CN105527211B - The method of testing of the lower tight rock permeability of resultant stress strain - Google Patents
The method of testing of the lower tight rock permeability of resultant stress strain Download PDFInfo
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- CN105527211B CN105527211B CN201510987864.1A CN201510987864A CN105527211B CN 105527211 B CN105527211 B CN 105527211B CN 201510987864 A CN201510987864 A CN 201510987864A CN 105527211 B CN105527211 B CN 105527211B
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- 239000011435 rock Substances 0.000 title claims abstract description 93
- 230000035699 permeability Effects 0.000 title claims abstract description 56
- 238000010998 test method Methods 0.000 title 1
- 238000000034 method Methods 0.000 claims abstract description 50
- 230000008859 change Effects 0.000 claims abstract description 43
- 238000012360 testing method Methods 0.000 claims abstract description 25
- 230000003204 osmotic effect Effects 0.000 claims abstract description 20
- 238000011068 loading method Methods 0.000 claims abstract description 17
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052742 iron Inorganic materials 0.000 claims abstract description 4
- 230000000704 physical effect Effects 0.000 claims abstract description 4
- 230000008569 process Effects 0.000 claims description 31
- 230000009471 action Effects 0.000 claims description 7
- 230000006641 stabilisation Effects 0.000 claims description 4
- 238000011105 stabilization Methods 0.000 claims description 4
- 230000000903 blocking effect Effects 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 50
- 230000006378 damage Effects 0.000 description 9
- 238000005259 measurement Methods 0.000 description 4
- 238000000518 rheometry Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 239000003921 oil Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 230000008595 infiltration Effects 0.000 description 2
- 238000001764 infiltration Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- 238000004904 shortening Methods 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
- G01N15/082—Investigating permeability by forcing a fluid through a sample
- G01N15/0826—Investigating permeability by forcing a fluid through a sample and measuring fluid flow rate, i.e. permeation rate or pressure change
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- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
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Abstract
The present invention relates to the method for testing that a kind of resultant stress strains lower tight rock permeability, comprise the following steps：Air accumulator and gas cylinder are sequentially connected in balancing gate pit gas circuit upper end, gas circuit lower end connecting valve, first pressure table and second pressure gauge are set respectively in gas circuit upper end, lower end；Air-locked iron block is positioned in balancing gate pit, calibration system；Measure the physical property of rock sample to be measured；The rock sample is positioned in balancing gate pit and applies confined pressure；Open gas cylinder and be continuously applied osmotic pressure, after steady air current, close valve, the curve that record first pressure table and the numerical value of second pressure gauge change over time respectively, stop recording after linear change occurs for curve, open valve；Biased, biased per one-level after applying by balancing gate pit's multistage loadings, the method walked in repetition, record the curve that first pressure table and the reading of second pressure gauge change over time under biass at different levels respectively；Choose corresponding linearity range to carry out curve fitting, calculate the permeability for surveying rock sample.
Description
Technical Field
The invention relates to a method for testing permeability, in particular to a method for testing permeability of low-permeability rock under full stress strain, and belongs to the fields of rock engineering, low-permeability gas reservoirs and mineral exploitation.
Background
In recent years, petroleum strategic reserve engineering is emerging in China, which can cope with short-term petroleum supply impact on one hand, and can serve national energy safety on the other hand to guarantee continuous supply of crude oil. The reserves of shale gas in China exceed the reserves of conventional natural gas, and the development of the unconventional energy sources has important significance for promoting economic development and protecting the environment. Oil gas is stored in an underground water-sealed cave depot, the exploitation of shale gas also relates to low-permeability rocks, and the permeability of the low-permeability rocks is one of important parameters for exploration, development and stability evaluation of rock engineering such as the storage of the oil gas and the exploitation of the shale gas. In the actual excavation and oil gas exploitation processes of the cave depot, rocks are in a complex stress state. Therefore, the permeability under the bias stress environment which meets the actual engineering needs to be measured.
