CN218098679U - Experimental device for large-size true triaxial coal-rock mass multi-field seepage coupling system - Google Patents

Abstract

The utility model discloses a true triaxial coal rock mass multi-field seepage coupled system experimental apparatus of jumbo size relates to mining engineering test device technical field. The utility model comprises a triaxial loading system, a seepage sealing system, a back pressure system, a data acquisition and analysis system and a triaxial loading chamber, wherein the seepage system comprises a liquid injection seepage system and a gas injection seepage system; the triaxial loading chamber comprises a triaxial loading chamber steel frame. The utility model adopts servo control, and has the advantages of high precision, strong controllability, small error and the like; the utility model adopts the soft and elastic rubber sleeve to seal the edge, and has the advantages of good sealing effect, convenient operation, easy control and the like; the utility model discloses have advantages such as the degree of freedom is high, maneuverability is strong and on the seepage flow medium in the selection of seepage flow direction, not only can carry out the seepage flow test to liquid, can also carry out the seepage flow test to gas, have advantages such as use extensively, wide coverage.

Description

Experimental device for large-size true triaxial coal-rock mass multi-field seepage coupling system

Technical Field

The utility model belongs to the technical field of mining engineering test device, especially, relate to true triaxial coal rock mass multi-field seepage coupled system experimental apparatus of jumbo size.

Background

Seepage occurs in construction of numerous projects, at the present stage, the construction of large-scale capital construction projects in China still lasts for a period of time, the construction of underground projects is more key for the next development, the transfer rule of liquid and gas in rock-soil bodies is made clear, the necessary way for solving a series of problems including water diversion crack disaster and underground project seepage prevention is solved, and laboratory tests are scientific, reasonable and economic means but need the support of experimental equipment.

The patent application with the publication number of CN112903470A discloses a high-temperature seepage coupling experimental device and a high-temperature seepage coupling experimental method based on a hard rock true triaxial system, wherein the device comprises an insulation can, a heating pipeline, a cooling pipeline and a seepage type mutual buckling clamp; placing a rock sample in the heat preservation box; vertical loading holes are symmetrically formed in the upper side wall and the lower side wall of the heat preservation box, and horizontal loading holes are symmetrically formed in the left side wall and the right side wall of the heat preservation box; the rock sample is packaged by a seepage type mutual buckling clamp, and an LVDT displacement sensor group for measuring the deformation of the rock sample is installed on the seepage type mutual buckling clamp; the heating pipeline is arranged on the inner surface of the insulation box body opposite to the confining pressure loading surface of the rock sample; the cooling pipeline is arranged at the outer sides of the vertical loading hole and the horizontal loading hole of the incubator. The experimental method comprises the following steps: installing the experimental device into true triaxial loading equipment, preparing a sample combination body and sending the sample combination body into a heat insulation box; accurately centering and clamping the sample assembly and filling hydraulic oil; starting heating and cooling; starting seepage loading; and starting true triaxial loading and finishing seepage measurement.

At present, the seepage experiment equipment aiming at China is mostly small experiment equipment aiming at small coal rock samples, the size of rocks has obvious influence on the strength and other properties of the rocks, smaller experiment samples have obvious limitation on reflecting field working conditions, true triaxial seepage experiment equipment has less mention, triaxial can not independently load servo control, aiming at a sealing mode, most of the existing seepage experiment equipment adopts false triaxial to seal through oil pressure, the defects of poor sealing effect, easy channeling of sealing liquid and seepage media and the like are overcome, and due to the secret property and invisibility of underground seepage activity, the existing seepage experiment equipment mostly adopts sensors such as flow, velocity and pressure and the like to detect the seepage process in the liquid migration condition in the seepage process, and the defects of invisibility, hysteresis and blindness are overcome.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a true triaxial coal rock mass multi-site seepage flow coupled system experimental apparatus of jumbo size, it is relatively poor to have solved the sealed effect of seepage flow experimental facilities among the prior art, and has the technical problem of invisibility, hysteresis quality and blindness nature shortcoming.

In order to achieve the purpose, the utility model is realized by the following technical proposal:

the large-size true triaxial multi-field seepage coupling system experimental device for the coal rock mass comprises a triaxial loading system, a seepage sealing system, a back pressure system, a data acquisition and analysis system and a triaxial loading chamber, wherein the seepage system comprises a liquid injection seepage system and a gas injection seepage system;

the triaxial loading room includes triaxial loading room steelframe, installs gum cover on the triaxial loading room steelframe, installs a plurality of bearing plates on the triaxial loading room steelframe, the connecting hole has been seted up on the bearing plate, the seepage flow system the back pressure system all with the connecting hole is connected.

Optionally, the triaxial loading room steel frame is a square frame, the triaxial loading room steel frame is provided with a plurality of placing grooves, and the bearing plates correspond to the placing grooves one to one.

Optionally, the three-axis loading system includes: the loading device comprises an X-axis servo loading system, a Y-axis servo loading system and a Z-axis servo loading system which are connected with a bearing plate, wherein a first sensor, a second sensor and a third sensor are respectively arranged on the X-axis servo loading system, the Y-axis servo loading system and the Z-axis servo loading system, and an axial loading oil cylinder is arranged on the outer side of the bearing plate.

