CN108152137A - A kind of method that long-term strength is determined in creep of rock experiment - Google Patents
A kind of method that long-term strength is determined in creep of rock experiment Download PDFInfo
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- CN108152137A CN108152137A CN201711453978.3A CN201711453978A CN108152137A CN 108152137 A CN108152137 A CN 108152137A CN 201711453978 A CN201711453978 A CN 201711453978A CN 108152137 A CN108152137 A CN 108152137A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- 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
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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
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0019—Compressive
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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
- G01N2203/0058—Kind of property studied
- G01N2203/0069—Fatigue, creep, strain-stress relations or elastic constants
- G01N2203/0071—Creep
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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
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/025—Geometry of the test
- G01N2203/0256—Triaxial, i.e. the forces being applied along three normal axes of the specimen
Abstract
The present invention provides a kind of method that long-term strength is determined in creep of rock experiment, is related to rock mechanics technical field.This method includes：For live rock sample core taking；It processes core and forms test specimen；It is installed for test specimen and adjusts axis radial displacement transducer；Axis radial load is applied to test specimen until test specimen destroys；Acquire test data and the output that converts；Draw test specimen axis radial direction creep curve；Calculate each moment creep Poisson's ratio；Determine Long-time strength of rock.A kind of method that long-term strength is determined in creep of rock experiment provided by the invention, it is that foundation is deformed into the practical ductility dilatation of rock, axis radial deformation influences performances of rock during considering creep of rock, creep time is segmented, draw creep Poisson's ratio time graph, Long-time strength of rock is determined according to the corresponding stress of knee of curve data, required long-term strength is made preferably to reflect rock timeliness, eliminate subjective judgement, it is simple and reliable, accuracy is higher, easy to spread to be applied to practical rock engineering.
Description
Technical field
The present invention relates to Geotechnical Engineering fields, and in particular to a kind of to determine long-term strength in creep of rock experiment
Method.
Background technology
As the depth of underground and Tunnel Engineering is continuously increased, the involved rock-soil mechanics under the conditions of complicated geological environment
Problem also more sophisticated, this brings rock engineering the problem of unprecedented and challenge.Face when the depth of deep rock mass is more than
Boundary soften depth when, deep rock mass the conditions such as gravity, tectonic stress, underground circulating water and Engineering Disturbance interaction under,
Rock mass will appear as complicated soft-rock slope characteristic.Since soft rock is by crustal stress, country rock unloading, seepage flow and tectonic stress
It influences, weak, broken, loose, expansion that soft rock shows, rheology lead to engineering problem increasingly with the undesirable properties such as severely-weathered
Increase, such as large deformation of deep coalmine tunnel surrounding, large-sized rock mass side slope are along the unstability of weak structural face and tunnel structure branch
Difficulty etc. is protected, while Practical Project also increasingly focuses on the long-term stability of geotechnical engineering and safety, this is just related to rock mass
Long-term strength problem.
It is compacted just to will appear stable state when the extraneous load level suffered by rock mass in engineering reaches at or above a certain stress limit value
Become or tertiary creep phenomenon, the stress limit value are rock generation steady creep and the critical value of unstable creep, the threshold limiting
It is exactly the long-term strength of rock.Lower rock mass engineering project ess-strain changing rule is acted on this Study on Aging Hardening, is deep rock mass engineering project
The design and maintenance of excavation and support provide corresponding scientific basis, while abundant rock mass mechanics theory and method,
The generation of engineering accident can be avoided to the maximum extent.
At present for the determining method of long-term strength research, it can mainly be summarized as two kinds：Indirect method and direct method.Indirectly
Method determines that Long-time strength of rock is judged according to the physical mechanics phenomenon showed during the rock failure mechanism of rock, by observing
Physical mechanics phenomenon, analysis find how rock is changed by intensity during external load, develop to whether the different stages goes out
Existing corresponding critical value or strong criterion.
It is mainly determined under complex stress condition using stress-strain tautochrone cluster method；In patent《Underground water seal stone
Oily cave depot country rock long-term strength determination method for parameter》(201410399007.5) it discloses and utilizes stress-strain tautochrone
Or at the uniform velocity stable state rheology stage rheological rate determines the long-term strong method of rock；Method only accounts for rock described in the patent
Axial strain changes, and does not consider that circumferential and bulk strain changes the influence to Long-time strength of rock.In view of most of rock failure mechanisms of rock
When significant volume dilatation is presented and is compressed axially, so, stress-strain tautochrone cluster method and using stress-strain etc.
When curve or at the uniform velocity stable state rheology stage rheological rate determine that method only considers axial strain, there are one is determined to long-term strength
Determine error.At the uniform velocity stable state rheology stage rheological rate method is that the secondary creep rates of rock sample are described by exponential function, into
And think that the inflection point of exponential function is the long-term strength of rock；In view of exponential function is smooth curve, inflection point is simultaneously indefinite,
Intuitively its inflection point, which is observed, will certainly cause certain error；And since three direction rheological rate curvilinear motion rules exist
Certain difference leads to inflection point and differs, and is determined for a long time using the rheological rate knee of curve in which direction in Practical Project
Intensity is worth the problem of disputing on.
