CN111208047A - Test method capable of simulating permeability of fractured rock mass under complex disturbance condition - Google Patents

Abstract

Translated fromChinese

本发明公开了一种可模拟复杂扰动条件下破碎岩体渗透性试验方法，可以在单独的静载试验或动载试验的基础上实现静载试验+原位扰动载荷试验、或动载试验+原位扰动载荷试验，进而可以精确地模拟破碎岩体在复杂原位扰动条件下的静载荷、冲击载荷、长时稳定载荷、周期性脉冲及振动载荷、实测扰动载荷、渗流压力等环境，扰动载荷控制精度高、模拟动载荷的复杂程度高、监测数据全面、自动化程度高，便于研究多种岩样混合分层布置形式下复杂动载荷作用下破碎岩体内部的渗透压力梯度的响应规律及机理，可以为研究胶结破碎岩体重构隔水层渗透性等关键科学问题提供重要的试验平台和更准确的试验数据。

The invention discloses a permeability test method for broken rock mass that can simulate complex disturbance conditions, and can realize static load test + in-situ disturbance load test or dynamic load test + dynamic load test on the basis of separate static load test or dynamic load test The in-situ disturbance load test can accurately simulate the static load, impact load, long-term stable load, periodic pulse and vibration load, measured disturbance load, seepage pressure and other environments of broken rock mass under complex in-situ disturbance conditions. High load control accuracy, high complexity of simulated dynamic load, comprehensive monitoring data, and high degree of automation, it is convenient to study the response law of the seepage pressure gradient inside the broken rock mass under the action of complex dynamic load under the mixed and layered arrangement of various rock samples. The mechanism can provide an important test platform and more accurate test data for the study of key scientific issues such as the permeability of the cemented and broken rock mass to reconstruct the aquifer permeability.

Description

Test method capable of simulating permeability of fractured rock mass under complex disturbance condition

Technical Field

The invention relates to a rock mass test device, in particular to a compaction and permeability coupling test device for simulating a broken rock mass under the action of complex in-situ disturbance and impact load, and belongs to the field of geotechnical engineering test technology and equipment.

Background

In the underground resource exploitation process, the overlying strata of the goaf can generate violent movement under the action of mine pressure, so that roof fracture and collapse can be caused, a groundwater system can be damaged, the broken rock body can be gradually compacted under the action of upper strata load after being stabilized, the permeability of the collapsed broken rock body also changes remarkably, and water is often accompanied with the loss of horizontal particles with different particle sizes in the seepage process of the broken rock body, so that the rearrangement of the particles in the broken rock body and the change of compaction characteristics are caused, and finally the subsidence change of the earth surface is caused. Under the guidance of the concept of 'green mining' and 'scientific mining' at the present stage, the solid filling mining technology is developed importantly, and the broken rock mass or cemented broken rock mass for filling plays an important role in controlling the deformation of the earth surface and protecting the aquifer. Thus, the permeability during compaction of a crushed rock mass that has collapsed and filled has a significant impact on the protection of the groundwater system.

However, under the influence of dynamic loads such as collapse impact of the upper rock strata, vibration disturbance of the construction machine, and periodic pushing and tamping of the filling equipment, the mechanical behavior of the fractured rock mass after collapse, such as deformation, fracture, and infiltration, becomes more complicated. In this context, many research works on key scientific issues are urgently needed, such as: the impact disturbance influences the rearrangement effect of the broken rock mass, the periodic vibration compaction influences the compactness of the broken rock mass, the complex in-situ engineering disturbance influences the permeability of the broken rock mass and the like. Due to the heterogeneity, structure and surface shape diversity and randomness of the fractured rock mass and the research on various complex problems related to particle movement, fracture, damage, infiltration and the like, the research means adopting theory and numerical simulation has obvious limitations, and laboratory tests are one of the main research means in the field.

① is generally simply tested by using a universal testing machine, the equipment adaptability is poor, the coupling test of compaction, permeation and power cannot be simultaneously carried out on the broken rock, ② is generally applied to a rock sample by simplified impact dynamic load, the control and application of dynamic load are simple, the real and complex dynamic load signals of vibration, impact and the like obtained by field test cannot be accurately applied to the broken rock in a laboratory, the actual situation cannot be reflected, the experimental result and the actual deviation are larger, ③ is single in monitored obtained parameters, the monitoring result of the broken rock test at the present stage is mostly the loss quality of particles of inlet and outlet liquid pressure, flow, static load force, displacement, uncontrollable particle size and the like, the loss characteristics of particles determining the flow characteristics of the particles of the broken rock wall, the surface seepage flow path, the seepage pressure distribution of the inner part of the pressure chamber, the maximum lateral pressure control, the mass of the testing machine, the inaccurate quality control of the particles, the loss of the particles of the crushed rock, the detachment of the particle size, the inaccurate quality control, the inaccurate and the problem of the particle size loss of the particle breakage of the particle breaking test chamber, the difficulty in the low-breaking load and the difficulty in the mounting and detaching operation of the vacuum test chamber, the low-load-forming of the particle-breaking-pressure-based on-pressure monitoring and-load-pressure monitoring parameters of the actual-based on-load monitoring of the parameters of the broken.

Therefore, the developed method for testing the permeability of the fractured rock mass, which has the advantages of high disturbance load control precision, high complexity of simulating dynamic load, comprehensive monitoring data, high automation degree and simplicity in operation, plays an important role in promoting the research in the technical field of green water-retaining mining and has important practical value.

Disclosure of Invention

Aiming at the problems, the invention provides a permeability test method of a fractured rock mass under a simulated complex disturbance condition, which can monitor the distribution condition of the permeability pressure along the loading direction, obtain the fractal dimension of the fractured rock mass, the evolution of the seepage path, the number of surface cracks, the opening degree and other test parameters on the premise of automatically inverting a complex in-situ disturbance load and simulating a complex dynamic load, and provide more accurate test data for researching the response rule and mechanism of the permeability pressure gradient in the fractured rock mass under the action of the complex dynamic load.

In order to achieve the purpose, the fractured rock mass permeability test system comprises an integral frame, a pressure chamber part, a pressure loading control part, a permeable liquid supply control part, an in-situ disturbance excitation control part, a visual detection part and a centralized electric control part;

the pressure loading control part is fixedly arranged at the inner bottom of the integral frame and comprises a hydraulic pump station and a loading hydraulic cylinder, the loading hydraulic cylinder is vertically and fixedly arranged on the integral frame, the telescopic end of the loading hydraulic cylinder is vertically and upwards ejected out, and the loading hydraulic cylinder is connected with the hydraulic pump station through a hydraulic pipeline and a control valve group;

the pressure chamber part comprises a pressure chamber arranged in the integral frame, and the pressure chamber comprises a pressure chamber base, a visual pressure chamber cylinder wall and a pressure chamber top cover; the pressure chamber base is coaxially detachably positioned and installed at the top end of a telescopic end of the loading hydraulic cylinder through a pressure chamber base positioning installation part, a seepage outlet channel penetrating through the pressure chamber base is arranged inside the pressure chamber base, the inlet end of the seepage outlet channel is communicated with the top plane of the pressure chamber base, the outlet end of the seepage outlet channel is connected with a seepage processing device through an outlet seepage flow sensor, the bottom of the visual pressure chamber cylinder wall is coaxially and hermetically fixed on the pressure chamber base, the visual pressure chamber cylinder wall and the pressure chamber base jointly form a barrel-shaped structure, a plurality of seepage water pressure sensors are uniformly distributed on the inner wall of the visual pressure chamber cylinder wall from top to bottom, a cylinder wall side pressure dynamic sensor is further arranged on the inner wall of the visual pressure chamber cylinder wall, a lower water permeable plate, the outer diameter of which is matched with the inner diameter of the visual pressure chamber cylinder wall, is arranged at, A plurality of water permeable through holes communicated with the percolate outlet channel are uniformly distributed on the lower water permeable plate; the pressure chamber top cover is coaxially arranged at the top of the visual pressure chamber cylinder wall, the outer diameter of the pressure chamber top cover is matched with the inner diameter of the visual pressure chamber cylinder wall, a liquid inlet hole penetrating through the pressure chamber top cover is formed in the pressure chamber top cover, an orifice liquid injection pressure sensor is arranged at the orifice position of the liquid inlet hole, an upper water permeable plate with the outer diameter matched with the inner diameter of the visual pressure chamber cylinder wall is fixedly arranged at the bottom of the pressure chamber top cover, and a plurality of water permeable through holes communicated with the liquid inlet hole are uniformly distributed in the upper water permeable plate; the seepage treatment device comprises a solid-liquid separation mechanism, and an electronic scale for weighing the discharged sample rock particles is arranged on the solid-liquid separation mechanism;

