A stress suppression-based deep well roadway floor heave cooperative prevention and control method and device

Abstract

The application relates to the field of mining engineering, and particularly discloses a deep well roadway floor heave cooperative prevention and control method and device based on stress inhibition, which comprises a cooperative supporting body, an ultrahigh-pressure water jet system and a fiber sensor network; the cooperative supporting body is composed of an outer sleeve, an intermediate layer and a core channel; the ultrahigh-pressure water jet system is connected with the core channel, and the fiber sensor network is arranged outside the cooperative supporting body; the specific steps are as follows: S1, a mine engineering vehicle is used for positioning and drilling a hole, the drilling depth is determined, the hole inclination angle is monitored in real time, and rock powder is collected; S2, a solidifying agent is configured and injected into the hole, the cooperative supporting body is implanted, and a pre-tightening force is applied; S3, the ultrahigh-pressure water jet system is started, the slotting depth is calculated based on jet parameters, and a pressure relief groove is formed through rotary cutting; and S4, the floor heave deformation is monitored through the sensor network, and the adaptive adjustment of the cooperative supporting body is set. The application solves the problems of traditional passive supporting lag, controllable difference of blasting pressure relief and the like, and improves the deep well roadway floor heave prevention and control efficiency and stability.

Description

Technical Field

[0001] This invention relates to the field of mining engineering technology, specifically to a method and device for the coordinated prevention and control of floor heave in deep well roadways based on stress suppression. Background Technology

[0002] As coal mining depths increase and scale expands, geological conditions become increasingly complex, leading to higher requirements for preventing floor heave in roadways. With continuous increases in mining depth, most coal mines in China have entered the stage of mining at depths of over 1,000 meters. The surrounding rock in deep roadways exhibits significant soft rock rheological characteristics and strong tectonic stress features. According to field observation data, floor heave in deep soft rock roadways can account for more than 70% of the total roadway deformation, severely restricting safe and efficient mine production. However, current traditional prevention methods have many problems:

[0003] (1) Passive support: It only strengthens the local load-bearing capacity, cannot eliminate the plastic flow caused by high ground stress, and has a long construction period. The response to deformation is delayed, and it may be difficult to restore the strength after support, resulting in high maintenance costs in the later stage.

[0004] (2) Blasting pressure relief method: It has poor controllability and is prone to uneven pressure relief, which may lead to excessive local pressure relief and rock mass fracture. The shock wave and vibration generated by blasting may damage the original rock structure, induce new cracks or aggravate the instability of the surrounding rock, and cause secondary disturbances. For areas with nearby coal seams, aquifers or important protective facilities, blasting vibration may cause risks such as water inrush and spontaneous combustion of coal seams, which limits its application scenarios.

[0005] (3) Conventional hydraulic cutting: low pressure, limited pressure relief range, unable to adapt to the dynamic evolution of mining stress. The coverage of a single cutting operation is limited, requiring multiple equipment moves in a large area, resulting in a long construction period and affecting the overall project progress.

[0006] (4) Defects in coordination: Existing technologies are mostly used independently, and there is no mechanical coupling between the support and depressurization systems, resulting in waste of resources.

[0007] Therefore, there is an urgent need for a stress-suppression-based method and device for the coordinated prevention and control of floor heave in deep well roadways, which can achieve real-time stress monitoring, ultra-high pressure directional decompression, and adaptive support, in order to improve the timeliness, controllability, and stability of floor heave prevention and control in deep roadways. Summary of the Invention

[0008] To address the aforementioned problems in the prior art, this invention provides a method and device for the coordinated prevention and control of floor heave in deep shaft roadways based on stress suppression, effectively solving problems such as the lag in traditional passive support and poor controllability of blasting pressure relief, thereby improving the efficiency and stability of floor heave prevention and control in deep shaft roadways.