Optionally, the seepage sealing system mainly includes: the system comprises a first liquid storage container, a confining pressure tracking pump connected with the first liquid storage container, a first switch valve connected with the confining pressure tracking pump, and a fourth sensor connected with the first switch valve, wherein the first switch valve corresponds to a rubber sleeve, and a sensor in the confining pressure tracking pump is arranged in the confining pressure tracking pump.

Optionally, the back pressure system mainly includes: the pressure-return pump comprises a second liquid storage container, a pressure-return pump connected with the second liquid storage container, a second switch valve connected with the pressure-return pump, a pressure-return buffer container connected with the second switch valve, a fifth sensor connected with the pressure-return buffer container, and a pressure-return valve connected with the fifth sensor, wherein a sensor in the pressure-return pump is arranged in the pressure-return pump, and the fifth sensor corresponds to the pressure-bearing plate.

Optionally, the data acquisition system mainly includes: the pressure bearing plate comprises a plurality of ultrasonic probes arranged in the pressure bearing plate, a plurality of ultrasonic transmitting and receiving devices connected with the ultrasonic probes, a wireless router connected with the ultrasonic transmitting and receiving devices, an operating system wirelessly connected with the wireless router, and a data storage center wirelessly connected with the wireless router.

Optionally, the liquid injection percolation system comprises: third stock solution container, with the precision injection pump that third stock solution container is connected, with the precision injection pump with the first solenoid valve that the back-pressure valve is connected, with the sixth sensor that first solenoid valve is connected, with the third ooff valve that the pressure-bearing plate is connected, with vapour and liquid separator that the back-pressure valve is connected, install wet flowmeter on vapour and liquid separator, with the electronic balance that vapour and liquid separator is connected is equipped with the interior sensor of precision injection pump in the precision injection pump.

Optionally, the gas injection system comprises: the gas cylinder, a fourth switch valve connected with the gas cylinder, a gas compression pump connected with the fourth switch valve, a second electromagnetic valve connected with the gas compression pump, a fifth switch valve connected with the gas compression pump, a buffer container connected with the fifth switch valve, a sixth switch valve connected with the buffer container, a seventh sensor connected with the sixth switch valve, a third electromagnetic valve connected with the pressure bearing plate and a pressure regulating valve connected with the third electromagnetic valve.

Optionally, the experimental method of the seepage system includes the following steps:

s1, manufacturing a seepage test piece by using a large-size mold according to a specified ratio, demolding by using a demolding tool after the seepage test piece is solidified, and repairing the place with damaged edge by using epoxy resin glue to ensure that a seepage sealing system can effectively seal the test piece;

and S2, placing the test piece into a cubic cavity of the triaxial loading chamber, and fixing the open movable surface on the triaxial loading chamber by using a high-strength bolt to form an externally sealed whole. Setting the three-axis axial pressure to reach the simulated axial pressure;

s3, filling water into the first liquid storage container, opening a first switch valve, setting confining pressure, starting a confining pressure tracking pump to inject water into the rubber sleeve, stopping the confining pressure tracking pump when preset pressure is reached, and closing the first switch valve;

s4, opening a third electromagnetic valve or a first electromagnetic valve of the seepage system and a data acquisition and analysis system; opening the back pressure system, opening a third switch valve, and connecting the cavity with the atmosphere;

s5, respectively utilizing a gas injection system and a liquid injection system in the seepage system to perform a seepage experiment on the coal rock, wherein when the gas seepage experiment is performed, firstly, the gas in the gas cylinder is observed, whether the pressure reaches a set pressure or not is observed, and the operation of electrifying and supplementing the pressure is not required;

s6, after the experiment is finished, closing the seepage system, the back pressure system and the triaxial loading system, and closing the data acquisition and analysis system under the condition of determining data storage;

and S7, discharging the pressurized water in the rubber sleeve, then detaching the high-strength bolt with the opened moving surface, and unloading the test piece.

The embodiment of the utility model has the following beneficial effect:

the utility model provides an embodiment which is more suitable for the actual experimental device of the engineering aiming at the large-size coal rock mass; the utility model adopts servo control, and has the advantages of high precision, strong controllability, small error and the like; the utility model adopts the soft and elastic rubber sleeve to seal the edge, and has the advantages of good sealing effect, convenient operation, easy control and the like; the utility model has the advantages of high degree of freedom, strong operability and the like in the selection of seepage direction, can not only carry out seepage test on liquid, but also carry out seepage test on gas on seepage medium, and has the advantages of wide application, wide coverage and the like; the utility model adopts ultrasonic wave to detect the seepage condition of liquid in the seepage process aiming at the detection mode, and has the advantages of accuracy, intuition and science; meanwhile, the data acquisition and analysis system is matched, so that the whole device has the advantages of higher accuracy, high automation degree, complete system, complete functions, simplicity in operation and the like.

