A test platform and method for simulating high and low temperature cycle rock breaking at a tunnel face

Abstract

The present invention relates to the technical field of rock mass mechanics testing, and in particular to a high-low temperature cycle rock breaking test platform and method for simulating a tunnel face, wherein the high-low temperature cycle rock breaking test platform for simulating a tunnel face comprises a working platform, a gantry frame and a loading module, wherein the working platform is arranged at the bottom of the gantry frame for carrying a rock sample, and the loading module is installed above the gantry frame for simulating rock breaking of the rock sample; a heat insulation device is arranged at the upper part of the working platform, and the heat insulation device comprises a frame of a hollow structure, wherein a cooling flow channel is formed in the frame, and is used to insulate the side and bottom surfaces of the rock sample, aiming to simulate the complex interaction and destruction law of thermal-mechanical coupling of a roller cutter-tunnel face of a deep extremely hard rock formation, and solves the problem that the existing high-temperature rock heating device cannot realize precise line and surface heating of rock samples.

Description

Technical Field

[0001] The invention relates to the technical field of rock mass mechanics testing, and in particular to a platform and method for simulating high and low temperature cycle rock breaking testing of a tunnel face. Background Art

[0002] When a full-face hard rock tunnel boring machine (TBM) encounters extremely hard rock formations, it will inevitably encounter problems such as slow excavation rate and severe tool damage. In response to this typical problem, some researchers have proposed that pre-damage of the rock mass at the face by high and low temperature cycle treatment can reduce rock strength and improve rock excavability. For emerging research topics involving the complex interaction of thermal-mechanical coupling between TBM cutter and face rock, there are still many problems to be solved, and it is necessary to study the characteristics of the face failure mechanism after high and low temperature cycles in the laboratory. The heating test methods currently conducted in the laboratory are mature, such as the traditional muffle furnace device. However, it is still impossible to achieve surface and line heating of rock samples, it is impossible to simulate the actual heating of the face during the TBM rock breaking process, and it is impossible to provide experimental results with reference value for actual engineering.

[0003] Therefore, in view of this, the inventors proposed a test platform and method that can simulate the high and low temperature cycle rock breaking of the tunnel face, providing a basic test device and theoretical guidance for the development of thermal damage assisted TBM rock breaking technology. Summary of the invention

[0004] The purpose of the present invention is to provide a simulated tunnel face high and low temperature cycle rock breaking test platform, aiming to simulate the complex interaction and destruction law of thermal-mechanical coupling between the cutter and the tunnel face rock in deep extremely hard rock formations, and to solve the problem that the existing high-temperature rock heating device cannot achieve precise line and surface heating of rock samples; on the other hand, the present invention also proposes a method.

[0005] In order to achieve the above object, on the one hand, the technical solution adopted by the present invention is as follows:

[0006] A simulated tunnel face high and low temperature cycle rock breaking test platform, comprising a working platform, a gantry frame and a loading module, wherein the working platform is arranged at the bottom of the gantry frame for carrying rock samples, and the loading module is installed above the gantry frame for simulating rock breaking of rock samples;

[0007] A heat insulation device is arranged on the upper part of the working platform, and the heat insulation device comprises a frame of a hollow structure, and a cooling flow channel is formed in the frame, which is used to insulate the side and bottom surfaces of the rock sample;

[0008] It also includes a mechanized heat-insulating shell covering the outer periphery of the heat-insulating device and a temperature control unit arranged on the mechanized heat-insulating shell, wherein the number of the temperature control units is multiple;

[0009] The temperature control unit includes a high temperature resistant telescopic rod, a heating module and a cooling module. The high temperature resistant telescopic rod is connected to the heating module and the cooling module respectively, and the high temperature resistant telescopic rod can drive the heating module and the cooling module to approach or move away from the surface of the rock sample.

[0010] Furthermore, the heat insulation device further comprises a ceramic fiber polycrystalline mullite plate, and the ceramic fiber polycrystalline mullite plate is attached to the outside and / or inside of the frame;

[0011] A plurality of stainless steel grids are arranged inside the frame, and each of the stainless steel grids is distributed in an "S" shape inside the frame;

[0012] A water inlet and a water outlet are provided at the bottom of the frame, and both the water inlet and the water outlet are communicated with the inner cavity of the working platform.

[0013] Furthermore, a water inlet channel and a water outlet channel are arranged inside the working platform, the water inlet channel is connected to the water inlet of the frame, and the water outlet channel is connected to the water outlet of the frame;

[0014] The water inlet channel is connected with a water pipe, the water pipe is connected with a water tank, and the water pipe is provided with an application metering pump.