[0009] To achieve the above objectives, this invention proposes a method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression, comprising:

[0010] S1. Drilling construction: The drilling is carried out by positioning the drilling with a mining engineering vehicle, the drilling depth is determined according to the thickness of the plastic zone of the surrounding rock, the drilling inclination is monitored in real time and rock powder is collected for lithology analysis;

[0011] S2. Device installation: Prepare curing agent and inject it into the drill hole, insert the coordinating support body and apply pre-tightening force;

[0012] S3. Ultra-high pressure relief construction: Start the ultra-high pressure water jet system, calculate the cutting depth based on the jet parameters, and perform rotary cutting to form a pressure relief groove;

[0013] S4. Intelligent control: The deformation of the bottom drum is monitored through a sensor network. When the deformation exceeds the threshold, the adaptive adjustment of the collaborative support body is triggered to realize the linkage between pressure relief and support.

[0014] Preferably, in S1, the drilling depth is 1.0-1.2 times the thickness of the plastic zone, the inclination angle is controlled at 90°±0.5°, and rock powder is collected and analyzed every 0.5m to analyze lithological changes.

[0015] Preferably, in S2, the curing agent preparation includes: mixing epoxy resin E-44 and 200-mesh quartz powder in proportion, stirring at 300 r / min for 2 minutes, adding curing agent T31 and stirring at 600 r / min for 1 minute, then adding steel fiber and stirring at 150 r / min for 30 seconds; injecting 60% of the anchoring agent into the device, applying a pre-tightening force of 80 kN, and then injecting the remaining anchoring agent.

[0016] Preferably, in S3, the jet parameters include the jet velocity, and the jet velocity formula is:

[0017] ;

[0018] In the formula, η is the nozzle efficiency coefficient, P is the working pressure, and ρ is the density of water;

[0019] The formula for calculating the kerf depth is:

[0020] ;

[0021] In the formula, d is the nozzle diameter. P is an empirical coefficient. eq The equivalent jet pressure is given by t, and t is a material characteristic parameter.

[0022] Preferably, in S3, the rotary cutting parameters are a rotation speed of 5 rpm and a pitch of 40 mm. An endoscope is used to check the retraction of the drill every 30 seconds. After drilling is completed, the hole is flushed for 30 seconds before proceeding to the next hole.

[0023] Preferably, in S4, intelligent control specifically includes: when the base drum displacement... When the deformation rate is not less than 0.1 mm / s or the pressure is less than 0.1 mm / s, the hydraulic bladder is pressurized and the shape memory alloy phase transformation is triggered. The support force is adjusted based on the PID control law, and the feedforward compensation term is: .

[0024] Preferably, it includes a collaborative support structure, an ultra-high pressure water jet system, and a fiber optic sensor network; the collaborative support structure consists of an outer sleeve, an intermediate layer, and a core channel, with the outer sleeve fitted outside the intermediate layer and the core channel located inside the intermediate layer; the ultra-high pressure water jet system is connected to the core channel, and the fiber optic sensor network is deployed on the outside of the collaborative support structure.

[0025] Preferably, the outer sleeve is made of NiTiNb shape memory alloy, the middle layer is an aramid composite hydraulic bladder, and the core channel is made of 316L stainless steel, used for the flow of ultra-high pressure water and the installation of sensor circuits.

[0026] Preferably, the ultra-high pressure water jet system includes a pulse generator, a rotating mechanism, and a nozzle. The pulse generator adopts a Helmholtz resonant cavity, the rotating mechanism achieves ±30° rotation angle adjustment through worm gear transmission, and the nozzle is made of YG8 hard alloy material.

[0027] Preferably, the fiber optic sensor network is used for real-time stress monitoring. The principal stress direction is calculated and transmitted to the control system to trigger ultra-high pressure water jet depressurization or coordinated support adjustment; the formula for calculating the principal stress direction is:

[0028] ;

[0029] In the formula, For shear stress, The stress is horizontal in the x-axis direction. The stress is horizontal along the y-axis.