Drawings

The accompanying drawings, which form a part of the present application, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a layout diagram of the overall structure of the present invention;

FIG. 2 is an acoustic emission array layout;

FIG. 3 is a schematic view of the location of the apertures of the pressure bearing plate;

FIG. 4 is a schematic view of an arrangement of acoustic emission arrays in a hollow pressure plate;

FIG. 5 is a schematic diagram of a gum cover arrangement;

FIG. 6 is an enlarged view of a portion of the gum cover arrangement;

fig. 7 is a schematic view of a first end portion according to an embodiment of the present invention;

FIG. 8 is a schematic view of the structure at A in FIG. 7;

fig. 9 is a schematic structural view of a first baffle according to an embodiment of the present invention;

fig. 10 is a schematic view of a second end portion according to an embodiment of the present invention;

fig. 11 is a schematic cross-sectional view of a second end portion according to an embodiment of the present invention.

Wherein the figures include the following reference numerals:

an X-axis servo loading system 1, a Y-axis servo loading system 2, a Z-axis servo loading system 3, a first sensor 4, a second sensor 5, a third sensor 6, a gas cylinder 7, a fourth switch valve 8, a second electromagnetic valve 9, a pressure gauge 10, a gas compression pump 11, a fifth switch valve 12, a buffer container 13, a sixth switch valve 14, a seventh sensor 15, a pressure regulating valve 16, a third electromagnetic valve 17, a third liquid storage container 18, a precision injection pump 19, a precision injection pump in-pump sensor 20, a first electromagnetic valve 21, a sixth sensor 22, a first liquid storage container 23, a confining pressure tracking pump 24, a confining pressure tracking pump in-pump sensor 25, a first switch valve 26, a fourth sensor 27, a rubber sleeve 28, a pressure bearing plate 29, a pressure bearing cover plate 30, a high-strength bolt 31, a second liquid storage container 32, a return pressure pump 33, the device comprises a back-pressure pump internal sensor 34, a second switch valve 35, a back-pressure buffer container 36, a fifth sensor 37, a back-pressure valve 38, a gas-liquid separator 39, a wet sensor 40, a third switch valve 41, a water collection container 42, an electronic balance 43, an ultrasonic probe 44, an ultrasonic wave transmitting and receiving device 45, a wireless router 46, an operating system 47, a data storage center 48, a three-axis loading chamber 49, an ultrasonic wave transmitting end 50, an ultrasonic wave receiving end 51, a connecting hole 52, an ultrasonic probe signal wire 53, a three-axis loading chamber steel frame 54, a pressure-bearing pipe 60, a connecting assembly 61, a first end 62, a second end 63, a first baffle plate 64, a notch 65, a push block 66, a sleeve 67, a second baffle plate 68, a collar 69, a limiting hole 70, a first passing groove 71, a second passing groove 72, a limiting groove 73, a notch 75, a stop 76 and a push rod 77.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

To keep the following description of the embodiments of the present invention clear and concise, a detailed description of known functions and known parts of the invention has been omitted.

Example 1: referring to fig. 1-6, in the present embodiment, a large-size true triaxial coal-rock mass multi-field seepage coupling system experimental apparatus is provided, which includes a triaxial loading system, a seepage sealing system, a back pressure system, a data acquisition and analysis system, and a triaxial loading chamber, where the seepage system includes a liquid injection seepage system and a gas injection seepage system; the triaxial loading system mainly provides axial pressure by the X-axis servo loading system 1, the Y-axis servo loading system 2 and the Z-axis servo loading system 3, and acts on a test piece in the cavity through the bearing plates 29 corresponding to all the surfaces to provide confining pressure for the test piece, simulate formation pressure or provide pressure for fracturing of the test piece;

the triaxial loading chamber 49 comprises a triaxial loading chamber steel frame 54, a rubber sleeve 28 arranged on the triaxial loading chamber steel frame 54 and a plurality of pressure-bearing plates 29 arranged on the triaxial loading chamber steel frame 54, wherein the pressure-bearing plates 29 are provided with connecting holes 52, and the seepage system and the back pressure system are connected with the connecting holes 52; the seepage system is mainly divided into a liquid seepage system and a gas seepage system, wherein the rubber sleeve 28 can be a fluorine rubber sleeve.

The liquid seepage system operates as follows: seepage fluid is stored in a third liquid storage container 18 and is connected to a seepage injection surface through a pipeline by a precision injection pump 19, wherein a first electromagnetic valve 21 is used for controlling the pressure of input fluid, a sixth sensor 22 is used for detecting the pressure of the actual inflow fluid, then the liquid with pressure flows into the seepage injection surface of the test piece through a seepage injection surface interface and a central connecting hole 52 of the pressure bearing plate 29, and the liquid with pressure seeps through the test piece. Flows out through the central connecting hole 52 of the opposite pressure bearing plate, stably flows to the gas-liquid separator 39 through the third switch valve 41 and the back pressure valve 38, is separated, and then flows into the water collecting container 42 for collection and weighing.

It should be noted that all the electric devices referred to in this application may be powered by a storage battery or an external power source.