[0015] Furthermore, a base is provided on the gantry frame, a brake module is installed at the bottom of the working platform, and the brake module is provided on the base;

[0016] The braking module includes a horizontal support arranged on a base, a mounting gear is arranged on the horizontal support, a gear guide rail and a servo motor are arranged inside the base, and the gear guide rail is meshed with the mounting gear; a threaded conduit is rotatably connected to the base, the threaded conduit is threadedly connected to the working platform, and the threaded conduit is connected to the servo motor.

[0017] Furthermore, the mechanized heat-insulating housing comprises a housing 1, a housing 2 and an upper cover plate, both sides of the housing 1 and the housing 2 are connected with mechanical arms, and both the mechanical arms are provided with control motors;

[0018] The two motors are used to drive the corresponding two mechanical arms to move closer to or away from each other respectively;

[0019] Alumina felt and a ceramic liner are arranged inside the shell 1 and the shell 2, and a heat insulation sealing strip is arranged at the connection between the shell 1 and the shell 2.

[0020] Furthermore, the loading module includes a hydraulic cylinder fixedly mounted on the gantry frame, the hydraulic cylinder is located in the middle position of the gantry frame, the piston end of the hydraulic cylinder is connected to a movable crossbeam, a movable guide rail is arranged between the movable crossbeam and the gantry frame, the movable crossbeam and the gantry frame are connected through the movable guide rail, a sensor mounting frame is arranged at the lower part of the movable crossbeam; a three-axis force sensor is arranged at the lower part of the sensor mounting frame, a tool holder is connected to the three-axis force sensor, a disc-type roller is arranged on the tool holder, and the three-axis force sensor is used to monitor the force condition of the disc-shaped roller.

[0021] Further, the heating modules and the cooling modules are arranged alternately;

[0022] The heating module includes a resistance chamber and a heating resistance rod, wherein the heating resistance rod is arranged inside the resistance chamber, and the top of the resistance chamber is connected to a high temperature resistant telescopic rod;

[0023] The cooling module includes a delivery pipeline and a coolant nozzle, the coolant nozzle is suspended on the upper cover plate through a high-temperature resistant telescopic rod, the upper cover plate is provided with an infrared thermometer, the high-temperature resistant telescopic rod is equipped with an electric motor, the upper cover plate is provided with a built-in slide rail, and the electric motor is installed on the built-in slide rail.

[0024] Furthermore, the coolant nozzle includes a liquid nitrogen nozzle, a rotating arm, a water nozzle, a threaded flexible joint and a self-powered temperature regulating valve. The delivery pipeline is connected to the coolant nozzle through the threaded flexible joint. The rotating arm contains a temperature sensor, and a plurality of water nozzles are arranged outside the rotating arm, and the water nozzles are unevenly distributed.

[0025] Furthermore, a sleeve is sleeved on the rotating arm, and the sleeve can move on the rotating arm to open or close the water nozzle.

[0026] On the other hand, the present application also proposes a method for simulating high and low temperature cycle rock breaking test of a tunnel face, using the aforementioned simulated tunnel face high and low temperature cycle rock breaking test platform, comprising the following steps:

[0027] S1: Place the prepared rock sample into the thermal insulation device and start the mechanical arm to completely close the mechanized thermal insulation shell;

[0028] S2: Connect the water inlet channel on the working platform to the water source, the water outlet channel to the drain pipe, and the coolant channel to the coolant tank;

[0029] S3: Input the target temperature on the central console, select surface heating or line heating according to the test requirements, control the high temperature resistant telescopic rod and heating resistor rod, and monitor the temperature of each position of the rock sample in real time according to the feedback from the infrared thermometer;

[0030] S4: Turn on the heat insulation device, turn on the metering pump, calculate and input the corresponding water flow rate according to the target temperature, and let the water enter the heat insulation device at the preset flow rate;

[0031] S5: When the central console displays that the preset temperature has been reached, the heating resistor is turned off and the cooling module is started. Surface cooling or line cooling is selected according to the test requirements to achieve precise cooling of the rock sample.

[0032] S6: After the central console reaches room temperature, the mechanical arm is started to open the mechanized heat-insulated housing to expose the rock sample and place the rock sample under the loading module;

[0033] S7: Start the loading module, the hydraulic cylinder pushes the movable crossbeam, driving the disc cutter to move downward at a constant rate, and at the same time start the brake module installed at the bottom of the working platform to drive the working platform to start moving, so that the cutter rolls and breaks rocks, and obtains the three-dimensional force state of the disc cutter.