In conclusion be respectively provided with must subjectivity for the method for existing judgement long-term strength.Therefore it is urgent to provide a kind of new
, Long-time strength of rock quantitative, applied widely, that accuracy is high determine method.
Invention content
In view of the problems of the existing technology, the present invention provides a kind of side that long-term strength is determined in creep of rock experiment
Method is to be deformed into foundation with the practical ductility dilatation of rock, considers creep of rock process Axial Deformation and radial deformation pair
Performances of rock influences, and calculates the ratio Poisson's ratio between axial deformation ability and radial deformation, by Poisson's ratio regard as at any time with
The variable quantity of stress starts divergence point year corresponding stress according to creep Poisson's ratio-time graph inflection point data and determines rock
Long-term strength can more reflect the essence of rock, ensure that required long-term strength can preferably reflect rock timeliness.
To achieve these goals, a kind of method that long-term strength is determined in creep of rock experiment, includes the following steps：
Step 1：Rock sample after live simple cutting is modified with cutting machine so that it can be placed on corning machine；
Step 2：With corning machine using water drilling method to rock sample core taking, machining accuracy in strict accordance with《Rock test method standard》
(GB50218-94) it carries out, the shape for making its core is cylinder, and a diameter of 50mm is highly 100mm, is cut and justified using cutting machine
Two end faces of column are simultaneously polished, and it is for use that final test specimen is made；Wherein, on the axial length direction of test specimen, diameter error
Without departing from diameter threshold, the nonparallelism maximum in test specimen two ends face is no more than depth of parallelism threshold value, makes test specimen two ends face perpendicular to examination
Part axis, and maximum deviation is no more than deviation threshold；
Step 3：Test specimen is fixed on and is put into after testing stand in the final triaxial cell tested, is test specimen installation axle
Radial displacement transducer, and axis radial direction strain value is adjusted to testing regulations claimed range, it is as follows：
Step 3.1 measures the size and quality of test specimen, by measurement result input test system；
Step 3.2：Vaseline is uniformly smeared in test specimen two ends face, is the heat-shrinkable T bush of oil resistant on specimen sleeve, test specimen is put
In on operating platform, placing force snesor respectively in the top and bottom of test specimen and being aligned, casing is blown with blowing hot wind baking, makes casing
It is close to test specimen, while utilizes thin wire cuff pipe and iron block junction；
Step 3.3：The chain type lateral displacement that LVDT shaft position sensors and range that range is 5mm are 5mm is sensed
Device is installed on test specimen, makes lateral displacement sensor horizontal with the holding of test specimen bottom surface, the contact point of shaft position sensor is symmetrical
It is and horizontal；
Step 3.4：It connects sensor and measures the plug of strain equipment, adjust sensor, will axially and radially strain
Value is adjusted to testing regulations claimed range, and the test specimen debugged is placed in servo testing machine bearing plate center；
Step 4：Displacement upper limit value is set, axis radial load is applied to test specimen using displacement-control mode, until test specimen is broken
It is bad, it is as follows：
Step 4.1：The compression strength in mean compressive strength section in triaxial compression test table is taken, selectes confining pressure, is used
Displacement-control mode applies first order axis radial load to sample, carries out the experiment of three axis conventional compacts；
Step 4.2：If within certain load duration, the axial deflection for measuring test specimen is not more than deformation threshold value,
Then think to deform basicly stable, record axis radial strain under this load action and axis radial strain and change with axis pressuring stress level
Data；The load duration is determined according to time actual strain deformation；
Step 4.3：Judge whether test specimen occurs unstable failure, if so, step 5 is performed, if it is not, then increasing axis compression
Level, and be adjusted according to loading environment, return to step 4.2, next stage axis radial load is applied to sample；
Step 5：By testing machine automatic collection test data, corresponding strain and stress are converted into, is output to data acquisition
System；
Step 6：Test specimen axis Radial creep the Complete Curve is drawn, is as follows：
Step 6.1：Using the method that experimental data exceptional value in linear fit is rejected based on Schottky photodetectors, pass through
Origin softwares carry out abnormality value removing to three axis creep test data on the basis of validity is ensured；
Step 6.2：Nonlinear data fitting is carried out to the creep curve under upper level load action, is asked according to fit equation
Go out upper level load finish time to when the deflection at each moment between prime load finish time is relative to upper level load knot
The value added of the deflection at beam moment；
Step 6.3：Deflection when prime load finish time is subtracted with when testing deflection under prime load action
Value added, so as to after being corrected when prime creep test curve；
Step 6.4：Step 6.2 is carried out one by one to subsequent stages load creep curve to step 6.3, finally obtains amendment
Load creep test curves at different levels afterwards；
Step 7：According to the axis radial direction deformation of creep amount that measures of experiment, during creep by calculating each moment, test specimen is being pressed
The ratio of transverse strain value and axial strain value when contracting or stretching, i.e. creep Poisson's ratio, obtain test specimen creep Poisson's ratio at any time
Between changing value；
Step 8：Creep time is segmented, creep Poisson's ratio is inscribed when choosing each, draws creep under the conditions of hierarchical loading
Poisson's ratio changes over time relational graph, determines that creep Poisson's ratio changes over time the corresponding stress that knee of curve starts divergence point
Value, as Long-time strength of rock.