The utility model provides a large-scale true triaxial coal rock mass seepage coupling test system, which is more suitable for engineering practical experimental devices; the servo control is adopted, so that the method has the advantages of high precision, strong controllability, small error and the like; the edge sealing is carried out by adopting the soft and elastic rubber sleeve 28, and the sealing device has the advantages of good sealing effect, convenience in operation, easiness in control and the like; the method has the advantages of high degree of freedom, strong operability and the like in the aspect of selecting the seepage direction; on the seepage medium, not only can carry out seepage test on liquid, but also can carry out seepage test on gas, and has the advantages of wide application, wide coverage and the like; aiming at the detection mode, the ultrasonic wave is adopted to detect the seepage condition of the liquid in the seepage process, and the method has the advantages of accuracy, intuition and science; meanwhile, the data acquisition and analysis system is matched, so that the whole device has the advantages of higher accuracy, high automation degree, complete system, complete functions, simplicity in operation and the like.

The triaxial loading chamber steel frame 54 of the present embodiment is a square frame, and the triaxial loading chamber steel frame 54 is provided with a plurality of placing grooves, and the pressure-bearing plates 29 are placed in one-to-one correspondence with the placing grooves. The triaxial loading system includes: the X-axis servo loading system 1, the Y-axis servo loading system 2 and the Z-axis servo loading system 3 are connected with the bearing plate 29, the X-axis servo loading system 1, the Y-axis servo loading system 2 and the Z-axis servo loading system 3 are respectively provided with a first sensor 4, a second sensor 5 and a third sensor 6, and the outer side of the bearing plate 29 is provided with an axial loading oil cylinder. The triaxial loading chamber 49 is internally provided with a cubic space, six sides of the triaxial loading chamber are provided with pressure bearing plates 29 with spaces inside, twelve ridges are uniformly distributed with rubber sleeves 28, the pressure bearing plates 29 are fixed by positioning grooves distributed in the triaxial loading chamber 49, the centers of the pressure bearing plates 29 are provided with round small holes, connecting pipelines are connected with the pressure bearing plates 29 through connecting holes 52, and the outer sides of the pressure bearing plates 29 are provided with axial loading oil cylinders.

The triaxial loading system mainly provides axial pressure by the X-axis servo loading system (1), the Y-axis servo loading system (2) and the Z-axis servo loading system (3), and acts on a test piece in the cavity through the pressure bearing plates (29) corresponding to all surfaces to provide confining pressure for the test piece, simulate formation pressure or provide pressure for fracturing of the test piece.

The seepage sealing system of this embodiment mainly includes: the device comprises a first liquid storage container 23, a confining pressure tracking pump 24 connected with the first liquid storage container 23, a first switch valve 26 connected with the confining pressure tracking pump 24, and a fourth sensor 27 connected with the first switch valve 26, wherein the first switch valve 26 corresponds to a rubber sleeve 28, and a confining pressure tracking pump inner sensor 25 is arranged in the confining pressure tracking pump 24. One end of the confining pressure tracking pump 24 is connected with the first liquid storage container 23 through a connecting pipeline, the other end of the confining pressure tracking pump is connected with the fourth sensor 27 through the first switch valve 26, and the fourth sensor 27 is connected with the rubber sleeve 28 through a connecting pipeline. Gum cover 28, open and move face 30, high strength bolt 31, its characterized in that: the rubber sleeve 28 distributed on the twelve edges is used for sealing the edges of the test piece so as to ensure that seepage liquid or gas completely passes through the test piece, and the seepage sealing system is used for injecting pressure into the rubber sleeve 28 so as to enable the rubber sleeve to expand for sealing;

the seepage sealing system operates as follows: the first liquid storage container 23 is filled with sufficient water, the water flows into the rubber sleeve through the seepage seal pump 24 and the first switch valve 26 and the fourth sensor 27, and the injection is stopped when the water pressure in the rubber sleeve reaches a set value.

The back pressure system of this embodiment mainly includes: the hydraulic control system comprises a second liquid storage container 32, a back pressure pump 33 connected with the second liquid storage container 32, a second switch valve 35 connected with the back pressure pump 33, a back pressure buffer container 36 connected with the second switch valve 35, a fifth sensor 37 connected with the back pressure buffer container 36, and a back pressure valve 38 connected with the fifth sensor 37, wherein a back pressure pump internal sensor 34 is arranged in the back pressure pump 33, and the fifth sensor 37 corresponds to the pressure bearing plate 29. One end of the back pressure pump 33 is connected with the second liquid storage container 32 through a pipeline, the other end of the back pressure pump is connected with the back pressure buffer container 36 through a second switch valve 35, and a fifth sensor 37 is connected between the back pressure buffer container 36 and the back pressure valve 38 and is connected into a middle small hole of the pressure bearing plate 29 opposite to the seepage system connection pressure bearing plate 29 in the three-shaft loading chamber 49.

The main process of the operation of the back pressure system is as follows: the second liquid storage container 32 is filled with water, the water is output by a back pressure pump 33, flows into a back pressure buffer container through a second switch valve 35, and then outputs a certain pressure to the back pressure valve, wherein the sensor is used for loading a pressure regulating device which is higher than the atmospheric pressure till the simulated formation pressure at a seepage outlet, so that the effluent liquid is stable, and the metering precision is improved. The gas or liquid that the seepage flow flows out has certain pressure, and triaxial pressure also can cause inside pressurized great, consequently needs certain steady voltage operation when flowing out, and triaxial pressure is simulation formation pressure promptly.