[0030] Therefore, this invention proposes a method and device for the coordinated prevention and control of floor heave in deep well roadways based on stress suppression, the beneficial effects of which are as follows:

[0031] (1) Realize the coordinated linkage of "monitoring-pressure relief-support" to solve the defects of traditional technology in coordination. The surrounding rock stress and bottom heave deformation are monitored in real time through fiber optic sensor network. The ultra-high pressure water jet system is used to directionally cut and relieve pressure based on monitoring data. The support force is synchronously and adaptively adjusted by the support body. The three form a mechanical coupling, avoiding the waste of resources caused by independent application of support and pressure relief, and adapting to the dynamic evolution of mining stress.

[0032] (2) Improve the timeliness and controllability of prevention and control, and overcome the shortcomings of traditional methods. Compared with the lag in deformation response of passive support, the poor controllability of blasting pressure relief and the low pressure limitation of conventional hydraulic cutting, this invention can quickly eliminate high ground stress plastic flow and reduce the risk of rock mass breakage and secondary disturbance by using a threshold triggering mechanism of 48mm displacement or 0.1mm / s deformation rate combined with the precise cutting of ultra-high pressure water jet.

[0033] (3) Adaptable to complex deep well environments, reducing maintenance costs. The support structure uses weather-resistant materials that can withstand the rheology of deep soft rock and strong tectonic stress. The curing agent and pre-tightening force design enhance the anchoring stability of the device, reduce the problem of later support strength failure, and reduce the long-term maintenance cost of the mine.

[0034] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0035] Figure 1 This is a cross-sectional view of the device structure of the method and apparatus for coordinated prevention and control of floor heave in deep well roadways based on stress suppression, according to the present invention.

[0036] Figure 2 This is a roadway construction layout diagram of a method and device for the coordinated prevention and control of floor heave in deep well roadways based on stress suppression, according to the present invention.

[0037] Figure 3 This is a flowchart of the entire process of a method and device for the coordinated prevention and control of floor heave in deep well roadways based on stress suppression, according to the present invention.

[0038] Figure 4 This is an intelligent control system architecture diagram of a method and device for coordinated prevention and control of floor heave in deep well roadways based on stress suppression, according to the present invention.

[0039] Figure 5 This is an energy flow analysis diagram of a method and device for coordinated prevention and control of floor heave in deep well roadways based on stress suppression, according to the present invention.

[0040] Figure Labels

[0041] 1. Pressure relief groove; 2. Fiber optic sensing layer; 3. Shape memory alloy sleeve; 4. Hydraulic expansion bladder; 5. Ultra-high pressure water jet mechanism; 6. Roadway; 7. Mining engineering vehicle; 8. Pressure relief support device. Detailed Implementation

[0042] To make the technical solutions, advantages, and objectives of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the protection scope of this application.

[0043] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0044] like Figures 1-5 As shown, this invention provides a method and device for coordinated prevention and control of floor heave in deep well tunnels based on stress suppression. The device includes: a pressure relief groove 1, an optical fiber sensing layer 2, a shape memory alloy sleeve 3, a hydraulic expansion bladder 4, and an ultra-high pressure water jet mechanism 5. Among them, the shape memory alloy sleeve 3 is the outer sleeve, the hydraulic expansion bladder 4 is the middle layer, the core channel has the pipeline of the ultra-high pressure water jet mechanism 5 and the wiring of the optical fiber sensing layer 2, the optical fiber sensing layer 2 is arranged on the outside of the shape memory alloy sleeve 3, the pressure relief groove 1 is formed by cutting the ultra-high pressure water jet mechanism 5, and the whole constitutes an integrated structure of "monitoring-pressure relief-support".

[0045] The specific steps for coordinated prevention and control of floor heave in deep well tunnels include:

[0046] S1. Drilling Construction: The drilling is carried out by positioning the drilling with a mining engineering vehicle. The drilling depth is determined according to the thickness of the plastic zone of the surrounding rock. The drilling depth is 1.0-1.2 times the thickness of the plastic zone. The drilling inclination angle is monitored in real time by an electronic inclinometer and controlled at 90°±0.5°. Rock powder is collected every 0.5m to analyze the lithological changes.