[0034] Beneficial effects of the present invention:

[0035] The present invention can simulate the high and low temperature cycle rock breaking effect of the face, realize the precise line and surface heating-cooling test of large-scale granite, and the test device platform can complete the collection of the three-dimensional force of the hob. Through the finely designed heating module, cooling module and thermal insulation device, the platform can accurately simulate the high and low temperature cycle changes of the rock sample during the TBM rock breaking process. The alternating setting and precise control of the heating module and the cooling module, combined with the design of the water nozzle, ensure the uniformity of the heating and cooling of the rock sample, and improve the accuracy of the experiment. At the same time, only the upper surface of the rock sample is heated, and the surrounding and bottom are cooled, which is more in line with the actual construction situation, making the experimental results more authentic, and providing valuable experimental data for scientific researchers; the platform not only has the basic functions of high and low temperature cycle rock breaking test, but also realizes the surface heating, line heating, surface cooling and line cooling of the heating and cooling module through the design of high temperature resistant telescopic rods, electric motors and other components. Multiple modes. This flexibility enables scientific researchers to flexibly adjust experimental parameters according to different research needs and conduct diversified experimental explorations. In addition, the hydraulic cylinder, movable crossbeam and three-way force sensor of the loading module enable the platform to simulate the rock-breaking process of the disc cutter and obtain the three-way force state of the disc cutter, further enhancing the versatility of the platform.

[0036] Other advantages, objectives and features of the present application will be described to some extent in the subsequent description, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present application. The objectives and other advantages of the present application can be achieved and obtained through the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1The overall diagram of the high and low temperature cycle rock breaking test platform for simulating the tunnel face provided by the present invention;

[0038] Figure 2 A top view of the lower brake module of the simulated tunnel face high and low temperature cycle rock breaking test platform provided by the present invention;

[0039] Figure 3 A schematic diagram of the interior of a heat insulation device of a simulated tunnel face high and low temperature cycle rock breaking test platform provided by the present invention;

[0040] Figure 4 A schematic diagram of a mechanized heat-insulating shell heating module of a simulated tunnel face high-low temperature cycle rock-breaking test platform provided by the present invention;

[0041] Figure 5 A schematic diagram of a mechanized heat-insulated housing cooling module for a simulated tunnel face high-low temperature cycle rock-breaking test platform provided by the present invention;

[0042] Figure 6 A bottom view of the mechanized heat-insulated shell of the high-low temperature cycle rock-breaking test platform for simulating the tunnel face provided by the present invention;

[0043] Figure 7 Detailed diagram of the coolant nozzle of the simulated tunnel face high and low temperature cycle rock breaking test platform provided by the present invention;

[0044] Figure 8 A schematic diagram of the structure of a mechanical arm and a control motor in a high-low temperature cycle rock breaking test platform for simulating a tunnel face provided by the present invention;

[0045] Fig. 9 Another structural schematic diagram of the mechanical arm and the control motor in the simulated tunnel face high and low temperature cycle rock breaking test platform provided by the present invention.

[0046] Among them, rock sample 1, shell 1 101, shell 2 102, mechanical arm 103, control motor 104, heating resistor rod 105, resistor compartment 106, high temperature resistant telescopic rod 107, conveying pipeline 108, coolant nozzle 109, liquid nitrogen nozzle 1091, rotating arm 1092, water nozzle 1093, threaded joint 1094, self-operated temperature regulating valve 1095, sleeve 1096, built-in slide rail 110, electric motor 112, working platform 2, metering pump 201, water inlet channel 202, water outlet channel 203, cooling Liquid channel 204, gantry frame 3, base 302, hydraulic cylinder 401, movable crossbeam 402, tool holder 403, disc-type hob 404, movable guide rail 405, three-way force sensor 406, sensor mounting bracket 407, thermal insulation device 5, frame 501, stainless steel grid 502, water inlet 503, water outlet 504, brake module 6, servo motor 601, threaded conduit 602, mounting gear 603, gear guide rail 604, horizontal support 605, ceramic fiber polycrystalline mullite plate 7, center console 8, infrared thermometer 9. DETAILED DESCRIPTION

[0047] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0048] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0049] This embodiment proposes a high-low temperature cycle rock breaking test platform for simulating a tunnel face, which is used to perform a high-low temperature cycle rock breaking test on a rock sample. Figures 1 to 9 As shown, it includes a working platform 2, a gantry frame 3 and a loading module. The working platform 2 is arranged at the bottom of the gantry frame 3 for carrying the rock sample 1. The loading module is installed above the gantry frame 3 for simulating rock breaking of the rock sample 1. A heat insulation device 5 is arranged on the upper part of the workbench, and the rock sample 1 is placed in the heat insulation device 5. The working platform 2 is hollow inside and is used for placing the water inlet pipe and the drain pipe of the heat insulation device 5.

[0050] The thermal insulation device 5 includes a hollow structure frame 501 and a ceramic fiber polycrystalline mullite plate 7. A cooling channel is formed in the frame 501. When the rock sample 1 is placed in the frame 501, the cooling channel is used to cool and insulate the side and bottom surfaces of the rock sample 1. The thermal insulation device 5 is provided with a mechanized thermal insulation shell and a temperature control unit arranged on the mechanized thermal insulation shell on the periphery. The number of the temperature control units is multiple. The temperature control unit includes a high temperature resistant telescopic rod 107, a heating module and a cooling module. The high temperature resistant telescopic rod 107 is connected to the heating module and the cooling module respectively. The high temperature resistant telescopic rod 107 can drive the heating module and the cooling module to approach or move away from the surface of the rock sample 1.