The data acquisition system of the embodiment mainly comprises: a plurality of ultrasonic probes 44 installed in the pressure bearing plate 29, one ultrasonic transmitter-receiver 45 connected to the plurality of ultrasonic probes 44, a wireless router 46 connected to the ultrasonic transmitter-receiver 45, an operating system 47 wirelessly connected to the wireless router 46, and a data storage center 48 wirelessly connected to the wireless router 46. A plurality of ultrasonic probes 44 are embedded in an array in a pair of opposite pressure bearing plates 29 of the triaxial loading system, an ultrasonic transmitter-receiver 45 is connected with the plurality of ultrasonic probes 44, and data received by the ultrasonic transmitter-receiver 45 is transmitted to a data storage center 48 through a wireless router 46. The arrangement mode of the acoustic wave probes is an array arrangement mode, multiple arrangement modes such as a 2 x 2 array, a 2 x 3 array, a 2 x 4 array and a 3 x 3 array can be selected according to the measurement precision, and the data transmission mode adopts a wireless router 46 transmission mode. The ultrasonic probe 44 is provided with an ultrasonic transmitting end 50 and an ultrasonic probe signal line 53, and the ultrasonic transmitter-receiver 45 is provided with an ultrasonic receiving end 51.

The working process of the data acquisition system is as follows: the operating system 47 issues an acquisition instruction, the instruction is issued to the ultrasonic transmitting and receiving device 45 through the wireless router 46, then the ultrasonic transmitting end 50 transmits ultrasonic waves, the ultrasonic waves are received by the ultrasonic receiving end 51 through the test piece, return to the ultrasonic transmitting and receiving device 45, and are transmitted to the data storage center 48 through the wireless router 46 to be stored and can be checked in the operating system. In addition, the data acquisition system stores data which can be acquired by each sensor of each system.

The liquid injection seepage system of the present embodiment includes: the precise injection pump comprises a third liquid storage container 18, a precise injection pump 19 connected with the third liquid storage container 18, a first electromagnetic valve 21 connected with the precise injection pump 19 and a back pressure valve 38, a sixth sensor 22 connected with the first electromagnetic valve 21, a third switch valve 41 connected with a pressure bearing plate 29, a gas-liquid separator 39 connected with the back pressure valve 38, a wet flowmeter 40 arranged on the gas-liquid separator 39, and an electronic balance 43 connected with the gas-liquid separator 39, wherein a precise injection pump in-pump sensor 20 is arranged in the precise injection pump 19. One end of the precision injection pump 19 is connected with the third liquid storage container 18, the other end of the precision injection pump is connected with the sixth sensor 22 through the first electromagnetic valve 21, and pipelines of the connected devices are pressure-bearing pipes 60; the small hole on the bearing plate 29 in the triaxial loading chamber is connected with a back pressure valve 38 through a third on-off valve 41, the back pressure valve 38 is connected with a gas-liquid separator 39, one end of the gas-liquid separator 39 is connected with a wet flowmeter 40, and the other end of the gas-liquid separator 39 is connected with a pipeline and extends into a water collection container 42 on an electronic balance 43.

The gas injection system of the present embodiment includes: the gas cylinder 7, a fourth switch valve 8 connected with the gas cylinder 7, a gas compression pump 11 connected with the fourth switch valve 8, a second electromagnetic valve 9 connected with the gas compression pump 11, a fifth switch valve 12 connected with the gas compression pump 11, a buffer container 13 connected with the fifth switch valve 12, a sixth switch valve 14 connected with the buffer container 13, a seventh sensor 15 connected with the sixth switch valve 14, a third electromagnetic valve 17 connected with a pressure bearing plate 29, and a pressure regulating valve 16 connected with the third electromagnetic valve 17. The gas bottle 7 is connected with a gas compression pump 11 through a fourth switch valve 8, a pressure gauge 10 is connected with the gas compression pump 11 through a second electromagnetic valve 9, and the gas compression pump 11 is connected with a buffer container 13 through a fifth switch valve 12; the other end of the buffer container 13 is connected with a seventh sensor 15 through a sixth switching valve 14, the seventh sensor 15 is connected with a pressure regulating valve 16, and the pressure regulating valve 16 is connected with a triaxial loading chamber 49 through a third electromagnetic valve 17.

The operation process of the gas seepage system is as follows: seepage gas is stored in the gas cylinder 7 and flows into the gas compression pump 11 through the fourth switch valve 8, wherein the pressure gauge 10 displays the pressure in the gas cylinder, and the second electromagnetic valve 9 is used for controlling the pressure in the gas cylinder to be lower than a limit value for pressure compensation. The pressurized seepage gas is output and reaches the buffer container through the fifth switch valve 12, then reaches the pressure regulating valve 16 through the sixth switch 14 and the seventh sensor 15, the third electromagnetic valve 17 controls the output gas with set pressure to enter a seepage injection face interface, the pressurized gas liquid flows into the seepage injection face of the test piece through the seepage injection face interface and the central connecting hole 52 of the pressure bearing plate 29, and the pressurized gas liquid seeps through the test piece. Flows out through the central connecting hole 52 of the opposite pressure bearing plate, stably flows to the gas-liquid separator 39 through the third switch valve 41 and the back pressure valve 38, is separated, and then flows to the relevant gas collecting device for collection and weighing.

