Stress energy double-compensation tough anchor cable and supporting method

Abstract

The invention discloses a stress energy double-compensation tough anchor cable and a supporting method, and belongs to the technical field of mine supporting. Comprising a steel strand, an intelligent anchoring head, a graded energy absorption unit, an energy compensation bin and a self-locking anchor tail module, the graded energy absorption unit is formed by axially connecting a buckling induction energy consumption layer, a variable friction damping module and a hydraulic negative stiffness mechanism in series, and the energy compensation bin is communicated with an intelligent nozzle through an intelligent distributor and a grouting pipe. The supporting method comprises five steps of closed-loop control: geologically adaptive anchoring to construct a low-stress field; the third-stage time sequence dissipates impact energy; injecting a phase change expansion material in a targeted manner based on real-time monitoring; surrounding rock-support cooperation is maintained through periodic excitation; and the dynamic optimization threshold value realizes long-acting stability. By means of a multi-physical-field coupling mechanism, the three bottleneck problems that a traditional support is insufficient in impact resistance, mismatched in energy dissipation and lagged in stress compensation are solved, and the deep mine rock burst prevention and treatment efficiency is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of mine support, in particular to a stress-energy dual-compensation toughness anchor cable and a support method. Background Art

[0002] As mining depths continue to increase, deep rock masses are showing significant impact tendencies under high ground stress and strong mining disturbances. The essence of rock burst disasters is that the elastic energy accumulated in the surrounding rock is released violently in a short period of time, leading to instability of the support structure and collapse of the roadway. Existing support technologies have three major bottlenecks:

[0003] (1) Structural flaws in impact resistance: Traditional anchor cables rely excessively on strategies to improve material strength, such as simply increasing the ultimate strength of steel strands. This type of design cannot adapt to the unique instantaneous characteristics of impact loads, and its millisecond-level action time scale creates a fundamental contradiction with its strong dynamic characteristics. There is a significant order of magnitude difference between static design indicators such as tensile strength and dynamic impact response. Actual measurements show that when the strain rate exceeds 100 per second, the anchor cable bearing capacity attenuation rate is as high as 60%.

[0004] (2) Mismatch between energy dissipation mechanism and surrounding rock release: Conventional energy absorption devices generally use a single threshold trigger mechanism. For example, friction dampers can only be activated at a fixed critical force. This seriously restricts their adaptability to the time-varying characteristics of surrounding rock energy release. Monitoring data of rock burst events in deep mines show that the energy release process exhibits typical multi-peak oscillation characteristics, with a duration generally ranging from 300 to 800 milliseconds. Existing devices are unable to dynamically adjust energy consumption intensity, resulting in an actual energy consumption efficiency of less than 40%, and a large amount of residual energy continues to damage the support system.

[0005] (3) The temporal and spatial hysteresis of stress compensation: In the secondary stress field formed by tunnel excavation, the energy density of the high-energy zone of the surrounding rock generally exceeds 10,000 joules per cubic meter. Existing technologies mainly rely on passive grouting reinforcement and lack the ability to actively intervene in the energy accumulation process. The curing time of the grouting material usually takes tens of minutes, which makes it impossible to achieve real-time transfer and energy rebalancing in the stress concentration zone. This hysteresis makes the support system always in a passive state of energy defense.

[0006] At the same time, there is a disconnect between monitoring and control in the current field of rock burst prevention and control. Although the microseismic monitoring system can capture energy accumulation signals, it has failed to establish an effective linkage with the dynamic response of the support system. In addition, the energy interaction mechanism between the support structure and the surrounding rock is still insufficiently studied, resulting in the design theory failing to break through the framework constraints of static mechanics. Although the excavation compensation method proposed by the international academic community has the foresight of the stress transfer concept, its engineering implementation relies on large-scale pressure relief projects, such as blasting or drilling pressure relief. Such methods not only have a construction period of several weeks, but also seriously damage the integrity of the original structure of the surrounding rock, forming new weak zones and exacerbating long-term rheological risks. Therefore, the industry urgently needs to develop an active control technology that integrates the three functions of dynamic energy absorption, adaptive stress regulation, and real-time energy compensation to fundamentally solve the core problem of insufficient anti-shock and seismic capacity of deep mine support systems. Summary of the Invention

[0007] The purpose of the present invention is to provide a stress-energy dual-compensation tough anchor cable and support method, which solves the problem of overall failure of traditional anchor cables due to brittle fracture under impact loads; breaks through the adaptability limitations of existing energy absorption devices to multi-frequency and variable amplitude impact energy; and establishes a real-time feedback and compensation control mechanism for the stress-energy evolution of the surrounding rock.