[0051] The ceramic fiber polycrystalline mullite plate 7 is attached to the outside and / or inside of the frame 501; in the present embodiment, the ceramic fiber polycrystalline mullite plate 7 is attached to the outside and inside of the frame 501, and the function of the ceramic fiber polycrystalline mullite plate 7 is to be used for heat insulation and to reduce the outward heat radiation; a plurality of stainless steel grids 502 are arranged inside the frame 501, and each stainless steel grid 502 is distributed in an "S" shape inside the frame 501; it is convenient for the internal cooling water to flow smoothly in an "S" shape, and the water with too high temperature will not accumulate, so as to achieve the purpose of uniformly cooling the side and bottom of the rock sample 1; the present application only heats the upper surface of the rock sample 1, and cools the surrounding and bottom of the rock sample 1, which is more in line with the actual construction situation, improves the accuracy of the experimental results, can more realistically simulate the TBM rock breaking process, and simulates the actual heating situation of the face during the excavation process, which is helpful for scientific researchers to have a deeper understanding of the TBM rock breaking mechanism, and provides theoretical support for optimizing excavation parameters and improving excavation efficiency.

[0052] A water inlet 503 and a water outlet 504 are provided at the bottom of the frame 501, and the water inlet 503 and the water outlet 504 are both connected to the inner cavity of the working platform 2; a water inlet channel 202 and a water outlet channel 203 are provided inside the working platform 2, the water inlet channel 202 is connected to the water inlet 503 of the frame 501, and the water outlet channel 203 is connected to the water outlet 504 of the frame 501; the water inlet channel 202 is connected to a water inlet pipe, the water outlet channel 203 is connected to a drain pipe, the water inlet pipe is connected to a water tank, and a metering pump 201 is provided on the water inlet pipe, and the metering pump 201 is used to accurately measure water pressure and flow rate.

[0053] The mechanized heat-insulating housing includes a housing 101, a housing 2 102 and an upper cover plate. In one embodiment, Figure 8As shown, both sides of the shell 101 and the shell 2 102 are connected with mechanical arms 103, and the two mechanical arms 103 are connected with the control motor 104 through a first screw connection. Specifically, the output shaft of the control motor 104 is connected with a single-head screw 1032, and the single-head screw 1032 is threadedly connected to the mechanical arm 103, and the control motor 104 is fixed to the bottom of the gantry frame 3 by bolts; the two control motors 104 are used to drive the corresponding two mechanical arms 103 to move closer to or away from each other; the upper cover plate can be opened and closed above the shell 101 and the shell 2 102, and when the upper cover plate is covered on the shell 101 and the shell 2 102, a closed cavity is formed.

[0054] In a possible implementation, Fig. 9 As shown, both sides of the housing 101 and the housing 2 102 are connected with a mechanical arm 103, and the two mechanical arms 103 are installed on the second screw 1031, and the second screw 1031 is a double-headed screw, and the rotation directions of the two ends are opposite. The two mechanical arms 103 are threadedly connected to the second screw 1031. In this embodiment, the number of control motors 104 is one, and the number of second screws 1031 is also one. This embodiment successfully simplifies the synchronous movement of the two mechanical arms 103 into the drive of a control motor 104 by using a double-headed screw as the second screw 1031 and making the rotation directions of its two ends opposite, thereby reducing the complexity and cost of the system. Secondly, this design enhances the stability of the structure, because the two mechanical arms 103 are connected by a common second screw 1031, so that their movements are more coordinated. In general, this embodiment optimizes the system structure while maintaining functionality, and improves stability and economy.

[0055] Alumina felt and ceramic liner are arranged inside the shell 101 and the shell 2 102, and a heat insulation sealing strip is arranged at the connection between the shell 101 and the shell 2 102, wherein the intersecting parts of the shell 101 and the shell 2 102 are arranged in a tooth-like distribution, so that the shell 101 and the shell 2 102 can be closed tightly, wherein the material of the shell 101 and the shell 2 102 is high temperature resistant stainless steel material, and ceramic fiber polycrystalline mullite plate 7 is arranged inside the shell 101 and the shell 2 102 to prevent heat dissipation.