Diameter threshold is 0.3mm in the step 2, and depth of parallelism threshold value is 0.05mm, and deviation threshold is 0.25 °.
Compression strength section is 40%~80% in the step 4.1.
It is 0.001mm that threshold value is deformed in the step 4.2.
Fit equation in the step 6.2 is shown below：
Wherein, E1、E2For elasticity modulus, η1For viscid property coefficient, σ is stress, and ε is strain, and t is the time.
Beneficial effects of the present invention：
The present invention proposes a kind of method that long-term strength is determined in creep of rock experiment, is with the practical ductility dilatation of rock
Foundation is deformed into, considering creep of rock process Axial Deformation influences performances of rock with radial deformation, calculates axial become
The Poisson's ratio μ of rock is assumed to a non-definite value by the ratio Poisson's ratio between shape ability and radial deformation, and rock is as a kind of
Complicated viscoelasto-plastic material, under outer load action, with the continuous reduction and recombination of rock interior structure, rock it is basic
Physico-mechanical properties are also being constantly occurring variation, therefore analyze Poisson's ratio and stress state and the relationship of time, by Poisson
It can more reflect the essential attribute of rock with the variable quantity of stress at any time than regarding as.Creep time is divided into several sections, chooses phase
Creep Poisson's ratio under state is answered, creep Poisson's ratio is drawn and changes over time relational graph；Start to send out according to above-mentioned knee of curve data
Scatterplot determines Long-time strength of rock with corresponding stress, ensure that required long-term strength can preferably reflect rock timeliness
Property, based on the loading Creep Mechanics experiment of rock multistage stress grading, subjective judgement is eliminated, simple and reliable, accuracy is higher, easily
In being applied to practical rock engineering.
Description of the drawings
Fig. 1 is the method flow diagram that long-term strength is determined in creep of rock experiment of the embodiment of the present invention；
Fig. 2 is the flow chart of step 3 in the method that long-term strength is determined during creep of rock is tested of the embodiment of the present invention；
Fig. 3 is the flow chart of step 4 in the method that long-term strength is determined during creep of rock is tested of the embodiment of the present invention；
Fig. 4 is the flow chart of step 6 in the method that long-term strength is determined during creep of rock is tested of the embodiment of the present invention；
Fig. 5 is that the confining pressure classification of determining of the embodiment of the present invention adds axis to press creep test creep curve；
Fig. 6 is that the confining pressure classification of determining of the embodiment of the present invention adds axis to press creep test creep Poisson's ratio curve；
Fig. 7 is creep Poisson's ratio and the stress whens waiting determining confining pressure classification and add axis that creep test is pressed to obtain of the embodiment of the present invention
Relationship.
Specific embodiment
It is right in the following with reference to the drawings and specific embodiments in order to be more clear the purpose of the present invention, technical solution and advantage
The present invention is described in further details.Specific embodiment described herein only to explain the present invention, is not used to limit this
Invention.
A kind of method that long-term strength is determined in creep of rock experiment, flow is as shown in Figure 1, the following institute of specific method
It states：
Step 1：Rock sample after live simple cutting is modified with cutting machine so that it can be placed on corning machine.
Step 2：With corning machine using water drilling method to rock sample core taking, machining accuracy in strict accordance with《Rock test method standard》
(GB50218-94) it carries out, the shape for making its core is cylinder, and a diameter of 50mm is highly 100mm, is cut and justified using cutting machine
Two end faces of column are simultaneously polished, and it is for use that final test specimen is made；Wherein, on the axial length direction of test specimen, diameter error
Without departing from diameter threshold 0.3mm, the nonparallelism maximum in test specimen two ends face is no more than depth of parallelism threshold value 0.05mm, makes test specimen two ends
Face is perpendicular to test specimen axis, and maximum deviation is no more than 0.25 ° of deviation threshold.
Step 3：Test specimen is fixed on and is put into after testing stand in the final triaxial cell tested, is test specimen installation axle
Radial displacement transducer, and axis radial direction strain value is adjusted to testing regulations claimed range, flow is as shown in Fig. 2, specific step
It is rapid as follows：
Step 3.1 measures the size and quality of test specimen, by measurement result input test system.
Step 3.2：Vaseline is uniformly smeared in test specimen two ends face, is the heat-shrinkable T bush of oil resistant on specimen sleeve, test specimen is put
In on operating platform, placing force snesor respectively in the top and bottom of test specimen and being aligned, casing is blown with blowing hot wind baking, makes casing
It is close to test specimen, while utilizes thin wire cuff pipe and iron block junction.