[0008] To achieve the above objectives, the present invention provides a stress-energy dual-compensation ductile anchor cable, comprising a steel strand with a guide head and an intelligent anchor head fixed to the front end of the strand. The strand is provided with a bearing plate connected to the intelligent anchor head. A graded energy absorption unit, an energy compensation chamber, and a self-locking anchor tail module are sequentially arranged along the axial direction of the strand. The graded energy absorption unit includes a buckling-inducing energy dissipation layer, a variable friction damping module, and a hydraulic negative stiffness mechanism. The buckling-inducing energy dissipation layer, the variable friction damping module, and the hydraulic negative stiffness mechanism are sequentially connected along the axial direction of the strand. The intelligent anchor head is equipped with a piezoelectric ceramic sensor array capable of sensing surrounding rock stress fluctuations in real time (resolution ±0.1 MPa). The energy compensation chamber stores nanocomposite gel and magnetic particles, whose injection is controlled by a micro-electromagnetic valve. The self-locking anchor tail adopts a bidirectional ratchet structure to ensure that the preload loss rate after impact is less than 5%.

[0009] Preferably, the guide head is a conical structure, with its small diameter end fixedly connected to the end of the steel strand and its large diameter end fitted with the end face of the intelligent anchoring head. The bearing plate is a circular plate structure with a through hole in the center for the steel strand to pass through. One side of the bearing plate is in contact with the end face of the intelligent anchoring head, and the other side of the bearing plate is connected to the buckling-inducing energy dissipation layer.

[0010] Preferably, the energy compensation chamber includes a sleeve, which is divided into a gel storage chamber and a magnetic particle chamber by a partition. The outside of the magnetic particle chamber is surrounded by an excitation coil 2. The gel storage chamber is connected to an intelligent distributor. The intelligent distributor is connected to a grouting pipe, and an intelligent nozzle is provided at the end of the grouting pipe.

[0011] Preferably, the buckling-inducing energy dissipation layer is a Cr-Ni alloy bellows, one end of which is connected to the bearing plate and the other end to the variable friction damping module. The Cr-Ni alloy bellows has a yield strength of 600 MPa and a pre-compression of 20 mm. When the impact stress wave amplitude first exceeds 50 MPa, the bellows undergoes axial buckling deformation, absorbing approximately 30% of the initial impact energy through plastic dissipation while reducing the stress wave rise slope.

[0012] Preferably, the variable friction damping module comprises a titanium alloy sleeve with a shape memory alloy friction plate on its inner wall. Involute grooves are designed on the inner wall of the titanium alloy sleeve. The SMA friction plate undergoes an austenitic phase transformation under the impact of temperature rise, driving the plate to expand radially. The friction coefficient changes dynamically with temperature: from 0.25 at room temperature to 0.55 at 150°C, achieving a strain rate enhancement effect and dissipating 40% of the mid-frequency energy.

[0013] Preferably, the hydraulic negative stiffness mechanism includes an excitation coil 1, a silicone oil-based magnetorheological fluid and a composite magnetic shielding sleeve. The composite magnetic shielding sleeve encapsulates the silicone oil-based magnetorheological fluid. The magnetic shielding baffle is provided at one end of the excitation coil 1 close to the smart anchor head. The magnetic shielding baffle is an annular structure made of nickel-iron alloy material. Its inner diameter is in clearance with the steel strand, and its outer diameter is in interference fit with the graded energy absorption unit. When the control system detects that the stress wave frequency is greater than 100 Hz, an axial magnetic field is applied to make the magnetorheological fluid flow at 10 -3 It switches from the solid state to the shear-thinning state within s, producing a negative stiffness effect, offsetting the remaining 30% of the high-frequency impact energy.

[0014] Preferably, the self-locking anchor tail module includes an isolation ring, which is connected to the tail of the steel strand, and a wire racking ring is sleeved on the surface of the steel strand.

[0015] The present invention provides a stress-energy dual-compensation ductile anchor cable support method, comprising the following steps:

[0016] S1. Drill anchor holes in the target area and implant the anchor system to create an initial low-stress field through pre-tightening force.