the seepage liquid supply control part comprises a seepage liquid pumping device and a seepage pumping electric control device electrically connected with the seepage liquid pumping device, wherein the input end of the seepage liquid pumping device is connected with a seepage liquid supply box through a pipeline, and the output end of the seepage liquid pumping device is communicated and connected with a liquid inlet hole through a pipeline;

the in-situ disturbance excitation control part comprises a disturbance signal execution device and a disturbance signal excitation electric control device; the disturbance signal execution device comprises a positioning pressure head and a positioning pressure seat, the positioning pressure seat is coaxially and fixedly arranged at the top of the pressure chamber top cover, the position of the positioning pressure head, which corresponds to the positioning pressure seat, is vertically arranged on the integral frame, the positioning pressure head is provided with a positioning pressure head lifting structure, the bottom of the positioning pressure head and the top of the positioning pressure seat are of spherical structures which are arranged in a matched manner, the positioning pressure head is provided with an alternating current excitation coil, the positioning pressure seat is provided with a direct current excitation coil, and the positioning pressure head or the positioning pressure seat is also provided with an in-situ disturbance; the disturbance signal excitation electric control device comprises a controllable alternating current excitation module and a direct current power supply module, wherein the controllable alternating current excitation module is electrically connected with an alternating current excitation coil, and the direct current power supply module is electrically connected with a direct current excitation coil;

the visual detection part comprises a digital image collector, and the digital image collector is positioned, erected and installed corresponding to the wall of the visual pressure chamber;

the centralized electric control part comprises a computer, a data acquisition module, a pressure loading control loop, a liquid injection control loop, an in-situ disturbance excitation control loop, a visual detection control loop and a data analysis and calculation loop, wherein the computer is respectively and electrically connected with a hydraulic pump station, a seepage pumping electric control device, a disturbance signal excitation electric control device and the data acquisition module, and the data acquisition module is respectively and electrically connected with electronic scales of a seepage water pressure sensor, an orifice liquid injection pressure sensor, an outlet seepage flow sensor, a cylinder wall side pressure dynamic sensor, an in-situ disturbance dynamic pressure sensor, a digital image acquisition device and a seepage processing device;

the specific test method comprises the following steps:

a. preparation of the test: the method comprises the following steps of placing a crushed rock mass sample into a pressure chamber, then additionally installing a pressure chamber top cover provided with a positioning pressure seat, adjusting a lifting structure on a positioning pressure head to enable the positioning pressure head to move upwards and move backwards, sending the pressure chamber into an integral frame, coaxially positioning and installing a pressure chamber base at the top end of a telescopic end of a loading hydraulic cylinder through a positioning structure on the top surface of the telescopic end of the loading hydraulic cylinder and a pressure chamber base positioning installation part, adjusting the lifting structure on the positioning pressure head again to enable the positioning pressure head to descend, and connecting a water pipeline and an electric pipeline after the positioning pressure head is close to the positioning;

b. the test process comprises the following steps: the computer controls the hydraulic pump station to work through the pressure loading control loop so that the loading hydraulic cylinder jacks up to input pressure load to the broken rock mass sample in the pressure chamber, and simultaneously the computer controls the seepage pumping electric control device to work through the liquid injection control loop so that seepage liquid is injected into the broken rock mass sample in the pressure chamber through the liquid inlet, and the computer controls the digital image collector to work through the visual detection control loop; the osmotic water pressure sensor feeds back water pressure data of osmotic liquid flowing through the osmotic water pressure sensor in the pressure chamber to the data acquisition module in real time, and the computer calculates and establishes a water pressure distribution model of osmotic pressure of the osmotic water in the pressure chamber along the loading direction according to the osmotic water pressure sensor data acquired by the data acquisition module and a built-in program; the digital image collector sends image data of a broken rock sample observed through a visual pressure chamber cylinder wall to the data collection module according to a set time interval, the in-situ disturbance dynamic pressure sensor feeds back pressure data borne by a pressure chamber top cover to the data collection module in real time, the orifice injection pressure sensor feeds back initial pressure data of injected seepage to the data collection module in real time, the outlet seepage flow sensor feeds back discharged seepage pressure data to the data collection module in real time, the cylinder wall side pressure dynamic sensor feeds back confining pressure data of the visual pressure chamber cylinder wall on the broken rock sample to the data collection module in real time, an electronic scale of the seepage processing device feeds back quality data of the leaked rock particles to the data collection module, and the computer firstly respectively feeds back the image data of the digital image collector collected by the data collection module, the pressure data borne by the pressure chamber top cover, the pressure data of the pressure chamber top cover, Performing error analysis calculation and mean value output on the injected seepage initial pressure data, the discharged seepage pressure data, the confining pressure data and the discharged rock particle quality data, and then constructing a fractured rock mass fractal dimension model, a seepage path evolution model, a surface crack model and a surface crack opening model according to a built-in gray image fractal dimension analysis program, a seepage path digital reconstruction program and a fractured rock mass surface crack statistical program;

when a static load test is carried out, the computer controls the loading hydraulic cylinder to output a stable rated static load, and the condition that the broken rock mass bears a long-term stable load is simulated;

when a static load and preset dynamic load test is carried out, the size of a static load, the loading speed, the form, the period, the amplitude, the peak value, the cycle times and the superposition mode characteristic data of the dynamic load are set in a computer, then the computer controls a loading hydraulic cylinder to output stable rated static load, simultaneously, the computer controls a disturbance signal to excite an electric control device to work through an in-situ disturbance excitation control loop so that a direct current excitation coil and an alternating current excitation coil generate magnetic flux, electromagnetic force is generated between a positioning pressure head and a positioning pressure seat so that the positioning pressure head and the positioning pressure seat generate relative excitation to realize static load disturbance, and the conditions that a crushed rock body bears the periodic disturbance load and the superposition action of the impact load in a preset form while bearing a long-term stable load are simulated;

when a static load + in-situ disturbance load or a modified in-situ disturbance load test is carried out, setting the size and the loading speed of the static load in a computer, then introducing an in-situ disturbance signal measured on site into the computer, and then setting an intervention condition of in-situ disturbance in the computer, or firstly carrying out artificial modification on the in-situ disturbance signal and then setting the modified in-situ disturbance intervention condition; and then the computer controls the loading hydraulic cylinder to output a stable rated static load, and simultaneously monitors the static load loading state, when the static load loading condition reaches a set in-situ disturbance intervention condition, the computer controls a disturbance signal to excite the electric control device to work through the in-situ disturbance excitation control loop so that the direct current excitation coil and the alternating current excitation coil generate magnetic flux, electromagnetic force is generated between the positioning pressure head and the positioning pressure seat so that the positioning pressure head and the positioning pressure seat generate relative excitation to realize in-situ disturbance or modified in-situ disturbance, and the condition that the crushed rock body bears the in-situ disturbance load or the modified in-situ disturbance load while bearing the static load is simulated.