In the present embodiment, it is to reduce the frictional force between stiffness bearer and test specimen end face, maximum limit to smear vaseline
End effect is eliminated on degree ground, casing is enabled to be close to test specimen, while be in order to ensure close using thin wire cuff pipe and iron block junction
Feng Xing avoids rock debris after sample oil inlet and test specimen destroy during the experiment from polluting oil.
Step 3.3：The chain type lateral displacement that LVDT shaft position sensors and range that range is 5mm are 5mm is sensed
Device is installed on test specimen, makes lateral displacement sensor horizontal with the holding of test specimen bottom surface, the contact point of shaft position sensor is symmetrical
It is and horizontal.
Step 3.4：It connects sensor and measures the plug of strain equipment, adjust sensor, will axially and radially strain
Value is adjusted to testing regulations claimed range, and the test specimen debugged is placed in servo testing machine bearing plate center.
Step 4：Displacement upper limit value is set, axis radial load is applied to test specimen using displacement-control mode, until test specimen is broken
Bad, flow is as shown in figure 3, be as follows：
Step 4.1：Compression strength different in mean compressive strength section 40%~80% in triaxial compression test table is taken,
Selected confining pressure σ3For 10MPa, first order axis radial load 40MPa is applied to sample using displacement-control mode, it is normal to carry out three axis
Advise compression test.
Step 4.2：If in certain load duration t, the axial deflection of test specimen is measured no more than deformation threshold value
0.001mm, then it is assumed that deformation is basicly stable, records the axis radial direction strain stress under this load action1With axis radial direction strain stress1With axis pressure
Stress level σ1Delta data.Load duration t is determined according to time actual strain deformation.
Step 4.3：Judge whether test specimen occurs unstable failure, if so, step 5 is performed, if it is not, then increasing axis compression
Horizontal σ1, and be adjusted according to loading environment, return to step 4.2, next stage axis radial load is applied to sample.
In the present embodiment, apply the axis radial load of 50Mpa, 60Mpa, 70Mpa to test specimen respectively, wherein, when to test specimen
When applying the axis radial load of 70Mpa, unstable failure occurs for test specimen.
Step 5：By testing machine automatic collection test data, corresponding strain and stress are converted into, is output to data acquisition
System.
The testing machine device systems are made of loading section, part of detecting and control section three parts, have axis pressure, confining pressure
With three sets of independent Close loop servo control functions of pore water pressure, objective reliable, the precision height of test data of acquisition.The present embodiment selects
It selects single sample graded loading way and carries out creep test, and load early period can be reduced using corresponding method to a certain extent
Historical influence.
Creep test refer to set displacement upper limit value, classification increase axis pressure creep test when use load control mode with
The loading speed of 500N/s applies xial feed up to pre- constant load, and sets the load duration as 25h, similarly sets latter
Grade load and duration.Three axis creep test step and three axis routine test steps are roughly the same, and only load mode is slightly
It is different.
Step 6：Test specimen axis Radial creep the Complete Curve is drawn, flow is as shown in figure 4, be as follows：
Step 6.1：Using the method that experimental data exceptional value in linear fit is rejected based on Schottky photodetectors, pass through
Origin softwares carry out abnormality value removing to three axis creep test data on the basis of validity is ensured.
Step 6.2：Nonlinear data fitting is carried out to the creep curve under upper level load action, is asked according to fit equation
Go out upper level load finish time t1To as prime load σ0+ Δ σ finish time t2Between each moment deflection relative to upper one
Grade load finish time t1Deflection ε1Value added Δ ε(t)。
Shown in fit equation such as formula (1)：
Wherein, E1、E2For elasticity modulus, η1For viscid property coefficient, σ is stress, and ε is strain, and t is the time.
Step 6.3：Deflection when prime load finish time is subtracted with when testing deflection under prime load action
Value added, so as to after being corrected when prime creep test curve.
Step 6.4：Step 6.2 is carried out one by one to subsequent stages load creep curve to step 6.3, finally obtains amendment
Load creep test curves at different levels afterwards.
As shown in figure 5, axial deformation characteristic shows as compression failure, sample experienced 4 grades of lotuses altogether under the conditions of confining pressure 10MPa
It carries, respectively 40MPa, 50MPa, 60MPa and 70MPa, under the effect of 40MPa axial stresses, the instantaneous strain of test specimen is
0.0768%, it accounts under 94.2%, the 50MPa axial stresses effect of overall strain, the instantaneous strain of test specimen accounts for the 95.4% of overall strain,
Under the effect of 70MPa axial stresses, there is the tertiary creep stage in test specimen, and instantaneous strain value is 0.2232%, accounts for overall strain
80.4%, the increase of instantaneous strain is not only related with load stress level, but also is influenced by load history is loaded early period.