[0017] S2, sequentially dissipating the impact energy through graded energy absorption units, including sequentially activating three-level energy dissipation mechanisms: buckling-induced energy dissipation, temperature-sensitive friction adaptation, and magnetic field-controlled rheology;

[0018] S3. Based on the real-time monitoring of the surrounding rock energy state, a compensation material with phase change expansion characteristics is injected into the energy accumulation area;

[0019] S4. Maintaining the surrounding rock-support synergistic system through periodic physical field excitation and material self-repair;

[0020] S5. Optimize control thresholds based on dynamic monitoring parameters to achieve long-term stability.

[0021] Preferably, in step S2, the three-level energy consumption mechanism includes the following three stages, as follows:

[0022] S21, buckling-induced energy dissipation stage: When the impact stress wave reaches the first intensity threshold, the buckling-induced energy dissipation layer undergoes axial plastic deformation, prolonging the stress wave action time and absorbing the initial impact energy.

[0023] S22, temperature-sensitive friction adaptive stage: The temperature rise caused by repeated expansion of the surrounding rock triggers the dynamic enhancement of the friction coefficient of the variable friction damping module, dissipating the medium-frequency energy and suppressing the expansion acceleration;

[0024] S23. For high-frequency residual stress waves, the intelligent fluid of the hydraulic negative stiffness mechanism is switched in rheological state through magnetic field excitation, generating a negative stiffness effect to offset the residual energy.

[0025] Preferably, in step S3, the compensation control logic of injecting the compensation material is specifically as follows:

[0026] S31. Energy hotspot diagnosis: Monitor the strain energy density of the surrounding rock through a distributed sensor network and locate the energy accumulation area when it exceeds a preset threshold;

[0027] S32, smart material injection: Inject composite gel material into the target area, using the surrounding rock environment to trigger its phase change expansion to generate radial support pressure;

[0028] S33. Energy-stress rebalance: The expansion pressure drives the redistribution of the surrounding rock stress field, while the alternating magnetic field excites the magnetic particles to convert mechanical energy into heat energy for continuous dissipation.

[0029] Preferably, in step S3, the present invention realizes energy-stress coordinated regulation through three stages:

[0030] (1) Energy monitoring stage

[0031] The distributed fiber Bragg grating sensor monitors the surrounding rock strain energy density U at a sampling rate of 10kHz when:

[0032]

[0033] Where U is the strain energy density per unit volume (unit: kJ / m 3), characterizing the elastic deformation energy accumulated in the surrounding rock;

[0034] σ ij is the surrounding rock stress tensor (unit: MPa), subscripts i, j = 1, 2, 3 represent the three-dimensional spatial components, including normal stress and shear stress;

[0035] ε ij is the surrounding rock strain tensor (dimensionless), directly measured by the fiber Bragg grating sensor;

[0036] U th Energy compensation trigger threshold (experimental calibration value 2.5kJ / m 3 ).

[0037] (2) Material injection stage

[0038] A nano-SiO2 / epoxy resin composite gel (380% expansion ratio) is injected into the surrounding rock using an intelligent distributor to lock onto energy hotspots. Four intelligent nozzles near the surrounding rock fissures are then controlled to inject the composite gel, achieving targeted grouting. The gel undergoes a cross-linking reaction at surrounding rock temperatures (>40°C), expanding fourfold in volume within 60 seconds and generating a high expansion pressure of 8 MPa, squeezing the cracks and transferring stress.

[0039] (3) Dynamic dissipation stage:

[0040] The external alternating magnetic field drives the Fe3O4 magnetic particles to move in a directional manner in the gel matrix, converting the residual mechanical energy into thermal energy through hysteresis loss, with a continuous energy consumption of 120W / m.

[0041] Preferably, the present invention is based on a control method for energy balance, which is specifically as follows:

[0042] (1) Energy state evaluation equation:

[0043]

[0044] Among them, E accumulated is the accumulated net energy, with positive values ​​indicating energy accumulation and negative values ​​indicating dissipation; σ is the principal stress of the surrounding rock, taking the maximum value of the three principal stresses; is the strain rate, that is, the rate of change of strain with time p is the support reaction force, which is generated by the coupling of the anchor cable preload and the surrounding rock deformation; ΔV is the surrounding rock expansion volume, which refers to the volume expansion of the surrounding rock per unit length of the tunnel; η is the damping coefficient of the anchor cable system.