As a further improvement scheme of the invention, the bottom of the visual pressure chamber cylinder wall of the fractured rock mass permeability test system is detachably and fixedly arranged on the pressure chamber base; the broken rock mass test system also comprises a pressure chamber top cover dismounting part, wherein the pressure chamber top cover dismounting part comprises a pressure chamber top cover lifting control mechanism arranged on the integral frame and a positioning pressure seat clamping mechanism arranged on the pressure chamber top cover lifting control mechanism, the positioning pressure seat clamping mechanism is used for clamping and positioning a positioning pressure seat when the pressure chamber top cover is dismounted after the test is finished, the pressure chamber top cover lifting control mechanism is used for lifting the positioning pressure seat when the pressure chamber top cover is dismounted after the test is finished, and the pressure chamber top cover lifting control mechanism and the positioning pressure seat clamping mechanism are respectively and electrically connected with a computer;

and c, after the step b is completed, when the pressure chamber top cover is disassembled, the positioning pressure seat is lifted by controlling the pressure chamber top cover lifting control mechanism and the positioning pressure seat clamping mechanism to separate the pressure chamber top cover from the compact integrated structure crushed rock mass sample, after the pressure chamber top cover is disassembled and the pressure chamber is moved out of the integral frame, the visual pressure chamber cylinder wall is separated from the compact integrated structure crushed rock mass sample by injecting water into the pressure chamber and disassembling the visual pressure chamber cylinder wall.

As an implementation mode of the invention, the pressure chamber top cover lifting control mechanism is a gear rack structure which is arranged relative to the center of the pressure chamber top cover and symmetrically, and comprises a rack guide rail and a driving gear, wherein the rack guide rail is vertically and fixedly arranged on an integral frame; the positioning pressing seat clamping mechanism is a horizontal telescopic clamping structure and comprises a telescopic loading and unloading arm horizontally arranged on the driving gear supporting frame, and a top cover loading and unloading hole is also formed in the position, corresponding to the telescopic loading and unloading arm, on the positioning pressing seat;

when the top cover of the pressure chamber is disassembled, the driving gear is controlled to act to enable the telescopic loading and unloading arm to load and unload the hole of the top cover, then the telescopic loading and unloading arm is controlled to extend out and penetrate into the loading and unloading hole of the top cover, and then the driving gear is controlled to act to enable the driving gear support frame to be integrally lifted, so that the top cover of the pressure chamber is disassembled.

As another embodiment of the invention, the pressure chamber top cover lifting control mechanism is a hydraulic cylinder structure symmetrically arranged relative to the center of the pressure chamber top cover, and comprises a positioning pressure seat lifting hydraulic cylinder, wherein the positioning pressure seat lifting hydraulic cylinder is arranged in a manner that the cylinder bottom end is low and the telescopic end is high in inclination; the positioning pressing seat clamping mechanism is a bayonet clamping structure and comprises a clamping fixture block which is hinged to the end part of the telescopic end of the positioning pressing seat lifting hydraulic cylinder, and a limiting clamp ring structure is further arranged on the positioning pressing seat at a position corresponding to the clamping fixture block;

when the pressure chamber top cover is disassembled, the control positioning pressure seat lifting hydraulic cylinder extends to enable the clamping fixture block to be clamped on the limiting clamp ring structure of the positioning pressure seat, the control positioning pressure seat lifting hydraulic cylinder extends, the clamping fixture block is stressed and decomposed into two parts when the positioning pressure seat lifting hydraulic cylinder continues to extend, one part is clamping force along the radial direction of the positioning pressure seat, the other part is lifting force along the axial direction of the positioning pressure seat, and the disassembly of the pressure chamber top cover is realized.

As a further improvement scheme of the invention, a drying mechanism is also arranged on a solid-liquid separation mechanism of a seepage treatment device of the fractured rock mass seepage test system; and b, after the rock mass sample to be crushed is compacted into an integral structure and the discharged seepage pressure data is not fed back by the outlet seepage flow sensor any more, starting the drying mechanism to set time to remove moisture from the leaked and discharged rock particles, and then starting the electronic scale to weigh so as to accurately obtain the quality data of the leaked and discharged rock particles.

As a further improvement scheme of the invention, a replaceable loss particle size control net is also arranged above a lower permeable plate of the fractured rock mass permeability test system, and the aperture of the loss particle size control net is smaller than that of a permeable through hole of the lower permeable plate; and (b) before the crushed rock mass sample is placed into the pressure chamber in the step a, the maximum particle size of particle loss is controlled by replacing the loss particle size control net with different pore diameters.

As a further improvement scheme of the invention, a loading hydraulic cylinder of the fractured rock mass permeability test system is provided with a master cylinder state monitoring sensor electrically connected with a data acquisition module; in the step b, the master cylinder state monitoring sensor feeds back the output pressure data of the loading hydraulic cylinder to the data acquisition module in real time, and the computer simultaneously feeds back the output pressure data of the loading hydraulic cylinder according to the master cylinder state monitoring sensor when constructing the fractured rock fractal dimension model, the seepage path evolution model, the surface crack model and the surface crack opening model.

In one embodiment of the present invention, in step a, the pressure chamber is integrally conveyed into the monolithic frame by hoisting.

As another embodiment of the invention, in the step a, the pressure chamber is integrally conveyed into the integral frame by means of translation conveying.

As a further improvement of the present invention, when the static load + in-situ disturbance load test or the modified in-situ disturbance load test is performed in step b, the artificial modification of the in-situ disturbance signal includes adjusting the peak value of the in-situ disturbance signal to simulate the extreme condition, and adjusting the superimposed periodic load or the impact load to simulate the superimposed influence of various disturbance factors.

Compared with the prior art, the test method for simulating permeability of the fractured rock mass under the complex disturbance condition can realize reduction of in-situ disturbance load obtained by mine field test, can accurately simulate the environments of static load, impact load, long-term stable load, periodic pulse and vibration load, actual measurement disturbance load, seepage pressure and the like of the broken rock mass under the condition of complex in-situ disturbance, the method has the advantages that key test parameters such as dynamic and static loads, pressure of the wall of the pressure chamber, pressure of the pressure chamber inlet, flow of the pressure chamber outlet, outlet loss particle quality, osmotic pressure distribution in the pressure chamber, seepage paths, fracture fractal dimension of fractured rock mass and the like can be monitored in real time, the disturbance load control precision is high, the complexity of simulating the dynamic loads is high, monitored data are comprehensive, the automation degree is high, and the method is more accurate compared with the traditional method of only measuring the inlet pressure and the outlet flow; through setting up the distribution thickness of different kinds of rock specimens and different kinds of rock specimens, be convenient for study multiple rock specimen mix response rule and the mechanism of the osmotic pressure gradient of broken rock mass inside under the complicated dynamic load effect under the layering arrangement form, can provide important test platform and more accurate test data for key scientific problems such as research cemented broken rock mass reconsitution water barrier permeability.

Drawings

FIG. 1 is a schematic structural diagram of a fractured rock mass permeability test system;

FIG. 2 is a schematic structural diagram of a broken rock mass permeability test system when a hydraulic control structure is adopted for a pressure chamber top cover disassembly part;

FIG. 3 is a schematic cross-sectional view of a permeable plate under the fractured rock mass permeability test system;

FIG. 4 is a schematic diagram of the arrangement of a particle size control net for the lost particles in a fractured rock mass permeability test system.

In the figure: 1-integral frame, 2-hydraulic pump station, 3-master cylinder, 4-pressure chamber base, 5-seepage outlet channel, 6-seepage processing device, 9-visual pressure chamber cylinder wall, 10-upper permeable plate, 11-lower permeable plate, 12-cylinder wall side pressure dynamic sensor, 13-fastening bolt, 14-pressure chamber top cover, 15-liquid inlet hole, 16-top cover loading and unloading hole, 17-positioning pressure seat, 19-in-situ disturbance dynamic pressure sensor, 20-alternating current excitation coil, 21-positioning pressure head, 22-driving gear, 23-telescopic loading and unloading arm, 24-rack guide rail, 25-orifice liquid injection pressure sensor, 26-master cylinder state monitoring sensor, 27-digital image collector, 28-testing machine information integrated control module, 29-seepage liquid supply box, 30-seepage liquid pumping device, 31-seepage voltage stabilizing device, 32-seepage pumping electric control device, 33-direct current power supply module, 34-controllable alternating current excitation module, 35-disturbance signal excitation electric control device, 36-computer, 37-osmotic water pressure sensor, 38-pressure chamber and 39-loss particle size control network.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

As shown in figure 1, the fractured rock mass permeability testing system comprises an integral frame 1, a pressure chamber part, a pressure loading control part, a permeable liquid supply control part, an in-situ disturbance excitation control part, a visual detection part and a centralized electric control part.

