CN111982692B - A long-term deformation test method of rock under different stress components and its application - Google Patents

A long-term deformation test method of rock under different stress components and its application Download PDF

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CN111982692B
CN111982692B CN202010854011.1A CN202010854011A CN111982692B CN 111982692 B CN111982692 B CN 111982692B CN 202010854011 A CN202010854011 A CN 202010854011A CN 111982692 B CN111982692 B CN 111982692B
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CN111982692A (en
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郑虹
闫生存
陈涛
袁鹏
李萌
徐怀胜
刘畅
柳秀洋
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Wuhan Institute of Rock and Soil Mechanics of CAS
Sichuan Huaneng Luding Hydropower Co Ltd
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Sichuan Huaneng Luding Hydropower Co Ltd
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    • G—PHYSICS
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    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G01N3/10—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
    • G01N3/12—Pressure testing
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0001—Type of application of the stress
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
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    • G01—MEASURING; TESTING
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    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058—Kind of property studied
    • G01N2203/0069—Fatigue, creep, strain-stress relations or elastic constants
    • G01N2203/0071—Creep
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    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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Abstract

本发明公开了一种岩石在不同应力分量下的长期变形测试方法，属于岩石力学性质测试范畴。该方法利用不同电机伺服泵分别加载和维持试验岩样的围压、轴压以及孔隙水压力，实现三轴应力和孔隙水压力条件下的恒内压与恒外压加载模式，同时定位围压电机伺服泵内活塞位置记录泵内油量体积，通过轴向压头横截面积和轴向位移消除轴向加载过程中活塞位移耗损三轴室内油量体积对试验岩样体积变形测量造成的误差，利用泵内油量体积变化数据得到试验岩样在恒内压与恒外压条件下的体积应变数据，结合轴向变形数据，通过公式计算分别得到球应力分量和偏应力分量两种应力状态的下体积应变和偏应变随时间的关系。本发明还公布了所述长期变形测试方法的应用。

Figure 202010854011

The invention discloses a long-term deformation testing method of rock under different stress components, which belongs to the testing category of rock mechanical properties. This method uses different motor servo pumps to load and maintain the confining pressure, axial pressure and pore water pressure of the test rock sample respectively, and realizes the constant internal pressure and constant external pressure loading mode under the condition of triaxial stress and pore water pressure, and locates the confining pressure at the same time. The position of the piston in the motor servo pump records the oil volume in the pump, and the piston displacement loss during the axial loading process is eliminated by the cross-sectional area of the axial indenter and the axial displacement. Error, using the volume change data of the oil volume in the pump to obtain the volumetric strain data of the test rock sample under the conditions of constant internal pressure and constant external pressure, combined with the axial deformation data, the spherical stress component and the deviatoric stress component are obtained by formula calculation respectively. Volumetric strain and deviatorial strain versus time for the state. The invention also discloses the application of the long-term deformation testing method.

Figure 202010854011

Description

Long-term deformation testing method for rock under different stress components and application thereof
Technical Field
The invention relates to a long-term deformation testing method of a rock under different stress components, and belongs to the field of rock mechanical property testing. The method is mainly used for researching the evolution rule of the volume strain and the partial strain of the surrounding rock along with time in two stress component states of a spherical stress component and a partial stress component, analyzing the long-term stability of the rock engineering and predicting the aging deformation of the rock engineering.
Background
Rock long-term deformation has been a direction of great concern in the field of rock mechanics. With the popularization of deep underground engineering in China, the long-term stability and safety of rock engineering are the most important of the engineering. Many underground construction rock masses undergo significant deformation over time during operational and even construction periods. The softer rock is shown as an obvious large deformation phenomenon, the harder rock is shown as gradually cracking from inside to outside along with the time, and finally generating larger displacement and even damage on the surface, for the reservoir rock with a pore structure, the reservoir rock shows the continuous change of compaction and expansion deformation along with the time under the combined action of external load and internal water pressure, and the continuous surface uplifting or collapse is reflected to the ground.
Mechanically, the phenomenon of long-term deformation of the rock is also called creep. Many scholars at home and abroad study the creep characteristics of the rock under different conditions by developing rock rheological mechanical property experiments and constitutive models. The long-term deformation rule of the rock is the key for researching the long-term stability and safety of rock engineering. In a traditional creep model, viscous deformation is generally considered to be caused by partial stress, deformation caused by ball stress only does not have time dependence, however, the rock serving as a natural material has a pore structure or microcracks (fissures), and the change of external load or the change of underground water conditions under engineering conditions can cause the change of the pore structure or the initiation, extension, opening and closing of the fissures. The natural defects of rock materials and the accumulated damage under different working conditions cause the rock volume deformation to change along with time, so that the rock material shows different creep characteristics under different stress components: exhibits volume creep under ball stress; exhibiting shear creep under the action of an offset stress.