Step 7：According to the axis radial direction deformation of creep amount that experiment measures, by calculating the creep Poisson's ratio at each moment, test specimen
The ratio of transverse strain value and axial strain value in compression or stretching, i.e. creep Poisson's ratio, obtain test specimen creep Poisson's ratio
Change over time value.
Shown in the calculation formula of creep Poisson's ratio such as formula (2)：
Wherein, μ be creep Poisson's ratio, εxFor transverse strain value, εyFor axial strain value.
Step 8：Creep time is segmented, creep Poisson's ratio is inscribed when choosing each, draws creep under the conditions of hierarchical loading
Poisson's ratio changes over time relational graph, determines that creep Poisson's ratio changes over time the corresponding stress that knee of curve starts divergence point
Value, as Long-time strength of rock.
In the present embodiment, confining pressure for 10MPa, grading shaft press 40MPa, 50MPa, 60MPa, 70MPa effect, take t=
0.5h, 2h, 8h, 16h, for 24 hours, 32h, 40h, 48h and its more special time point under every group of Structure Under Axial Compression, choose Fig. 2
In axial and radial strain data under each time, creep Poisson ratio is calculated according to formula (2) and is shown in Table 1, and draw
Go out creep Poisson's ratio and the relationship of time, as shown in Figure 6.
1 σ of table3=10MPa creep Poisson's ratios
As shown in fig. 7, comparison axis radially etc. whens stress curve, it can be found that diametral curve than axial curve earlier into non-
The linear change stage, and the incrementss of radial strain at any time are more than axial strain under stress level at different levels, this shows radially compacted
The stress threshold values of change is lower than axial stress threshold values, and Radial creep characteristic is more sensitive compared with Axial creep, and creep Poisson's ratio is comprehensive
Sympodium diameter strain creep amount, under outer load action, with the continuous reduction and recombination of rock interior structure, the basic object of rock
Reason mechanical property is also being constantly occurring variation, therefore analyze Poisson's ratio and stress state and the relationship of time, by Poisson's ratio
The essential attribute of rock can more be reflected with the variable quantity of stress at any time by regarding as, and stress-creep Poisson's ratio curve is deposited whens similary etc.
In an apparent turning point, whens this turning point is with waiting as ess-strain, curve is divided into linearity range and non-linear section two
Point, rock mainly shows viscoplasticity before turning point, is mainly shown as visco-plasticity after turning point, rock interior structure is bright
It is aobvious to deteriorate, and gradually start to destroy, you can regarded as weakening creeping and steady creep boundary point.
Claims (7)
- A kind of 1. method that long-term strength is determined in creep of rock experiment, which is characterized in that include the following steps：Step 1：Rock sample after live simple cutting is modified with cutting machine so that it can be placed on corning machine；Step 2：With corning machine using water drilling method to rock sample core taking, machining accuracy in strict accordance with《Rock test method standard》 (GB50218-94) it carries out, the shape for making its core is cylinder, and a diameter of 50mm is highly 100mm, is cut and justified using cutting machine Two end faces of column are simultaneously polished, and it is for use that final test specimen is made；Wherein, on the axial length direction of test specimen, diameter error Without departing from diameter threshold, the nonparallelism maximum in test specimen two ends face is no more than depth of parallelism threshold value, makes test specimen two ends face perpendicular to examination Part axis, and maximum deviation is no more than deviation threshold；Step 3：Test specimen is fixed on and is put into after testing stand in the final triaxial cell tested, is test specimen installation axle radial direction Displacement sensor, and axis radial direction strain value is adjusted to testing regulations claimed range；Step 4：Displacement upper limit value is set, axis radial load is applied to test specimen using displacement-control mode, until test specimen destroys；Step 5：By testing machine automatic collection test data, corresponding strain and stress are converted into, is output to data collecting system；Step 6：Test specimen axis Radial creep the Complete Curve is drawn, is as follows：Step 6.1：It is soft by Origin using the method that experimental data exceptional value in linear fit is rejected based on Schottky photodetectors Part carries out abnormality value removing to three axis creep test data on the basis of validity is ensured；Step 6.2：Nonlinear data fitting is carried out to the creep curve under upper level load action, is obtained according to fit equation Level-one load finish time is extremely at the end of the deflection at each moment between prime load finish time is relative to upper level load The value added of the deflection at quarter；Step 6.3：With when under prime load action test deflection subtract when the increase of the deflection of prime load finish time Value, so as to work as prime creep test curve after being corrected；Step 6.4：Step 6.2 is carried out one by one to subsequent stages load creep curve to step 6.3, is finally obtained after correcting Load creep test curves at different levels；Step 7：According to the axis radial direction deformation of creep amount that measures of experiment, during creep by calculating each moment, test specimen in compression or The ratio of transverse strain value and axial strain value when person stretches, i.e. creep Poisson's ratio, obtain test specimen creep Poisson's ratio and become at any time Change value；Step 8：Creep time is segmented, creep Poisson's ratio is inscribed when choosing each, draws creep Poisson under the conditions of hierarchical loading Than changing over time relational graph, determine that creep Poisson's ratio changes over time the corresponding stress value that knee of curve starts divergence point, As Long-time strength of rock.