[0045] (2) Multi-threshold decision-making condition formula group:

[0046]

[0047] in, is the energy accumulation rate; is the stress gradient, is the strain acceleration, Indicates that the impact is imminent; U peak is the peak value of strain energy density during the monitoring period.

[0048] Therefore, the present invention adopts a stress-energy dual-compensation toughness anchor cable and support method of the above structure, which has the following beneficial effects:

[0049] (1) The present invention achieves full-cycle coverage of millisecond-level response to impact energy through axially serially connected flexural plastic deformation layers, temperature-sensitive friction adaptive modules, and magnetically controlled negative stiffness mechanisms, thus overcoming the problem of brittle fracture of traditional anchor cables under dynamic loads.

[0050] (2) Based on the real-time monitoring of the surrounding rock energy state, the present invention triggers the intelligent grouting system to inject phase change expansion materials in a targeted manner, and simultaneously uses the alternating magnetic field to drive the magnetic particles to continuously consume energy, thus breaking through the bottleneck of stress compensation lag and residual energy accumulation.

[0051] (3) The present invention integrates periodic physical field excitation, interface self-repair and dynamic threshold optimization to build an adaptive balance of the surrounding rock-support system, completely replacing artificial pressure relief projects and ensuring safe mining in kilometer-deep wells.

[0052] (4) The present invention breaks through the limitation of the single threshold trigger of the existing energy absorption device, and can dynamically adjust the energy consumption intensity according to the time-varying characteristics of the surrounding rock energy release, greatly improving the dissipation efficiency of multi-frequency and variable amplitude impact energy, and avoiding the continuous damage of a large amount of residual energy to the support system.

[0053] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a schematic diagram of the anchor cable structure of a stress-energy dual-compensation toughness anchor cable and support method of the present invention;

[0055] Figure 2 This is a schematic diagram of the working principle of a stress-energy dual-compensation tough anchor cable and support method of the present invention;

[0056] Figure 3 This is a schematic diagram of the cross-sectional structure of an isolation ring of a stress-energy dual-compensation toughness anchor cable and support method of the present invention;

[0057] Figure 4 This is a schematic diagram of anchor cable installation for a stress-energy dual-compensation tough anchor cable and support method of the present invention;

[0058] Reference numerals

[0059] 1-steel strand; 2-intelligent anchor head; 3-bearing plate; 4-Cr-Ni alloy bellows; 5-titanium alloy sleeve; 6-SMA friction plate; 7-magnetic shielding partition; 8-excitation coil one; 9-silicone oil-based magnetorheological fluid; 10-composite magnetic shielding sleeve; 11-excitation coil two; 12-magnetic particle cavity; 13-partition; 14-sleeve; 15-gel storage cavity; 16-intelligent distributor; 17-wire ring; 18-isolation ring; 19-grouting pipe; 20-intelligent nozzle; 21-guide head; 101-coal seam; 102-tunnel; 103-anchor cable; 104-drilling hole. DETAILED DESCRIPTION

[0060] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0061] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0062] Example

[0063] like Figure 1-4 As described above, the present invention provides a stress-energy dual-compensation tough anchor cable, comprising a steel strand 1, a guide head 21 and an intelligent anchor head 2 fixed to the front end of the steel strand 1, a bearing plate 3 connected to the intelligent anchor head 2 is sleeved on the steel strand 1, and a graded energy absorption unit, an energy compensation chamber and a self-locking anchor tail module are sequentially arranged along the axial direction of the steel strand 1; the graded energy absorption unit includes a buckling-inducing energy dissipation layer, a variable friction damping module and a hydraulic negative stiffness mechanism; and the buckling-inducing energy dissipation layer, the variable friction damping module and the hydraulic negative stiffness mechanism are sequentially connected along the axial direction of the steel strand 1. Among them, the guide head 21 is a conical structure, the small diameter end of which is fixedly connected to the end of the steel strand 1, and the large diameter end of which is in contact with the end face of the intelligent anchor head 2, the bearing plate 3 is a circular plate-like structure, the center of which is provided with a through hole for the steel strand 1 to pass through, one side of the bearing plate 3 is in contact with the end face of the intelligent anchor head 2, and the other side of the bearing plate 3 is connected to the buckling-inducing energy dissipation layer.