At present, the long-term deformation test method of rock under different conditions is studied, for example, chinese patent publication no: 110346218A publication date: 2019.10.18 invention relates to a rock creep test method based on different mining stress paths, which considers the actual change situation of the stress environment after deep coal resource mining and adopts the way of increasing the axial pressure and discharging the confining pressure to perform creep testAnd (6) testing, and respectively obtaining axial displacement and transverse displacement through an axial sensor and a circumferential sensor. The patent does not consider the time dependence of volume deformation, and the annular sensor needs to apply enough pressure to clamp the outer layer of the rubber sleeve of the rock sample, so that the long-term deformation of the thermoplastic sleeve or the rubber sleeve caused by local extrusion of the obtained deformation data cannot be eliminated, the testing accuracy is not high enough, and particularly, the long-term deformation monitoring error of harder rock is large. Moreover, such a circumferential sensor can only acquire a local deformation, which is not equivalent to the full-height deformation of the sample measured by an axial sensor, and the radial deformation measured by the sensor is not representative. Therefore, the circumferential deformation data also needs to take account of the heterogeneous deformation characteristic of the rock to obtain the full-height circumferential deformation data of the rock sample. Direct measurement of the volumetric deformation of a rock sample is key to solving this problem. In the aspect of rock long-term volume deformation measurement, Chinese patent publication No.: 111272562A publication date: 2020.06.12 entitled device and method for measuring rock high temperature creep volume deformation, provides a method for monitoring and calculating creep volume deformation by using a magnetostrictive liquid level meter. The method needs to switch gas and liquid modes for loading confining pressure for many times so as to ensure the range of measuring range, the process is complicated and difficult to operate, and the axial pressure loading process has certain influence on maintaining the constancy of the confining pressure. The deformation measurement precision is less than 0.1mm3And the requirement of high-precision measurement under the condition of small deformation of hard rock cannot be met. In addition, the invention patent does not consider the influence of the internal pore water pressure of the rock sample on the volume deformation. Therefore, the device cannot test the volume deformation data of the rock sample under the conditions of constant internal pressure and constant external pressure, and further cannot obtain the relation between the volume strain and the offset strain of the rock under two stress states of a spherical stress component and an offset stress component in the environment of constant internal pressure and constant external pressure along with time.
Disclosure of Invention
The invention aims to solve the technical problem that the conventional rock creep testing device cannot test the volume deformation data of a rock sample under the conditions of constant internal pressure and constant external pressure for a long time, and provides a long-term deformation testing method of a rock under different stress components. Loading and maintaining confining pressure and axis of test rock sample respectively through different motor servo pumpsAnd the pressure and the pore water pressure realize a constant internal pressure and constant external pressure loading mode under the conditions of triaxial stress and the pore water pressure. Considering that the creep loading mode is a constant confining pressure state, the confining pressure motor servo pump is proposed to adopt a motor servo pump which is manufactured by French TOP industrie and is of model number PMHP50-1000, the piston position in the confining pressure motor servo pump can be simultaneously positioned to record the volume of oil in the pump, and the scale is accurate to 10-3mm3. In the testing process, the volume of the oil quantity in the pump recorded by the servo pump of the confining pressure motor not only comprises the volume change of the oil quantity caused by the volume deformation of the rock sample, but also comprises the volume change of the oil quantity in the triaxial chamber caused by the displacement of the piston of the upper pressure head. In order to obtain accurate volume deformation data of the test rock sample under the conditions of constant internal pressure and constant external pressure, the error caused by the volume of oil in a triaxial chamber consumed by piston displacement in the axial loading process on the volume deformation measurement of the test rock sample can be eliminated through the cross section area and the axial displacement of the axial pressure head. And finally, calculating the relationship of the lower volume strain and the offset strain of the two stress states of the spherical stress component and the offset stress component along with time by combining the axial deformation data through a formula.