The existing low-permeability rock permeability measuring method mainly adopts a steady state method and a pulse method, and mainly has the following problems:
most of low-permeability rocks are deformed and brittle failure under the action of partial stress, the partial stress falls down instantly after reaching a peak value, and the existing equipment is difficult to measure the permeability of the rocks in the failure process and after failure; moreover, most devices adopt manual recording, and the measurement precision is not high.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide a method for testing the permeability of low-permeability rock under full stress strain.
The technical scheme is as follows: the invention relates to a method for testing the permeability of low-permeability rocks under full stress strain, which comprises the following steps:
(1) the upper end of an air passage of the pressure chamber is sequentially connected with an air storage tank and an air bottle, the lower end of the air passage is connected with a valve for communicating or blocking the atmospheric pressure, then a first pressure gauge is arranged between the air storage tank and the pressure chamber, a second pressure gauge is arranged between the valve and the pressure chamber, and the first pressure gauge and the second pressure gauge are connected with a computer;
(2) opening a valve, placing an airtight iron block in a pressure chamber, and calibrating a system;
(3) measuring physical properties of the rock sample to be measured;
(4) placing the rock sample in a pressure chamber to apply confining pressure to a test set value and keeping the confining pressure constant;
(5) opening the gas cylinder to continuously apply osmotic pressure, closing the valve after the gas flow is stable, closing the gas cylinder, respectively recording the time-varying curves of the numerical values of the first pressure gauge and the second pressure gauge, stopping recording after the curves are linearly varied, and opening the valve;
(6) maintaining osmotic pressure, loading bias voltage to the rock sample step by step until the rock sample is destroyed, recording the change curves of axial strain and annular strain of the rock sample in the process, closing the valve after the gas flow is stable after each level of bias voltage is applied, recording the curves of the numerical values of the first pressure gauge and the second pressure gauge along with the change of time under the bias voltage, stopping recording after the curves linearly change, and opening the valve;
(7) and selecting a corresponding linear section from the acquired numerical value change curves of the first pressure gauge and the second pressure gauge, fitting, and calculating the permeability of the measured rock sample.
By loading the bias voltage step by step until the rock sample is destroyed, maintaining the osmotic pressure, recording the change curves of the pressures at the upper end and the lower end of the air passage of the pressure chamber along with the time in real time in the test process, selecting corresponding linear sections for fitting the obtained curves, and accurately obtaining the permeability change of the low-permeability rock in the whole stress strain process, including the permeability in the destruction process and after the destruction.
In the step (6), when the circumferential strain of the rock sample to be tested starts to obviously deviate from linear increase under the action of bias voltage, the bias voltage loading level is reduced, and meanwhile, the gas flow stabilization time is shortened. When each level of bias voltage is loaded, the degree of annular deformation generally shows more stable linear increase along with the change of time, when the change obviously deviates from the linearity, the rock sample begins to yield under the bias voltage of the level, the permeability of the rock sample is increased more, at the moment, the occurrence of rheology can be slowed down by reducing the bias voltage loading level and shortening the gas flow stabilizing time, and the permeability change in the strain process is recorded more comprehensively.
The rock sample to be tested continuously generates annular deformation, when the rock sample to be tested is close to damage under the action of bias voltage until the rock sample is damaged, the bias voltage is continuously loaded, the valve is rapidly opened and closed, and the first pressure gauge and the second pressure gauge are continuously recorded. At the moment, the rock sample is rapidly deformed, the permeability is rapidly increased, the occurrence of rheology is avoided by not providing stable time, the valve is rapidly opened and closed for many times under the condition of continuously loading bias voltage, the change curve in the process of opening and closing for many times is uninterruptedly recorded, and when the final data is processed, a linear section is selected for piecewise fitting, so that the peak stress and the permeability after damage can be obtained.
Specifically, during the above process, when the axial strain is suddenly changed, the valve is rapidly opened and rapidly closed. When the axial strain curve is suddenly changed from stable linear increase to non-linear, the instantaneous deformation of the rock sample is larger, the valve is quickly opened and closed at the moment, and the pressure change of the first pressure gauge and the second pressure gauge in the period is recorded.