[0064] The energy compensation chamber includes a sleeve 14, which is divided into a gel storage chamber 15 and a magnetic particle chamber 12 by a partition 13. The outside of the magnetic particle chamber 12 is surrounded by an excitation coil 11. The gel storage chamber 15 is connected to the intelligent distributor 16, and the intelligent distributor 16 is connected to the grouting pipe 19. The end of the grouting pipe 19 is provided with an intelligent nozzle 20.

[0065] The self-locking anchor tail module includes an isolation ring 18 , which is connected to the tail of the steel strand 1 , and a stringing ring 17 is sleeved on the surface of the steel strand 1 .

[0066] The buckling inducing energy dissipation layer is a Cr-Ni alloy bellows 4 , one end of which is connected to the bearing plate 3 , and the other end is connected to the variable friction damping module.

[0067] The variable friction damping module comprises a titanium alloy sleeve 5 , the inner wall of which is provided with a shape memory alloy friction plate 6 .

[0068] The hydraulic negative stiffness mechanism includes an excitation coil 8, a silicone oil-based magnetorheological fluid 9 and a composite magnetic shielding sleeve 10. The composite magnetic shielding sleeve 10 encapsulates the silicone oil-based magnetorheological fluid 9. A magnetic shielding partition 7 is provided at one end of the excitation coil 8 close to the intelligent anchoring head 2. The magnetic shielding partition 7 is an annular structure and is made of nickel-iron alloy material. Its inner diameter is clearance-fitted with the steel strand 1, and its outer diameter is interference-fitted with the graded energy absorption unit.

[0069] The present invention provides a stress-energy dual-compensation ductile anchor cable support method, comprising the following steps:

[0070] S1. Drill anchor holes 104 in the target area and implant anchor cables 103 to create an initial low stress field through pre-tightening force.

[0071] S2, sequentially dissipating the impact energy through graded energy absorption units, including sequentially activating three-level energy dissipation mechanisms: buckling-induced energy dissipation, temperature-sensitive friction adaptation, and magnetic field-controlled rheology;

[0072] S3. Based on the real-time monitoring of the surrounding rock energy state, a compensation material with phase change expansion characteristics is injected into the energy accumulation area;

[0073] S4. Maintaining the surrounding rock-support synergistic system through periodic physical field excitation and material self-repair;

[0074] S5. Optimize control thresholds based on dynamic monitoring parameters to achieve long-term stability.

[0075] Figure 4This diagram illustrates the anchor cable installation process, showing the spatial deployment of the anchor cable within the surrounding rock of a coal mine roadway and the positional relationships of the structural components. The diagram focuses on the spatial positioning of the anchor cable installation, its interaction with the surrounding rock, and the stress transfer mechanism. The coal seam 101 lies beneath the roadway 102, and the anchor cable 103 is installed perpendicular to the roof. The anchor cable 103 penetrates the roof rock and is inserted into a drill hole 104.

[0076] Specifically, the present invention is applied in a practical scenario, and the specific steps are as follows:

[0077] S1. Geologically Adaptable Anchoring and Low-Energy Stress Field Construction: Based on geostress inversion results, anchor holes 104 with a diameter of 72 mm and an inclination of 22° were drilled 11.8 m deep in a high-impact sandstone tunnel 102 buried at a depth of 1,320 m. Following borehole formation, a nano-silicon-aluminum-based pretreated slurry was injected. Within 8 minutes, the slurry penetrated cracks ≥ 0.2 mm in diameter, forming an enhanced stress transfer network. During anchor cable 103 implantation, the 32-element piezoelectric ceramic sensor in the intelligent anchor head 2 monitored the pressure distribution of the resin anchor in real time. The tensioning process was initiated when the pressure gradient reached ≤ 0.4 MPa / m. The preload force was applied to 280 kN through hydraulic graded loading (80 kN / stage). The bidirectional helical ratchet of the self-locking anchor tail precisely engaged the spiral notches on the surface of the steel strand, reducing the stress concentration factor of the roof from the initial 4.5 to 2.0 and the surface displacement rate of tunnel 102 from 0.25 mm / h to 0.07 mm / h, thus creating a low-energy surrounding rock environment.

[0078] S2. Impact energy dissipation and dynamic stress wave reconstruction: Strong mining on the working face induces rock burst with a peak energy of 253kJ. The stress wave reaches the anchor cable system at a speed of 380m / s.