In order to achieve the purpose, the technical scheme and the test method adopted by the invention are carried out according to the following steps:
a. the method comprises the following steps of (1) loading a cylindrical rock sample with the diameter of H and the height of D into a sealing sleeve, placing permeation gaskets on the upper end surface and the lower end surface of the cylindrical rock sample, fixing the sealing sleeve between a pressure head and a base in a triaxial chamber, and uniformly installing at least two LVDTs between the pressure head and the base around the periphery of the sealing sleeve, so that the LVDTs can acquire axial deformation data in the loading process of the cylindrical rock sample, namely the displacement of a piston on the upper part of the pressure head;
b. after the pressure head and the base are tightly combined up and down, oil and air are pumped out from the three-axis chamber by using a vacuum pump, the vacuum degree is kept, the three-axis chamber is filled with oil, and a first motor servo pump capable of filling oil into the three-axis chamber is filled with oil;
c. filling oil into a bias chamber which applies pressure to the upper end of a piston at the upper part of the pressure head, and filling oil into a second motor servo pump which can fill oil into the bias chamber;
d. enabling a third motor servo pump which can fill water to the upper end face and the lower end face of the cylindrical rock sample from the pressure head and the base to be full of water;
e. the first motor servo pump is used for filling oil to the three-axis chamber, and the confining pressure is loaded to a set value sigma3Keeping the constant, and recording the oil volume corresponding to the position of the piston in the first motor servo pump;
f. filling water to the upper end face and the lower end face of the cylindrical rock sample through a third motor servo pump, loading the pore pressure p to a set value and maintaining the pore pressure p constant;
g. charging oil into the bias chamber via a second motor servo pump, loading the bias force (σ)1-σ3) Axial pressure σ1The compression strength of the cylindrical rock sample is 50-80% and is kept constant;
h. acquiring axial deformation initial data L of cylindrical rock sample0And initial oil volume V in the servo pump of the first motor0；
Acquiring axial deformation data L of cylindrical rock sample at i-moment to t-momenttAnd the current oil volume V in the servo pump of the first motort
Rock sample long-term axial strain epsilon at time t1And volume strain εvRespectively as follows:
ε1＝(Lt-L0)/H
Figure BDA0002645759540000031
wherein D ispistonThe diameter of the piston at the upper part of the pressure head,
Figure BDA0002645759540000032
the oil drainage loss value caused by the movement of the piston on the upper part of the pressure head.
According to the definition of the strain component, obtaining the axial offset strain e1Comprises the following steps:
e1＝ε1-εv/3
plotting the volume strain epsilon of a cylindrical rock samplevTime dependence and axial offset strain e1A time-dependent curve is obtainedAnd (3) long-term deformation rule of the rock sample under different stress components.
Further, the scale of the first motor servo pump is accurate to 10-3mm3And the volume data of the oil in the pump can be read through the position of the piston in the pump.
Preferably, an oil filling pipe in the inner wall of the triaxial chamber is respectively communicated with the vacuum pump and the oil tank through a first three-way valve, wherein when the first three-way valve is closed, the oil filling pipe is communicated with the vacuum pump to form a vacuum pumping loop; when the first three-way valve is opened, the oil filling pipe is communicated with the oil tank to form a downstream oil filling loop.
Preferably, a pressurized oil pipe in the upper end of the three-shaft chamber is communicated with an oil tank through a first valve, a first motor servo pump and a second valve in sequence to form a confining pressure loading loop.
Preferably, the biasing chamber is communicated with the oil tank through a third valve, a second motor servo pump and a fourth valve in sequence to form a biasing loading loop.
Preferably, the permeation channels of the pressure head and the base are respectively communicated with a second three-way valve and a third motor servo pump, the second three-way valve is also respectively communicated with a fifth valve and a third motor servo pump, the fifth valve is also communicated with a water tank, the second three-way valve is closed, and when the fifth valve is opened, the water tank is communicated with the third motor servo pump; and when the second three-way valve is opened and the fifth valve is closed, the permeation channels of the pressure head and the base are respectively communicated with the third motor servo pump to form a pore pressure loading loop.
The long-term deformation testing method of the rock under different stress components is applied to the long-term stability analysis and the aging deformation prediction of rock engineering: and respectively obtaining creep model parameters of the spherical stress component and the offset stress component according to evolution curves of the lower volume strain and the axial offset strain of the cylindrical rock sample in two stress states of the spherical stress component and the axial offset stress component along with time, and applying the creep model parameters to long-term stability analysis and aging deformation prediction of rock mass engineering.
The application of the invention comprises the following specific steps:
1) according to the initial volume strain and the initial axial partial strain in the evolution curve of the volume strain and the axial partial strain, the axial pressure loaded in the step g, the confining pressure loaded in the step e and the pore pressure loaded in the step f at the initial moment are brought into an initial equation of a creep model, and elastic parameters are obtained: bulk and shear moduli;
2) according to N groups of volume strain data at the starting moment on an evolution curve of the volume strain along with time and a volume strain calculation value obtained by model calculation, a creep model parameter under a spherical stress component in a model is taken as an unknown parameter, and a creep model parameter under the spherical stress component is obtained by using a target function and a least square method;
3) and according to N groups of axial partial strain data at the starting moment on the evolution curve of the axial partial strain along with the time and an axial partial strain calculation value obtained by model calculation, taking a creep model parameter under a partial stress component in the model as an unknown parameter, and solving a creep model parameter under the partial stress component by using a target function and a least square method.
Due to the adoption of the technical scheme, the invention has the following advantages and positive effects:
(1) the method provides a new method for long-term deformation measurement of the rock under different stress components, and can automatically acquire rock sample volume deformation data simply, conveniently and accurately, wherein the volume data is accurate to 10-3mm3. And expressing the error of the volume loss of the oil in the triaxial chamber caused by the displacement of the piston in the axial loading process on the volume deformation measurement of the test rock sample by the product of the cross section area of the axial pressure head and the axial displacement.