In the step (6), in the process of applying the bias voltage, the seepage pressure at the upper end of the gas path is kept by opening and closing the gas cylinder. After the loading osmose is accomplished, the upper end of the gas circuit keeps stable osmose, and in the process of loading bias voltage, the change of the osmose is known by observing the reading of the first pressure gauge after the gas flow is stable, and when the osmose is reduced, the gas cylinder is opened until the osmose is recovered, and the gas cylinder is closed.
In the step (7), the formula for calculating the permeability of the low-permeability rock is as follows:
wherein,
in the formula: k is the permeability of the rock sample measured, mugIs the viscosity of the gas in the cylinder, h and A are the height and cross-sectional area of the rock sample to be measured, P0At atmospheric pressure, Δ t is the time difference between the time periods corresponding to the selected linear segments, Q is the steady flow rate of the gas in the time period, PuIs the reading of the first pressure gauge over the time period, Δ P is the pressure difference of the second pressure gauge over the time period, VdThe total volume of the lower end of the gas path of the rock sample measured during calibration of the system.
During the test, the computer automatically records the change of the readings of the two pressure gauges along with the time. The osmotic pressure is kept in the test process, namely the change of the value of the first pressure gauge is small, the effective value of the second pressure gauge is changed linearly, a linear section is selected for fitting, the starting time and the ending time of the linear section are determined, and the corresponding P is obtaineduDelta P is a fixed value, and if the selected time periods are different, P isuAnd the value of delta P is changed along with the change of the value of delta P, so that the permeability of the rock sample under the stress strain corresponding to the linear section is determined.
Has the advantages that: compared with the prior art, the invention has the remarkable advantages that:
(1) the invention provides a new method for testing the permeability of low-permeability rocks, wherein bias voltage is applied step by step in the testing process, the time-varying curves of the pressures at the upper end and the lower end of the gas circuit under the bias voltage of each stage are recorded, then the permeability is determined by adopting a curve fitting mode, the permeability variation in the full stress strain process of the low-permeability rocks can be measured, meanwhile, more effective test data can be obtained by step-by-step recording and the starting and stopping time of the data record is controlled by opening and closing a valve at the lower end of the gas circuit, more data points can be recorded as far as possible, and a proper time period is selected for fitting, so that the measurement precision in the whole process is improved;
(2) according to the method, after the rock sample is yielded and the rock sample is near to be damaged and then damaged, the permeability near the peak value stress and after the damage is obtained by controlling the bias loading and the airflow stabilizing time, and the situation that the permeability at the critical time cannot be measured and calculated due to the fact that the bias stress falls down instantly after reaching the peak value is avoided;
(3) the invention connects the pressure gauge with the computer, records the curve change process in real time through the computer, and obviously improves the measurement precision.
Drawings
FIG. 1 is a schematic view of the apparatus for testing permeability of low permeability rock under full stress strain according to the present invention;
FIG. 2 is a schematic diagram of the pressure chamber of FIG. 1;
FIG. 3 is a graph showing axial strain, hoop strain, volume strain and permeability change of a rock in a full stress-strain process measured by the method;
FIG. 4 is a graph showing the corresponding linear segments selected in step (7) of the present invention after fitting.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings.
The invention relates to a method for testing the permeability of low-permeability rocks under full stress strain, which comprises the following steps:
(1) as shown in fig. 1, an air storage tank 2 and an air bottle 3 are sequentially connected to the upper end of an air passage of a pressure chamber 1 through a guide pipe, the lower end of the air passage is connected with a valve 4 for communicating or blocking air through a guide pipe, then a first pressure gauge 5 is arranged between the air storage tank 2 and the pressure chamber 1 at the upper end of the air passage, a second pressure gauge 6 is arranged between the valve 4 and the pressure chamber 1 at the lower end of the air passage, and the first pressure gauge 5 and the second pressure gauge 6 are connected with a computer 7, for example, the computer 7 can be connected through a; the gas in the gas cylinder can be inert gas such as argon and the like, and the gas viscosity is mug；
(2) Opening a valve, placing an airtight iron block in the pressure chamber 1, and calibrating the system;
respectively measuring the total volume V of the conduit at the upper end of the gas circuit and the gas storage tank 2uAnd the total volume V of the conduit at the lower end of the gas circuit and the second pressure gauge 6d；
(3) Measuring physical properties of the rock sample to be measured; including the height h and cross-sectional area A of the rock sample;
(4) as shown in fig. 2, the rock sample is placed in a pressure chamber, and confining pressure is applied to a test set value through a confining pressure loading device 8 and is kept constant;
(5) opening the gas cylinder to continuously apply osmotic pressure, closing the valve after the gas flow is stable, closing the gas cylinder, respectively recording the time-varying curves of the numerical values of the first pressure gauge and the second pressure gauge, stopping recording after the curves are linearly varied, and opening the valve; as shown in fig. 3, a curve d is a change curve of the permeability of the rock sample under the full stress strain, wherein a point a in the graph indicates that the circumferential strain curve starts to obviously deviate from the linear increase, and a point B indicates that the axial strain is suddenly changed.
