WO2022116229A1 - 一种基于真三轴应力下的微波智能加载致裂硬岩试验系统 - Google Patents

一种基于真三轴应力下的微波智能加载致裂硬岩试验系统 Download PDF

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Publication number
WO2022116229A1
WO2022116229A1 PCT/CN2020/134553 CN2020134553W WO2022116229A1 WO 2022116229 A1 WO2022116229 A1 WO 2022116229A1 CN 2020134553 W CN2020134553 W CN 2020134553W WO 2022116229 A1 WO2022116229 A1 WO 2022116229A1
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Prior art keywords
microwave
rock
temperature
acoustic
acoustic emission
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PCT/CN2020/134553
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English (en)
French (fr)
Inventor
冯夏庭
张九雨
林峰
李世平
苏香馨
童天扬
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东北大学
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Priority to CA3142646A priority Critical patent/CA3142646C/en
Priority to US17/618,378 priority patent/US11965860B2/en
Publication of WO2022116229A1 publication Critical patent/WO2022116229A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/60—Investigating resistance of materials, e.g. refractory materials, to rapid heat changes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02—Details
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02—Details
    • G01N3/06—Special adaptations of indicating or recording means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02—Details
    • G01N3/06—Special adaptations of indicating or recording means
    • G01N3/068—Special adaptations of indicating or recording means with optical indicating or recording means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G01N3/10—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
    • G01N3/12—Pressure testing
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014—Type of force applied
    • G01N2203/0016—Tensile or compressive
    • G01N2203/0019—Compressive
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/003—Generation of the force
    • G01N2203/0042—Pneumatic or hydraulic means
    • G01N2203/0048—Hydraulic means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/003—Generation of the force
    • G01N2203/0057—Generation of the force using stresses due to heating, e.g. conductive heating, radiative heating
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058—Kind of property studied
    • G01N2203/006—Crack, flaws, fracture or rupture
    • G01N2203/0067—Fracture or rupture
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/06—Indicating or recording means; Sensing means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/06—Indicating or recording means; Sensing means
    • G01N2203/0641—Indicating or recording means; Sensing means using optical, X-ray, ultraviolet, infrared or similar detectors
    • G01N2203/0647—Image analysis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/06—Indicating or recording means; Sensing means
    • G01N2203/0658—Indicating or recording means; Sensing means using acoustic or ultrasonic detectors

Definitions

  • the invention relates to the technical field of rock mechanics experimental devices, in particular to a microwave intelligent loading cracking hard rock test system based on true triaxial stress.
  • Microwave pretreatment of hard rock mass can reduce the mechanical properties of rock mass such as uniaxial strength, tensile strength, fracture toughness, etc., and then use mechanical method to fracture rock, which can improve rock breaking efficiency and reduce rock breaking cost.
  • the previous studies were all carried out in a stress-free state, while the engineering rock mass was mostly in a state of three-dimensional unequal stress, and complex stress adjustments would be experienced during the excavation process, and the three-dimensional stress would significantly affect the strength and deformation characteristics of the rock mass. Therefore, it is necessary to study the characteristics and mechanism of microwave-fractured rock mass under true triaxial stress.
  • the present invention provides a microwave intelligent loading cracking hard rock test system based on true triaxial stress, which can realize the microwave cracking hard rock test under true triaxial stress, It can realize microwave protection in the process of microwave radiation, and realize intelligent regulation of microwave power and microwave heating time.
  • a microwave intelligent loading cracking hard rock test system based on true triaxial stress including a true triaxial hard rock microwave cracking device, a rock response dynamic monitoring and microwave parameter intelligent control system, a controller and a computer.
  • Axial hard rock microwave fracturing device includes true triaxial stress loading device and hard rock microwave fracturing device;
  • the true triaxial stress loading device includes a loading frame and a rock sample moving structure arranged on the loading frame.
  • the loading frame includes an upper horizontal frame, a lower horizontal frame, a left vertical frame, a right vertical frame, and a rock sample arranged above the lower horizontal frame.
  • a transverse frame the transverse frame includes a front loading plate and a rear loading plate connected by four tie rods, a sample loading table is arranged on the side of the lower horizontal frame; a Y-direction load jack is installed below the upper horizontal frame, for Bearing the reaction force in the Y direction; X-direction load jacks are installed on the side of the left vertical frame close to the rock sample to carry the reaction force in the X direction; the rear loading plate is equipped with Z-direction load jacks for bearing the Z direction
  • the reaction force of the lower horizontal frame; the space between the top of the lower horizontal frame, the X-direction load jack, the Y-direction load jack and the Z-direction load jack constitutes a triaxial pressure chamber for placing rock samples;
  • the hard rock microwave fracturing device includes an excitation cavity, a rectangular waveguide, a magnetron, a thermocouple, a circulator, a cold water circulation, a flow meter, a power meter, an automatic impedance tuner, a coupler, a microwave heater and a shielding cavity, so the One end of the rectangular waveguide is connected to the excitation cavity, the other end of the rectangular waveguide is connected to the microwave heater, and a circulator, a coupler and an impedance automatic tuner are arranged on the rectangular waveguide in sequence;
  • the magnetron is installed in the excitation cavity Inside, and connected with the microwave power supply, the magnetron is also connected with the cold water circulation and the flow meter in turn, and the flow meter is used to monitor and display the flow of the cold water;
  • the circulator is connected with the water load and the thermocouple in turn, and the thermocouple is used for It is used to monitor and display the temperature of the water load;
  • the couplers are respectively connected with the
  • the rock response dynamic monitoring and microwave parameter intelligent control system includes a CCD industrial camera, a temperature acquisition device, and an electromagnetic and high temperature resistant acoustic wave-acoustic emission integrated sensor; the CCD industrial camera records the images during the microwave cracking process in real time and transmits them to the system.
  • the computer saves and displays; the temperature acquisition device collects the real-time temperature of the rock and transmits it to the computer for storage and display; the anti-electromagnetic and high-temperature resistant acoustic wave-acoustic emission integrated sensor is connected with the acoustic emission instrument, and the anti-electromagnetic high temperature resistant acoustic wave-acoustic emission The integrated sensor of emission monitors the real-time wave speed and acoustic emission of the rock and transmits it to the computer for storage and display through the acoustic emission instrument; the embedded program of the computer calculates the wave speed drop, the cumulative number of acoustic emission and the acoustic emission rate according to the real-time wave speed and acoustic emission of the rock, and calculates the The real-time rock temperature, wave velocity drop, acoustic emission cumulative number and acoustic emissivity are sent to the controller, and the controller adjusts and adjusts the microwave power and microwave heating time according to the wave velocity drop, rock
  • the rock sample moving structure includes a mobile cantilever crane, a Z-direction push jack and an X-direction push jack, and the mobile cantilever crane is connected to the top of the upper horizontal frame for hoisting or hoisting the rock sample.
  • pressure sensors are installed on the side walls of the cylinders of the X-direction load jacks, the Y-direction load jacks and the Z-direction load jacks, respectively, and the three pressure sensors are respectively connected to the computer to transmit the pressure data to the computer for storage and display.
  • a rectangular hole is formed in the middle of the front loading plate, and the length and width of the rectangular hole are respectively larger than the length and width of the front surface of the rock sample, so that the microwave radiation surface of the rock sample does not contact the front loading plate at all.
  • the rectangular waveguide passes through the shielding cavity and is connected with the shielding cavity through aluminum foil tape and soft metal mesh.
  • the microwave heater adopts a microwave surface heater or a microwave in-hole heater.
  • the temperature acquisition device is an infrared thermal imager installed in front of the rock sample or a distributed high-temperature optical fiber installed on the rock sample hole wall; the infrared thermal imager collects the real-time temperature of the rock surface and transmits it to a computer for storage and display.
  • the distributed high-temperature optical fiber is connected with a demodulator, the distributed high-temperature optical fiber collects the real-time temperature of the rock hole wall, and the real-time temperature of the rock hole wall is demodulated by the demodulator and transmitted to the computer for storage and display.
  • the infrared thermal imager and the CCD industrial camera are respectively arranged in a shielding box, the shielding box is connected with a cut-off circular waveguide, and the cut-off circular waveguide extends into the shielding cavity.
  • the electromagnetic and high temperature resistant acoustic wave-acoustic emission integrated sensor includes a piezoelectric element, a metal shell packaged outside the piezoelectric element, and a PTFE heat insulation jacket wrapped outside the metal shell; The front end is connected with a quartz probe, the quartz probe is in direct contact with the surface of the rock sample, and the piezoelectric element is connected with the shielding wire.
  • the specific process of adjusting the microwave power and microwave heating time by the rock response dynamic monitoring and microwave parameter intelligent control system includes:
  • the computer presets the microwave initial power, the microwave initial heating time, the rock initial wave speed and the wave velocity drop threshold through the embedded program, and transmits the above parameters to the controller.
  • the temperature of the critical rupture point, the temperature of the starting point of the stable crack growth, the temperature of the starting point of the unstable crack growth, the heating time of the starting point of the unstable crack growth and the time of the unstable crack growth the controller controls the microwave power to start with the preset microwave. power and microwave initial heating time to fracture rock;
  • the integrated sensor of anti-electromagnetic and high-temperature resistant acoustic wave and acoustic emission monitors the real-time wave speed and acoustic emission of the rock, and sends the real-time wave speed and acoustic emission of the rock to the computer. transfer to a computer;
  • the computer subtracts the initial wave velocity of the rock from the real-time wave velocity of the rock through the embedded program to obtain the wave velocity drop, and accumulates the acquired acoustic emission counts to obtain the accumulated acoustic emission counts, and then calculates the acoustic emission counts collected within 1s to obtain the acoustic emission rate.