[0056] The heating module and the cooling module are installed at the upper cover plate position of the mechanized heat-insulating shell. The heating module and the cooling module are alternately arranged. By adopting the alternating arrangement, when performing cyclic heating and cooling, the temperature change of the rock sample 1 during the TBM rock breaking process can be more accurately simulated, so as to further study the thermophysical properties and rock breaking mechanism of the rock sample 1; and the heating module and the cooling module are connected with a central control panel 8, and the central control panel 8 is used to control the heating module and the cooling module. The heating module includes a resistance chamber 106 and a heating resistance rod 105. The resistance chamber 106 is made of high-temperature resistant stainless steel material, and the heating resistance rod 105 is arranged at Inside the resistor compartment 106, the top of the resistor compartment 106 is connected to the high temperature resistant telescopic rod 107; the top of the high temperature resistant telescopic rod 107 is connected to the upper cover plate, and the high temperature resistant telescopic rod 107 is divided into two sections to facilitate surface heating and linear heating of the rock sample 1. When the high temperature resistant telescopic rod 107 is extended by one section, the resistor compartment 106 is located above the rock sample 1, and the resistor compartment 106 does not contact the rock sample 1, which is convenient for surface heating of the rock sample 1; when the high temperature resistant telescopic rod 107 is extended by two sections, the bottom of the resistor compartment 106 abuts against the upper surface of the rock sample 1, and the resistor compartment 106 abuts against the rock sample 1, simulating linear heating of the rock sample 1.

[0057] The cooling module includes a delivery pipe 108 and a coolant nozzle 109. The delivery pipe 108 is placed inside the mechanized heat-insulating shell. The working platform 2 is provided with a coolant channel 204. The delivery pipe 108 is connected to the coolant channel 204 of the working platform 2. The coolant channel 204 is connected to a metering pump, which is connected to a coolant tank. The coolant tank is divided into two compartments, which are respectively filled with water and liquid nitrogen. The coolant nozzle 109 is suspended on the upper cover plate through a high-temperature resistant telescopic rod 107. The upper cover plate is provided with an infrared thermometer 9. The number of infrared thermometers 9 is five. The high-temperature resistant telescopic rod 107 An electric motor 112 is installed on the upper cover, and a built-in slide rail 110 is provided on the upper cover. The electric motor 112 is installed on the built-in slide rail 110. When the electric motor 112 is started, the electric motor 112 can move on the built-in slide rail 110. More specifically, the high temperature resistant telescopic rod 107 installed on the electric motor 112 is pushed. The electric motor 112 moves and pushes the high temperature resistant telescopic rod 107 to move in the built-in slide rail 110. The high temperature resistant telescopic rod 107 can be extended and moved, and the coolant nozzle 109 can be freely moved in the horizontal and vertical directions, and precise regional spray cooling can be achieved;

[0058] It should be noted that the movement of the electric motor 112 on the built-in slide rail 110 is a conventional technology, and the specific structure is not described in this application.

[0059] The coolant nozzle 109 includes a liquid nitrogen nozzle 1091, a rotating arm 1092, a water nozzle 1093, a threaded flexible joint 1094 and a self-operated temperature regulating valve 1095. The delivery pipe 108 is connected to the coolant nozzle 109 through the threaded flexible joint 1094. The rotating arm 1092 contains a temperature sensor. A plurality of water nozzles 1093 are arranged outside the rotating arm 1092. The water nozzles 1093 are arranged unevenly. The unevenly distributed water nozzles 1093 of the coolant nozzle 109 drive the rotating arm 1092 to rotate through the reaction of the water flow to achieve irregular spraying, which can cool the surface of the rock sample 1 more evenly and improve the cooling efficiency. At the same time, this design enhances the fluidity of the coolant, avoids cooling dead corners, and ensures the accuracy of the experimental results and the long-term stable operation of the equipment.

[0060] A sleeve 1096 is sleeved on the rotating arm 1092, and the sleeve 1096 can be moved and adjusted on the rotating arm 1092 to open or close the water nozzle 1093, which is convenient for control and use during simulation tests.

[0061] The loading module includes a hydraulic cylinder 401 fixedly installed on the gantry frame 3, the hydraulic cylinder 401 is located in the middle of the gantry frame 3, the piston end of the hydraulic cylinder 401 is connected to a movable crossbeam 402, a movable guide rail 405 is arranged between the movable crossbeam 402 and the gantry frame 3, the movable crossbeam 402 and the gantry frame 3 are slidably connected through the movable guide rail 405, and a sensor mounting frame 407 is arranged at the lower part of the movable crossbeam 402; a three-axis force sensor 406 is arranged at the lower part of the sensor mounting frame 407, and the three-axis force sensor 406 is used to measure the vertical force, tangential force and lateral force exerted on the disc-type roller 404; the three-axis force sensor 406 is connected to a cutter seat 403, a disc-type roller 404 is arranged on the cutter seat 403, and the three-axis force sensor 406 is used to monitor the force condition of the disc-shaped roller. When the loading module is started, the hydraulic cylinder 401 pushes the movable crossbeam 402 to move vertically on the movable guide rail 405, driving the disc cutter 404 to penetrate the rock sample 1 downward at a fixed speed to perform a simulated cutting test of the rock sample 1.