The pressure loading control part is fixedly arranged at the inner bottom of the integral frame 1 and comprises ahydraulic pump station 2 and a loadinghydraulic cylinder 3, the loadinghydraulic cylinder 3 is vertically and fixedly arranged on the integral frame 1, the telescopic end of the loadinghydraulic cylinder 3 is vertically and upwards ejected, and the loadinghydraulic cylinder 3 is connected with thehydraulic pump station 2 through a hydraulic pipeline and a control valve group.

The pressure chamber part comprises apressure chamber 38 arranged inside the integral frame 1, and thepressure chamber 38 comprises a pressure chamber base 4, a visual pressurechamber cylinder wall 9 and a pressurechamber top cover 14; the pressure chamber base 4 is coaxially, detachably and fixedly arranged at the top end of the telescopic end of the loadinghydraulic cylinder 3 through a pressure chamber base positioning and mounting component, a seepage outlet channel 5 which penetrates through the pressure chamber base 4 is arranged in the pressure chamber base 4, the inlet end of the seepage outlet channel 5 is communicated with the top plane of the pressure chamber base 4, the outlet end of the seepage outlet channel 5 is connected with a seepage processing device 6 through an outlet seepage flow sensor, the bottom of a visual pressurechamber cylinder wall 9 is coaxially, hermetically and fixedly arranged on the pressure chamber base 4, the visual pressurechamber cylinder wall 9 and the pressure chamber base 4 jointly form a barrel-shaped structure, a plurality of seepagewater pressure sensors 37 are uniformly distributed on the inner wall of one side of the visual pressurechamber cylinder wall 9 from top to bottom, a cylinder wall side pressuredynamic sensor 12 is further arranged on theinner wall 9, a lower waterpermeable plate 11 with the outer diameter size matched with the inner diameter size of the visual pressurechamber cylinder wall 9 is arranged at the, as shown in fig. 3, a plurality of water permeable through holes communicated with the permeate outlet channel 5 are uniformly distributed on the lowerpermeable plate 11; the pressurechamber top cover 14 is coaxially arranged at the top of the visual pressurechamber cylinder wall 9, the outer diameter of the pressurechamber top cover 14 is matched with the inner diameter of the visual pressurechamber cylinder wall 9, the pressurechamber top cover 14 is provided with aliquid inlet hole 15 penetrating through the pressurechamber top cover 14, an orificeinjection pressure sensor 25 is arranged at the orifice position of theliquid inlet hole 15, the bottom of the pressurechamber top cover 14 is fixedly provided with an upper waterpermeable plate 10, the outer diameter of the upper waterpermeable plate 10 is matched with the inner diameter of the visual pressurechamber cylinder wall 9, and a plurality of water permeable through holes communicated with theliquid inlet hole 15 are uniformly distributed on the upper waterpermeable plate 10; the percolate treatment device 6 comprises a solid-liquid separation mechanism which can simply adopt a filter screen or a filter bag structure or other solid-liquid separation structures such as a cyclone and the like, and an electronic scale for weighing the discharged sample rock particles is arranged on the solid-liquid separation mechanism.

The seepage liquid supply control part comprises a seepageliquid pumping device 30 and an electric seepage pumping control device 32 electrically connected with the seepageliquid pumping device 30, wherein the input end of the seepageliquid pumping device 30 is connected with a seepageliquid supply box 29 through a pipeline, and the output end of the seepageliquid pumping device 30 is communicated and connected with theliquid inlet hole 15 through a pipeline.

The in-situ disturbance excitation control part comprises a disturbance signal execution device and a disturbance signal excitationelectric control device 35; the disturbing signal executing device comprises apositioning pressure head 21 and apositioning pressure seat 17, thepositioning pressure seat 17 is coaxially and fixedly arranged at the top of the pressurechamber top cover 14, thepositioning pressure head 21 is vertically arranged on the integral frame 1 corresponding to thepositioning pressure seat 17, a positioning pressure head lifting structure is arranged on thepositioning pressure head 21, the bottom of thepositioning pressure head 21 and the top of thepositioning pressure seat 17 are of spherical structures which are arranged in a matched mode, an alternatingcurrent excitation coil 20 is arranged on thepositioning pressure head 21, a direct current excitation coil is arranged on thepositioning pressure seat 17, and an in-situ disturbingdynamic pressure sensor 19 is further arranged on thepositioning pressure head 21 or thepositioning pressure seat 17; the disturbance signal excitationelectronic control device 35 includes a controllableac excitation module 34 and a dcpower supply module 33, the controllableac excitation module 34 is electrically connected to theac excitation coil 20, and the dcpower supply module 33 is electrically connected to the dc excitation coil.

The visual detection part comprises adigital image collector 27, thedigital image collector 27 is positioned and erected corresponding to the visual pressurechamber cylinder wall 9, and thedigital image collector 27 can be arranged on the other side direction of the visual pressurechamber cylinder wall 9 relative to the osmoticwater pressure sensor 37.

The centralized electric control part comprises acomputer 36, adata acquisition module 28, a pressure loading control loop, a liquid injection control loop, an in-situ disturbance excitation control loop, a visual detection control loop and a data analysis and calculation loop, wherein thecomputer 36 is respectively and electrically connected with thehydraulic pump station 2, the seepage pumping electric control device 32, the disturbance signal excitationelectric control device 35 and thedata acquisition module 28, and thedata acquisition module 28 is respectively and electrically connected with an osmoticwater pressure sensor 37, an orifice liquidinjection pressure sensor 25, an outlet seepage flow sensor, a cylinder wall side pressuredynamic sensor 12, an in-situ disturbancedynamic pressure sensor 19, a digitalimage acquisition unit 27 and an electronic scale of a seepage processing device 6.

Before the test is carried out by using the broken rock mass test system, thepressure chamber 38 with a barrel-shaped structure is formed by fixedly mounting the visual pressurechamber cylinder wall 9 and the pressure chamber base 4, the broken rock mass sample is placed into thepressure chamber 38, the pressurechamber top cover 14 provided with thepositioning pressure seat 17 is additionally mounted, the lifting structure on thepositioning pressure head 21 is adjusted to enable thepositioning pressure head 21 to move upwards and move backwards, thepressure chamber 38 is integrally hoisted or sent into the integral frame 1 through a translation conveyor, the positioning structure on the top surface of the telescopic end of the loadinghydraulic cylinder 3 and the positioning mounting part of the pressure chamber base are used for coaxially positioning and mounting the pressure chamber base 4 on the top end of the telescopic end of the loadinghydraulic cylinder 3, the lifting structure on thepositioning pressure head 21 is adjusted again to enable thepositioning pressure head 21 to descend, and thepositioning pressure seat 17 is attached to a waterway pipeline and.