  • the real-time rock temperature, wave velocity drop, cumulative number of acoustic emissions and acoustic emissivity are transmitted to the controller.
  • the controller compares the wave velocity drop with the preset wave velocity drop threshold. If the wave velocity drop is greater than or equal to the wave velocity drop threshold, the controller controls the microwave power to stop.
  • the controller compares the real-time temperature of the rock, the cumulative number of acoustic emissions, and the acoustic emissivity with the built-in temperature of the critical fracture point of the rock, the temperature of the starting point of stable crack growth, and the temperature of the crack.
  • the temperature at the starting point of the instability expansion, the threshold of the cumulative number of acoustic emissions and the threshold of the acoustic emission rate are compared as follows:
  • the controller controls the microwave power source to maintain the initial microwave power and the initial microwave heating time to crack the rock;
  • the controller controls the microwave power supply to increase the microwave power to crack the rock; if the cumulative number of emission is higher than or equal to the threshold of the cumulative number of acoustic emissions, it means that the initial microwave power is sufficient, and the controller controls the microwave power supply to maintain the initial microwave power to continue to crack the rock. ;
  • the relationship between the acoustic emissivity and the acoustic emissivity threshold is judged. If the acoustic emissivity is less than the acoustic emissivity threshold, it means that the microwave If the initial power is insufficient, the controller controls the microwave power supply to increase the microwave power to crack the rock; if the acoustic emission rate is greater than or equal to the acoustic emission rate threshold, it indicates that the microwave initial power is sufficient, and the controller controls the microwave power supply to maintain the microwave initial power to continue to crack the rock;
  • the relationship between the acoustic emissivity and the acoustic emissivity threshold is judged. If the acoustic emissivity is less than the acoustic emissivity threshold, it means that the initial microwave power is insufficient, and the controller controls the microwave power to increase The microwave power is used to crack the rock; if the acoustic emissivity is greater than or equal to the acoustic emissivity threshold, the initial microwave power is sufficient, and the controller controls the microwave power supply to maintain the microwave initial power to continue to crack the rock; at the same time, determine the initial microwave heating time and crack instability propagation The relationship between the heating time at the starting point, if the initial microwave heating time is less than or equal to the heating time at the starting point of the crack instability propagation, the controller controls the microwave power supply to extend the microwave heating time; , calculate the difference between the initial microwave heating time and the heating time at the starting point of the crack instability
  • the present invention can realize the microwave cracking hard rock test under true triaxial stress, and can realize the loading mode of five-sided compression and single-sided void (front) through the true triaxial stress loading device, which is used to simulate the excavation face rock. the stress state of the body;
  • the present invention adopts cold water circulation, thermocouple, circulator, flow meter, power meter, automatic impedance tuner and shielding cavity for microwave protection during the microwave loading process, so as to ensure the safe and stable operation of the hard rock microwave cracking device;
  • the present invention realizes the temperature, hard rock fracture evolution, hard rock fracture degree monitoring during microwave heating process, and intelligent regulation of microwave power and microwave heating time through the dynamic monitoring of rock response and the intelligent control system of microwave parameters, which solves the problem of engineering application. It is easy to cause technical problems such as insufficient or excessive microwave fracturing of rock mass, resulting in low fracturing efficiency or energy waste;
  • the present invention can realize the monitoring of rock temperature, wave speed, acoustic emission and image in the process of microwave fracturing through the dynamic monitoring of rock response and the intelligent control system of microwave parameters, so as to realize the evaluation of the effect of microwave fracturing hard rock, and research on the fracture law and mechanism. provide data.
  • FIG. 1 is a perspective view 1 of a microwave intelligent loading cracking hard rock test system based on true triaxial stress provided by an embodiment of the present invention
  • FIG. 2 is a perspective view 2 of a microwave intelligent loading cracking hard rock test system based on true triaxial stress provided by an embodiment of the present invention
  • FIG. 3 is a side view of a microwave intelligent loading cracking hard rock test system based on true triaxial stress provided by an embodiment of the present invention
  • FIG. 4 is a cross-sectional view of a true triaxial stress loading device provided by an embodiment of the present invention.
  • FIG. 5 is a schematic structural diagram of a dynamic monitoring system for rock response under a strong microwave field provided by an embodiment of the present invention
  • FIG. 6 is a schematic structural diagram of an integrated sensor for electromagnetic resistance and high temperature resistance and acoustic wave-acoustic emission provided by an embodiment of the present invention
  • FIG. 7 is a schematic diagram of the adjustment of microwave power and microwave heating time by the system for dynamic monitoring of rock response and intelligent control of microwave parameters provided by an embodiment of the present invention.
  • 1-Mobile cantilever crane 2-Upper horizontal frame, 3-Y-direction load jack, 4-Y-direction displacement sensor, 5-Z-direction displacement sensor, 6-tie rod, 7-Z-direction load jack, 8-rear loading plate , 9-Z-direction pressure sensor, 10-sample stage, 11-lower horizontal frame, 12-rock sample, 13-shielding cavity, 14-microwave surface heater, 15-rectangular waveguide, 16-front loading plate, 17- Y-direction pressure sensor, 18-impedance auto-tuner, 19-power meter, 20-coupler, 21-circulator, 22-water load, 23-magnetron, 24-excitation cavity, 25-cold water circulation, 26- Flowmeter, 27-thermocouple, 28-lifting platform, 29-left vertical frame, 30-X direction load jack, 31-piston pressure head, 32-triaxial pressure chamber, 33-rigid pressure plate, 34-movable pressure block, 35- Right vertical frame, 36- X-direction push
  • the present invention provides a microwave intelligent loading cracking hard rock test system based on true triaxial stress, including true triaxial hard rock microwave cracking device, rock response dynamic monitoring and microwave parameter intelligent control system, controller (not shown in the figure) and computer 49, the true triaxial hard rock microwave fracturing device includes a true triaxial stress loading device and a hard rock microwave fracturing device;
  • the true triaxial stress loading device includes a loading frame and a rock sample moving structure arranged on the loading frame.
  • the loading frame includes an upper horizontal frame 2 , a lower horizontal frame 11 , a left vertical frame 29 , a right vertical frame 35 , and is arranged above the lower horizontal frame 11 .
  • the transverse frame 38 includes the front loading plate 16 and the rear loading plate 8 connected by four tie rods 6, the side of the lower horizontal frame 11 is provided with a sample loading table 10; 3.
  • the reaction force in the Y direction It is used to carry the reaction force in the Y direction; the side of the left vertical frame 29 close to the rock sample 12 is installed with an X direction load jack 30 to carry the reaction force in the X direction; the rear loading plate 8 is installed with a Z direction load jack 7, For bearing the reaction force in the Z direction; the top of the lower horizontal frame 11, the space between the X-direction load jack 30, the Y-direction load jack 3 and the Z-direction load jack 7 constitute a triaxial pressure chamber 32 for placing the rock sample 12 ;
  • the hard rock microwave fracturing device includes an excitation cavity 24, a rectangular waveguide 15, a magnetron 23, a thermocouple 27, a circulator 21, a cold water circulation 25, a flow meter 26, a power meter 19, an automatic impedance tuner, a coupler 20, a microwave
  • the heater and the shielding cavity 13 one end of the rectangular waveguide 15 is connected to the excitation cavity 24, the other end of the rectangular waveguide 15 is connected to the microwave heater, and the rectangular waveguide 15 is sequentially provided with a circulator 21, a coupler 20 and an automatic impedance tuner 18;
  • the magnetron 23 is installed inside the excitation cavity 24 and is connected to the microwave power supply.
  • the magnetron 23 is also connected to the cold water circulation 25 and the flow meter 26 in turn.
  • the flow meter 26 is used to monitor and display the flow of cold water;
  • the water load 22 is connected with a thermocouple 27, and the thermocouple 27 is used to monitor and display the temperature of the water load 22;
  • the coupler 20 is respectively connected with the power meter 19 and the impedance automatic tuner 18;
  • the shielding cavity 13 is arranged outside the rectangular waveguide 15, and fixedly connected with the front loading plate 16 for shielding the electromagnetic energy not absorbed by the rock sample 12;
  • the rock response dynamic monitoring and microwave parameter intelligent control system includes a CCD industrial camera 43 installed on the rock sample 12, a temperature acquisition device, and an electromagnetic and high temperature resistant acoustic wave-acoustic emission integrated sensor 46; the CCD industrial camera 43 records the microwave cracking process in real time.
  • the image is transmitted to the computer 49 for storage and display;
  • the temperature acquisition device collects the real-time temperature of the rock and transmits it to the computer 49 for storage and display;
  • the electromagnetic and high temperature resistant acoustic wave-acoustic emission integrated sensor 46 is connected with the acoustic emission instrument 47, which is resistant to electromagnetic and high temperature.
  • the acoustic wave-acoustic emission integrated sensor 46 monitors the real-time wave speed and acoustic emission of the rock and transmits it to the computer 49 through the acoustic emission device 47 for storage and display; the embedded program of the computer 49 calculates the wave speed drop and the cumulative number of acoustic emission according to the real-time wave speed and acoustic emission of the rock. Harmonize the acoustic emissivity, and send the rock real-time temperature, wave velocity drop, acoustic emission cumulative number and acoustic emissivity to the controller, and the controller adjusts and adjusts the microwave power and Microwave heating time.