Example 1.1: five of the pressure bearing plates 29 of six faces of the seepage cube are fixed on the kettle body, the other face is an open moving face, and the open moving face is sealed by matching 18 high-strength bolts 31 with a pressure bearing cover plate 30;

the first sensor 4, the second sensor 5 and the third sensor 6 are all pressure sensors and are used for recording pressure values loaded by three shafts; the sound wave probe is embedded in the pressure bearing plate 29 and is used for recording the seepage condition; the pressure gauge 10 is used for recording the pressure of the gas in the gas cylinder 7 so as to supplement the pressure; the seventh sensor 15 is used for recording the pressure of the injected gas during seepage, the sensors in the precision injection pump 19, the confining pressure tracking pump 24 and the back pressure pump 33 are used for monitoring parameters such as the pump pressure, flow rate and flow rate in the precision injection pump 19, the sixth sensor 22 is used for recording the pressure of the injected liquid during seepage, the fourth sensor 27 is used for recording the pressure of the injected confining pressure, and the fifth sensor 37 is used for recording the back pressure. The data analysis system can automatically analyze the data acquired by various sensors and characterize the liquid flowing condition in the seepage process.

Example 2: the experimental method of the seepage system of the embodiment comprises the following steps:

s1, manufacturing a seepage test piece by using a large-size mold according to a specified proportion, and repairing a place with a damaged edge by using epoxy resin glue after the seepage test piece is solidified and is demoulded by using a demould tool so as to ensure that a seepage sealing system can effectively seal the test piece;

and S2, placing the test piece into a cubic cavity of the triaxial loading chamber, and fixing the open movable surface on the triaxial loading chamber by using a high-strength bolt 31 to form an externally sealed whole. Setting a three-axis axial pressure to reach the simulated axial pressure;

s3, filling water into the first liquid storage container 23, opening the first switch valve 26, setting the confining pressure, starting the confining pressure tracking pump 24 to inject water into the rubber sleeve 28, stopping the confining pressure tracking pump 24 when the preset pressure is reached, and closing the first switch valve 26; because the rubber sleeve has larger capacity, sufficient water can be injected to fill the rubber sleeve with water and provide larger sealing pressure, so that the operation is carried out in a way of filling water once before each experiment in order to avoid carrying out water injection operation again in the experiment process;

s4, opening a third electromagnetic valve 17 or a first electromagnetic valve of the seepage system and a data acquisition and analysis system; opening the back pressure system, opening the third switch valve 41, and connecting the cavity with the atmosphere;

s5, respectively utilizing a gas injection system and a liquid injection system in the seepage system to perform seepage experiments on the coal rock;

s6, after the experiment is finished, closing the seepage system, the back pressure system and the three-axis loading system, and closing the data acquisition and analysis system under the condition of determining data storage, wherein the judgment basis of the experiment finishing is that the indication number of the flow velocity sensor is stable, and seepage gas or liquid flows out at a constant speed;

and S7, discharging the pressurized water in the rubber sleeve 28, then detaching the high-strength bolt 31 with the moving surface opened, and then unloading the test piece.

When a gas seepage test is carried out, firstly, observing whether the pressure of gas in the gas cylinder 7 reaches a set pressure or not, and not reaching the operation of electrifying and supplementing the pressure;

the electrifying voltage supplementing process comprises the following steps: the pressure of the gas permeating into the gas cylinder can be observed according to the indication of the pressure gauge 10, if the observed gas pressure is lower, the gas quantity in the permeation process can be lack, and the set permeation pressure can not be reached. At this time, the pressure compensation operation needs to be performed by electrifying, the pressure set by the gas compression pump 11 after electrification according to the pressure set by the second electromagnetic valve 9 comprises the lowest pressure and the highest pressure, the pressure compensation is performed when the pressure is lower than the lowest pressure, and the pressure compensation is stopped when the highest pressure is reached.

The effect is to provide sufficient osmotic pressure and gas to enable the osmotic process to be completed.

Firstly, setting a pressure regulating valve, setting a required constant pressure, then opening the fourth switch valve 8, and then opening the third electromagnetic valve 17, the fifth switch valve 12, the sixth switch valve 14 and the third switch valve 41; the gas permeation test can be carried out, and during the experiment, the gas in the gas bottle 7 is filled into the buffer container 13, and then the gas with stable and proper pressure is output by the pressure regulating valve; after the seepage gas passes through the test piece, the seepage gas passes through a pipeline and enters a back pressure system through a switch 7, and after the seepage gas is separated by a gas-liquid separator 39, the seepage gas can be recycled;

when a liquid seepage test is carried out, the third liquid storage container 18 is filled, the injection pressure of the precision injection pump 19 is set, then the first electromagnetic valve and the third switch valve 41 are opened, and then the precision injection pump 19 is started to start the liquid seepage test; the seepage liquid flows from the third liquid storage container 18 through the precision injection pump 19 and then is connected to the small hole in the center of the pressure bearing plate 29 through a pipeline, and after passing through the test piece, the seepage liquid flows out through the small hole in the center of the pressure bearing plate 29 opposite to the test piece, flows to the gas-liquid separator 39 through the third on-off valve 41 and the back pressure system, is separated by the gas-liquid separator 39, flows through the wet flowmeter, and reaches the water collection container 42 on the electronic balance 43.