(2) The stress condition of the rock sample also considers the water pressure effect in the pore space besides the confining pressure and the axial pressure.
(3) According to the definition of the strain component, the evolution curves of the volume strain and the partial strain of the rock sample in two stress states of the spherical stress component and the partial stress component along with time are obtained by combining the axial deformation data.
Drawings
FIG. 1 is a schematic representation of the test method of the present invention;
FIG. 2 is an axial strain ε obtained by a test method of the present invention1An evolution curve;
FIG. 3 is a diagram of the testing method of the present inventionSystem of volume strain epsilonvAn evolution curve;
FIG. 4 is an axial offset strain e plotted by the test method of the present invention1A plot of time;
Detailed Description
The invention is further described below in conjunction with specific implementations and computational methods.
Sandstone with porosity of about 21.5% is used as a case object, a sandstone creep test is carried out under the conditions of confining pressure, axial pressure and pore water pressure, and volume strain epsilon of a sample under a ball stress component is obtainedvTime dependence and axial offset strain e under offset stress component1The test method is carried out according to the following steps of the relation curve along with time:
a, a standard cylindrical rock sample with the diameter D of 49.70mm and the height H of 100.02mm is loaded into a sealing sleeve 18, permeation gaskets are respectively arranged on the upper end surface and the lower end surface of the sealing sleeve 18, the sealing sleeve 18 is fixed between a pressure head 1 and a base 2 in a triaxial chamber 19, two LVDTs (linear variable differential transformers) 3 are arranged between the pressure head 1 and the base 2, axial deformation data in the loading process of the standard cylindrical rock sample are collected, and the data also reflect the displacement of a piston 4 on the upper portion of the pressure head;
b, after the installation is finished, lifting the base 2 of the three-axis chamber 19, closing the three-axis chamber 19 up and down tightly, closing the first three-way valve 5, communicating the three-axis chamber 19 with the vacuum pump 6, starting the vacuum pump 6 to exhaust oil and air in the three-axis chamber 19, opening the first three-way valve 5, opening the first valve 7 and the second valve 8, connecting the three-axis chamber 19 with the first motor servo pump 9 and the oil tank 10, filling oil into the three-axis chamber 19, closing the first valve 7 after the oil is filled, filling oil into the first motor servo pump 9, and closing the second valve 8 after the oil is filled;
c, opening the third valve 11 and the fourth valve 12, connecting the bias chamber 20 with the second motor servo pump 13 and the oil tank 10, filling oil into the bias chamber 20, closing the third valve 11 after the bias chamber is filled with the oil, filling the second motor servo pump 13 with the oil, and closing the fourth valve 12 after the bias chamber is filled with the oil;
d, closing the second three-way valve 14, opening the fifth valve 15, connecting the third motor servo pump 16 with the water tank 17, and filling the third motor servo pump 16 with water;
e opening the first valve 7, starting the first motor servo pump 9, loading the confining pressure to the set value sigma3Recording the oil volume corresponding to the position of a piston in the first motor servo pump 9 when the pressure is 6MPa and is kept constant; the motor servo pump mentioned in the embodiment is suggested to adopt a motor servo pump which is produced by TOP industrie of France and has the model number of PMHP 50-1000;
f, closing the fifth valve 15, opening the second three-way valve 14, starting the third motor servo pump 16, and loading the pore pressure to a set value p of 1MPa and keeping the pore pressure constant;
g opening the third valve 11, starting the second motor-driven servo pump 13, and applying a biasing force (σ)1-σ3) At 18MPa and held constant, i.e. axial pressure σ1＝24MPa；
h at the moment, the data acquisition instrument automatically acquires axial deformation initial data L0And the initial volume V of oil in the first motor servo pump 90
The i data acquisition instrument automatically acquires axial deformation data L of 160 hourstAnd the current volume V of oil in the first motor servo pump 9t
The long-term axial strain epsilon of the rock sample is obtained1And volume strain εvRespectively as follows:
ε1＝(Lt-L0) The formula is
Figure BDA0002645759540000061
Wherein H is the height of the standard cylindrical rock sample of 100.02mm,
d is the diameter of a standard cylindrical rock sample of 49.70mm,
Dpistonthe diameter of the piston at the upper part of the pressure head is 50mm,
Figure BDA0002645759540000062
the oil drainage loss value caused by the movement of the pressure head piston.
As shown in FIG. 3, the axial strain ε is plotted1And volume strain εvAn evolution curve over time;
from the definition of the strain component, the axial offset strain e is obtained as shown in FIG. 41Comprises the following steps:
e1＝ε1-εv/3
thereby drawing axial offset strain e1Curve over time:
the long-term deformation rule of the rock sample under different stress components is obtained. Based on the curves of the volume strain and the partial strain of the rock along with time in two stress states of the spherical stress component and the partial stress component, the mechanical parameters suitable for the creep model can be obtained, and the method is applied to long-term stability analysis and aging deformation prediction of rock engineering. According to the three-dimensional constitutive relation of a viscoelastic part under a ball stress state, the three-dimensional constitutive relation is as follows:
Figure BDA0002645759540000071
wherein σm，
Figure BDA0002645759540000072
Mean stress and its first and second derivatives, εv，
Figure BDA0002645759540000073
Respectively the volume strain and its first and second derivatives, KM、KK、
Figure BDA0002645759540000074
All are ball stress viscoelasticity parameters.