In the test process, thecomputer 36 controls thehydraulic pump station 2 to work through the pressure loading control loop so that the loadinghydraulic cylinder 3 jacks up to input pressure load to the broken rock mass sample in thepressure chamber 38, meanwhile, thecomputer 36 controls the seepage pumping electric control device 32 to work through the liquid injection control loop so that seepage liquid is injected into the broken rock mass sample in thepressure chamber 38 through theliquid inlet 15, and thecomputer 36 controls thedigital image collector 27 to work through the visual detection control loop; the osmoticwater pressure sensor 37 feeds back the water pressure data of the osmotic liquid flowing through the osmoticwater pressure sensor 37 in thepressure chamber 38 to thedata acquisition module 28 in real time, and thecomputer 36 calculates and establishes a water pressure distribution model of the osmotic pressure of the osmotic water in thepressure chamber 38 along the loading direction according to the data of the osmoticwater pressure sensor 37 acquired by thedata acquisition module 28 and a built-in program; thedigital image collector 27 sends image data of a broken rock sample observed through a visual pressurechamber cylinder wall 9 to thedata collection module 28 according to a set time interval, the in-situ disturbancedynamic pressure sensor 19 feeds back pressure data borne by the pressurechamber top cover 14 to thedata collection module 28 in real time, the orificeinjection pressure sensor 25 feeds back initial pressure data of injected seepage liquid to thedata collection module 28 in real time, the outlet seepage liquid flow sensor feeds back discharged seepage liquid pressure data to thedata collection module 28 in real time, the cylinder wall side pressuredynamic sensor 12 feeds back confining pressure data of the visual pressurechamber cylinder wall 9 to the broken rock sample to thedata collection module 28 in real time, an electronic scale of the seepage liquid processing device 6 feeds back quality data of the leaked and discharged rock particles to thedata collection module 28, and thecomputer 36 firstly respectively feeds back image data, image data and leakage data of thedigital image collector 27, acquired by thedata collection module 28, Carrying out error analysis calculation and mean value output on pressure data borne by the pressure chambertop cover 14, initial pressure data of injected seepage liquid, pressure data of discharged seepage liquid, confining pressure data and quality data of discharged rock particles, and then constructing a fractal dimension model of a broken rock body, a seepage path evolution model, a surface crack model and a surface crack opening model according to a built-in gray image fractal dimension analysis program, a seepage path digital reconstruction program and a broken rock body surface crack statistical program;

when a static load test is carried out, thecomputer 36 controls the loadinghydraulic cylinder 3 to output a stable rated static load, so that the condition that the crushed rock mass bears a long-term stable load can be simulated;

when a static load and preset dynamic load test is carried out, characteristic data such as the size of a static load, the loading speed, the form, the period, the amplitude, the peak value, the cycle number, the superposition mode and the like are set in acomputer 36, then thecomputer 36 controls a loadinghydraulic cylinder 3 to output stable rated static load, simultaneously, thecomputer 36 controls a disturbance signal to excite anelectric control device 35 to work through an in-situ disturbance excitation control loop so that a direct current excitation coil and an alternatingcurrent excitation coil 20 generate magnetic flux, electromagnetic force is generated between apositioning pressure head 21 and apositioning pressure seat 17, thepositioning pressure head 21 and thepositioning pressure seat 17 generate relative excitation to realize static load disturbance, and the condition that a crushed rock body bears the load superposition effect such as the periodic disturbance load, the impact load and the like in the preset mode while bearing long-term stable load can be simulated;

when a static load + in-situ disturbance load or a modified in-situ disturbance load test is carried out, the size and the loading speed of the static load are set in thecomputer 36, then an in-situ disturbance signal measured on site is led into thecomputer 36, then intervention conditions of in-situ disturbance are set in thecomputer 36, or the in-situ disturbance signal is manually modified (such as the size of a peak value of the in-situ disturbance signal is adjusted to simulate extreme conditions, and the superposition periodic load or the impact load simulates the superposition influence of various disturbance factors) and then the intervention conditions of the modified in-situ disturbance are set; then thecomputer 36 controls the loadinghydraulic cylinder 3 to output a stable rated static load, thecomputer 36 monitors the static load loading state, when the static load loading condition reaches a set in-situ disturbance intervention condition, thecomputer 36 controls the disturbance signal excitationelectric control device 35 to work through the in-situ disturbance excitation control loop so that the direct current excitation coil and the alternatingcurrent excitation coil 20 generate magnetic flux, electromagnetic force is generated between thepositioning pressure head 21 and thepositioning pressure seat 17, thepositioning pressure head 21 and thepositioning pressure seat 17 generate relative excitation to realize in-situ disturbance or modified in-situ disturbance, and the condition that the crushed rock body bears the in-situ disturbance load or the modified in-situ disturbance load while bearing the static load can be simulated.

Because broken rock mass sample is become closely knit integrative structure by the compaction among the experimental loading process, and annotate the liquid process and make the inside crack of broken rock mass sample fill the osmotic liquid, consequently closely knit integrative broken rock mass sample inside is nearly vacuum state, just so causes experimental completion back pressurechamber top cap 14 and closely knit integrative broken rock mass sample compaction of structure to glue, be difficult to separate, and then causes the sample to be hardly taken out. In order to facilitate taking out a sample, as a further improvement scheme of the invention, the bottom of the visual pressurechamber cylinder wall 9 is coaxially, hermetically and fixedly arranged on the pressure chamber base 4 through afastening bolt 13; the broken rock mass test system also comprises a pressure chamber top cover dismounting part, the pressure chamber top cover dismounting part comprises a pressure chamber top cover lifting control mechanism arranged on the integral frame 1 and a positioning pressure seat clamping mechanism arranged on the pressure chamber top cover lifting control mechanism, the positioning pressure seat clamping mechanism is used for clamping and positioning thepositioning pressure seat 17 when the pressurechamber top cover 14 is dismounted after the test is finished, the pressure chamber top cover lifting control mechanism is used for lifting thepositioning pressure seat 17 when the pressurechamber top cover 14 is dismounted after the test is finished, the pressure chamber top cover lifting control mechanism and the positioning pressure seat clamping mechanism are respectively electrically connected with thecomputer 36, when the pressurechamber top cover 14 is dismounted after the test is finished, thepositioning pressure seat 17 can be lifted by controlling the actions of the pressure chamber top cover lifting control mechanism and the positioning pressure seat clamping mechanism, and further the separation and dismounting of the pressurechamber top cover 14 and the broken rock mass with a compact integrated structure can be realized, after the pressurechamber top cover 14 is completely disassembled and thepressure chamber 38 is moved out of the integral type frame 1, the visual separation and disassembly of the pressurechamber cylinder wall 9 and the sample can be realized by injecting water into thepressure chamber 38 and disassembling thefastening bolt 13.

As an embodiment of the pressure chamber top cover dismounting part of the present invention, the pressure chamber top cover lifting control mechanism is a gear rack structure which is arranged symmetrically with respect to the center of the pressurechamber top cover 14 as shown in fig. 1, and comprises arack guide rail 24 and adrive gear 22, therack guide rail 24 is vertically and fixedly installed on the integral frame 1, thedrive gear 22 with a drive motor is arranged on therack guide rail 24 in a meshing fit manner, and thedrive gear 22 is arranged on the integral frame 1 in a sliding fit manner in the vertical direction through a drive gear support frame, a horizontal limit structure such as a T-shaped groove structure, a dovetail groove structure, etc. is arranged between the drive gear support frame and the integral frame 1, and the horizontal limit structure can limit the; the positioning pressing seat clamping mechanism is a horizontal telescopic clamping structure as shown in figure 1, and comprises a telescopic assembling and disassemblingarm 23 horizontally arranged on a driving gear support frame, and a top cover assembling and disassemblinghole 16 is further arranged on thepositioning pressing seat 17 corresponding to the telescopic assembling and disassemblingarm 23. When the pressurechamber top cover 14 is disassembled, thedriving gear 22 is controlled to move to enable the telescopic loading and unloadingarm 23 to be aligned with the top cover loading and unloadinghole 16, then the telescopic loading and unloadingarm 23 is controlled to extend out and penetrate into the top cover loading and unloadinghole 16, then thedriving gear 22 is controlled to move to enable the driving gear support frame to be integrally lifted, and then the pressure chamber top cover 14 can be disassembled.