  • the hard rock microwave fracturing device is placed on the lifting platform 28, so that the hard rock microwave fracturing device can move back and forth, left and right, and up and down.
  • the lifting platform 28 adopts the prior art.
  • the loading frame provides reaction force for the three-way stress, and the top and bottom of the left vertical frame 29 and the right vertical frame 35 are bolted to the upper horizontal frame 2 and the lower horizontal frame 11, respectively.
  • the X-direction load jack 30, the Y-direction load jack 3 and the Z-direction load jack 7 are respectively controlled by the servo control system, the servo control system adopts the prior art, the servo control system is connected with the computer 49, and the computer 49 realizes the three Independent loading and unloading of loads in each direction.
  • the rock sample 12 ensures its force balance through the frictional force it receives in the X and Y directions.
  • the friction coefficient of the rock sample 12 in the X and Y directions is less than 0.5
  • the rock sample 12 When the friction coefficients in the X and Y directions are greater than or equal to 0.5, the X-direction load jack 30, the Y-direction load jack 3 and the Z-direction load jack 7 are loaded at the same loading rate at the same time; and when the three-direction stress is unloaded, The Z-direction load should be unloaded first, and then the X- and Y-direction loads should be unloaded gradually.
  • the true triaxial stress loading device of the present invention can be applied to a cube rock sample 12 with a side length of 40 cm at most, and the test of different rock samples 12 can be
  • the microwave power supply provides power for the magnetron 23, the magnetron 23 converts electrical energy into electromagnetic energy, and the magnetron 23 in the excitation cavity 24 generates electromagnetic waves that are transmitted along the rectangular waveguide 15, and sequentially pass through the circulator 21 and the coupler. 20 and the impedance automatic tuner 18, and finally radiate to the rock sample 12 (surface or hole) through a microwave heater (microwave surface heater 14 or microwave in-hole heater 51).
  • the impedance automatic tuner 18 adopts the existing technology, which can automatically detect the load impedance of the rock sample 12 and adjust the impedance of the microwave fracturing device in time to match the load impedance of the rock sample 12 to the greatest extent, so as to reduce the microwave reflected power.
  • the shielding cavity 13 is a metal box closed around it, which is the intermediate connection between the true triaxial stress loading device and the hard rock microwave cracking device, and is fixedly connected with the front loading plate 16 to shield the electromagnetic energy not absorbed by the rock sample 12, The electromagnetic waves are confined within the shielding cavity 13 .
  • the moving structure of the rock sample 12 includes a mobile cantilever crane 1, a Z-direction push jack 37 and an X-direction push jack 36, the mobile cantilever crane 1 is connected to the top of the upper horizontal frame 2, and is used for lifting the rock sample 12 or lifting it from the loading.
  • Sample platform 10; Z-direction push jack 37 is arranged above the sample loading platform 10 for pushing rock sample 12 to or from the side of right vertical frame 35;
  • X-direction push jack 36 is arranged inside the right vertical frame 35, It is used to push the rock sample 12 on the side of the right vertical frame 35 to or from the triaxial pressure chamber 32 .
  • the mobile cantilever crane 1 adopts the prior art, and the side of the right vertical frame 35 close to the rock sample 12 is provided with a guide rail and a movable pressing block 34 that can move up and down along the guide rail, as shown in FIG. 4 for rock sample loading Route 41 and rock sample unloading route 42, when the rock sample 12 is loaded, move the movable block 34 up along the guide rail and fix it, the mobile cantilever crane 1 lifts the rock sample 12 to the loading table 10, and then pushes the rock sample 12 through the Z direction.
  • the jack 37 and the X-direction push jack 36 push the rock sample 12 into the triaxial pressure chamber 32, and then move the movable pressure block 34 down to the sample loading platform 10 along the guide rail, as the passive end of the X-direction stress, the movable pressure block 34 A rigid pressure plate 33 is placed between the rock sample 12.
  • the X-direction push jack 36 and the Z-direction push jack 37 are controlled by the remote control to work; when the rock sample 12 is unloaded, the movable pressure block 34 is moved up along the guide rail and moved upward.
  • the X-direction push jack 36 moves the rock sample 12 out in the X direction, and then the Z-direction push jack 37 is used to move the rock sample 12 out in the Z direction, and finally the rock sample 12 is lifted from the sample loading platform 10 by the mobile cantilever crane 1 .
  • Pressure sensors are installed on the side walls of the cylinders of the X-direction load jack 30, the Y-direction load jack 3 and the Z-direction load jack 7, respectively. Connect, transmit the pressure data to the computer 49 for storage and display, and the three pressure sensors are used to monitor the pressure of the oil cylinders of the X-direction load jack 30, the Y-direction load jack 3 and the Z-direction load jack 7, respectively.
  • the load jacks in each direction are loaded to the load of the rock sample 12; displacement sensors are installed on the piston indenters 31 of the X-direction load jack 30, Y-direction load jack 3 and Z-direction load jack 7, respectively, X-direction displacement sensor 39, Y-direction
  • the displacement sensor 4 and the Z-direction displacement sensor 5 are respectively connected to the computer 49 to transmit the displacement data to the computer 49.
  • the three displacement sensors are respectively used to monitor the X-direction load jack 30, the Y-direction load jack 3 and the Z-direction load jack 7.
  • the displacements of the rock samples 12 in each direction are obtained through the movement of the pistons of the respective load jacks; the computer 49 compares the real-time pressure data of the three jacks with their respective set pressures, and compares the real-time displacement data of the three jacks with the respective set pressures. Compare with their respective set displacements, and then control the X-direction load jack 30, Y-direction load jack 3 and Z-direction load jack 7 through the servo control system to achieve independent loading and unloading in three directions.
  • a rectangular hole is opened in the middle of the front loading plate 16, and the length and width of the rectangular hole are respectively larger than the length and width of the front surface of the rock sample 12, so that the microwave radiation surface of the rock sample 12 (ie, the front surface of the rock sample 12) is completely incompatible with the front loading plate. plate 16 contacts.
  • the rectangular waveguide 15 passes through the shielding cavity 13 and is connected with the shielding cavity 13 through aluminum foil tape and soft metal mesh to prevent electromagnetic waves from leaking from the connection between the two.
  • the gaps between the components and between the loading components are filled, sealed and fixed with aluminum foil tape, soft metal mesh and magnetic components, or aluminum foil tape, soft metal mesh and magnetic components to prevent electromagnetic waves from leaking from the above gaps. Realize the coupling of microwave radiation and true triaxial stress loading.
  • the microwave heater adopts the microwave surface heater 14 or the microwave in-hole heater 51.
  • the microwave heater is used to radiate microwave energy in a directional manner.
  • the microwave surface heater 14 can crack the rock on the surface to assist in mechanically breaking the hard rock.
  • the microwave in-hole heater 51 can Fractures hard rock within the borehole to reduce the risk of rockburst.
  • the temperature acquisition device is an infrared thermal imager 45 installed in front of the rock sample 12 or a distributed high-temperature optical fiber 50 installed on the wall of the rock sample 12; the infrared thermal imager 45 collects the real-time temperature of the rock surface and transmits it to a computer 49 for storage and display;
  • the distributed high temperature optical fiber 50 is connected to the demodulator 48 , the distributed high temperature optical fiber 50 collects the real-time temperature of the rock hole wall, and the real-time temperature of the rock hole wall is demodulated by the demodulator 48 and transmitted to the computer 49 for storage and display.
  • the infrared thermal imager 45 and the CCD industrial camera 43 are respectively disposed in the shielding box 44 , the shielding box 44 is connected with the cut-off circular waveguide, and the cut-off circular waveguide extends into the shielding cavity 13 .
  • the shielding box 44 is a closed metal box connected with a cut-off circular waveguide.
  • the cut-off circular waveguide connected to the shielding box 44 can not only be used for shielding electromagnetic waves, but also can be used as an observation hole for information monitoring.
  • Aluminum foil paper is used for connection; when the microwave surface is cracked, the infrared thermal imager 45 installed in the shielding box 44 can collect the real-time temperature of the rock surface; the CCD industrial camera 43 installed in the shielding box 44 can monitor the cracking process of the rock.
  • the computer 49 is respectively connected with the CCD industrial camera 43, the temperature acquisition device, the acoustic emission meter 47 and the controller, the controller is connected with the microwave power supply, and when the temperature acquisition device is the infrared thermal imager 45, the computer 49 is connected with the infrared The thermal imager 45 is connected; when the temperature acquisition device is the distributed high-temperature optical fiber 50 , the computer 49 is connected to the demodulator 48 .
  • the CCD industrial camera 43 is installed on the opposite side of the rock sample 12 to monitor the fracture process of the rock.
  • the CCD industrial camera 43 records the images during the microwave fracturing process in real time. The images during the cracking process can be used to obtain the deformation law of the rock.
  • the infrared thermal imager 45 is installed on the front or side of the rock sample 12 to monitor the rock surface temperature in real time;
  • the high-temperature optical fiber 50 and the demodulator 48 outside the shielding cavity 13 are used for temperature measurement.
  • One end of the distributed high-temperature optical fiber 50 is fixed on the wall of the rock sample 12, and the other end is connected to the demodulator 48.
  • the demodulator 48 is connected to the computer 49. It is completely unaffected by strong electromagnetic fields.