The three-dimensional constitutive relation of the viscoelastic part in the biased stress state can be expressed as:
Figure BDA0002645759540000075
wherein S isij，
Figure BDA0002645759540000076
The partial stress tensor and its first and second derivatives, eij，
Figure BDA0002645759540000077
The partial strain tensor and its first and second derivatives, G, respectivelyM、GK、
Figure BDA0002645759540000078
All are bias stress viscoelasticity parameters.
Thus, the σ in the experiment1，σ3Constitutive equation under the condition of p constant:
Figure BDA0002645759540000079
Figure BDA0002645759540000081
wherein σ1Axial pressure, σ, applied for step g3Confining pressure applied in step e, and pore pressure applied in step f, σm＝(σ1+2σ3)/3. According to the initial equation at the time when t is 0:
Figure BDA0002645759540000082
the axial strain epsilon of the measured data1And volume strain εvSubstituting the initial equation of the creep model to obtain an elastic parameter: bulk modulus KMAnd shear modulus GM。
N groups (N) of start time on the evolution curve of the volume strain with time>3) Measured data epsilonvAnd calculating the value
Figure BDA0002645759540000083
With KK，
Figure BDA0002645759540000084
As unknown parameters, using the objective function:
Figure BDA0002645759540000085
least square method for obtaining creep model parameter K under spherical stress componentK，
Figure BDA0002645759540000086
Wherein the volume is measured by a strain calculation
Figure BDA0002645759540000087
The following equation is obtained:
Figure BDA0002645759540000088
similarly, according to N groups (N) of the initial time on the evolution curve of the axial partial strain along with the time>3) Measured data e1And calculating the value
Figure BDA0002645759540000089
With GK、
Figure BDA00026457595400000810
As unknown parameters, using the objective function:
Figure BDA00026457595400000811
least square method for obtaining creep model parameter G under partial stress componentK、
Figure BDA00026457595400000812
Wherein the axial offset strain is calculated
Figure BDA0002645759540000091
The following equation is obtained:
Figure BDA0002645759540000092
and obtaining creep model parameters in numerical calculation.

Claims (7)

1.一种岩石在不同应力分量下的长期变形测试方法，其特征在于，该测试方法按以下步骤进行：1. a long-term deformation test method of rock under different stress components, is characterized in that, this test method is carried out according to the following steps: a.将直径为H，高度为D的圆柱岩石试样装入密封套管内，圆柱岩石试样上下端面均放置渗透垫片，将密封套管固定于三轴室（19）内的压头（1）与底座（2）之间，围绕密封套管四周在压头（1）与底座（2）之间均匀安装至少两个LVDT（3），使LVDT（3）能采集圆柱岩石试样加载过程中的轴向变形数据，即压头上部活塞（4）的位移量，LVDT为线性可变差动变压器；a. Put a cylindrical rock sample with a diameter of H and a height of D into the sealing casing, place permeable gaskets on the upper and lower ends of the cylindrical rock sample, and fix the sealing casing on the pressure head ( 1) Install at least two LVDTs (3) evenly between the indenter (1) and the base (2) around the sealing sleeve and between the base (2), so that the LVDTs (3) can collect cylindrical rock samples for loading The axial deformation data in the process, that is, the displacement of the upper piston (4) of the indenter, LVDT is a linear variable differential transformer; b.使压头（1）与底座（2）上下合紧后，利用真空泵（6）从三轴室（19）抽出油和空气，并保持真空度，再使三轴室（19）充满油，使能向三轴室（19）充油的第一电机伺服泵（9）充满油；b. After the pressure head (1) and the base (2) are tightly closed up and down, use the vacuum pump (6) to extract oil and air from the triaxial chamber (19), keep the vacuum degree, and then fill the triaxial chamber (19) with oil , so that the first motor servo pump (9) capable of filling the triaxial chamber (19) with oil is filled with oil; c.使向压头上部活塞（4）上端施压的偏压室（20）充满油，使能向偏压室（20）充油的第二电机伺服泵（13）充满油；c. Fill the bias chamber (20) pressing the upper end of the upper piston (4) of the pressure head with oil, and fill the second motor servo pump (13) which can fill the bias chamber (20) with oil; d.使能从压头（1）及底座（2）向圆柱岩石试样上下端面充水的第三电机伺服泵（16）充满水；d. Fill the third motor servo pump (16) with water from the pressure head (1) and the base (2) to the upper and lower end faces of the cylindrical rock sample; e.通过第一电机伺服泵（9）向三轴室（19）充油，加载围压到设定值