Open the gas cylinder and exert the osmotic pressure to the rock specimen, the numerical value of first manometer can constantly take place the shake, a period of time back, the air flow is stable, the numerical value of first manometer tends to steadily, close the valve, this moment, the gas circuit upper end forms stable osmotic pressure, the numerical value of first manometer lasts and is in steady state, the pressure of gas circuit lower extreme is the atmospheric pressure initially, along with the infiltration of gaseous in the rock specimen, the numerical value of second manometer on the gas circuit is linear increase along with the time variation, when the curve takes place linear variation, explain the seepage flow is invariable, accord with Darcy's law, stop the record this moment, open the valve, get rid of the gas that the infiltration got into the gas circuit lower extreme, make the pressure of gas circuit lower extreme be the atmospheric.
(6) Maintaining the osmotic pressure, loading bias voltage to the rock sample step by step through a bias voltage loading device 9 until the rock sample is damaged as shown in figure 2, and recording the change curve of the axial strain and the circumferential strain of the rock sample in the process as shown in figure 3, wherein a curve a is the circumferential strain curve of the rock sample, a curve b is the axial strain curve of the rock sample, and a curve c is the volume strain curve of the rock sample; after each stage of bias voltage is applied, closing the valve when the air flow is stable, recording the curve of the numerical values of the first pressure gauge and the second pressure gauge along with the change of time under the bias voltage, stopping recording after the curve is linearly changed, and opening the valve;
when the circumferential strain of the rock sample to be tested starts to obviously deviate from the linear increase under the action of the bias voltage (namely, at the position A in the curve a in the graph 3), the bias voltage loading level is reduced, and meanwhile, the air flow stabilization time is shortened. When each level of bias voltage is loaded, the numerical value of the hoop strain generally shows relatively stable linear increase along with the time change, when the numerical value change obviously deviates from the linearity, the rock sample begins to yield under the level of bias voltage, relatively large hoop deformation is generated, the permeability of the rock sample is relatively increased, at the moment, the occurrence of rheology can be slowed down by shortening the stabilization time, and the permeability change in the strain process is recorded more comprehensively.
The rock sample to be tested continuously generates annular deformation, when the rock sample to be tested is close to damage under the action of bias voltage until the rock sample is damaged, the bias voltage is continuously loaded, the valve is rapidly opened and closed, and the first pressure gauge and the second pressure gauge are continuously recorded. At the moment, the rock sample is rapidly deformed, the permeability is rapidly increased, the bias voltage is continuously loaded, the occurrence of rheology is avoided by rapidly opening and closing the valve for many times and providing no stable time, the whole change curve in the process is uninterruptedly recorded, and when the final data is processed, the linear section in the process is selected for piecewise fitting, so that the peak stress and the permeability after damage can be obtained.
During the process from near to failure of the rock sample, in the event of a sudden change in axial strain (i.e. at B in curve B in figure 3), the valve opens rapidly and closes rapidly. When the axial strain curve is suddenly changed from stable linear increase to non-linear, the instantaneous deformation of the rock sample is larger, the valve is quickly opened and closed at the moment, and the pressure change of the first pressure gauge and the second pressure gauge in the period is recorded.