[0047] S2. Equipment installation: The curing agent is prepared according to the specific process. The curing agent is epoxy resin E-44 mixed with 200 mesh quartz powder → curing agent T31 is added → steel fiber is added. The stirring speed and time are controlled in stages. First, 60% of the anchoring agent is injected into the borehole. After the coordinating support body is implanted, an 80kN pre-tightening force is applied. Finally, the remaining anchoring agent is injected.

[0048] S3. Ultra-high pressure relief construction: Start the ultra-high pressure water jet system, based on the jet velocity formula:

[0049] ;

[0050] In the formula, η is the nozzle efficiency coefficient, P is the working pressure, and ρ is the density of water;

[0051] Calculate the jet parameters, then use the slit depth formula:

[0052] ;

[0053] In the formula, d is the nozzle diameter. This is an empirical coefficient; Equivalent jet pressure; These are material-related characteristic parameters;

[0054] Determine the kerf depth, perform rotary cutting at a speed of 5 rpm and a pitch of 40 mm, and use an endoscope to retract the drill every 30 seconds to check. After drilling, flush for 30 seconds before working on the next hole.

[0055] S4. Intelligent Control: Real-time monitoring of surrounding rock stress via fiber optic sensor network. The principal stress directions are calculated using the formula for the principal stress directions:

[0056] ;

[0057] In the formula, For shear stress, The stress is horizontal in the x-axis direction. The stress is horizontal along the y-axis.

[0058] When the maximum principal stress reaches a critical value, it triggers a directional slit-cutting pressure relief using ultra-high pressure water jets, which employ pulsed ultra-high pressure water jets to form a deep pressure relief groove.

[0059] ;

[0060] In the formula, For the deep parameters of the pressure relief tank, The rock mass shearability coefficient. Nozzle diameter, For the tensile strength of rock, It is the attenuation factor;

[0061] To avoid stress superposition, the optimal spacing of the pressure relief grooves is calculated:

[0062] ;

[0063] In the formula, For elastic modulus, The thickness of the base strata. Poisson's ratio, Bending strength;

[0064] When low drum displacement is detected When the deformation rate is not less than 0.1 mm / s or the hydraulic bladder of the supporting structure is pressurized and the shape memory alloy undergoes phase transformation, the supporting force is adjusted based on the PID control law:

[0065] ;

[0066] In the formula, This is the proportionality coefficient; To control errors; This is due to the cumulative effect of errors; These are the differential coefficients; The rate of change of error; This is a feedforward compensation term;

[0067] The feedforward compensation term is calculated as follows:

[0068] ;

[0069] In the formula, The correlation coefficient is the second derivative. It is the second derivative of the displacement; The coefficient of change; The rate of change;

[0070] Simultaneously verify the control effect in real time; if the effect difference is... If the difference exceeds 5mm, adjust the PID parameters. The formula for the difference in control effect is:

[0071] ;

[0072] In the formula, a, b, and c are the coefficients of the control model; This is the displacement integral term; For displacement rate;

[0073] The parameter self-tuning rules are as follows:

[0074] ;

[0075] In the formula, This is the system's maximum output force; This is the displacement-related limit quantity.

[0076] Example 1

[0077] The method and device for coordinated prevention and control of bottom heave in deep well roadways based on stress suppression provided by this invention were applied to an 850m deep sandy mudstone track roadway. The system consists of a preliminary geological exploration module, an intelligent drilling module, a device installation module, an ultra-high pressure relief execution module, and an intelligent control module.

[0078] (1) Preliminary geological exploration module, determining basic parameters

[0079] Before construction, core sampling and geostress scanning are conducted to obtain the geomechanical parameters of the target tunnel and measure its uniaxial compressive strength. elastic modulus Poisson's ratio Plastic zone thickness .

[0080] (2) Intelligent drilling module for intelligent drilling positioning and construction.

[0081] A mining engineering vehicle is used as the positioning carrier, with the distance between the engineering vehicle and the roadway side ≥1.2m and the outrigger leveling error ≤0.5°. The laser positioning system is used to align with the designed hole position. Based on the thickness of the plastic zone, the drilling depth is determined to be 3.2m. The automatic drilling equipment is started, and the electronic inclinometer provides real-time feedback on the drilling inclination angle (controlled within 90°±0.5°). The operation is paused every 0.5m to collect rock powder and analyze the lithological changes using an X-ray fluorescence spectrometer to confirm that there is no abrupt change in the surrounding rock (such as from sandy mudstone to broken coal seam). If there is abrupt change in lithology, the drilling depth and angle are readjusted.