  • the distributed high-temperature optical fiber 50 uses high-temperature adhesive tape to fix the 12-hole rock sample at multiple points to ensure close contact with the 12-hole wall of the rock sample.
  • the electromagnetic and high temperature resistant acoustic wave-acoustic emission integrated sensor 46 includes a piezoelectric element 54, a metal casing 56 encapsulated outside the piezoelectric element 54, and a polytetrafluoroethylene heat shield 55 wrapped outside the metal casing 56;
  • the front end is connected to the quartz probe 53 , the quartz probe 53 is in direct contact with the surface of the rock sample 12 , and the piezoelectric element 54 is connected to the shielded wire 58 .
  • the piezoelectric element 54 is packaged with a metal shell 56 , and the outside of the metal shell is wrapped with a PTFE heat-insulating sleeve 55 , which can shield the interference of strong electromagnetic fields and high temperatures.
  • the front end of the metal shell 56 is connected to a quartz probe. 53 is in direct contact with the surface of the rock sample 12, and can withstand a maximum temperature of 400 °C.
  • the shielded wire 58 is used to connect with the acoustic emission meter 47.
  • the shielded wire 58 passes through the metal shell 56 and the outside of the PTFE heat shield 55.
  • a joint 57 is provided , the connector 57 is used to protect the shielded wire 58 .
  • the integrated sensor 46 for electromagnetic and high temperature resistance and acoustic wave-acoustic emission is installed on the surface of the rock sample 12 through the mounting pressure plate 52.
  • the installation pressure plate 52, the installation pressure plate 52 is provided with a lead groove and a through hole, and the lead groove is located on the side of the installation pressure plate 52 away from the rock sample 12, even if the lead groove is not close to the surface of the rock sample 12; Acoustic emission integrated sensor 46 .
  • at least one rigid pressing plate 33 (without being fixed) is also provided on the side of each mounting pressing plate 52 away from the rock sample 12 .
  • the specific process of adjusting the microwave power and microwave heating time by the rock response dynamic monitoring and microwave parameter intelligent control system includes:
  • the computer 49 presets the microwave initial power, the microwave initial heating time, the rock initial wave velocity and the wave velocity drop threshold through the embedded program, and transmits the above parameters to the controller, which has built-in acoustic emission cumulative number threshold, acoustic emission rate threshold, The temperature of the critical fracture point of the rock, the temperature of the starting point of the stable crack growth, the temperature of the starting point of the unstable crack growth, the heating time of the starting point of the unstable crack growth and the time of the unstable crack growth, the controller controls the microwave power supply to the preset microwave power.
  • the integrated sensor 46 of anti-electromagnetic and high temperature resistant acoustic wave and acoustic emission monitors the real-time wave speed and acoustic emission of the rock, and sends the real-time wave speed and acoustic emission of the rock to the computer 49.
  • the temperature acquisition device collects the real-time rock speed and acoustic emission. temperature and transfer to computer 49;
  • the computer 49 subtracts the initial wave velocity of the rock from the real-time wave velocity of the rock through the embedded program to obtain the wave velocity drop, accumulates the acquired acoustic emission counts to obtain the accumulated acoustic emission count, and then calculates the acoustic emission counts collected within 1 s to obtain the acoustic emission rate.
  • the controller sends the rock real-time temperature, wave velocity drop, cumulative number of acoustic emission and acoustic emission rate to the controller, the controller compares the wave velocity drop with the preset wave velocity drop threshold, if the wave velocity drop is greater than or equal to the wave velocity drop threshold, the controller controls the microwave The power supply stops heating to prevent excessive cracking; if the wave velocity drop is less than the wave velocity drop threshold, the controller compares the real-time temperature of the rock, the cumulative number of acoustic emissions, and the acoustic emission rate with the built-in temperature of the rock critical rupture point and the temperature of the starting point of stable crack growth. , the temperature at the starting point of crack instability growth, the threshold of the cumulative number of acoustic emission and the threshold of acoustic emission rate are compared as follows:
  • the controller controls the microwave power source to maintain the initial microwave power and the initial microwave heating time to crack the rock;
  • the controller controls the microwave power supply to increase the microwave power to crack the rock; if the cumulative number of emission is higher than or equal to the threshold of the cumulative number of acoustic emissions, it means that the initial microwave power is sufficient, and the controller controls the microwave power supply to maintain the initial microwave power to continue to crack the rock. ;
  • the relationship between the acoustic emissivity and the acoustic emissivity threshold is judged. If the acoustic emissivity is less than the acoustic emissivity threshold, it means that the microwave If the initial power is insufficient, the controller controls the microwave power supply to increase the microwave power to crack the rock; if the acoustic emission rate is greater than or equal to the acoustic emission rate threshold, it indicates that the microwave initial power is sufficient, and the controller controls the microwave power supply to maintain the microwave initial power to continue to crack the rock;
  • the relationship between the acoustic emissivity and the acoustic emissivity threshold is judged. If the acoustic emissivity is less than the acoustic emissivity threshold, it means that the initial microwave power is insufficient, and the controller controls the microwave power to increase The microwave power is used to crack the rock; if the acoustic emissivity is greater than or equal to the acoustic emissivity threshold, the initial microwave power is sufficient, and the controller controls the microwave power supply to maintain the microwave initial power to continue to crack the rock; at the same time, determine the initial microwave heating time and crack instability propagation The relationship between the heating time at the starting point, if the initial microwave heating time is less than or equal to the heating time at the starting point of the crack instability propagation, the controller controls the microwave power supply to extend the microwave heating time; , calculate the difference between the initial microwave heating time and the heating time at the starting point of the crack instability
  • the controller controls the microwave power supply to prolong the microwave heating time; if the difference between the initial microwave heating time and the heating time at the starting point of crack instability propagation is greater than the crack instability propagation time (0-60s), the controller controls the microwave power supply to shorten the microwave heating time.
  • the temperature of the starting point of stable crack growth in order to obtain the temperature of the rock critical rupture point, the temperature of the starting point of stable crack growth, the temperature of the starting point of unstable crack growth, the heating time of the starting point of unstable crack growth, the time of unstable crack growth, and the cumulative number of acoustic emission
  • a large number of microwave fracturing tests need to be carried out in advance to obtain the relationship between the real-time temperature of the rock and the cumulative number of acoustic emissions, the relationship between the real-time temperature of the rock and the acoustic emissivity, the real-time temperature of the rock and the microwave power and microwave heating.
  • the relationship diagram of time according to the above relationship diagram, the temperature of the critical fracture point of the rock, the temperature of the starting point of stable crack growth, the temperature of the starting point of unstable crack growth, the heating time of the starting point of unstable crack growth, the temperature of the starting point of unstable crack growth, the temperature of the starting point of unstable crack growth, the temperature of the starting point of unstable crack growth, the Time, Accumulation Threshold of Acoustic Emission and Acoustic Emissivity Threshold.
  • the rock response dynamic monitoring and microwave parameter intelligent control system can monitor the temperature in the microwave fracturing process and the rock fracture process in real time, and provide data for subsequent evaluation of the microwave fracturing rock effect.
  • the wave velocity decreases and the acoustic emission occurs.
  • the dynamic monitoring of the rock response and the intelligent control system of the microwave parameters actively control the microwave power and microwave heating time according to the dynamic feedback of the temperature and the acoustic emission.
  • the microwave power can be increased to realize microwave intelligent loading of cracked hard rock suitable for engineering field and laboratory tests, and to improve the efficiency of microwave cracked hard rock and the utilization rate of microwave energy.
  • the wave velocity drop is a feedback index of rock fracture degree, which is used to evaluate the effect of microwave cracking of rock.
  • Acoustic emission cumulative number The acoustic emissivity is a feedback index for the development of rock fractures.
  • the real-time temperature of the rock monitored by the infrared thermal imager 45 or the distributed high-temperature optical fiber 50 can be used to study the heating characteristics of the rock, and the conditions for rock fracture to be determined by the temperature. Therefore, the present invention The trend and stage of rock fracture are judged according to temperature and acoustic emission.