In this step, in the process of applying bias voltage, the osmotic pressure at the upper end of the gas path is maintained by opening and closing the gas cylinder. After the loading osmotic pressure is completed, the upper end of the gas circuit is kept at a stable osmotic pressure, after the loading is biased, the osmotic pressure gas flow shakes, after the gas flow is stable, the change of the osmotic pressure is known by observing the reading of the first pressure gauge, when the reading is lower than the osmotic pressure value kept in the step (5), the gas cylinder is opened to apply the osmotic pressure, and the gas cylinder is closed until the osmotic pressure is recovered.
(7) And selecting a corresponding linear section from the acquired numerical value change curves of the first pressure gauge and the second pressure gauge, fitting, and calculating the permeability of the measured rock sample.
During the test, the computer automatically records the change of the readings of the two pressure gauges along with the time.
The hoop strain, axial strain, and volume strain curves of the rock sample in fig. 3 can reflect the full stress-strain process of the rock sample. Therefore, the offset pressure value of the rock sample in a certain state can be determined according to the circumferential strain, the axial strain and the volume strain curve, so that a corresponding linear change section is selected under the offset pressure, and the permeability of the rock sample in the state is measured and calculated after curve fitting.
Specifically, because the osmotic pressure is kept in the test process, after the air flow is stable, the first pressure gaugeThe value of the second pressure gauge is stable after the initial fluctuation, the valve is closed to start recording until the curve is linearly changed, the value in the period is an effective value, the effective value is linearly changed along with the time, therefore, when the permeability of each stress strain stage is measured and calculated, a linear section is selected, the starting time and the ending time of the linear section are determined, the time difference delta t of the time section is obtained, and the reading P of the first pressure gauge in the time section can be found outuAnd (3) fitting a numerical value change curve of the first pressure gauge and the second pressure gauge corresponding to the selected linear section as shown in fig. 4.
Measuring the total volume V of the conduit at the lower end of the gas path and the second pressure gauge measured in the step (2)dSubstituting the value into the following formula (1), and calculating the stable air flow rate Q of the time period; then the viscosity mu of the gas in the gas cylindergAtmospheric pressure P0And (3) substituting the values of the height h and the cross-sectional area A of the rock sample measured in the step (3) into the following formula (2), and calculating to obtain the permeability K of the measured rock sample in the linear section.
QΔt(P0+ΔP/2)＝VdΔP (1)
Selecting different linear segments, PuThe value of Δ P will also change, and the permeability of the low permeability rock at full stress strain can be measured. The curve d in fig. 3 is the permeability change curve of the measured rock sample under the full stress strain.
According to the invention, different pressure gauges are respectively adopted at the upper end and the lower end of the air passage of the pressure chamber to record the data of the pressure change along with the time in the test process in real time by using a computer, the permeability is determined by adopting a curve fitting mode, the starting and stopping time of the data record is determined by controlling the opening and closing of the valve at the downstream end, and the permeability change of the low-permeability rock in the whole stress strain process, including the permeability in the damage process and after the damage, can be measured; meanwhile, the change process of the curve is recorded in real time through a computer, and the measurement precision is obviously improved.
Claims (5)
1. A method for testing the permeability of low-permeability rock under full stress strain is characterized by comprising the following steps:
(1) the upper end of an air passage of the pressure chamber is sequentially connected with an air storage tank and an air bottle, the lower end of the air passage is connected with a valve for communicating or blocking the atmospheric pressure, then a first pressure gauge is arranged between the air storage tank and the pressure chamber, a second pressure gauge is arranged between the valve and the pressure chamber, and the first pressure gauge and the second pressure gauge are connected with a computer;
(2) opening a valve, placing an airtight iron block in a pressure chamber, and calibrating a system;
(3) measuring physical properties of the rock sample to be measured;
(4) placing the rock sample in a pressure chamber to apply confining pressure to a test set value and keeping the confining pressure constant;
(5) opening the gas cylinder to continuously apply osmotic pressure, closing the valve after the gas flow is stable, closing the gas cylinder, respectively recording the time-varying curves of the numerical values of the first pressure gauge and the second pressure gauge, stopping recording after the curves are linearly varied, and opening the valve;
(6) maintaining osmotic pressure, loading bias voltage to the rock sample step by step until the rock sample is destroyed, recording the change curves of axial strain and annular strain of the rock sample in the process, closing the valve after the gas flow is stable after each level of bias voltage is applied, recording the curves of the numerical values of the first pressure gauge and the second pressure gauge along with the change of time under the bias voltage, stopping recording after the curves linearly change, and opening the valve; when the circumferential strain of the rock sample to be tested begins to obviously deviate from linear increase under the action of bias voltage, the bias voltage loading level is reduced, and meanwhile, the gas flow stabilization time is shortened;
(7) and selecting a corresponding linear section from the acquired numerical value change curves of the first pressure gauge and the second pressure gauge, fitting, and calculating the permeability of the measured rock sample.
