraulic fracturing pressure release effect and formation parameter integrated detection device according to claim 1, characterized in that, The high-pressure fracturing and sealing system comprises a central anchor rod slide unit, an intelligent movable double packer unit, a high-pressure pump injection unit and a guide fracture initialization unit. The central anchor rod slide unit comprises a central anchor rod with a high-strength hollow structure, the outer wall of the central anchor rod is provided with a precise linear slide, a sensing optical cable is pre-buried in the anchor rod wall of the central anchor rod, and the central anchor rod has the functions of supporting transmission and water injection channel. The intelligent movable double packer unit comprises two independently controlled packers, the packer is provided with a rubber sleeve seat, a rubber sleeve, a central tube, a sealing ring, a driving device and an expansion device, the packer is engaged with the slide to realize axial precise sliding, and the rubber sleeve is integrated with a micro sensor to realize real-time monitoring of the sealing state. The high-pressure pump injection unit comprises a water storage tank, a motor, a high-pressure water pump, a flow meter, a pressure sensor and an accumulator, the water storage tank is connected with the high-pressure water pump through a water delivery pipe, the output end of the high-pressure water pump is communicated with the water injection channel of the central anchor rod, the fracturing section of the central anchor rod is provided with a water pressure fracturing outlet, and the pressure sensor and the flow meter are signal connected with the intelligent control and data analysis system. The guide fracture initialization unit is integrated on the fracturing section of the central anchor rod and adopts controllable directional perforation technology, and the two ends of the central anchor rod are respectively provided with an upper interface and a lower interface for realizing assembly of components and connection of pipelines.

3. The hydraulic fracturing pressure release effect and formation parameter integrated detection device according to claim 2, characterized in that, The leakage channel dynamic management system comprises a plurality of micro high-pressure sealing capsules, the micro high-pressure sealing capsules are arranged on the central anchor rod of the central anchor rod slide unit and located outside the sealing range of the intelligent movable double packer unit, and the micro high-pressure sealing capsules are signal connected with the intelligent control and data analysis system.

4. The hydraulic fracturing pressure release effect and formation parameter integrated detection device according to claim 2, characterized in that, The multi-source information monitoring system comprises an in-well monitoring unit and an out-of-hole monitoring unit, the in-well monitoring unit comprises a distributed optical fiber sensing array and a downhole television / sonic probe, the distributed optical fiber sensing array is composed of distributed optical fibers arranged along the borehole wall or the outer wall of the packer, and the sonic probe is used for imaging the borehole wall before and after fracturing, the out-of-hole monitoring unit comprises a microseismic monitoring array and a borehole stress meter, the microseismic monitoring array is arranged around the fracturing borehole and used for capturing microseismic events caused by fracture expansion, and the borehole stress meter is installed in a neighboring observation hole and used for monitoring stress changes of the surrounding rock mass during pressure relief, and the distributed optical fiber, the sonic probe, the microseismic monitoring array and the borehole stress meter are signal connected with the intelligent control and data analysis system.

5. The apparatus according to claim 1, wherein, The high-pressure pump injection unit further comprises a base plate, the high-pressure water pump is fixedly installed through the base plate, the motor provides power for the high-pressure water pump, the accumulator is communicated with an output pipeline of the high-pressure water pump, and is used for stabilizing pump injection pressure; a position of the fracturing section of the central anchor rod corresponding to a water outlet of water pressure fracturing is adapted to a sealing range of the packer, and an independent fracturing section space is formed.

6. A method for evaluating the pressure relief effect of the device according to any one of claims 1-5 in combination with formation parameters, characterized in that, The method comprises the following steps: S1, drilling a hole in a target pressure relief area, lowering an integrated detection device to a preset depth, dynamically selecting and positioning an optimal fracturing section according to monitoring data, and performing a sealing operation; S2, starting an intelligent movable double packer to isolate an independent fracturing section, and recording an initial stable pressure P0; S3, performing a pressure cycle operation, and sequentially recording an initial fracture pressure Pc, a fracture propagation pressure Ps, an instantaneous closing pressure, and a fracture reopening pressure Pr; S4, calculating a maximum horizontal principal stress and a minimum horizontal principal stress of the stratum based on pressure data collected in steps S2 and S3, and simultaneously, constructing a three-dimensional fracture model of the fracturing area by fusing multi-source monitoring data; S5, based on the three-dimensional fracture model and the monitoring data, performing quantitative evaluation from multiple dimensions of a pressure relief range index, a stress release rate, an energy dissipation index, and a fracture complexity to obtain a pressure relief effect index; S6, comparing the pressure relief effect index with a preset target, if the target is met, solidifying the current fracturing parameters for subsequent operations, if the target is not met, analyzing the reasons and adjusting the fracturing parameters accordingly to optimize or reinforce fracturing.

7. The method of claim 6, wherein, In step S4, the maximum horizontal principal stress is calculated σ H The formula is: where T is the rock tensile strength, σ h is the minimum horizontal principal stress, equal to Ps.

8. The method of claim 6, wherein, In step S5, the calculation formula of the stress release rate is: where ω is the stress release rate, σ before is the initial stress of the rock mass before fracturing, σ after is the residual stress of the rock mass after fracturing.

9. The method of claim 6, wherein, The energy dissipation index is evaluated by the following way: calculating the total energy injected by the high-pressure pump injection unit in the entire fracturing process and the total energy released by rock mass fracture through microseismic event magnitude conversion, analyzing the ratio of the two to evaluate the energy conversion efficiency; The quantitative method of the fracture complexity includes: calculating the fractal dimension of the microseismic event point cloud data, and / or analyzing the fluctuation frequency and amplitude of the strain or acoustic signals collected by the distributed optical fiber sensing array.

10. The method of claim 6, wherein, The pressure cycle operation in step S3 specifically comprises: An initial pressurization stage: injecting water at a constant flow rate, the pressure rises to the rock mass fracture, and the peak pressure is recorded; A fracture propagation and pressure maintaining stage: keeping the pressure at the fracture propagation pressure level and maintaining for a set time; An instantaneous closing and pressure recording stage: quickly closing the high-pressure water pump, and recording the instantaneous closing pressure; A pressure relief and reopening stage: after the pressure is reduced to zero, the pressure is re-increased to the fracture reopening, and the reopening pressure is recorded.

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