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Abstract

一种基于真三轴应力下的微波智能加载致裂硬岩试验系统，属于岩石力学实验装置技术领域。该系统包括：加载框架和岩样移动结构组成的真三轴应力加载装置；激励腔（24）、矩形波导（15）、磁控管（23）、热电偶（27）、环形器（21）、冷水循环（25）、流量计（26）、功率计（19）、阻抗自动调谐器（18）、耦合器（20）、微波表面加热器（14）和屏蔽腔（13）组成的硬岩微波致裂装置；以及CCD工业相机（43）、温度采集装置和防电磁耐高温声波-声发射一体化传感器（46）组成的岩石响应动态监测与微波参数智能调控系统。该系统实现了真三轴应力下的微波致裂硬岩试验、微波致裂过程中的温度、岩石破裂动态监测及微波功率和微波加热时间的智能化调控。

Description

一种基于真三轴应力下的微波智能加载致裂硬岩试验系统 技术领域
本发明涉及岩石力学实验装置技术领域，特别涉及一种基于真三轴应力下的微波智能加载致裂硬岩试验系统。
 背景技术
在采矿、交通隧道、水力水电厂房、引水隧洞、石油钻井等硬岩工程中，机械法破岩（TBM、掘进机、深井钻机）经常遭遇割不动、钻不动及刀具、钻头磨损严重的问题，增加了施工成本及降低了施工进度，制约了机械法破岩在上述工程中的应用。工程实践表明，TBM开挖坚硬岩体时，刀具的检查、维修、更换约占总施工时间的1/3，刀具费用也约占总施工成本的1/3。微波辅助机械破岩被认为是一种具有较好应用前景的新破岩技术，受到国内外学者的广泛关注。微波预先处理坚硬岩体，降低岩体力学性质如单轴强度、抗拉强度、断裂韧性等，然后再采用机械法进行破裂岩石，可提高破岩效率及降低破岩成本。以往研究中均是在无应力状态下进行的，而工程岩体多处于三向不等应力状态，开挖过程中会经历复杂的应力调整，三向应力会显著影响岩体的强度及变形特征，因此，需要研究真三轴应力下的微波致裂岩体特征及机制。
进行微波致裂硬岩时会产生较强的电磁场，容易造成电传感器输出信号失真或者击穿烧坏电子元件，难以获取微波致裂硬岩过程中的温升、破裂过程、破裂程度，也难以评价微波致裂岩石的效果，需要开发一种强微波场下的岩石热响应与破裂过程动态监测。在工程应用中，当以恒定微波功率、加热时间状态下致裂硬岩，容易使微波致裂岩体程度不足或者过度，造成致裂效率不高或者微波能浪费，急需将岩石温升、破裂程度、破裂发展趋势与微波功率、加热时间联系起来，实现微波功率、加热时间智能动态调控，提高微波能利用率及致裂效率。
 技术解决方案
为了解决现有技术存在的技术问题，本发明提供了一种基于真三轴应力下的微波智能加载致裂硬岩试验系统，其能够实现在真三轴应力下的微波致裂硬岩试验，能够实现微波辐射过程中的微波防护，并实现微波功率和微波加热时间的智能化调控。
为了实现上述目的，本发明的技术方案是：
一种基于真三轴应力下的微波智能加载致裂硬岩试验系统，包括真三轴硬岩微波致裂装置、岩石响应动态监测与微波参数智能调控系统、控制器和计算机，所述真三轴硬岩微波致裂装置包括真三轴应力加载装置和硬岩微波致裂装置；
所述真三轴应力加载装置包括加载框架以及设置于加载框架的岩样移动结构，所述加载框架包括上水平框架、下水平框架、左垂直框架、右垂直框架以及设置于下水平框架上方的横向框架，所述横向框架包括通过4根拉杆连接的前加载板和后加载板，所述下水平框架的侧面设置有装样台；所述上水平框架的下方安装Y向荷载千斤顶，用于承载Y方向的反作用力；所述左垂直框架靠近岩样的一侧安装X向荷载千斤顶，用于承载X方向的反作用力；所述后加载板安装有Z向荷载千斤顶，用于承载Z方向的反作用力；所述下水平框架的顶部、X向荷载千斤顶、Y向荷载千斤顶和Z向荷载千斤顶之间的空间构成用于放置岩样的三轴压力室；
所述硬岩微波致裂装置包括激励腔、矩形波导、磁控管、热电偶、环形器、冷水循环、流量计、功率计、自动阻抗调谐器、耦合器、微波加热器和屏蔽腔，所述矩形波导的一端与激励腔连接，所述矩形波导的另一端与微波加热器连接，所述矩形波导上依次设置环形器、耦合器和阻抗自动调谐器；所述磁控管安装于激励腔内部，并与微波电源连接，所述磁控管还依次与冷水循环和流量计连接，流量计用于监测和显示冷水的流量；所述环形器依次与水负载和热电偶连接，热电偶用于监测和显示水负载的温度；所述耦合器分别与功率计和阻抗自动调谐器连接；所述屏蔽腔设置于矩形波导的外部，并与前加载板固定连接，用于屏蔽未被岩样吸收的电磁能；
所述岩石响应动态监测与微波参数智能调控系统包括CCD工业相机、温度采集装置和防电磁耐高温声波-声发射一体化传感器；所述CCD工业相机实时记录微波致裂过程中的图像并传输到计算机保存和显示；所述温度采集装置采集岩石实时温度并传输到计算机保存和显示；所述防电磁耐高温声波-声发射一体化传感器与声发射仪连接，所述防电磁耐高温声波-声发射一体化传感器监测岩石实时波速和声发射并通过声发射仪传输到计算机保存和显示；计算机的内嵌程序根据岩石实时波速和声发射计算波速降、声发射累计数和声发射率，并把岩石实时温度、波速降、声发射累计数和声发射率发送至控制器，控制器根据波速降、岩石实时温度、声发射累计数和声发射率调整调整微波功率与微波加热时间。
进一步的，所述岩样移动结构包括移动式悬臂吊、Z向推移千斤顶和X向推移千斤顶，所述移动式悬臂吊连接于上水平框架的顶部，用于将岩样吊运或者吊离装样台；所述Z向推移千斤顶设置于装样台的上方，用于将岩样推至或者迁离右垂直框架的侧面；所述X向推移千斤顶设置于右垂直框架的内部，用于将右垂直框架侧面的岩样推至或者迁离三轴压力室。
进一步的，所述X向荷载千斤顶、Y向荷载千斤顶和Z向荷载千斤顶的油缸侧壁均分别安装有压力传感器，三个压力传感器均分别与计算机连接，将压力数据传输到计算机保存和显示。
进一步的，所述前加载板的中部开设矩形孔，所述矩形孔的长和宽均分别大于岩样前表面的长和宽，使岩样的微波辐射面完全不与前加载板接触。
进一步的，矩形波导穿过屏蔽腔并与屏蔽腔通过铝箔胶带和软质金属网连接。
进一步的，所述微波加热器采用微波表面加热器或者微波孔内加热器。
进一步的，所述温度采集装置为安装于岩样前方的红外热成像仪或者安装于岩样孔壁的分布式高温光纤；所述红外热成像仪采集岩石表面实时温度并传输到计算机保存和显示；所述分布式高温光纤与解调仪连接，所述分布式高温光纤采集岩石孔壁实时温度，岩石孔壁实时温度通过解调仪解调后传输到计算机保存和显示。
进一步的，所述红外热成像仪和CCD工业相机均分别设置于屏蔽盒内，所述屏蔽盒与截止圆波导连接，所述截止圆波导伸入到屏蔽腔内。
进一步的，所述防电磁耐高温声波-声发射一体化传感器包括压电元件、封装于压电元件外部的金属外壳和包裹于金属外壳外部的聚四氟乙烯隔热套；所述金属外壳的前端连接石英质引波杆，石英质引波杆与岩样表面直接接触，所述压电元件与屏蔽线连接。
进一步的，所述岩石响应动态监测与微波参数智能调控系统调整微波功率与微波加热时间的具体过程包括：
首先，计算机通过内嵌程序预设微波初始功率、微波初始加热时间、岩石初始波速和波速降阈值，并将上述参数传输至控制器，控制器内置声发射累计数阈值、声发射率阈值、岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、裂纹失稳扩展起始点的加热时间和裂纹失稳扩展时间，控制器控制微波电源以预设的微波初始功率和微波初始加热时间进行致裂岩石；
其次，在致裂岩石过程中，防电磁耐高温声波-声发射一体化传感器监测岩石实时波速和声发射，并将岩石实时波速和声发射发送到计算机，同时，温度采集装置采集岩石实时温度并传输到计算机；
最后，计算机通过内嵌程序将岩石初始波速减去岩石实时波速得到波速降，并对采集的声发射计数累加得到声发射累计数，再计算1s内采集的声发射计数得到声发射率，计算机把岩石实时温度、波速降、声发射累计数和声发射率传输至控制器，控制器将波速降与预设的波速降阈值进行比较，如果波速降大于等于波速降阈值，控制器控制微波电源停止加热以防止致裂过度；如果波速降小于波速降阈值，控制器将岩石实时温度、声发射累计数、声发射率分别与其内置的岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、声发射累计数阈值和声发射率阈值进行如下比较：
如果岩石温度低于岩石临界破裂点的温度，控制器控制微波电源保持微波初始功率和微波初始加热时间进行致裂岩石；
如果岩石温度高于等于岩石临界破裂点的温度，并且小于裂纹稳定扩展起始点的温度，则判断声发射累计数与声发射累计数阈值的关系，如果发射累计数小于声发射累计数阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果发射累计数高于等于声发射累计数阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；
如果岩石温度高于等于裂纹稳定扩展起始点的温度，并且小于裂纹失稳扩展起始点的温度，则判断声发射率与声发射率阈值的关系，如果声发射率小于声发射率阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果声发射率大于等于声发射率阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；
如果岩石温度高于等于裂纹失稳扩展起始点的温度，则判断声发射率与声发射率阈值的关系，如果声发射率小于声发射率阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果声发射率大于等于声发射率阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；同时，判断微波初始加热时间与裂纹失稳扩展起始点的加热时间的关系，如果微波初始加热时间小于等于裂纹失稳扩展起始点的加热时间，控制器控制微波电源延长微波加热时间；如果微波初始加热时间大于裂纹失稳扩展起始点的加热时间，计算微波初始加热时间与裂纹失稳扩展起始点的加热时间的差值，如果微波初始加热时间与裂纹失稳扩展起始点的加热时间的差值小于等于裂纹失稳扩展时间，控制器控制微波电源延长微波加热时间；如果微波初始加热时间与裂纹失稳扩展起始点的加热时间差值大于裂纹失稳扩展时间，控制器控制微波电源缩短微波加热时间。