2. The method for testing the permeability of the low-permeability rock under the full stress strain of claim 1, wherein when the rock sample to be tested is about to be damaged and is damaged under the action of bias voltage, the bias voltage is continuously loaded, the valve is rapidly opened and closed, and the first pressure gauge and the second pressure gauge are continuously recorded.
3. The method for testing low permeability rock permeability under full stress strain of claim 2, wherein the valve is rapidly opened and closed when the axial strain curve is suddenly changed.
4. The method for testing the permeability of low-permeability rocks under full stress strain according to claim 1, wherein in the step (6), the permeability at the upper end of the gas path is maintained by opening and closing the gas cylinder during the process of applying the bias voltage.
5. The method for testing the permeability of low-permeability rocks under full stress strain according to claim 1, wherein in the step (7), the formula for calculating the permeability of low-permeability rocks is as follows:
<mrow> <mi>K</mi> <mo>=</mo> <mfrac> <mrow> <mn>2</mn> <msub> <mi>Q&mu;</mi> <mi>g</mi> </msub> <mi>h</mi> </mrow> <mi>A</mi> </mfrac> <mfrac> <msub> <mi>P</mi> <mn>0</mn> </msub> <mrow> <mo>(</mo> <msubsup> <mi>P</mi> <mi>u</mi> <mn>2</mn> </msubsup> <mo>-</mo> <msubsup> <mi>P</mi> <mn>0</mn> <mn>2</mn> </msubsup> <mo>)</mo> </mrow> </mfrac> <mo>;</mo> </mrow>
wherein,
in the formula:
k is the permeability of the rock sample to be measured,
μgis the viscosity of the gas in the gas cylinder,
h and A are the height and cross-sectional area of the measured rock sample respectively,
P0the pressure is the atmospheric pressure,
at is the time difference of the time segments corresponding to the selected linear segment,
q is the steady flow rate of the gas for this period,
Puis the reading of the first pressure gauge over the time period,
ap is the pressure difference of the second pressure gauge over the time period,
Vdfor system calibrationAnd (5) measuring the total volume of the lower end of the rock sample gas path.
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| CN110031376B (en) * | 2019-04-17 | 2020-09-11 | 中南大学 | Rock gas permeability testing method under multistage rheological loading |
| CN111707531A (en) * | 2020-06-19 | 2020-09-25 | 河海大学 | Test method for complex seepage stress coupling loading path |
| CN114199739B (en) * | 2021-11-25 | 2024-03-29 | 中铁二十局集团第四工程有限公司 | CO in rock chemical corrosion environment 2 Triaxial seepage test system and method |
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| CN103207137A (en) * | 2013-04-08 | 2013-07-17 | 河海大学 | Device for fully automatically measuring penetration rate and void ratio of compact rock under dynamic confining pressure |
| CN103207138B (en) * | 2013-04-08 | 2015-06-24 | 河海大学 | Method for combined measurement of permeability and porosity of dense rock under dynamic confining pressure |
| CN104034644B (en) * | 2014-06-11 | 2016-06-08 | 河海大学 | A kind of can the heterogeneous percolating medium triaxial stress seepage flow coupling test device of Quick Measurement porosity |
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