Example 3: referring to fig. 7 to 11, the connection between the systems of the present embodiment is performed through pressure-bearing pipes 60, and a connection assembly 61 is installed between two adjacent pressure-bearing pipes 60, so as to facilitate a user to quickly connect two adjacent pressure-bearing pipes 60, the following embodiments are proposed;

the pressure-bearing pipe 60 comprises a first end part 62 and a second end part 63, the connecting assembly 61 comprises a plurality of first baffle plates 64 uniformly arranged on the peripheral side of the first end part 62, a plurality of notches 65 are formed on the peripheral side of the first end part 62, push blocks 66 are elastically matched in the notches 65, and clamping balls corresponding to the push blocks 66 are arranged in the notches 65;

the connecting assembly 61 further comprises a sleeve 67 sleeved on the periphery of the second end 63, a plurality of second baffles 68 are arranged on the periphery of the inner wall of the sleeve 67, the plurality of second baffles 68 correspond to the plurality of first baffles 64, a lantern ring 69 is arranged in the sleeve 67, the lantern ring 69 is sleeved on the periphery of the second end 63, and limiting holes 70 corresponding to the notches 65 in a one-to-one mode are formed in the periphery of the inner wall of the lantern ring 69.

Through the sleeve 67 that sets up, the user of can being convenient for is pressed close to the first end 62 of one of them pressure-bearing pipe 60 and the second end 63 of another pressure-bearing pipe 60 and is placed, and make sleeve 67 cup joint in the week side of first end 62, rotate pressure-bearing pipe 60, make first baffle 64 and second baffle 68 rotate, the extrusion, thereby accomplish the connection between two adjacent pressure-bearing pipes 60, reach the effect of high-speed joint, through the ejector pad 66 that sets up, can be at the in-process that pressure-bearing pipe 60 connects, drive the card ball through elasticity and remove in notch 65, and accomplish the connection back at two pressure-bearing pipes 60, extrude the card ball, make the card ball card block in spacing hole 70, thereby spacing sleeve 67, reduce the not hard up condition of connecting between two pressure-bearing pipes 60.

The first baffle plates 64 and the second baffle plates 68 of the present embodiment are both arc-shaped, and the end portions thereof are provided with inclined surfaces, a first passing groove 71 is provided between two adjacent first baffle plates 64, a second passing groove 72 is provided between two adjacent second baffle plates 68, the first passing groove 71 corresponds to the second baffle plates 68, and the second passing groove 72 corresponds to the first baffle plates 64. Through the inclined plane that sets up, can be convenient for first baffle 64 and second baffle 68 extrude each other, reach the effect that two pressure-bearing pipes 60 are closely laminated, wherein, the rubber pad has all been installed at the both ends of pressure-bearing pipe 60, carries out sealing action, and first groove 71 and second groove 72 of passing through are used for passing through of second baffle 68 and first baffle 64 respectively.

Limiting grooves 73 are formed in the upper side and the lower side of the inner wall of the notch 65, sliding blocks are arranged on the upper side and the lower side of the push block 66, the sliding blocks are in sliding fit in the limiting grooves 73, a chamfer is formed in one side of the push block 66, a spring is arranged between the push block 66 and the inner wall of the limiting groove 73, and the clamping ball corresponds to the limiting hole 70. Through the limiting groove 73, the push block 66 can move along the limiting groove 73 through the sliding block, and the situation that the push block 66 is separated from the limiting groove 73 is reduced. Through the chamfer that sets up, can extrude the card ball when ejector pad 66 removes to spacing groove 73 tip, extrude the card ball to spacing hole 70 in.

In the embodiment, a notch 75 is formed in the lower side of the inner wall of the notch 65, a stopper 76 is slidably fitted in the notch 75, a push rod 77 is mounted on one side of the stopper 76, the push rod 77 corresponds to the collar 69, and the stopper 76 corresponds to the push block 66. The stopper 76 can block the push block 66, and when two adjacent pressure-bearing pipes 60 are connected, the first end 62 is sleeved with the lantern ring 69, the push rod 77 is extruded, the stopper 76 is driven to move, and the limit of the stopper 76 on the push block 66 is released.