[0082] (3) Install the device module and prepare the curing agent and install the device.

[0083] The curing agent should be prepared according to the following process, with a single preparation amount suitable for one drilling requirement:

[0084] Step 1: Mix epoxy resin E-44 with 200 mesh quartz powder, place it in a high-speed mixing tank and stir at 300 r / min for 2 minutes to ensure that the quartz powder is evenly dispersed;

[0085] Step 2: Add curing agent T31, increase the speed to 600r / min and stir for 1 minute to form a uniform gel matrix;

[0086] Step 3: Add 5mm long steel fibers, reduce the speed to 150r / min and stir for 30 seconds to prevent the steel fibers from agglomerating.

[0087] The prepared curing agent is injected into the bottom of the borehole through the injection tube. After injecting 60% of the total anchoring agent, the injection tube is slowly pulled out. The coordinating support body, which has an outer NiTiNb shape memory alloy sleeve, an aramid composite hydraulic bladder in the middle, and a 316L stainless steel channel in the core, is then inserted into the borehole to the designed depth. An 80kN pre-tightening force is applied using a hydraulic wrench, and finally the remaining 40% of the anchoring agent is injected.

[0088] (4) Ultra-high pressure relief execution module

[0089] After the device is installed, start the ultra-high pressure water jet system. First, determine the jet parameters according to the jet velocity formula:

[0090] ;

[0091] In the formula, This refers to the nozzle efficiency coefficient. Due to work pressure; The density of water;

[0092] Calculations show that the jet velocity... = ;

[0093] Then, according to the rockburst formula:

[0094] ;

[0095] In the formula, The density of water; This is the equivalent quantity of the rate of change of flow velocity; For flow rate;

[0096] The measured rockburst

[0097] Then, the theoretical kerf depth is calculated based on the kerf depth formula:

[0098] ;

[0099] In the formula, Nozzle diameter; This is an empirical coefficient; Equivalent jet pressure; These are material-related characteristic parameters;

[0100] Determine the cut depth .

[0101] After obtaining the jet parameters, the laser rangefinder is initially positioned with the nozzle 50mm from the bottom of the hole. Then, a rotary cut is performed at a speed of 5rpm and a pitch of 40mm. Every 30 seconds, an endoscope is used to check the retraction of the drill. After drilling is completed, the hole is flushed for 30 seconds before proceeding to the next hole.

[0102] (5) Intelligent control module

[0103] The fiber optic sensor network deployed on the outside of the collaborative support structure collects the surrounding rock stress and bottom displacement, and transmits the data to the ground control system.

[0104] After the device entered its life cycle, monitoring showed that the deformation rate of the bottom drum was 0.08 mm / s and the displacement was 50.3 mm, exceeding [the specified value]. mm, triggering the control signal, the hydraulic bladder starts pressurizing, pressurizing to 12.7MPa, the deformation rate drops to 0.04mm / s, then the system stabilizes, the displacement of the bottom drum drops to 32.1mm, fluctuation 0.2mm.

[0105] The control effect is then calculated based on the formula for the difference in control effects:

[0106] ;

[0107] In the formula, a, b, and c are the coefficients of the control model; This is the displacement integral term; This represents the displacement rate.

[0108] Calculations show that For diameters of 1.2mm or less than 5mm, no adjustment of PID parameters is required.