- 2. the method according to claim 1 that long-term strength is determined in creep of rock experiment, which is characterized in that the step Diameter threshold is 0.3mm in rapid 2, and depth of parallelism threshold value is 0.05mm, and deviation threshold is 0.25 °.
- 3. the method according to claim 1 that long-term strength is determined in creep of rock experiment, which is characterized in that the step Rapid 3 include the following steps：Step 3.1 measures the size and quality of test specimen, by measurement result input test system；Step 3.2：Vaseline is uniformly smeared in test specimen two ends face, is the heat-shrinkable T bush of oil resistant on specimen sleeve, test specimen is placed in behaviour Make on platform, place force snesor respectively in the top and bottom of test specimen and be aligned, blow casing with blowing hot wind baking, be close to casing Test specimen, while utilize thin wire cuff pipe and iron block junction；Step 3.3：The chain type lateral displacement sensor that LVDT shaft position sensors and range that range is 5mm are 5mm is pacified It is attached on test specimen, makes lateral displacement sensor horizontal with test specimen bottom surface holding, the contact point of shaft position sensor is symmetrical and water It is flat；Step 3.4：It connects sensor and measures the plug of strain equipment, adjust sensor, it will axially and radially strain value tune It is whole in testing regulations claimed range, the test specimen debugged is placed in servo testing machine bearing plate center.
- 4. the method according to claim 1 that long-term strength is determined in creep of rock experiment, which is characterized in that the step Rapid 4 include the following steps：Step 4.1：The compression strength in mean compressive strength section in triaxial compression test table is taken, confining pressure is selected, using displacement Control mode applies first order axis radial load to sample, carries out the experiment of three axis conventional compacts；Step 4.2：If within certain load duration, the axial deflection of test specimen is measured no more than deformation threshold value, then is recognized Basicly stable to deform, the axis radial strain and axis radial strain recorded under this load action changes number with axis pressuring stress level According to；The load duration is determined according to time actual strain deformation；Step 4.3：Judge whether test specimen occurs unstable failure, if so, step 5 is performed, if it is not, then increasing axis compression water It is flat, and be adjusted according to loading environment, return to step 4.2, next stage axis radial load is applied to sample.
- 5. the method according to claim 4 that long-term strength is determined in creep of rock experiment, which is characterized in that the step Mean compressive strength section is 40%~80% in rapid 4.1.
- 6. the method according to claim 4 that long-term strength is determined in creep of rock experiment, which is characterized in that the step It is 0.001mm that threshold value is deformed in rapid 4.2.
- 7. the method according to claim 1 that long-term strength is determined in creep of rock experiment, which is characterized in that the step Fit equation in rapid 6.2 is shown below：Wherein, E1、E2For elasticity modulus, η1For viscid property coefficient, σ is stress, and ε is strain, and t is the time.
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Cited By (23)
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| CN109297841A (en) * | 2018-11-29 | 2019-02-01 | 四川大学 | Test the test method of mechanical behaviors of rocks under tension and compression alternate stress |
| CN109387433A (en) * | 2018-10-15 | 2019-02-26 | 西安建筑科技大学 | The method for determining Rock Under Uniaxial Compression long-term strength based on secondary creep rates inverse |
| CN109870371A (en) * | 2019-03-28 | 2019-06-11 | 中南大学 | A kind of creep compression test device |
| CN110044716A (en) * | 2019-02-02 | 2019-07-23 | 中南大学 | Rock burst proneness Grade Judgment of the response lag than index is unloaded based on adding |
| CN110082207A (en) * | 2019-05-05 | 2019-08-02 | 中国人民解放军陆军装甲兵学院 | Detect method and apparatus, system and the storage medium of coating material strain failure |
| CN110542615A (en) * | 2019-09-06 | 2019-12-06 | 山东大学 | High-temperature triaxial unloading rheological test method for hard and brittle rock |
| CN110610062A (en) * | 2019-10-21 | 2019-12-24 | 安徽理工大学 | Rock elastic modulus calculation method under long-term static load effect |