Figure 911515DEST_PATH_IMAGE001
并维持恒定，记录 第一电机伺服泵（9）泵内活塞位置对应的油量容积； e. Fill the triaxial chamber (19) with oil through the first motor servo pump (9), and load the confining pressure to the set value
Figure 911515DEST_PATH_IMAGE001
And keep it constant, record the oil volume and volume corresponding to the piston position in the first motor servo pump (9) pump; f.通过第三电机伺服泵（16）向圆柱岩石试样上下端面充水，加载孔隙压力p到设定值并维持恒定；f. Fill the upper and lower end faces of the cylindrical rock sample with water through the third motor servo pump (16), load the pore pressure p to the set value and keep it constant; g.通过第二电机伺服泵（13）向偏压室（20）充油，加载偏压力为
Figure 723613DEST_PATH_IMAGE002
，待轴压
Figure 615214DEST_PATH_IMAGE003
达 到所述圆柱岩石试样抗压强度的50~80%并维持恒定； g. The bias chamber (20) is filled with oil through the second motor servo pump (13), and the loading bias force is
Figure 723613DEST_PATH_IMAGE002
, to be axially pressed
Figure 615214DEST_PATH_IMAGE003
Reach 50-80% of the compressive strength of the cylindrical rock sample and keep it constant; h.采集圆柱岩石试样轴向变形初始数据
Figure 829158DEST_PATH_IMAGE004
和第一电机伺服泵（9）内初始油量体积
Figure 265956DEST_PATH_IMAGE005
； h. Collect initial data of axial deformation of cylindrical rock sample
Figure 829158DEST_PATH_IMAGE004
and the initial oil volume in the first motor servo pump (9)
Figure 265956DEST_PATH_IMAGE005
; i 待t时刻采集圆柱岩石试样轴向变形数据
Figure 814617DEST_PATH_IMAGE006
和第一电机伺服泵（9）内当前油量体积
Figure 995063DEST_PATH_IMAGE007
i Collect the axial deformation data of the cylindrical rock sample at time t
Figure 814617DEST_PATH_IMAGE006
and the current volume of oil in the first motor servo pump (9)
Figure 995063DEST_PATH_IMAGE007
 t时刻岩石试样长期轴向应变
Figure 63513DEST_PATH_IMAGE008
和体积应变
Figure 484979DEST_PATH_IMAGE009
分别为： Long-term axial strain of rock sample at time t
Figure 63513DEST_PATH_IMAGE008
and volumetric strain
Figure 484979DEST_PATH_IMAGE009
They are:
Figure 271669DEST_PATH_IMAGE010
Figure 271669DEST_PATH_IMAGE010
Figure 990226DEST_PATH_IMAGE011
Figure 990226DEST_PATH_IMAGE011
 其中，
Figure 428030DEST_PATH_IMAGE012
为压头上部活塞的直径， in,
Figure 428030DEST_PATH_IMAGE012
is the diameter of the upper piston of the indenter,
Figure 206630DEST_PATH_IMAGE013
为压头上部活塞移动引起的排油量耗损值；
Figure 206630DEST_PATH_IMAGE013
is the oil displacement loss value caused by the movement of the piston on the upper part of the pressure head; 根据应变分量定义，得到轴向偏应变为：According to the definition of the strain component, the axial deflection strain is obtained as:
Figure 480616DEST_PATH_IMAGE014
Figure 480616DEST_PATH_IMAGE014
 绘出圆柱岩石试样体积应变
Figure 986553DEST_PATH_IMAGE009
随时间的关系曲线以及轴向偏应变
Figure 295175DEST_PATH_IMAGE015
随时间的关系 曲线，即得到了岩石试样在不同应力分量下的长期变形规律。 Plot the volumetric strain of a cylindrical rock sample
Figure 986553DEST_PATH_IMAGE009
Time vs. Axial Deviatoric Strain
Figure 295175DEST_PATH_IMAGE015
The relationship curve with time, that is, the long-term deformation law of the rock sample under different stress components is obtained. 2.如权利要求1所述的岩石在不同应力分量下的长期变形测试方法，其特征在于：所述的第一电机伺服泵（9）的刻度精确到10-3mm3且能通过泵内活塞位置读取泵内油量体积数据。2. The long-term deformation test method of rock under different stress components as claimed in claim 1, characterized in that: the scale of the first motor servo pump ( 9 ) is accurate to 10-3 mm and can pass through the pump The position of the piston reads the volume of oil in the pump. 3.如权利要求1所述的岩石在不同应力分量下的长期变形测试方法，其特征在于：所述三轴室（19）内壁中的充油管（22）通过第一三向阀门（5）分别与真空泵（6）和油箱（10）连通，其中第一三向阀门（5）关闭时，充油管（22）与真空泵（6）连通，形成抽真空回路；第一三向阀门（5）打开时，充油管（22）与油箱（10）连通，形成下游充油回路。