As another embodiment of the pressure chamber top cover dismounting part of the invention, the pressure chamber top cover lifting control mechanism is a hydraulic cylinder structure which is symmetrically arranged relative to the center of the pressure chamber top cover 14 as shown in fig. 2, and comprises a positioning pressure seat lifting hydraulic cylinder, wherein the positioning pressure seat lifting hydraulic cylinder is arranged in a manner that the cylinder bottom end is low and the telescopic end is high in an inclined manner, the cylinder bottom end of the positioning pressure seat lifting hydraulic cylinder is hinged and installed on the integral frame 1, and the positioning pressure seat lifting hydraulic cylinder is connected with thehydraulic pump station 2 through a hydraulic pipeline and a control valve group; the positioning pressing seat clamping mechanism is a bayonet clamping structure as shown in fig. 2, and comprises a clamping fixture block which is hinged to the end part of the telescopic end of the positioning pressing seat lifting hydraulic cylinder, and a limiting clamp ring structure is further arranged on the position, corresponding to the clamping fixture block, of thepositioning pressing seat 17. When dismantling pressurechamber top cap 14, control location pressure seat hydraulic cylinder stretches out and makes centre gripping fixture block joint press the spacing snap ring ofseat 17 in the location structural back, continue control location and press seat hydraulic cylinder to stretch out, because the slope of location pressure seat hydraulic cylinder sets up, therefore location pressure seat hydraulic cylinder keeps on when stretching out centre gripping fixture block atress decomposition be two parts, partly is along the location clamping-force of pressing the radial direction ofseat 17, another part is along thelocation pressure seat 17 axial direction's lift force, can realize pressurechamber top cap 14's dismantlement.

In order to avoid the influence on the dynamic load control precision when the in-situ disturbance excitation control part is loaded, as a further improvement scheme of the invention, the surface of the integral frame 1 is provided with a magnetic shielding wrapping layer, and the magnetic shielding wrapping layer can avoid the phenomenon of reduction of the dynamic load control precision caused by the magnetization effect of an electromagnetic field on the integral frame 1 when the in-situ disturbance excitation control part is loaded.

In order to accurately obtain the quality data of the rock particles discharged by leakage, as a further improvement scheme of the invention, a drying mechanism is also arranged on a solid-liquid separation mechanism of the seepage treatment device 6, namely, the rock particles discharged by leakage are dried by the drying mechanism and then weighed by an electronic scale, so that the accurate obtaining of the quality data of the rock particles discharged by leakage can be realized.

In order to monitor and control the particle loss quality under the condition of the maximum particle diameter and realize the anti-blocking effect, as a further improvement scheme of the present invention, as shown in fig. 4, a replaceable loss particle diameter control net 39 is further arranged above the lowerporous plate 11, and the aperture of the loss particle diameter control net 39 is smaller than that of the porous through holes of the lowerporous plate 11. Through the loss granule particlediameter control net 39 of changing different apertures, can realize controlling the biggest particle diameter that the granule runs off, can realize simultaneously that the stifled effect of preventing ofporous disk 11 down, and then improve the life ofporous disk 11 down.

Because the broken rock mass has obvious heterogeneity, and the heterogeneity of the broken rock mass is further aggravated by the underground multiple rock sample mixed layered arrangement form, so as to facilitate the research on the distribution thicknesses of different types of rock samples and different types of rock samples under the multiple rock sample mixed layered arrangement form and the relationship between different loading pressures and seepage forms, as a further improvement scheme of the invention, the loadinghydraulic cylinder 3 is provided with a main cylinderstate monitoring sensor 26 electrically connected with thedata acquisition module 28. In the test process, the master cylinderstate monitoring sensor 26 feeds back the output pressure data of the loadinghydraulic cylinder 3 to thedata acquisition module 28 in real time, and thecomputer 36 simultaneously feeds back the output pressure data of the loadinghydraulic cylinder 3 according to the master cylinderstate monitoring sensor 26 when constructing the fractured rock fractal dimension model, the seepage path evolution model, the surface crack model and the surface crack opening model.

In order to ensure the stability of the initial pressure of the injected seepage liquid and further obtain more accurate test data, as a further improvement of the invention, the seepage liquid supply control part further comprises a seepagepressure stabilizing device 31, and the output end of the seepageliquid pumping device 30 is communicated and connected with theliquid inlet hole 15 through the seepagepressure stabilizing device 31 and a pipeline.

In order to prevent the unsmooth seepage caused by the arrangement of the upperpermeable plate 10 and the lowerpermeable plate 11, as a further improvement scheme of the invention, as shown in fig. 3, a plurality of annular grooves and radial grooves communicated with the water permeable through holes are respectively arranged on the upper surface and the lower surface of the upperpermeable plate 10 and the upper surface and the lower surface of the lowerpermeable plate 11, the plurality of annular grooves are concentrically arranged, and the annular grooves are communicated with each other through the radial grooves arranged along the radial direction; the bottom end of theliquid inlet hole 15 is set to be a tapered hole structure with a small upper part and a big lower part; the inlet end of the seepage outlet channel 5 is provided with a large-diameter port structure.

The permeability test method of the broken rock mass under the condition of simulated complex disturbance can realize the reduction of the in-situ disturbance load obtained by the mine field test, can accurately simulate the environments of static load, impact load, long-term stable load, periodic pulse and vibration load, actual measurement disturbance load, seepage pressure and the like of the broken rock mass under the condition of complex in-situ disturbance, has high control precision of the disturbance load, high complexity of simulating dynamic load, comprehensive monitoring data, convenient installation and disassembly and high automation degree, and is more accurate compared with the traditional method of only measuring the inlet pressure and the outlet flow; through setting up the distribution thickness of different kinds of rock specimens and different kinds of rock specimens, be convenient for study multiple rock specimen mix response rule and the mechanism of the osmotic pressure gradient of broken rock mass inside under the complicated dynamic load effect under the layering arrangement form, can provide important test platform and more accurate test data for key scientific problems such as research cemented broken rock mass reconsitution water barrier permeability.

Claims (10)

1. A fractured rock permeability test method under the condition of simulated complex disturbance is disclosed, wherein a fractured rock permeability test system comprises an integral frame (1), a pressure chamber part, a pressure loading control part, a permeable liquid supply control part, an in-situ disturbance excitation control part, a visual detection part and a centralized electric control part;

the pressure loading control part is fixedly arranged at the inner bottom of the integral frame (1) and comprises a hydraulic pump station (2) and a loading hydraulic cylinder (3), the loading hydraulic cylinder (3) is vertically and fixedly arranged on the integral frame (1), the telescopic end of the loading hydraulic cylinder (3) is vertically and upwards ejected, and the loading hydraulic cylinder (3) is connected with the hydraulic pump station (2) through a hydraulic pipeline and a control valve group;

the pressure chamber part comprises a pressure chamber (38) arranged in the integral frame (1), and the pressure chamber (38) comprises a pressure chamber base (4), a visual pressure chamber cylinder wall (9) and a pressure chamber top cover (14); a pressure chamber base (4) is coaxially, detachably and fixedly arranged at the top end of a telescopic end of a loading hydraulic cylinder (3) through a pressure chamber base positioning and mounting component, a seepage outlet channel (5) penetrating through the pressure chamber base (4) is arranged in the pressure chamber base (4), the inlet end of the seepage outlet channel (5) is communicated with the top plane of the pressure chamber base (4), the outlet end of the seepage outlet channel (5) is connected with a seepage processing device (6) through an outlet seepage flow sensor, the bottom of a visual pressure chamber cylinder wall (9) is coaxially, hermetically and fixedly arranged on the pressure chamber base (4), the visual pressure chamber cylinder wall (9) and the pressure chamber base (4) jointly form a barrel-shaped structure, a plurality of seepage water pressure sensors (37) are uniformly distributed on the inner wall of the visual pressure chamber cylinder wall (9) from top to bottom, and a cylinder wall side pressure dynamic sensor (12) is further arranged on the inner wall of the visual pressure chamber cylinder wall, the bottom of the inner cavity of the visual pressure chamber cylinder wall (9) is provided with a lower permeable plate (11) of which the outer diameter size is matched with the inner diameter size of the visual pressure chamber cylinder wall (9), and a plurality of permeable through holes communicated with the percolate outlet channel (5) are uniformly distributed on the lower permeable plate (11); the pressure chamber top cover (14) is coaxially arranged at the top of the visual pressure chamber cylinder wall (9), the outer diameter of the pressure chamber top cover (14) is matched with the inner diameter of the visual pressure chamber cylinder wall (9), a liquid inlet hole (15) penetrating through the pressure chamber top cover (14) is formed in the pressure chamber top cover (14), an orifice injection pressure sensor (25) is arranged at the orifice position of the liquid inlet hole (15), an upper water permeable plate (10) with the outer diameter matched with the inner diameter of the visual pressure chamber cylinder wall (9) is fixedly arranged at the bottom of the pressure chamber top cover (14), and a plurality of water permeable through holes communicated with the liquid inlet hole (15) are uniformly distributed in the upper water permeable plate (10); the seepage treatment device (6) comprises a solid-liquid separation mechanism, and an electronic scale for weighing the discharged sample rock particles is arranged on the solid-liquid separation mechanism;