| CN110631908A (en) * | 2019-09-17 | 2019-12-31 | 西安建筑科技大学 | Construction method of creep damage model of rock uniaxial compression overall process |
| CN110704917A (en) * | 2019-09-24 | 2020-01-17 | 中铁三局集团有限公司 | Method, device, equipment and storage medium for determining tunnel excavation inverted arch step distance |
| CN111323310A (en) * | 2020-04-15 | 2020-06-23 | 高军 | Experimental device and method for soft rock loading and unloading plastic creep simulation |
| CN111366457A (en) * | 2020-02-23 | 2020-07-03 | 浙江大学 | Device and method for measuring long-term creep of steel cable |
| CN111366452A (en) * | 2020-03-26 | 2020-07-03 | 北京科技大学 | Method for measuring energy storage level of self-energy-storage rock mass |
| CN111595677A (en) * | 2020-06-03 | 2020-08-28 | 中国电建集团成都勘测设计研究院有限公司 | Soft rock long-term strength value determining method and soft rock bearing capacity determining method |
| CN111666687A (en) * | 2020-06-08 | 2020-09-15 | 中国电建集团成都勘测设计研究院有限公司 | Method for simulating influence of surrounding rock unloading on stress of large-span cavern supporting structure |
| CN111678787A (en) * | 2020-06-16 | 2020-09-18 | 中国矿业大学 | Rock long-term strength determination method based on numerical fitting |
| CN111896372A (en) * | 2020-06-29 | 2020-11-06 | 河海大学 | Analysis method suitable for analyzing horizontal deformation characteristics of rock test piece |
| CN112284902A (en) * | 2020-10-28 | 2021-01-29 | 哈尔滨工业大学 | Conversion method from triaxial creep test result of graded loading rock soil to respective loading |
| CN112649278A (en) * | 2020-11-27 | 2021-04-13 | 宁夏大学 | Method for testing metal creep property |
| CN112946086A (en) * | 2021-02-02 | 2021-06-11 | 江西理工大学 | Rock creep rupture microcrack nucleation starting time identification method |
| CN113281148A (en) * | 2021-05-19 | 2021-08-20 | 江西理工大学 | Method for identifying initial time of rock creep damage microcrack penetration stage |
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| CN115372148A (en) * | 2022-10-24 | 2022-11-22 | 中国中医科学院望京医院(中国中医科学院骨伤科研究所) | Axial loading device, method and loading system for spine |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0602980A3 (en) * | 1992-12-16 | 1995-04-05 | Halliburton Co | Method of perforating a well. |
| CN103344489A (en) * | 2013-06-17 | 2013-10-09 | 镇江铁科橡塑制品有限公司 | Material creep property testing device |
| CN105043905A (en) * | 2015-06-29 | 2015-11-11 | 河海大学 | Method for determining long-term strength parameter of rock based on steady-flow variable-rate tangent line |
| WO2016162642A1 (en) * | 2015-04-09 | 2016-10-13 | Aurock | Method of controlling a superplastic forming machine and corresponding machine |
| CN106198259A (en) * | 2016-07-05 | 2016-12-07 | 辽宁工程技术大学 | A kind of method determining rock monsteady state creep parameter |
-
2017
- 2017-12-28 CN CN201711453978.3A patent/CN108152137B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0602980A3 (en) * | 1992-12-16 | 1995-04-05 | Halliburton Co | Method of perforating a well. |
| CN103344489A (en) * | 2013-06-17 | 2013-10-09 | 镇江铁科橡塑制品有限公司 | Material creep property testing device |
| WO2016162642A1 (en) * | 2015-04-09 | 2016-10-13 | Aurock | Method of controlling a superplastic forming machine and corresponding machine |
| CN105043905A (en) * | 2015-06-29 | 2015-11-11 | 河海大学 | Method for determining long-term strength parameter of rock based on steady-flow variable-rate tangent line |
| CN106198259A (en) * | 2016-07-05 | 2016-12-07 | 辽宁工程技术大学 | A kind of method determining rock monsteady state creep parameter |
Non-Patent Citations (2)
| Title |
|---|
| JULIA SHEKHOVTSOVA等: "Evaluation of short-and long-term properties of heat-cured alkali-activated fly ash concrete", 《MAGZINE OF CONCRETE RESEARCH》 * |
| 刘传孝等: "分级加卸载硬岩短时蠕变特性实验研究", 《实验力学》 * |
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| CN109387433A (en) * | 2018-10-15 | 2019-02-26 | 西安建筑科技大学 | The method for determining Rock Under Uniaxial Compression long-term strength based on secondary creep rates inverse |
| CN109387433B (en) * | 2018-10-15 | 2020-09-29 | 西安建筑科技大学 | Method for determining uniaxial long-term strength of rock based on inverse steady-state creep rate |
| CN109297841A (en) * | 2018-11-29 | 2019-02-01 | 四川大学 | Test the test method of mechanical behaviors of rocks under tension and compression alternate stress |
| CN110044716A (en) * | 2019-02-02 | 2019-07-23 | 中南大学 | Rock burst proneness Grade Judgment of the response lag than index is unloaded based on adding |
| CN109870371A (en) * | 2019-03-28 | 2019-06-11 | 中南大学 | A kind of creep compression test device |
| CN109870371B (en) * | 2019-03-28 | 2023-08-29 | 中南大学 | Creep compression experimental device |