[0062] A base 302 is provided on the gantry frame 3 , and a brake module 6 is installed at the bottom of the working platform 2 , and the brake module 6 is provided on the base 302 .

[0063] The brake module 6 includes a horizontal support 605 arranged on the base 302, and a mounting gear 603 is arranged on the horizontal support 605. A gear guide rail 604 and a servo motor 601 are arranged inside the base 302. The number of servo motors 601 is one, which is embedded in the middle of the base 302, and the gear guide rail 604 is meshed with the mounting gear 603. The base 302 is rotatably connected with a threaded guide 602, which is threadedly connected to the working platform 2, and the threaded guide rail 602 is connected to the servo motor 601. The servo motor 601 drives the threaded guide rail 602 to rotate, thereby driving the working platform 2 to move. By setting the gear guide rail 604 to mesh with the mounting gear 603, it is convenient to maintain the stable movement of the working platform 2 in the horizontal direction. At the same time, starting the loading module can realize the horizontal linear cutting of the upper surface of the rock sample 1 by the disc-type roller 404.

[0064] On the other hand, the present invention also proposes a method for simulating high and low temperature cycle rock breaking test of a tunnel face, using the aforementioned simulated tunnel face high and low temperature cycle rock breaking test platform, comprising the following steps:

[0065] S1: Place the prepared rock sample 1 into the insulation device 5, start the two control motors 104, and drive the corresponding mechanical arms 103 to work, so that the shell 1 101 and the shell 2 102 are close to each other, and at the same time close the upper cover plate to make the mechanized insulation shell completely closed; the rock sample 1 is located in the mechanized insulation shell.

[0066] S2: Connect the water inlet channel 202 on the working platform 2 to the external water supply source, connect the water outlet channel 203 to the external drainage pipe, and connect the coolant channel 204 to the external coolant tank; the coolant tank is divided into two compartments, respectively filled with water and liquid nitrogen.

[0067] S3: Input the target temperature on the central console, select surface heating or line heating according to the test requirements, control the high temperature resistant telescopic rod 107 and the heating resistor rod 105, and monitor the temperature of each position of the rock sample 1 in real time according to the feedback of the infrared thermometer 9;

[0068] For example, in a line heating test, the high-temperature resistant telescopic rod 107 on the resistance chamber 106 at the required specific position is controlled to extend downward in two sections until it touches the upper surface of the rock sample 1 and then stops extending, so as to precisely heat the required heating part of the rock sample 1 in close proximity; the temperature conditions of various positions of the rock sample 1 are displayed on the central console through feedback from the infrared thermometers 9 arranged at the four corners and the middle of the upper part of the mechanized heat-insulating shell.

[0069] S4: Turn on the heat insulation device 5, turn on the metering pump 201, calculate and input the corresponding water flow rate according to the target temperature, and let the water enter the heat insulation device 5 at a certain flow rate.

[0070] S5: After the central console displays that the preset temperature has been reached, the heating resistor 105 is turned off, the cooling module is started, and surface cooling or line cooling is selected according to the test requirements to achieve accurate cooling of the rock sample 1;

[0071] After the central console displays that the target temperature has been reached, the heating resistor rod 105 is turned off, the high temperature resistant telescopic rod 107 is controlled to retract, and the resistor compartment 106 is brought back to the upper part of the mechanized heat insulation shell; the metering pump is turned off and the coolant channel 204 is connected.

[0072] If surface cooling is performed, the high temperature resistant telescopic rods 107 on all the coolant nozzles 109 are controlled to extend a section, so that all the coolant nozzles 109 are lowered, and the metering pump 201 is started to pump the water in the coolant tank into the coolant channel 204, and the water nozzle 1093 on the rotating arm 1092 sprays liquid, and at the same time the rotating arm 1092 starts to rotate, and the electric motor 112 on the high temperature telescopic rod is started to push the coolant nozzle 109 to move slowly back and forth, so that the cooling water is evenly spread on the upper surface of the rock sample 1;

[0073] For example, when line cooling is performed, the high temperature resistant telescopic rod 107 on the coolant nozzle 109 next to the resistance chamber 106 used for corresponding line heating is controlled to be lowered by two sections, the coolant nozzle 109 is close to the surface of the rock sample 1, the metering pump is turned on, and the cooling liquid nitrogen is pumped into the delivery pipeline 108. At the same time, the electric motor 112 on the high temperature telescopic rod is started to push the coolant nozzle 109 to move back and forth on the built-in guide rail, and the cooling liquid nitrogen is directly ejected from the liquid nitrogen nozzle 1091 to achieve precise line cooling.