the seepage liquid supply control part comprises a seepage liquid pumping device (30) and a seepage pumping electric control device (32) electrically connected with the seepage liquid pumping device (30), the input end of the seepage liquid pumping device (30) is connected with a seepage liquid supply box (29) through a pipeline, and the output end of the seepage liquid pumping device (30) is communicated and connected with the liquid inlet hole (15) through a pipeline;

the in-situ disturbance excitation control part comprises a disturbance signal execution device and a disturbance signal excitation electric control device (35); the disturbance signal execution device comprises a positioning pressure head (21) and a positioning pressure seat (17), the positioning pressure seat (17) is coaxially and fixedly arranged at the top of the pressure chamber top cover (14), the position of the positioning pressure head (21) corresponding to the positioning pressure seat (17) is vertically arranged on the integral frame (1), a positioning pressure head lifting structure is arranged on the positioning pressure head (21), the bottom of the positioning pressure head (21) and the top of the positioning pressure seat (17) are of spherical structures which are arranged in a matched mode, an alternating current excitation coil (20) is arranged on the positioning pressure head (21), a direct current excitation coil is arranged on the positioning pressure seat (17), and an in-situ disturbance dynamic pressure sensor (19) is further arranged on the positioning pressure head (21) or the positioning pressure seat (17); the disturbance signal excitation electric control device (35) comprises a controllable alternating current excitation module (34) and a direct current power supply module (33), the controllable alternating current excitation module (34) is electrically connected with the alternating current excitation coil (20), and the direct current power supply module (33) is electrically connected with the direct current excitation coil;

the visual detection part comprises a digital image collector (27), and the digital image collector (27) is positioned, erected and installed corresponding to the wall (9) of the visual pressure chamber;

the centralized electric control part comprises a computer (36), a data acquisition module (28), a pressure loading control loop, a liquid injection control loop, an in-situ disturbance excitation control loop, a visual detection control loop and a data analysis and calculation loop, wherein the computer (36) is respectively and electrically connected with the hydraulic pump station (2), the seepage pumping electric control device (32), the disturbance signal excitation electric control device (35) and the data acquisition module (28), and the data acquisition module (28) is respectively and electrically connected with electronic scales of a seepage water pressure sensor (37), an orifice liquid injection pressure sensor (25), an outlet seepage flow sensor, a cylinder wall side pressure dynamic sensor (12), an in-situ disturbance dynamic pressure sensor (19), a digital image collector (27) and a seepage processing device (6);

the method is characterized by comprising the following steps:

a. preparation of the test: the method comprises the steps that a crushed rock mass sample is placed into a pressure chamber (38) and then additionally provided with a pressure chamber top cover (14) provided with a positioning pressure seat (17), after a lifting structure on the positioning pressure head (21) is adjusted to enable the positioning pressure head (21) to move upwards and move backwards, the pressure chamber (38) is integrally sent into an integral frame (1), a pressure chamber base (4) is coaxially positioned and installed at the top end of a telescopic end of a loading hydraulic cylinder (3) through a positioning structure on the top surface of the telescopic end of the loading hydraulic cylinder (3) and a pressure chamber base positioning installation component, and a lifting structure on the positioning pressure head (21) is adjusted again to enable the positioning pressure head (21) to descend and be connected with a water pipeline and an electric pipeline after being close to the positioning pressure;

b. the test process comprises the following steps: the computer (36) controls the hydraulic pump station (2) to work through the pressure loading control loop so that the loading hydraulic cylinder (3) jacks up and inputs pressure load to the broken rock mass sample in the pressure chamber (38), meanwhile, the computer (36) controls the seepage pumping electric control device (32) to work through the liquid injection control loop so that seepage liquid is injected into the broken rock mass sample in the pressure chamber (38) through the liquid inlet hole (15), and the computer (36) controls the digital image collector (27) to work through the visual detection control loop; the osmotic water pressure sensor (37) feeds back the water pressure data of the seepage fluid flowing through the osmotic water pressure sensor (37) in the pressure chamber (38) to the data acquisition module (28) in real time, and the computer (36) calculates and establishes a water pressure distribution model of the osmotic pressure of the osmotic water in the pressure chamber (38) along the loading direction according to the data of the osmotic water pressure sensor (37) acquired by the data acquisition module (28) and a built-in program; a digital image collector (27) sends image data of a broken rock sample observed through a visual pressure chamber cylinder wall (9) to a data collection module (28) according to a set time interval, an in-situ disturbance dynamic pressure sensor (19) feeds back pressure data borne by a pressure chamber top cover (14) to the data collection module (28) in real time, an orifice injection pressure sensor (25) feeds back initial pressure data of injected seepage liquid to the data collection module (28) in real time, an outlet seepage flow sensor feeds back discharged seepage liquid pressure data to the data collection module (28) in real time, a cylinder wall side pressure dynamic sensor (12) feeds back confining pressure data of the visual pressure chamber cylinder wall (9) to the broken rock sample to the data collection module (28) in real time, and an electronic scale of a seepage processing device (6) feeds back quality data of the leaked and discharged rock particles to the data collection module (28), the computer (36) firstly carries out error analysis calculation and mean value output on the image data of the digital image collector (27) collected by the data collection module (28), the pressure data born by the pressure chamber top cover (14), the initial pressure data of the injected seepage liquid, the pressure data of the discharged seepage liquid, the confining pressure data and the quality data of the discharged rock particles respectively, and then constructs a fractal dimension model, a seepage path evolution model, a surface crack model and a surface crack opening model of the fractured rock according to a built-in gray image fractal dimension analysis program, a seepage path digital reconstruction program and a fractured rock surface crack statistical program;

when a static load test is carried out, the computer (36) controls the loading hydraulic cylinder (3) to output a stable rated static load, and the condition that the crushed rock body bears a long-term stable load is simulated;

when a static load and preset dynamic load test is carried out, the computer (36) is provided with characteristic data of static load size, loading speed, dynamic load form, period, amplitude, peak value size, cycle times and superposition mode, then the computer (36) controls the loading hydraulic cylinder (3) to output stable rated static load, the computer (36) controls a disturbance signal to excite an electric control device (35) to work through an in-situ disturbance excitation control loop to enable a direct current excitation coil and an alternating current excitation coil (20) to generate magnetic flux, electromagnetic force is generated between a positioning pressure head (21) and a positioning pressure seat (17) to enable the positioning pressure head (21) and the positioning pressure seat (17) to generate relative excitation disturbance, and the conditions of bearing the preset form of periodic disturbance load and the superposition action of impact load when a crushed rock body bears long-term stable load are simulated;

when a static load + in-situ disturbance load test or a modified in-situ disturbance load test is carried out, the size and the loading speed of the static load are set in a computer (36), then an in-situ disturbance signal measured on site is led into the computer (36), and then intervention conditions of in-situ disturbance are set in the computer (36), or the in-situ disturbance signal is manually modified firstly and then the intervention conditions of the modified in-situ disturbance are set; then the computer (36) controls the loading hydraulic cylinder (3) to output a stable rated static load, the computer (36) monitors the static load loading state, when the static load loading condition reaches a set in-situ disturbance intervention condition, the computer (36) controls a disturbance signal excitation electric control device (35) to work through an in-situ disturbance excitation control loop to enable the direct current excitation coil and the alternating current excitation coil (20) to generate magnetic flux, electromagnetic force is generated between the positioning pressure head (21) and the positioning pressure seat (17) to enable the positioning pressure head (21) and the positioning pressure seat (17) to generate relative excitation to realize in-situ disturbance or modified in-situ disturbance, and the condition that the crushed rock body bears the in-situ disturbance load or the modified in-situ disturbance load while bearing the static load is simulated.