3. The long-term deformation test method of rock under different stress components according to claim 1, characterized in that: the oil filling pipe (22) in the inner wall of the triaxial chamber (19) passes through the first three-way valve (5) They are respectively connected with the vacuum pump (6) and the oil tank (10), wherein when the first three-way valve (5) is closed, the oil filling pipe (22) is connected with the vacuum pump (6) to form a vacuum pumping circuit; the first three-way valve (5) When opened, the oil filling pipe (22) communicates with the oil tank (10) to form a downstream oil filling circuit. 4.如权利要求1所述的岩石在不同应力分量下的长期变形测试方法，其特征在于：所述三轴室（19）上端中的加压油管依次通过第一阀门（7）、第一电机伺服泵（9）、第二阀门（8）连通油箱（10），形成围压加载回路。4. The long-term deformation test method of rock under different stress components according to claim 1, characterized in that: the pressurized oil pipe in the upper end of the triaxial chamber (19) passes through the first valve (7), the first The motor servo pump (9) and the second valve (8) are connected to the oil tank (10) to form a confining pressure loading circuit. 5.如权利要求1所述的岩石在不同应力分量下的长期变形测试方法，其特征在于：所述偏压室（20）依次通过第三阀门（11）、第二电机伺服泵（13）、第四阀门（12）连通油箱（10），形成偏压加载回路。5. The long-term deformation test method of rock under different stress components according to claim 1, characterized in that: the bias chamber (20) passes through the third valve (11) and the second motor servo pump (13) in sequence and the fourth valve (12) communicates with the oil tank (10) to form a bias loading circuit. 6.如权利要求1所述的岩石在不同应力分量下的长期变形测试方法，其特征在于：所述压头（1）及底座（2）的渗透通道（23）分别连通第二三向阀门（14）和第三电机伺服泵（16），第二三向阀门（14）还分别连通第五阀门（15）和第三电机伺服泵（16），第五阀门（15）还连通水箱（17），所述第二三向阀门（14）关闭，第五阀门（15）打开时，水箱（17）连通第三电机伺服泵（16）；所述第二三向阀门（14）打开，第五阀门（15）关闭时，压头（1）及底座（2）的渗透通道（23）分别连通第三电机伺服泵（16），形成孔隙压力加载回路。6 . The long-term deformation testing method of rock under different stress components according to claim 1 , characterized in that: the infiltration channels ( 23 ) of the pressure head ( 1 ) and the base ( 2 ) are respectively connected to the second three-way valve. 7 . (14) and the third motor servo pump (16), the second three-way valve (14) is also connected to the fifth valve (15) and the third motor servo pump (16) respectively, and the fifth valve (15) is also connected to the water tank ( 17), the second three-way valve (14) is closed, and when the fifth valve (15) is opened, the water tank (17) is connected to the third motor servo pump (16); the second three-way valve (14) is opened, When the fifth valve (15) is closed, the permeation channels (23) of the pressure head (1) and the base (2) are respectively connected to the third motor servo pump (16) to form a pore pressure loading circuit. 7.基于权利要求1所述的岩石在不同应力分量下的长期变形测试方法在岩体工程长期稳定性分析与时效变形预测的应用，其特征在于：根据圆柱岩石试样在球应力分量和偏应力分量两种应力状态的下体积应变和偏应变随时间的演化曲线分别获得球应力分量和偏应力分量的蠕变模型参数，应用于岩体工程长期稳定性分析与时效变形预测；7. The application of the long-term deformation test method of rock under different stress components based on claim 1 in the long-term stability analysis and aging deformation prediction of rock mass engineering, it is characterized in that: according to the cylindrical rock sample, the spherical stress component and the partial pressure are measured. The evolution curves of volumetric strain and deviatoric strain with time under the two stress states of the stress component respectively obtain the creep model parameters of the spherical stress component and the deviatoric stress component, which are applied to the long-term stability analysis and aging deformation prediction of rock mass engineering; 具体包括以下步骤：Specifically include the following steps: 1）根据体积应变和轴向偏应变演化曲线中初始体积应变
Figure 979097DEST_PATH_IMAGE016
和初始轴向偏应变
Figure 724068DEST_PATH_IMAGE017
，将初 始时刻步骤g加载的轴压
Figure 50007DEST_PATH_IMAGE018
、步骤e加载的围压
Figure 947556DEST_PATH_IMAGE019
、步骤f加载的孔隙压力p带入蠕变模型 的初始方程，求得弹性参数：体积模量