[0079] 0-48ms (first-level buckling energy dissipation): The 78MPa stress peak triggers the axial buckling of the Cr-Ni bellows. The corrugation valley spacing is compressed from 12mm to 2.3mm, resulting in 21.7% plastic strain. 58.2kJ of energy (23% of the total) is dissipated through dislocation multiplication, extending the stress wave rise time from 18ms to 32ms.

[0080] 48-235ms (secondary friction adaptation): The repeated expansion of the surrounding rock causes the temperature of the variable friction module to rise to 162°C, the austenite phase transformation completion rate of the SMA friction plate is 95%, the radial expansion is 1.8mm, the friction coefficient is dynamically increased to 0.61, and 36.8kJ of energy (accounting for 14.6% of the total) is consumed, suppressing the acceleration of the surrounding rock expansion to 3.8s -2 ;

[0081] 235-530ms (three-level negative stiffness peak clipping): The microprocessor recognizes the 128Hz high-frequency residual wave, and the 0.92T axial magnetic field excites the shear thinning of the magnetorheological fluid within 4ms, achieving stiffness switching from +5.2GN / m to -2.1GN / m, and the residual stress wave amplitude is attenuated to below 10MPa (energy attenuation rate 83%).

[0082] S3. Energy hotspot diagnosis and targeted stress compensation: 545ms after the impact, the distributed fiber optic sensor network locates the energy accumulation hotspot, and the decision-making system performs coordinated intervention:

[0083] Precise intervention in stress fields: based on stress gradient model Lock the high-energy area and open the four grouting holes closest to the hot spot;

[0084] Smart material injection: 860 mL of nanocomposite gel was targeted and injected at a flow rate of 18 mL / s. The gel underwent a swelling-crosslinking reaction at a surrounding rock temperature of 48°C, expanding fourfold in volume within 60 seconds and generating a sustained radial expansion pressure of 8 MPa.

[0085] Energy and space-time rebalancing: Expansion pressure drives the broken rock mass to engage and reorganize deep inside, and the stress concentration area moves 5.1m outside the tunnel. At the same time, the 12Hz alternating magnetic field drives the Fe3O4 particles to move in a directional manner in the magnetic particle cavity, and the hysteresis loss power reaches 158W / m 3 .

[0086] S4, long-term coordination mechanism between support and surrounding rock, starting intelligent maintenance protocol after impact treatment:

[0087] Daily: 0.35T pulsed magnetic field stimulates micro-vibration of magnetic particles, with crack regeneration rate ≤ 0.008mm / d;

[0088] Weekly: Inject a self-repairing emulsion containing microcapsules. Toluene diisocyanate is released at the microcracks at the support interface, restoring 94% of the bond strength within 96 hours.

[0089] Monthly: Dynamically optimize the energy threshold based on the LSTM neural network to stabilize the energy accumulation rate below the safety threshold.

[0090] S5. Full-cycle performance verification and self-optimization: After the system was in operation for 24 months and experienced 9 impact events >180kJ, the test results showed that the cumulative roof movement was 62mm (traditional support >420mm); the average anchor prestress was 265kN, and the anchor prestress loss rate was 5.4%; the surrounding rock energy residual rate was stable in the range of 8.7%-11.3%; the energy release equivalent of microseismic events decreased by 52%, achieving the core goal of "zero impact damage and stress self-balance".

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A stress-energy dual-compensation tough anchor cable, characterized by: It includes a steel strand, the front end of which is fixed with a guide head and an intelligent anchoring head, the steel strand is provided with a bearing plate connected to the intelligent anchoring head, and a graded energy absorption unit, an energy compensation chamber and a self-locking anchor tail module are sequentially arranged along the axial direction of the steel strand; the graded energy absorption unit includes a buckling-inducing energy absorption layer, a variable friction damping module and a hydraulic negative stiffness mechanism; and the buckling-inducing energy absorption layer, the variable friction damping module and the hydraulic negative stiffness mechanism are sequentially connected along the axial direction of the steel strand.