 有益效果
1）本发明能够实现在真三轴应力下的微波致裂硬岩试验，通过真三轴应力加载装置能够实现五面压缩、单面临空（前面）的加载方式，用来模拟开挖面岩体所处的应力状态；
2）本发明在微波加载过程中采用冷水循环、热电偶、环形器、流量计、功率计、自动阻抗调谐器和屏蔽腔进行微波防护，保证硬岩微波致裂装置安全与稳定地运行；
3）本发明通过岩石响应动态监测与微波参数智能调控系统实现微波加热过程中的温度、硬岩破裂演化、硬岩破裂程度监测，以及微波功率和微波加热时间的智能调控，解决了工程应用中容易产生微波致裂岩体不足或者过度，造成致裂效率不高或者能量浪费的技术问题；
4）本发明通过岩石响应动态监测与微波参数智能调控系统能够实现微波致裂过程中的岩石温度、波速、声发射、图像监测，为后续实现微波致裂硬岩效果评价、破裂规律及机制研究提供数据。
本发明的其他特征和优点将在下面的具体实施方式中部分予以详细说明。
 附图说明
图1是本发明实施例提供的一种基于真三轴应力下的微波智能加载致裂硬岩试验系统的立体图一；
图2是本发明实施例提供的一种基于真三轴应力下的微波智能加载致裂硬岩试验系统的立体图二；
图3是本发明实施例提供的一种基于真三轴应力下的微波智能加载致裂硬岩试验系统的侧视图；
图4是本发明实施例提供的真三轴应力加载装置的剖视图；
图5是本发明实施例提供的强微波场下的岩石响应动态监测系统的结构示意图；
图6是本发明实施例提供的防电磁耐高温声波-声发射一体化传感器的结构示意图；
图7是本发明实施例提供的岩石响应动态监测与微波参数智能调控系统调整微波功率与微波加热时间的的原理图。
说明书附图中的附图标记包括：
1-移动式悬臂吊、2-上水平框架、3-Y向荷载千斤顶、4-Y向位移传感器、5- Z向位移传感器、6-拉杆、7- Z向荷载千斤顶、8-后加载板、9-Z向压力传感器、10-装样台、11-下水平框架、12-岩样、13-屏蔽腔、14-微波表面加热器、15-矩形波导、16-前加载板、17-Y向压力传感器、18-阻抗自动调谐器、19-功率计、20-耦合器、21-环形器、22-水负载、23-磁控管、24-激励腔、25-冷水循环、26-流量计、27-热电偶、28-升降平台、29-左垂直框架、30-X向荷载千斤顶、31-活塞压头、32-三轴压力室、33-刚性压板、34-活动压块、35-右垂直框架、36- X向推移千斤顶、37-Z向推移千斤顶、38-横向框架、39- X向位移传感器、40-X向压力传感器、41-岩样装载路线、42-岩样卸载路线、43- CCD工业相机、44-屏蔽盒、45-红外热成像仪、46-防电磁耐高温声波-声发射一体化传感器、47-声发射仪、48-解调仪、49-计算机、50-分布式高温光纤、51-微波孔内加热器、52-安装压板、53-石英质引波杆、54-压电元件、55-聚四氟乙烯隔热套、56-金属外壳、57-接头、58-屏蔽线。
 本发明的实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明的一部分实施例，而不是全部的实施例。
在本发明的描述中，需要理解的是，术语“纵向”、“横向”、“竖向”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”“内”、“外”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本发明和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本发明的限制。
在本发明的描述中，除非另有规定和限定，需要说明的是，术语“安装”、“相连”、“连接”应做广义理解，例如，可以是机械连接或电连接，也可以是两个元件内部的连通，可以是直接相连，也可以通过中间媒介间接相连，对于本领域的普通技术人员而言，可以根据具体情况理解上述术语的具体含义。
为了解决现有技术存在的问题，如图1至图7所示，本发明提供了一种基于真三轴应力下的微波智能加载致裂硬岩试验系统，包括真三轴硬岩微波致裂装置、岩石响应动态监测与微波参数智能调控系统、控制器（图中未示出）和计算机49，真三轴硬岩微波致裂装置包括真三轴应力加载装置和硬岩微波致裂装置；
真三轴应力加载装置包括加载框架以及设置于加载框架的岩样移动结构，加载框架包括上水平框架2、下水平框架11、左垂直框架29、右垂直框架35以及设置于下水平框架11上方的横向框架38，横向框架38包括通过4根拉杆6连接的前加载板16和后加载板8，下水平框架11的侧面设置有装样台10；上水平框架2的下方安装Y向荷载千斤顶3，用于承载Y方向的反作用力；左垂直框架29靠近岩样12的一侧安装X向荷载千斤顶30，用于承载X方向的反作用力；后加载板8安装有Z向荷载千斤顶7，用于承载Z方向的反作用力；下水平框架11的顶部、X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7之间的空间构成用于放置岩样12的三轴压力室32；
硬岩微波致裂装置包括激励腔24、矩形波导15、磁控管23、热电偶27、环形器21、冷水循环25、流量计26、功率计19、自动阻抗调谐器、耦合器20、微波加热器和屏蔽腔13，矩形波导15的一端与激励腔24连接，矩形波导15的另一端与微波加热器连接，矩形波导15上依次设置环形器21、耦合器20和阻抗自动调谐器18；磁控管23安装于激励腔24内部，并与微波电源连接，磁控管23还依次与冷水循环25和流量计26连接，流量计26用于监测和显示冷水的流量；环形器21依次与水负载22和热电偶27连接，热电偶27用于监测和显示水负载22的温度；耦合器20分别与功率计19和阻抗自动调谐器18连接；屏蔽腔13设置于矩形波导15的外部，并与前加载板16固定连接，用于屏蔽未被岩样12吸收的电磁能；
岩石响应动态监测与微波参数智能调控系统包括安装于岩样12的CCD工业相机43、温度采集装置和防电磁耐高温声波-声发射一体化传感器46；CCD工业相机43实时记录微波致裂过程中的图像并传输到计算机49保存和显示；温度采集装置采集岩石实时温度并传输到计算机49保存和显示；防电磁耐高温声波-声发射一体化传感器46与声发射仪47连接，防电磁耐高温声波-声发射一体化传感器46监测岩石实时波速和声发射并通过声发射仪47传输到计算机49保存和显示；计算机49的内嵌程序根据岩石实时波速和声发射计算波速降、声发射累计数和声发射率，并把岩石实时温度、波速降、声发射累计数和声发射率发送至控制器，控制器根据波速降、岩石实时温度、声发射累计数和声发射率调整调整微波功率与微波加热时间。
如图1至图3所示，硬岩微波致裂装置放置在升降平台28上，使硬岩微波致裂装置能够前后、左右、上下移动，升降平台28采用现有技术。加载框架为三向应力提供反作用力，其左垂直框架29和右垂直框架35的顶部和底部分别与上水平框架2和下水平框架11通过螺栓连接。X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7均分别通过伺服控制系统进行控制，伺服控制系统采用现有技术，伺服控制系统与计算机49连接，计算机49通过伺服控制系统实现三个方向荷载的分别独立加卸载。Z向荷载千斤顶7进行应力加载时，岩样12通过其X方向和Y方向受到的摩擦力来保证其受力平衡，比如，当岩样12在X方向和Y方向的摩擦力系数小于0.5时，先通过X向荷载千斤顶30和Y向荷载千斤顶3进行加载，然后再通过Z向荷载千斤顶7施加Z方向的荷载，使X方向和Y方向的摩擦力始终大于Z向的荷载；当岩样12在X方向和Y方向的摩擦力系数大于等于0.5时，通过X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7以相同的加载速率同时加载；而在三向应力卸载时，应当首先卸载Z方向荷载，然后再逐步卸载X方向和Y方向的荷载。本发明的真三轴应力加载装置最大可适用边长为40cm的立方体岩样12，通过改变刚性压板33的尺寸来实现不同岩样12的试验。
本发明中，微波电源为磁控管23提供电力，磁控管23将电能转化为电磁能，激励腔24内磁控管23产生电磁波沿着矩形波导15传输，依次经过环形器21、耦合器20和阻抗自动调谐器18，最后经过微波加热器（微波表面加热器14或者微波孔内加热器51）辐射至岩样12（表面或孔内）。阻抗自动调谐器18采用现有技术，其能够自动检测岩样12负载阻抗，并及时地调整微波致裂装置阻抗，与岩样12负载阻抗达到最大程度的匹配，以降低微波反射功率。屏蔽腔13为四周封闭的金属箱体，为真三轴应力加载装置与硬岩微波致裂装置的中间连接件，其与前加载板16固定连接，屏蔽未被岩样12吸收的电磁能，将电磁波限制在屏蔽腔13内。
岩样12移动结构包括移动式悬臂吊1、Z向推移千斤顶37和X向推移千斤顶36，移动式悬臂吊1连接于上水平框架2的顶部，用于将岩样12吊运或者吊离装样台10；Z向推移千斤顶37设置于装样台10的上方，用于将岩样12推至或者迁离右垂直框架35的侧面；X向推移千斤顶36设置于右垂直框架35的内部，用于将右垂直框架35侧面的岩样12推至或者迁离三轴压力室32。
本发明中，移动式悬臂吊1采用现有技术，并且右垂直框架35靠近岩样12的一侧设置有导轨以及可沿导轨上下移动的活动压块34，如图4所示的岩样装载路线41和岩样卸载路线42，岩样12装载时，将活动压块34沿导轨向上移动并固定，移动式悬臂吊1将岩样12吊运至装样台10上，然后通过Z向推移千斤顶37和X向推移千斤顶36将岩样12推移至三轴压力室32内，再将活动压块34沿导轨下移至装样台10上，作为X向应力的被动端，活动压块34与岩样12间放置有刚性压板33，在实际操作中，通过遥控器控制X向推移千斤顶36和Z向推移千斤顶37进行工作；卸载岩样12时，将活动压块34沿导轨向上移动并固定，X向推移千斤顶36将岩样12沿X方向移出，再使用Z向推移千斤顶37将岩样12沿Z方向移出，最后通过移动式悬臂吊1将岩样12吊离装样台10。