| CN110082207A (en) * | 2019-05-05 | 2019-08-02 | 中国人民解放军陆军装甲兵学院 | Detect method and apparatus, system and the storage medium of coating material strain failure |
| CN110542615A (en) * | 2019-09-06 | 2019-12-06 | 山东大学 | High-temperature triaxial unloading rheological test method for hard and brittle rock |
| CN110631908A (en) * | 2019-09-17 | 2019-12-31 | 西安建筑科技大学 | Construction method of creep damage model of rock uniaxial compression overall process |
| CN110631908B (en) * | 2019-09-17 | 2021-10-22 | 西安建筑科技大学 | Construction method of creep damage model of rock uniaxial compression overall process |
| CN110704917A (en) * | 2019-09-24 | 2020-01-17 | 中铁三局集团有限公司 | Method, device, equipment and storage medium for determining tunnel excavation inverted arch step distance |
| CN110704917B (en) * | 2019-09-24 | 2023-02-03 | 中国国家铁路集团有限公司 | Method, device, equipment and storage medium for determining tunnel excavation inverted arch step distance |
| CN110610062A (en) * | 2019-10-21 | 2019-12-24 | 安徽理工大学 | Rock elastic modulus calculation method under long-term static load effect |
| CN110610062B (en) * | 2019-10-21 | 2021-09-17 | 安徽理工大学 | Rock elastic modulus calculation method under long-term static load effect |
| CN111366457A (en) * | 2020-02-23 | 2020-07-03 | 浙江大学 | Device and method for measuring long-term creep of steel cable |
| CN111366457B (en) * | 2020-02-23 | 2021-08-06 | 浙江大学 | Device and method for measuring long-term creep of steel cable |
| CN111366452A (en) * | 2020-03-26 | 2020-07-03 | 北京科技大学 | Method for measuring energy storage level of self-energy-storage rock mass |
| CN111366452B (en) * | 2020-03-26 | 2021-01-29 | 北京科技大学 | Method for measuring energy storage level of self-energy-storage rock mass |
| CN111323310A (en) * | 2020-04-15 | 2020-06-23 | 高军 | Experimental device and method for soft rock loading and unloading plastic creep simulation |
| CN111323310B (en) * | 2020-04-15 | 2022-05-20 | 高军 | Experimental device and method for soft rock loading and unloading plastic creep simulation |
| CN111595677B (en) * | 2020-06-03 | 2023-01-24 | 中国电建集团成都勘测设计研究院有限公司 | Soft rock long-term strength value determining method and soft rock bearing capacity determining method |
| CN111595677A (en) * | 2020-06-03 | 2020-08-28 | 中国电建集团成都勘测设计研究院有限公司 | Soft rock long-term strength value determining method and soft rock bearing capacity determining method |
| CN111666687A (en) * | 2020-06-08 | 2020-09-15 | 中国电建集团成都勘测设计研究院有限公司 | Method for simulating influence of surrounding rock unloading on stress of large-span cavern supporting structure |
| CN111678787A (en) * | 2020-06-16 | 2020-09-18 | 中国矿业大学 | Rock long-term strength determination method based on numerical fitting |
| CN111678787B (en) * | 2020-06-16 | 2022-05-17 | 中国矿业大学 | Rock long-term strength determination method based on numerical fitting |
| CN111896372A (en) * | 2020-06-29 | 2020-11-06 | 河海大学 | Analysis method suitable for analyzing horizontal deformation characteristics of rock test piece |
| CN112284902A (en) * | 2020-10-28 | 2021-01-29 | 哈尔滨工业大学 | Conversion method from triaxial creep test result of graded loading rock soil to respective loading |
| CN112649278A (en) * | 2020-11-27 | 2021-04-13 | 宁夏大学 | Method for testing metal creep property |
| CN112946086B (en) * | 2021-02-02 | 2022-09-30 | 江西理工大学 | Rock creep rupture microcrack nucleation starting time identification method |
| CN112946086A (en) * | 2021-02-02 | 2021-06-11 | 江西理工大学 | Rock creep rupture microcrack nucleation starting time identification method |
| CN113281148A (en) * | 2021-05-19 | 2021-08-20 | 江西理工大学 | Method for identifying initial time of rock creep damage microcrack penetration stage |
| CN113281148B (en) * | 2021-05-19 | 2022-09-09 | 江西理工大学 | Method for identifying initial time of rock creep damage microcrack penetration stage |
| CN113295526A (en) * | 2021-05-24 | 2021-08-24 | 辽宁工程技术大学 | Method for correcting displacement of testing machine by using resistance strain data |
| CN113295526B (en) * | 2021-05-24 | 2022-04-26 | 辽宁工程技术大学 | Method for correcting displacement of testing machine by using resistance strain data |
| WO2023197824A1 (en) * | 2022-04-15 | 2023-10-19 | 安徽理工大学 | Rock creep model viscoelasticity parameter acquisition method based on deformation modulus |
| CN115372148B (en) * | 2022-10-24 | 2023-01-31 | 中国中医科学院望京医院(中国中医科学院骨伤科研究所) | Axial loading device, method and loading system for spine |
| CN115372148A (en) * | 2022-10-24 | 2022-11-22 | 中国中医科学院望京医院(中国中医科学院骨伤科研究所) | Axial loading device, method and loading system for spine |
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