2. The stress-energy dual-compensation ductile anchor cable according to claim 1, characterized in that: The guide head is a conical structure, with its small diameter end fixedly connected to the end of the steel strand, and its large diameter end fits with the end face of the intelligent anchoring head. The bearing plate is a circular plate structure with a through hole in the center for the steel strand to pass through. One side of the bearing plate is in contact with the end face of the intelligent anchoring head, and the other side of the bearing plate is connected to the buckling-inducing energy dissipation layer.

3. The stress-energy dual-compensation ductile anchor cable according to claim 1, characterized in that: The energy compensation chamber includes a sleeve, which is divided into a gel storage chamber and a magnetic particle chamber by a partition. The outer side of the magnetic particle chamber is surrounded by an excitation coil 2. The gel storage chamber is connected to an intelligent distributor. The intelligent distributor is connected to a grouting pipe, and an intelligent nozzle is provided at the end of the grouting pipe.

4. The stress-energy dual-compensation ductile anchor cable according to claim 1, characterized in that: The buckling inducing energy dissipation layer is a Cr-Ni alloy bellows, one end of the Cr-Ni alloy bellows is connected to the bearing plate, and the other end is connected to the variable friction damping module.

5. The stress-energy dual-compensation ductile anchor cable according to claim 1, characterized in that: The variable friction damping module comprises a titanium alloy sleeve, and the inner wall of the titanium alloy sleeve is provided with a shape memory alloy friction plate.

6. The stress-energy dual-compensation ductile anchor cable according to claim 1, characterized in that: The hydraulic negative stiffness mechanism includes an excitation coil 1, a silicone oil-based magnetorheological fluid and a composite magnetic shielding sleeve. The composite magnetic shielding sleeve encapsulates the silicone oil-based magnetorheological fluid. The magnetic shielding baffle is provided at one end of the excitation coil 1 close to the intelligent anchoring head. The magnetic shielding baffle is an annular structure and is made of nickel-iron alloy material. Its inner diameter is gap-fitted with the steel wire rope, and its outer diameter is interference-fitted with the graded energy absorption unit.

7. The stress-energy dual-compensation ductile anchor cable according to claim 1, characterized in that: The self-locking anchor tail module includes an isolation ring connected to the tail of the steel strand, and a wire-hanging ring is sleeved on the surface of the steel strand.

8. A method for supporting a stress-energy dual-compensation ductile anchor cable according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Drill anchor holes in the target area and implant the anchor system to create an initial low-stress field through pre-tightening force. S2, sequentially dissipating the impact energy through graded energy absorption units, including sequentially activating three-level energy dissipation mechanisms: buckling-induced energy dissipation, temperature-sensitive friction adaptation, and magnetic field-controlled rheology; S3. Based on the real-time monitoring of the surrounding rock energy state, a compensation material with phase change expansion characteristics is injected into the energy accumulation area; S4. Maintaining the surrounding rock-support synergistic system through periodic physical field excitation and material self-repair; S5. Optimize control thresholds based on dynamic monitoring parameters to achieve long-term stability.

9. A stress-energy dual-compensation ductile anchor cable support method according to claim 8, characterized in that: In step S2, the three-level energy consumption mechanism includes the following three stages: S21, buckling-induced energy dissipation stage: When the impact stress wave reaches the first intensity threshold, the buckling-induced energy dissipation layer undergoes axial plastic deformation, prolonging the stress wave action time and absorbing the initial impact energy. S22, temperature-sensitive friction adaptive stage: The temperature rise caused by repeated expansion of the surrounding rock triggers the dynamic enhancement of the friction coefficient of the variable friction damping module, dissipating the medium-frequency energy and suppressing the expansion acceleration; S23. For high-frequency residual stress waves, the intelligent fluid of the hydraulic negative stiffness mechanism is switched in rheological state through magnetic field excitation, generating a negative stiffness effect to offset the residual energy.

10. A stress-energy dual-compensation ductile anchor cable support method according to claim 8, characterized in that: In step S3, the compensation control logic for injecting the compensation material is specifically as follows: S31. Energy hotspot diagnosis: Monitor the strain energy density of the surrounding rock through a distributed sensor network and locate the energy accumulation area when it exceeds a preset threshold; S32, smart material injection: Inject composite gel material into the target area, using the surrounding rock environment to trigger its phase change expansion to generate radial support pressure; S33. Energy-stress rebalance: The expansion pressure drives the redistribution of the surrounding rock stress field, while the alternating magnetic field excites the magnetic particles to convert mechanical energy into heat energy for continuous dissipation.

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