2. The permeability test method of the fractured rock mass under the condition of the simulated complex disturbance according to claim 1, wherein the bottom of the visual pressure chamber cylinder wall (9) of the fractured rock mass permeability test system is detachably and fixedly arranged on the pressure chamber base (4); the broken rock mass permeability test system also comprises a pressure chamber top cover dismounting part, wherein the pressure chamber top cover dismounting part comprises a pressure chamber top cover lifting control mechanism arranged on the integral frame (1) and a positioning pressure seat clamping mechanism arranged on the pressure chamber top cover lifting control mechanism, the positioning pressure seat clamping mechanism is used for clamping and positioning a positioning pressure seat (17) when the pressure chamber top cover (14) is dismounted after the test is finished, the pressure chamber top cover lifting control mechanism is used for lifting and lowering the positioning pressure seat (17) when the pressure chamber top cover (14) is dismounted after the test is finished, and the pressure chamber top cover lifting control mechanism and the positioning pressure seat clamping mechanism are respectively electrically connected with the computer (36);

after the step b is completed, when the pressure chamber top cover (14) is disassembled, the positioning pressure seat (17) is lifted by controlling the actions of the pressure chamber top cover lifting control mechanism and the positioning pressure seat clamping mechanism to separate the pressure chamber top cover (14) from the compact integrated structure broken rock sample, after the pressure chamber top cover (14) is disassembled and the pressure chamber (38) is moved out of the integral frame (1), the visual pressure chamber cylinder wall (9) is separated from the compact integrated structure broken rock sample by injecting water into the pressure chamber (38) and disassembling the visual pressure chamber cylinder wall (9).

3. The permeability test method of the fractured rock mass under the condition of the simulated complex disturbance according to claim 2, wherein the pressure chamber roof lifting control mechanism is a gear rack structure which is arranged in central symmetry relative to the pressure chamber roof (14) and comprises a rack guide rail (24) and a driving gear (22), the rack guide rail (24) is vertically and fixedly installed on the integral frame (1), the driving gear (22) with a driving motor is arranged on the rack guide rail (24) in a meshing and matching manner, the driving gear (22) is installed on the integral frame (1) in a sliding and matching manner in the vertical direction through a driving gear support frame, and a horizontal limiting structure which can limit the driving gear support frame from being separated from the integral frame (1) is arranged between the driving gear support frame and the integral frame (1); the positioning pressing seat clamping mechanism is a horizontal telescopic clamping structure and comprises a telescopic loading and unloading arm (23) horizontally arranged on the driving gear supporting frame, and a top cover loading and unloading hole (16) is also formed in the position, corresponding to the telescopic loading and unloading arm (23), of the positioning pressing seat (17);

when the pressure chamber top cover (14) is disassembled, the driving gear (22) is controlled to act to enable the telescopic loading and unloading arm (23) to be aligned with the top cover loading and unloading hole (16), then the telescopic loading and unloading arm (23) is controlled to extend out and penetrate into the top cover loading and unloading hole (16), and then the driving gear (22) is controlled to act to enable the driving gear supporting frame to be lifted integrally, so that the pressure chamber top cover (14) is disassembled.

4. The permeability test method of the fractured rock mass under the simulated complex disturbance condition according to claim 2, wherein the pressure chamber top cover lifting control mechanism is a hydraulic cylinder structure which is arranged in a central symmetry way relative to the pressure chamber top cover (14) and comprises a positioning pressure seat lifting hydraulic cylinder, the positioning pressure seat lifting hydraulic cylinder is arranged in a manner that the cylinder bottom end is low and the telescopic end is high in inclination, the cylinder bottom end of the positioning pressure seat lifting hydraulic cylinder is hinged and installed on the integral frame (1), and the positioning pressure seat lifting hydraulic cylinder is connected with the hydraulic pump station (2) through a hydraulic pipeline and a control valve group; the positioning pressing seat clamping mechanism is a bayonet clamping structure and comprises a clamping fixture block which is hinged to the end part of the telescopic end of the positioning pressing seat lifting hydraulic cylinder, and a limiting clamp ring structure is further arranged on the positioning pressing seat (17) at a position corresponding to the clamping fixture block;

when dismantling pressure chamber top cap (14), control location is pressed a hydraulic cylinder and is stretched out and make centre gripping fixture block joint press the spacing snap ring of seat (17) at the location structural back, continue control location and press a hydraulic cylinder to stretch out, location is pressed a hydraulic cylinder and is continued when stretching out centre gripping fixture block atress and decompose into two parts, partly is along the location clamping-force of pressing seat (17) radial direction, another part is along the location and presses seat (17) axial direction's lift force, realize the dismantlement of pressure chamber top cap (14).

5. The permeability test method of the fractured rock mass under the condition of the simulated complex disturbance according to any one of claims 1 to 4, wherein a drying mechanism is further arranged on a solid-liquid separation mechanism of a seepage treatment device (6) of the fractured rock mass permeability test system;

and b, after the rock mass sample to be crushed is compacted into an integral structure and the discharged seepage pressure data is not fed back by the outlet seepage flow sensor any more, starting the drying mechanism to set time to remove moisture from the leaked and discharged rock particles, and then starting the electronic scale to weigh so as to accurately obtain the quality data of the leaked and discharged rock particles.

6. The permeability test method of the fractured rock mass under the condition of the simulated complex disturbance according to any one of claims 1 to 4, wherein a replaceable loss particle size control net (39) is further arranged above the lower permeable plate (11) of the fractured rock mass permeability test system, and the aperture of the loss particle size control net (39) is smaller than that of the water permeable through holes of the lower permeable plate (11);

in the step a, before the crushed rock mass sample is placed in the pressure chamber (38), the maximum particle size of particle loss is controlled by replacing the loss particle size control net (39) with different pore diameters.

7. The permeability test method of the fractured rock mass under the condition of the simulated complex disturbance according to any one of claims 1 to 4, wherein a master cylinder state monitoring sensor (26) electrically connected with a data acquisition module (28) is arranged on a loading hydraulic cylinder (3) of the fractured rock mass permeability test system;

in the step b, the master cylinder state monitoring sensor (26) feeds back the output pressure data of the loading hydraulic cylinder (3) to the data acquisition module (28) in real time, and the computer (36) simultaneously feeds back the output pressure data of the loading hydraulic cylinder (3) according to the master cylinder state monitoring sensor (26) when constructing the fractured rock fractal dimension model, the seepage path evolution model, the surface crack model and the surface crack opening model.

8. The permeability test method for fractured rock mass under the condition of simulatable complex disturbance according to any one of claims 1 to 4, wherein the pressure chamber (38) is integrally conveyed into the integral frame (1) in the step a by means of hoisting.

9. The permeability test method for fractured rock mass under the condition of simulatable complex disturbance according to any one of claims 1 to 4, wherein the pressure chamber (38) is integrally conveyed into the integral frame (1) in the step a by means of translation conveying.

10. The method for testing the permeability of the fractured rock mass under the simulatable complex disturbance condition according to any one of claims 1 to 4, wherein when a static load + in-situ disturbance load or a modified in-situ disturbance load test is performed in the step b, the artificial modification of the in-situ disturbance signal comprises adjusting the peak value of the in-situ disturbance signal to simulate an extreme condition, and adjusting a superposition period load or an impact load to simulate the superposition influence of various disturbance factors.

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