[0074] S6: After the central console reaches room temperature, the mechanical arm 103 is started to open the mechanized heat-insulating housing, exposing the rock sample 1 and placing the rock sample 1 under the loading module;

[0075] After the display on the central console 8 shows that the temperature inside the mechanized heat-insulating shell reaches room temperature, the motor base 302 is started to drive the mechanical arm 103 to separate the right mechanized heat-insulating shell and the left mechanized heat-insulating shell to expose the upper surface of the rock sample 1 below the loading module.

[0076] S7: Start the loading module, the hydraulic cylinder 401 pushes the movable crossbeam 402, driving the disc cutter 404 to move downward at a constant rate, and at the same time start the brake module 6 installed at the bottom of the working platform 2 to drive the working platform 2 to start moving, realize the rolling of the cutter to break the rock, and obtain the three-dimensional force state of the disc cutter 404.

[0077] Specifically, the hydraulic cylinder 401 located on the upper part of the gantry frame 3 is opened to push the movable crossbeam 402 to move vertically downward. The movable crossbeam 402 is connected to the cutter seat 403, driving the disc-type roller cutter 404 to move vertically downward at a constant rate to invade the rock sample 1; at the same time, the brake module 6 installed at the bottom of the working platform 2 is opened, and the servo motor 601 is started to drive the threaded guide 602 to rotate, and the gear also moves on the gear guide rail 604, pushing the working platform 2 to move in the horizontal direction to achieve the roller cutter rolling and breaking the rock; the three-dimensional force state of the disc-type roller cutter 404 is obtained through the three-dimensional force sensor 406 connected to the upper part of the cutter seat 403, and the influence of high and low temperature cycles on the rock breaking efficiency is studied.

[0078] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or change made by a person skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A high and low temperature cycle rock breaking test platform simulating a tunnel face, characterized in that: include: A working platform (2), a gantry frame (3) and a loading module, wherein the working platform (2) is arranged at the bottom of the gantry frame (3) and is used to carry the rock sample (1); and the loading module is installed above the gantry frame (3) and is used to perform rock breaking simulation on the rock sample; A heat insulating device (5) is arranged on the upper part of the working platform (2), the heat insulating device (5) comprising a frame (501) with a hollow structure, a cooling flow channel being formed in the frame (501) for heat insulating the side and bottom surfaces of the rock sample (1); It also includes a mechanized heat-insulating shell covering the outer periphery of the heat-insulating device (5) and a temperature control unit arranged on the mechanized heat-insulating shell, wherein the number of the temperature control units is multiple; The temperature control unit comprises a high temperature resistant telescopic rod (107), a heating module and a cooling module, the high temperature resistant telescopic rod (107) being connected to the heating module and the cooling module respectively, and the high temperature resistant telescopic rod (107) being capable of driving the heating module and the cooling module to approach or move away from the surface of the rock sample (1); The thermal insulation device (5) further comprises a ceramic fiber polycrystalline mullite plate, wherein the ceramic fiber polycrystalline mullite plate is attached to the outside and / or inside of the frame (501); A plurality of stainless steel grids (502) are arranged inside the frame (501), and each of the stainless steel grids (502) is distributed in an "S" shape inside the frame (501); A water inlet (503) and a water outlet (504) are provided at the bottom of the frame (501), and both the water inlet (503) and the water outlet (504) are in communication with the inner cavity of the working platform (2); A water inlet channel (202) and a water outlet channel (203) are provided inside the working platform (2); the water inlet channel (202) is connected to the water inlet of the frame (501), and the water outlet channel (203) is connected to the water outlet of the frame (501); The water inlet channel (202) is connected to a water inlet pipe, the water inlet pipe is connected to a water tank, and an application metering pump (201) is provided on the water inlet pipe; A base (302) is provided on the gantry frame (3), a brake module (6) is installed at the bottom of the working platform (2), and the brake module (6) is arranged on the base (302); The braking module (6) comprises a horizontal support (605) arranged on a base (302), a mounting gear (603) being arranged on the horizontal support (605), a gear guide rail (604) and a servo motor (601) being arranged inside the base (302), the gear guide rail (604) being meshed with the mounting gear (603); a threaded conduit (602) being rotatably connected to the base (302), the threaded conduit (602) being threadedly connected to the working platform (2), and the threaded conduit (602) being connected to the servo motor (601); The mechanized heat-insulating housing comprises a housing 1 (101), a housing 2 (102) and an upper cover plate, both sides of the housing 1 (101) and the housing 2 (102) are connected to mechanical arms (103), and both the mechanical arms (103) are provided with control motors (104); The two control motors (104) are used to respectively drive the corresponding two mechanical arms (103) to move closer to or farther from each other; Alumina felt and a ceramic liner are provided inside the shell 1 (101) and the shell 2 (102), and a heat insulation sealing strip is provided at the connection between the shell 1 (101) and the shell 2 (102); The loading module comprises a hydraulic cylinder (401) fixedly mounted on the gantry frame (3), the hydraulic cylinder (401) being located in the middle of the gantry frame (3), a piston end of the hydraulic cylinder (401) being connected to a movable crossbeam (402), a movable guide rail (405) being arranged between the movable crossbeam (402) and the gantry frame (3), the movable crossbeam (402) and the gantry frame (3) being connected via the movable guide rail (405), a sensor mounting frame (407) being arranged at the lower part of the movable crossbeam (402); a three-axis force sensor (406) being arranged at the lower part of the sensor mounting frame (407), a knife seat (403) being connected to the three-axis force sensor (406), a disc-shaped hob (404) being arranged on the knife seat (403), the three-axis force sensor (406) being used to monitor the force condition of the disc-shaped hob (404); The heating modules and the cooling modules are arranged alternately; The heating module comprises a resistance chamber (106) and a heating resistance rod (105); the heating resistance rod (105) is arranged inside the resistance chamber (106); the top of the resistance chamber (106) is connected to a high temperature resistant telescopic rod (107); the top of the high temperature resistant telescopic rod (107) is connected to an upper cover plate; the high temperature resistant telescopic rod (107) is divided into two sections to facilitate surface heating and linear heating of the rock sample (1); when the high temperature resistant telescopic rod (107) is extended by one section, the resistance chamber (106) is located above the rock sample (1), the resistance chamber (106) and the rock sample (1) are not in contact, and surface heating of the rock sample (1) is facilitated; when the high temperature resistant telescopic rod (107) is extended by two sections, the bottom of the resistance chamber (106) abuts against the upper surface of the rock sample (1), the resistance chamber (106) abuts against the rock sample (1), and the linear heating of the rock sample (1) is simulated; The cooling module comprises a delivery pipeline (108) and a cooling liquid nozzle (109); the cooling liquid nozzle (109) is suspended on the upper cover plate via a high temperature resistant telescopic rod (107); the upper cover plate is provided with an infrared thermometer (9); the high temperature resistant telescopic rod (107) is provided with an electric motor (112); the upper cover plate is provided with a built-in slide rail (110); and the electric motor (112) is installed on the built-in slide rail (110); The coolant nozzle (109) comprises a liquid nitrogen nozzle (1091), a rotating arm (1092), a water nozzle (1093), a threaded flexible joint (1094) and a self-operated temperature regulating valve (1095); the delivery pipeline (108) is connected to the coolant nozzle (109) via the threaded flexible joint (1094); a temperature sensor is contained in the rotating arm (1092); a plurality of water nozzles (1093) are arranged outside the rotating arm (1092); and the water nozzles (1093) are arranged in an uneven distribution.