X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7的油缸侧壁均分别安装有压力传感器，X向压力传感器40、Y向压力传感器17和Z向压力传感器9均分别与计算机49连接，将压力数据传输到计算机49保存和显示，三个压力传感器分别用于监测X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7的油缸的压力，通过各个油缸的压力分别得到各向荷载千斤顶加载到岩样12的荷载；X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7的活塞压头31上均分别安装有位移传感器，X向位移传感器39、Y向位移传感器4和Z向位移传感器5均分别与计算机49连接，将位移数据传输到计算机49，三个位移传感器分别用于监测X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7的活塞的移动，通过各个荷载千斤顶活塞的移动分别得到岩样12的各个方向位移；计算机49将三个千斤顶的实时压力数据分别与各自的设定压力进行比较，并将三个千斤顶的实时位移数据分别与各自的设定位移进行比较，再通过伺服控制系统分别控制X向荷载千斤顶30、Y向荷载千斤顶3和Z向荷载千斤顶7实现三个方向的独立加卸载。
前加载板16的中部开设矩形孔，矩形孔的长和宽均分别大于岩样12前表面的长和宽，使岩样12的微波辐射面（即岩样12前表面）完全不与前加载板16接触。
矩形波导15穿过屏蔽腔13并与屏蔽腔13通过铝箔胶带和软质金属网连接，防止电磁波从两者连接处泄露，在实际试验时，岩样12的空白角、岩样12与各加载构件之间以及各加载构件之间的缝隙均采用铝箔胶带，软质金属网和磁性元件，或者铝箔胶带、软质金属网和磁性元件进行填充、密封、固定，防止电磁波从以上空隙处泄露，实现微波辐射与真三轴应力加载的耦合。
微波加热器采用微波表面加热器14或者微波孔内加热器51，微波加热器用于定向辐射微波能，微波表面加热器14可表面致裂岩石以辅助机械破碎硬岩，微波孔内加热器51可在钻孔内致裂硬岩以降低岩爆风险。
温度采集装置为安装于岩样12前方的红外热成像仪45或者安装于岩样12孔壁的分布式高温光纤50；红外热成像仪45采集岩石表面实时温度并传输到计算机49保存和显示；分布式高温光纤50与解调仪48连接，分布式高温光纤50采集岩石孔壁实时温度，岩石孔壁实时温度通过解调仪48解调后传输到计算机49保存和显示。
红外热成像仪45和CCD工业相机43均分别设置于屏蔽盒44内，屏蔽盒44与截止圆波导连接，截止圆波导伸入到屏蔽腔13内。具体的，屏蔽盒44为连有截止圆波导的封闭金属盒，与屏蔽盒44连接的截止圆波导既可用于屏蔽电磁波，又可以作为信息监测的观察孔，截止圆波导与屏蔽腔13之间采用铝箔纸连接；微波表面致裂时，安装在屏蔽盒44内的红外热成像仪45能够采集岩石表面实时温度；安装在屏蔽盒44内的CCD工业相机43能够监测岩石的破裂过程。
如图5所示，计算机49分别与CCD工业相机43、温度采集装置、声发射仪47和控制器连接，控制器与微波电源连接，温度采集装置为红外热成像仪45时，计算机49与红外热成像仪45连接；温度采集装置为分布式高温光纤50时，计算机49与解调仪48连接。CCD工业相机43安装在岩样12的正对面，用于监测岩石的破裂过程，CCD工业相机43实时记录微波致裂过程中的图像，在后续处理中，利用二维数字散斑技术分析微波致裂过程中的图像得到岩石的变形规律。微波孔内致裂硬岩时，将红外热成像仪45安装在岩样12前方的正面或者侧面，实时监测岩石表面温度；或者采用分布式光纤测温技术，即通过屏蔽腔13内部的分布式高温光纤50和屏蔽腔13外部的解调仪48进行测温，分布式高温光纤50的一端固定在岩样12孔壁，另一端与解调仪48连接，解调仪48与计算机49连接，完全不受强电磁场的影响，监测岩样12孔壁温度时，分布式高温光纤50采用高温胶布在岩样12孔内进行多点式固定，保证与岩样12孔壁保持紧密接触。微波致裂硬岩时会在岩石表面产生强电磁场与高温，而强电磁场和高温会对波速、声发射的采集产生较大的干扰，采用防电磁耐高温声波-声发射一体化传感器46能够避免强电磁场和高温干扰，来采集岩石波速和声发射活动。
防电磁耐高温声波-声发射一体化传感器46包括压电元件54、封装于压电元件54外部的金属外壳56和包裹于金属外壳56外部的聚四氟乙烯隔热套55；金属外壳56的前端连接石英质引波杆53，石英质引波杆53与岩样12表面直接接触，压电元件54与屏蔽线58连接。如图6所示，压电元件54采用金属外壳56封装，金属壳外部采用聚四氟乙烯隔热套55包裹，能够屏蔽强电磁场及高温的干扰，金属外壳56前端连接的石英质引波杆53直接接触岩样12表面，最高可耐400 ℃，屏蔽线58用于与声发射仪47连接，屏蔽线58穿过金属外壳56和聚四氟乙烯隔热套55部分的外部设置有接头57，接头57用于保护屏蔽线58。在实际试验时，防电磁耐高温声波-声发射一体化传感器46通过安装压板52设置于岩样12表面，岩样12除前面和底面外，其他四个面均设置有岩样12表面直接接触的安装压板52，安装压板52设置有引线槽和贯穿孔，引线槽位于安装压板52远离岩样12的一侧，即使引线槽不靠近岩样12表面；贯穿孔内放置防电磁耐高温声波-声发射一体化传感器46。在实际试验时，每个安装压板52远离岩样12的一侧还设置有至少一个刚性压板33（不用固定）。
如图7所示，岩石响应动态监测与微波参数智能调控系统调整微波功率与微波加热时间的具体过程包括：
首先，计算机49通过内嵌程序预设微波初始功率、微波初始加热时间、岩石初始波速和波速降阈值，并将上述参数传输至控制器，控制器内置声发射累计数阈值、声发射率阈值、岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、裂纹失稳扩展起始点的加热时间和裂纹失稳扩展时间，控制器控制微波电源以预设的微波初始功率和微波初始加热时间进行致裂岩石；
其次，在致裂岩石过程中，防电磁耐高温声波-声发射一体化传感器46监测岩石实时波速和声发射，并将岩石实时波速和声发射发送到计算机49，同时，温度采集装置采集岩石实时温度并传输到计算机49；
最后，计算机49通过内嵌程序将岩石初始波速减去岩石实时波速得到波速降，并对采集的声发射计数累加得到声发射累计数，再计算1s内采集的声发射计数得到声发射率，计算机49把岩石实时温度、波速降、声发射累计数和声发射率传输至控制器，控制器将波速降与预设的波速降阈值进行比较，如果波速降大于等于波速降阈值，控制器控制微波电源停止加热以防止致裂过度；如果波速降小于波速降阈值，控制器将岩石实时温度、声发射累计数、声发射率分别与其内置的岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、声发射累计数阈值和声发射率阈值进行如下比较：
如果岩石温度低于岩石临界破裂点的温度，控制器控制微波电源保持微波初始功率和微波初始加热时间进行致裂岩石；
如果岩石温度高于等于岩石临界破裂点的温度，并且小于裂纹稳定扩展起始点的温度，则判断声发射累计数与声发射累计数阈值的关系，如果发射累计数小于声发射累计数阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果发射累计数高于等于声发射累计数阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；
如果岩石温度高于等于裂纹稳定扩展起始点的温度，并且小于裂纹失稳扩展起始点的温度，则判断声发射率与声发射率阈值的关系，如果声发射率小于声发射率阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果声发射率大于等于声发射率阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；
如果岩石温度高于等于裂纹失稳扩展起始点的温度，则判断声发射率与声发射率阈值的关系，如果声发射率小于声发射率阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果声发射率大于等于声发射率阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；同时，判断微波初始加热时间与裂纹失稳扩展起始点的加热时间的关系，如果微波初始加热时间小于等于裂纹失稳扩展起始点的加热时间，控制器控制微波电源延长微波加热时间；如果微波初始加热时间大于裂纹失稳扩展起始点的加热时间，计算微波初始加热时间与裂纹失稳扩展起始点的加热时间的差值，如果微波初始加热时间与裂纹失稳扩展起始点的加热时间的差值小于等于裂纹失稳扩展时间（0-60s），控制器控制微波电源延长微波加热时间；如果微波初始加热时间与裂纹失稳扩展起始点的加热时间差值大于裂纹失稳扩展时间（0-60s），控制器控制微波电源缩短微波加热时间。
本发明中，为了获取岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、裂纹失稳扩展起始点的加热时间、裂纹失稳扩展时间、声发射累计数阈值和声发射率阈值，需要预先进行大量的微波致裂试验，得到岩石实时温度与声发射累计数的关系图、岩石实时温度与声发射率的关系图、岩石实时温度与微波功率和微波加热时间的关系图，根据上述关系图即可得到岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、裂纹失稳扩展起始点的加热时间、裂纹失稳扩展时间、声发射累计数阈值和声发射率阈值。