Figure 317226DEST_PATH_IMAGE020
和剪切模量
Figure 565805DEST_PATH_IMAGE021
； 1) According to the initial volumetric strain in the evolution curve of volumetric strain and axial deviatoric strain
Figure 979097DEST_PATH_IMAGE016
and the initial axial deviatoric strain
Figure 724068DEST_PATH_IMAGE017
, the axial pressure loaded in step g at the initial moment
Figure 50007DEST_PATH_IMAGE018
, the confining pressure loaded in step e
Figure 947556DEST_PATH_IMAGE019
, The pore pressure p loaded in step f is brought into the initial equation of the creep model, and the elastic parameters are obtained: bulk modulus
Figure 317226DEST_PATH_IMAGE020
and shear modulus
Figure 565805DEST_PATH_IMAGE021
; 其中，t=0时刻的初始方程为：Among them, the initial equation at time t=0 is:
Figure 164276DEST_PATH_IMAGE022
；其中，
Figure 431179DEST_PATH_IMAGE023
为平均应力；
Figure 164276DEST_PATH_IMAGE022
;in,
Figure 431179DEST_PATH_IMAGE023
is the mean stress; 2）根据体积应变随时间的演化曲线上开始时刻的N组体积应变数据
Figure 722483DEST_PATH_IMAGE025
和模型计算得到 的体积应变计算值
Figure 192778DEST_PATH_IMAGE026
，以模型中球应力分量下的蠕变模型参数
Figure 109787DEST_PATH_IMAGE027
，
Figure 716349DEST_PATH_IMAGE028
，
Figure 178555DEST_PATH_IMAGE029
作为未知参数， 利用目标函数和最小二乘法求得球应力分量下蠕变模型参数
Figure 385414DEST_PATH_IMAGE027
，
Figure 591267DEST_PATH_IMAGE028
，
Figure 317915DEST_PATH_IMAGE029
； 2) N groups of volumetric strain data at the starting time on the evolution curve of volumetric strain with time
Figure 722483DEST_PATH_IMAGE025
and the calculated volumetric strain calculated by the model
Figure 192778DEST_PATH_IMAGE026
, as the creep model parameters under the spherical stress component in the model
Figure 109787DEST_PATH_IMAGE027
,
Figure 716349DEST_PATH_IMAGE028
,
Figure 178555DEST_PATH_IMAGE029
As the unknown parameters, the parameters of the creep model under the spherical stress component are obtained by using the objective function and the least square method
Figure 385414DEST_PATH_IMAGE027
,
Figure 591267DEST_PATH_IMAGE028
,
Figure 317915DEST_PATH_IMAGE029
; 其中目标函数为：
Figure 206149DEST_PATH_IMAGE030
，N>3； The objective function is:
Figure 206149DEST_PATH_IMAGE030
, N>3; 其中体积应变计算值
Figure 385457DEST_PATH_IMAGE026
由下式求得： The calculated value of volumetric strain
Figure 385457DEST_PATH_IMAGE026
It is obtained by the following formula:
Figure 395001DEST_PATH_IMAGE031
；
Figure 395001DEST_PATH_IMAGE031
; 3）根据轴向偏应变随时间的演化曲线上开始时刻的N组轴向偏应变数据
Figure 491002DEST_PATH_IMAGE032
和模型计算 得到的轴向偏应变计算值
Figure 685223DEST_PATH_IMAGE033
，以模型中偏应力分量下的蠕变模型参数
Figure 617407DEST_PATH_IMAGE034
，
Figure 148751DEST_PATH_IMAGE035
，
Figure 115570DEST_PATH_IMAGE036
作为未知 参数，利用目标函数和最小二乘法求得偏应力分量下蠕变模型参数
Figure 90480DEST_PATH_IMAGE034
，
Figure 509960DEST_PATH_IMAGE035
，
Figure 844995DEST_PATH_IMAGE036
； 3) N groups of axial deviatoric strain data at the starting time on the evolution curve of axial deviatoric strain with time
Figure 491002DEST_PATH_IMAGE032
and the calculated value of axial deviatoric strain calculated by the model
Figure 685223DEST_PATH_IMAGE033
, as the creep model parameters under the deviatoric stress component in the model
Figure 617407DEST_PATH_IMAGE034
,
Figure 148751DEST_PATH_IMAGE035
,
Figure 115570DEST_PATH_IMAGE036
As the unknown parameters, the parameters of the creep model under the deviatoric stress component are obtained by using the objective function and the least square method
Figure 90480DEST_PATH_IMAGE034
,
Figure 509960DEST_PATH_IMAGE035
,
Figure 844995DEST_PATH_IMAGE036
; 其中目标函数为：
Figure 400741DEST_PATH_IMAGE037
，N>3； The objective function is:
Figure 400741DEST_PATH_IMAGE037
, N>3; 其中轴向偏应变计算值
Figure 812131DEST_PATH_IMAGE038
由下式求得： Among them, the calculated value of axial deviatoric strain
Figure 812131DEST_PATH_IMAGE038
It is obtained by the following formula:
Figure 702596DEST_PATH_IMAGE039
。
Figure 702596DEST_PATH_IMAGE039
.
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