2. The simulated tunnel face high and low temperature cycle rock breaking test platform according to claim 1 is characterized by: The rotating arm (1092) is sleeved with a sleeve (1096), and the sleeve (1096) can move on the rotating arm (1092) to open or close the water nozzle (1093).

3. A method for simulating high and low temperature cycle rock breaking test of a tunnel face, using the simulated tunnel face high and low temperature cycle rock breaking test platform according to any one of claims 1-2, characterized in that: The following steps are involved: S1: placing the prepared rock sample (1) into the heat-insulating device (5), and starting the mechanical arm (103) to completely close the mechanized heat-insulating housing; S2: connecting the water inlet channel (202) on the working platform (2) to a water source, connecting the water outlet channel (203) to a drain pipe, and connecting the coolant channel (204) to a coolant tank; S3: Input the target temperature on the central control console (8), select surface heating or line heating according to the test requirements, control the high temperature resistant telescopic rod (107) and the heating resistor rod (105), and monitor the temperature of each position of the rock sample (1) in real time according to the feedback from the infrared thermometer (9); S4: turning on the heat insulation device (5), calculating and inputting a corresponding water flow rate according to the target temperature, and allowing the water to enter the heat insulation device (5) at a preset flow rate; S5: When the central control console (8) displays that the preset temperature has been reached, the heating resistor (105) is turned off, and the cooling module is started. Surface cooling or line cooling is selected according to the test requirements to achieve accurate cooling of the rock sample (1); S6: After the central console (8) reaches room temperature, the mechanical arm (103) is started to open the mechanized heat-insulating housing, exposing the rock sample (1) and placing the rock sample (1) below the loading module; S7: The loading module is started, and the hydraulic cylinder (401) pushes the movable crossbeam (402), driving the disc cutter (404) to move downward at a constant speed. At the same time, the brake module (6) at the bottom of the working platform (2) is started, driving the working platform (2) to start moving, so as to achieve rock breaking by the cutter, and obtain the three-dimensional force state of the disc cutter (404).

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