本发明中，岩石响应动态监测与微波参数智能调控系统能够实时监测微波致裂过程中的温度、岩石破裂过程，为后续评价微波致裂岩石效果提供数据。岩石破裂时会发生波速降低和声发射，岩石响应动态监测与微波参数智能调控系统根据温度与声发射的动态反馈来主动调控微波功率与微波加热时间，例如：破裂过度时便停止加热、破裂不足时便提高微波功率，实现适用于工程现场及室内试验的微波智能加载致裂硬岩，提高微波致裂硬岩效率与微波能利用率。由于微波致裂程度与微波功率和微波加热时间有关，而声发射和温度能够描述岩石的破裂的过程，波速降为岩石破裂程度的反馈指标，用来评价微波致裂岩石效果，声发射累计数和声发射率为岩石破裂发展的反馈指标，红外热成像仪45或分布式高温光纤50所监测的岩石实时温度可用来研究岩石的升温特性，由温度确定岩石发生破裂的条件，因此，本发明根据温度和声发射来判断岩石破裂的趋势及阶段。
尽管已经示出和描述了本发明的实施例，本领域的普通技术人员可以理解：在不脱离本发明的原理和宗旨的情况下可以对这些实施例进行多种变化、修改、替换和变型，本发明的范围由权利要求及其等同物限定。

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  1. 一种基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，包括真三轴硬岩微波致裂装置、岩石响应动态监测与微波参数智能调控系统、控制器和计算机，所述真三轴硬岩微波致裂装置包括真三轴应力加载装置和硬岩微波致裂装置；
    所述真三轴应力加载装置包括加载框架以及设置于加载框架的岩样移动结构，所述加载框架包括上水平框架、下水平框架、左垂直框架、右垂直框架以及设置于下水平框架上方的横向框架，所述横向框架包括通过4根拉杆连接的前加载板和后加载板，所述下水平框架的侧面设置有装样台；所述上水平框架的下方安装Y向荷载千斤顶，用于承载Y方向的反作用力；所述左垂直框架靠近岩样的一侧安装X向荷载千斤顶，用于承载X方向的反作用力；所述后加载板安装有Z向荷载千斤顶，用于承载Z方向的反作用力；所述下水平框架的顶部、X向荷载千斤顶、Y向荷载千斤顶和Z向荷载千斤顶之间的空间构成用于放置岩样的三轴压力室；
    所述硬岩微波致裂装置包括激励腔、矩形波导、磁控管、热电偶、环形器、冷水循环、流量计、功率计、自动阻抗调谐器、耦合器、微波加热器和屏蔽腔，所述矩形波导的一端与激励腔连接，所述矩形波导的另一端与微波加热器连接，所述矩形波导上依次设置环形器、耦合器和阻抗自动调谐器；所述磁控管安装于激励腔内部，并与微波电源连接，所述磁控管还依次与冷水循环和流量计连接，流量计用于监测和显示冷水的流量；所述环形器依次与水负载和热电偶连接，热电偶用于监测和显示水负载的温度；所述耦合器分别与功率计和阻抗自动调谐器连接；所述屏蔽腔设置于矩形波导的外部，并与前加载板固定连接，用于屏蔽未被岩样吸收的电磁能；
    所述岩石响应动态监测与微波参数智能调控系统包括CCD工业相机、温度采集装置和防电磁耐高温声波-声发射一体化传感器；所述CCD工业相机实时记录微波致裂过程中的图像并传输到计算机保存和显示；所述温度采集装置采集岩石实时温度并传输到计算机保存和显示；所述防电磁耐高温声波-声发射一体化传感器与声发射仪连接，所述防电磁耐高温声波-声发射一体化传感器监测岩石实时波速和声发射并通过声发射仪传输到计算机保存和显示；计算机的内嵌程序根据岩石实时波速和声发射计算波速降、声发射累计数和声发射率，并把岩石实时温度、波速降、声发射累计数和声发射率发送至控制器，控制器根据波速降、岩石实时温度、声发射累计数和声发射率调整调整微波功率与微波加热时间。
  2. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述岩样移动结构包括移动式悬臂吊、Z向推移千斤顶和X向推移千斤顶，所述移动式悬臂吊连接于上水平框架的顶部，用于将岩样吊运或者吊离装样台；所述Z向推移千斤顶设置于装样台的上方，用于将岩样推至或者迁离右垂直框架的侧面；所述X向推移千斤顶设置于右垂直框架的内部，用于将右垂直框架侧面的岩样推至或者迁离三轴压力室。
  3. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述X向荷载千斤顶、Y向荷载千斤顶和Z向荷载千斤顶的油缸侧壁均分别安装有压力传感器，三个压力传感器均分别与计算机连接，将压力数据传输到计算机保存和显示。
  4. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述前加载板的中部开设矩形孔，所述矩形孔的长和宽均分别大于岩样前表面的长和宽。
  5. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，矩形波导穿过屏蔽腔并与屏蔽腔通过铝箔胶带和软质金属网连接。
  6. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述微波加热器采用微波表面加热器或者微波孔内加热器。
  7. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述温度采集装置为安装于岩样前方的红外热成像仪或者安装于岩样孔壁的分布式高温光纤；所述红外热成像仪采集岩石表面实时温度并传输到计算机保存和显示；所述分布式高温光纤与解调仪连接，所述分布式高温光纤采集岩石孔壁实时温度，岩石孔壁实时温度通过解调仪解调后传输到计算机保存和显示。
  8. 根据权利要求7所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述红外热成像仪和CCD工业相机均分别设置于屏蔽盒内，所述屏蔽盒与截止圆波导连接，所述截止圆波导伸入到屏蔽腔内。
  9. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述防电磁耐高温声波-声发射一体化传感器包括压电元件、封装于压电元件外部的金属外壳和包裹于金属外壳外部的聚四氟乙烯套；所述金属外壳的前端连接石英质引波杆，石英质引波杆与岩样表面直接接触，所述压电元件与屏蔽线连接。
  10. 根据权利要求1所述的基于真三轴应力下的微波智能加载致裂硬岩试验系统，其特征在于，所述岩石响应动态监测与微波参数智能调控系统调整微波功率与微波加热时间的具体过程包括：
    首先，计算机通过内嵌程序预设微波初始功率、微波初始加热时间、岩石初始波速和波速降阈值，并将上述参数传输至控制器，控制器内置声发射累计数阈值、声发射率阈值、岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、裂纹失稳扩展起始点的加热时间和裂纹失稳扩展时间，控制器控制微波电源以预设的微波初始功率和微波初始加热时间进行致裂岩石；
    其次，在致裂岩石过程中，防电磁耐高温声波-声发射一体化传感器监测岩石实时波速和声发射，并将岩石实时波速和声发射发送到计算机，同时，温度采集装置采集岩石实时温度并传输到计算机；
    最后，计算机通过内嵌程序将岩石初始波速减去岩石实时波速得到波速降，并对采集的声发射计数累加得到声发射累计数，再计算1s内采集的声发射计数得到声发射率，计算机把岩石实时温度、波速降、声发射累计数和声发射率传输至控制器，控制器将波速降与预设的波速降阈值进行比较，如果波速降大于等于波速降阈值，控制器控制微波电源停止加热以防止致裂过度；如果波速降小于波速降阈值，控制器将岩石实时温度、声发射累计数、声发射率分别与其内置的岩石临界破裂点的温度、裂纹稳定扩展起始点的温度、裂纹失稳扩展起始点的温度、声发射累计数阈值和声发射率阈值进行如下比较：
    如果岩石温度低于岩石临界破裂点的温度，控制器控制微波电源保持微波初始功率和微波初始加热时间进行致裂岩石；
    如果岩石温度高于等于岩石临界破裂点的温度，并且小于裂纹稳定扩展起始点的温度，则判断声发射累计数与声发射累计数阈值的关系，如果发射累计数小于声发射累计数阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果发射累计数高于等于声发射累计数阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；
    如果岩石温度高于等于裂纹稳定扩展起始点的温度，并且小于裂纹失稳扩展起始点的温度，则判断声发射率与声发射率阈值的关系，如果声发射率小于声发射率阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果声发射率大于等于声发射率阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；
    如果岩石温度高于等于裂纹失稳扩展起始点的温度，则判断声发射率与声发射率阈值的关系，如果声发射率小于声发射率阈值，说明微波初始功率不足，控制器控制微波电源提高微波功率进行致裂岩石；如果声发射率大于等于声发射率阈值，说明微波初始功率足够，控制器控制微波电源保持微波初始功率继续致裂岩石；同时，判断微波初始加热时间与裂纹失稳扩展起始点的加热时间的关系，如果微波初始加热时间小于等于裂纹失稳扩展起始点的加热时间，控制器控制微波电源延长微波加热时间；如果微波初始加热时间大于裂纹失稳扩展起始点的加热时间，计算微波初始加热时间与裂纹失稳扩展起始点的加热时间的差值，如果微波初始加热时间与裂纹失稳扩展起始点的加热时间的差值小于等于裂纹失稳扩展时间，控制器控制微波电源延长微波加热时间；如果微波初始加热时间与裂纹失稳扩展起始点的加热时间差值大于裂纹失稳扩展时间，控制器控制微波电源缩短微波加热时间。
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