[0109] Therefore, this invention provides a method and device for the coordinated prevention and control of floor heave in deep well roadways based on stress suppression. The device includes a coordinated support body, an ultra-high pressure water jet system, and a fiber optic sensor network. The method includes drilling, device installation, ultra-high pressure decompression, and intelligent control, which solves the shortcomings of traditional prevention and control methods and improves the efficiency and stability of prevention and control.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression, characterized in that, include: S1. Drilling construction: The drilling is carried out by positioning the drilling with a mining engineering vehicle, the drilling depth is determined according to the thickness of the plastic zone of the surrounding rock, the drilling inclination is monitored in real time and rock powder is collected for lithology analysis; S2. Device installation: Prepare curing agent and inject it into the drill hole, insert the coordinating support body and apply pre-tightening force; S3. Ultra-high pressure relief construction: Start the ultra-high pressure water jet system, calculate the cutting depth based on the jet parameters, and perform rotary cutting to form a pressure relief groove; S4. Intelligent control: The deformation of the bottom drum is monitored through a sensor network. When the deformation exceeds the threshold, the adaptive adjustment of the collaborative support body is triggered to realize the linkage between pressure relief and support. In S3, the jet parameters include the jet velocity, and the formula for the jet velocity is: ； In the formula, η is the nozzle efficiency coefficient, P is the working pressure, and ρ is the density of water; The formula for calculating the kerf depth is: ； In the formula, d is the nozzle diameter. P is an empirical coefficient. eq The equivalent jet pressure is given by t, where t is a material characteristic parameter. In S4, intelligent control specifically includes: when the bottom drum displacement... When the deformation rate is not less than 0.1 mm / s or the pressure is less than 0.1 mm / s, the hydraulic bladder is pressurized and the shape memory alloy phase transformation is triggered. The support force is adjusted based on the PID control law, and the feedforward compensation term is: ； In the formula, The correlation coefficient is the second derivative. It is the second derivative of the displacement; Bending strength; The coefficient of change; The rate of change; The stress-suppression-based deep well roadway floor heave collaborative prevention and control device includes a collaborative support body, an ultra-high pressure water jet system, and a fiber optic sensor network. The collaborative support body consists of an outer casing, an intermediate layer, and a core channel. The outer casing is fitted outside the intermediate layer, and the core channel is located inside the intermediate layer. The ultra-high pressure water jet system is connected to the core channel, and the fiber optic sensor network is deployed outside the collaborative support body. The outer sleeve is made of NiTiNb shape memory alloy, the middle layer is an aramid composite hydraulic bladder, and the core channel is made of 316L stainless steel, used for the flow of ultra-high pressure water and the installation of sensor circuits.

2. The method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression according to claim 1, characterized in that, In S1, the drilling depth is 1.0-1.2 times the thickness of the plastic zone, the dip angle is controlled at 90°±0.5°, and rock powder is collected and analyzed every 0.5m to analyze lithological changes.

3. The method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression according to claim 1, characterized in that, In S2, the curing agent preparation includes: mixing epoxy resin E-44 and 200-mesh quartz powder in proportion, stirring at 300 r / min for 2 minutes, adding curing agent T31 and stirring at 600 r / min for 1 minute, then adding steel fiber and stirring at 150 r / min for 30 seconds; injecting 60% of the curing agent into the device, applying a pre-tightening force of 80 kN, and then injecting the remaining curing agent.

4. The method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression according to claim 1, characterized in that, In S3, the rotary cutting parameters are 5 rpm and 40 mm pitch. An endoscope is used to check the retraction of the drill every 30 seconds. After drilling, the hole is flushed for 30 seconds before the next hole is drilled.

5. The method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression according to claim 1, characterized in that, The ultra-high pressure water jet system includes a pulse generator, a rotating mechanism, and a nozzle. The pulse generator adopts a Helmholtz resonant cavity, the rotating mechanism achieves ±30° rotation angle adjustment through worm gear transmission, and the nozzle is made of YG8 hard alloy material.

6. The method for coordinated prevention and control of floor heave in deep well roadways based on stress suppression according to claim 1, characterized in that, The fiber optic sensor network is used for real-time stress monitoring. The principal stress direction is calculated and transmitted to the control system to trigger ultra-high pressure water jet depressurization or coordinated support adjustment; the formula for calculating the principal stress direction is: ； In the formula, For shear stress, The stress is horizontal in the x-axis direction. The stress is horizontal along the y-axis.

Images