The limiting hole 70 of the embodiment penetrates through the sleeve 67, and a sealing plug corresponding to the limiting hole 70 is arranged on the peripheral side of the outer wall of the sleeve 67. Through the arranged sealing plug, a user can take out the clamping ball conveniently, so that the limit of the clamping ball on the sleeve 67 is relieved;

to facilitate removal of the card ball by the user, the following example is proposed:

optionally, a thread groove is formed on the periphery of the inner wall of the limiting hole 70, the sealing plug is a bolt, and the bolt is in threaded fit with the thread groove, so that a user can rotate the bolt conveniently, the ball can be taken out conveniently on one hand, and the clamping position of the ball can be adjusted conveniently by the user on the other hand;

optionally, the sealing plug is a rubber plug, which is convenient for the user to rapidly seal or open the limiting hole 70.

The above embodiments may be combined with each other.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or described herein.

In the description of the present invention, it should be understood that the directions or positional relationships indicated by the directional terms such as "front, back, upper, lower, left, right", "horizontal, vertical, horizontal" and "top, bottom", etc. are usually based on the directions or positional relationships shown in the drawings, and are only for convenience of description and simplification of the description, and in the case of not making a contrary explanation, these directional terms do not indicate and imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore, should not be construed as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Claims (8)

1. The large-size true triaxial coal rock mass multi-field seepage coupling system experimental device is characterized by comprising a triaxial loading system, a seepage sealing system, a back pressure system, a data acquisition and analysis system and a triaxial loading chamber, wherein the seepage system comprises a liquid injection seepage system and a gas injection seepage system;

triaxial load room (49) include triaxial load room steelframe (54), install gum cover (28) on triaxial load room steelframe (54), install a plurality of bearing plate (29) on triaxial load room steelframe (54), connecting hole (52) have been seted up on bearing plate (29), the seepage flow system the back pressure system all with connecting hole (52) are connected.

2. The experimental device for the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 1, wherein a plurality of the triaxial loading chamber steel frames (54) are square frames, the triaxial loading chamber steel frames (54) are provided with a plurality of placing grooves, and the pressure bearing plates (29) are placed in one-to-one correspondence with the placing grooves.

3. The experimental device for the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 1, wherein the triaxial loading system comprises: the loading device comprises an X-axis servo loading system (1), a Y-axis servo loading system (2) and a Z-axis servo loading system (3) which are connected with a bearing plate (29), wherein a first sensor (4), a second sensor (5) and a third sensor (6) are respectively arranged on the X-axis servo loading system (1), the Y-axis servo loading system (2) and the Z-axis servo loading system (3), and an axial loading oil cylinder is arranged on the outer side of the bearing plate (29).

4. The experimental device for the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 1, wherein the seepage sealing system mainly comprises: the device comprises a first liquid storage container (23), a confining pressure tracking pump (24) connected with the first liquid storage container (23), a first switch valve (26) connected with the confining pressure tracking pump (24), and a fourth sensor (27) connected with the first switch valve (26), wherein the first switch valve (26) corresponds to a rubber sleeve (28), and a confining pressure tracking pump inner sensor (25) is arranged in the confining pressure tracking pump (24).

5. The experimental device for the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 1, wherein the back pressure system mainly comprises: the hydraulic control system comprises a second liquid storage container (32), a back pressure pump (33) connected with the second liquid storage container (32), a second switch valve (35) connected with the back pressure pump (33), a back pressure buffer container (36) connected with the second switch valve (35), a fifth sensor (37) connected with the back pressure buffer container (36), and a back pressure valve (38) connected with the fifth sensor (37), wherein a back pressure pump inner sensor (34) is arranged in the back pressure pump (33), and the fifth sensor (37) corresponds to a pressure bearing plate (29).

6. The experimental device of the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 1, wherein the data acquisition system mainly comprises: install a plurality of ultrasonic probe (44) in pressure-bearing plate (29), with a plurality of ultrasonic emission receiver (45) that ultrasonic probe (44) are connected, with wireless router (46) that ultrasonic emission receiver (45) are connected, with operating system (47) of wireless router (46) wireless connection, with data storage center (48) of wireless router (46) wireless connection.

7. The experimental device for the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 5, wherein the liquid injection seepage system comprises: third receiver (18), with precision injection pump (19) that third receiver (18) is connected, with precision injection pump (19) with first solenoid valve (21) that backpressure valve (38) are connected, with sixth sensor (22) that first solenoid valve (21) are connected, with third ooff valve (41) that pressure-bearing plate (29) are connected, with vapour and liquid separator (39) that backpressure valve (38) are connected, install wet flowmeter (40) on vapour and liquid separator (39), with electronic balance (43) that vapour and liquid separator (39) are connected is equipped with sensor (20) in the precision injection pump (19).

8. The experimental device for the large-size true triaxial coal-rock mass multi-field seepage coupling system according to claim 1, wherein the gas injection system comprises: the gas compressor comprises a gas cylinder (7), a fourth switch valve (8) connected with the gas cylinder (7), a gas compression pump (11) connected with the fourth switch valve (8), a second electromagnetic valve (9) connected with the gas compression pump (11), a fifth switch valve (12) connected with the gas compression pump (11), a buffer container (13) connected with the fifth switch valve (12), a sixth switch valve (14) connected with the buffer container (13), a seventh sensor (15) connected with the sixth switch valve (14), a third electromagnetic valve (17) connected with a pressure bearing plate (29) and a pressure regulating valve (16) connected with the third electromagnetic valve (17).

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