CN107977544A - The elastic strain that test specimen is constrained in temperature-stress test calculates method and its system - Google Patents
The elastic strain that test specimen is constrained in temperature-stress test calculates method and its system Download PDFInfo
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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
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- 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
- G01N2203/0075—Strain-stress relations or elastic constants
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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
- G01N2203/022—Environment of the test
- G01N2203/0222—Temperature
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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
- G01N2203/06—Indicating or recording means; Sensing means
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Abstract
The elastic strain that test specimen is constrained in being tested the present invention provides a kind of temperature stress calculates method, comprises the following steps：A：The Flexible Reset that the reset test specimen generation of Flexible Reset stage collet is obtained by testing machine strains；B：Equivalent Elasticity caused by obtaining the development of reseting interval Equivalent Elasticity stage, internal stress period by Equivalent Elasticity strain calculation method strains；C：The elastic strain of a reply cycle inner concrete is obtained by replying elastic strain calculating method in the cycle with reference to the Flexible Reset strain obtained in step A and the Equivalent Elasticity strain obtained in step B, then the elastic strain in each reply cycle adds up and tries to achieve the elastic strain of constraint test specimen.Present invention additionally comprises elastic strain calculation system in the temperature stress experiment using the method for the present invention.The present invention has the advantages that framework is simple, and result of the test is accurate, and application is extensive.
Description
Technical field
The invention belongs to the elasticity of test specimen is constrained in temperature-stress test field, more particularly to a kind of temperature-stress test
Strain calculation method and its system.
Background technology
Concrete cracking sensitivity is analyzed and CRACKING RISK is always that concrete science research and engineering circles are paid close attention to
Hot issue.The mass concrete of the engineerings such as large-scale water conservancy and hydropower, port and pier, high-speed railway, bridge, nuclear power, wind-powered electricity generation, show
There is vital influence to the durability, safety of structure and economy of engineering for the problem of Cracking of high performance concrete.
Crack for caused by mass concrete temperature stress, in past 40 years, using temperature-stress test
Method carries out achieving substantial amounts of achievement in terms of cracking of reinforced concrete evaluation study.
The development of external temperature stress testing machine is more early, domestic until 2002, Tsinghua University Qin Wei ancestrals and Lin Zhi sea bases in
The principle of second generation single shaft restraint device just develops First temperature stress testing machine (TSTM-C I), and the testing machine is each
The index of prototype is substantially met in item performance, is performed well in terms of measurement restrained deformation and restraint stress.Zhang Tao is in TSTM-C I
On the basis of develop temperature stress testing machine closed loop measurement and control system (TSTM-C II), and established by temperature stress experiment more
Group calorifics and mechanical model.Wuhan University of Technology has developed humidity controllable system on this basis, can supplement wind-heat it is air-cooled when
The moisture loss caused by concrete.
In the temperature-stress test carried out based on domestic temperature-pressure tester, main test specimen that discovery system provides
The elastic strain of (constraint test specimen) is substantially less than normal, according to this elastic strain try to achieve creep-shrinkage ratio is even as high as 0.98, hence it is evident that
Deviate normal range value.
The content of the invention
The present invention will overcome the disadvantages mentioned above of the prior art, there is provided be constrained in a kind of high temperature-stress test of accuracy
Test specimen elastic strain calculates method and its system.
The present invention tries to achieve the constraint correct elastic strain of test specimen in temperature-stress test, to determine creeping for concrete.
The present invention measures the data such as age of concrete, free strain, motor operating number, real-time displacement in temperature-stress test
On the basis of, there is provided a kind of computational methods and its system for improving elastic strain in the temperature-stress test for calculating accuracy.
To reach above-mentioned purpose, present invention employs following technical proposal：
Elastic strain calculation method, comprises the following steps in the temperature-stress test of the present invention：
A：Flexible Reset stage collet is obtained by testing machine and resets the Flexible Reset produced strain；
B：The development of reseting interval Equivalent Elasticity stage, internal stress period is obtained by Equivalent Elasticity strain calculation method to lead
The Equivalent Elasticity strain of cause；
C：With reference to the Flexible Reset strain obtained in step A and the Equivalent Elasticity strain obtained in step B by replying week
Elastic strain calculates method and obtains the elastic strain of a reply cycle inner concrete in phase, then by the bullet in each reply cycle
Property the cumulative elastic strain for trying to achieve constraint test specimen of strain.
In the elastic strain calculating method of above-mentioned temperature-stress test, the step A and step B can be synchronous
Carry out, or exchange sequencing；
In the elastic strain calculating method of above-mentioned temperature-stress test, in step, testing machine obtains resetting bullet
Property strain method it is as follows：
By Flexible Reset strain calculation method according to stepper motor in t1’-t1The Flexible Reset stage in carry out reset production
Flexible Reset strain is tried to achieve in raw displacement.
In the elastic strain calculating method of above-mentioned temperature-stress test, the Flexible Reset strain calculation method is
Formula 1., i.e.,
M1=n/L is 1.
Wherein, n：Test specimen is in t1’-t1Reset limit value in the Flexible Reset stage；
L：The effective length of test specimen；
m1：In t1’-t1The Flexible Reset stage in collet reset the strain, that is, Flexible Reset strain produced.
In the elastic strain calculating method of above-mentioned temperature-stress test, in stepb, the Equivalent Elasticity should
Become computational methods to comprise the following steps：Its elasticity modulus is first determined according to the equivalent age of concrete, then according to Equivalent Elasticity
The restraint stress in stage increases, i.e. t2The stress value at time point subtracts t1' time point the restraint stress increasing value that is worth to of stress
Divided by average elastic modulus is strained with obtaining Equivalent Elasticity in this stage, wherein,
t2-t1Represent the reseting interval time replied in the cycle；
t1’-t1Part represents the Flexible Reset stage；
t2-t1' the part expression Equivalent Elasticity stage.
In the elastic strain calculating method of above-mentioned temperature-stress test, it is determined according to the equivalent age of concrete
2. the specific method of elasticity modulus includes formula；I.e.：
Wherein t0：Presetting period；
te：Equivalent age；
Ect,n：The tensile modulus of elasticity of n days；
nE：Characterize the coefficient of tensile modulus of elasticity development；
s：Constant.
In the elastic strain calculating method of above-mentioned temperature-stress test, the meter of the equivalent age of the concrete
Calculation method for formula 3., the computational methods of the equivalent age after sliding-model control for formula 4., i.e.,：
Wherein, teFor equivalent age, h；T (τ) is the curing temperature course of concrete, DEG C；TiThe corresponding maintenance of-i moment
Temperature, DEG C；Δti- time interval；R is ideal gas constant, R=8.314J/ (molK)；EaFor apparent activation energy, KJ/
mol。
During T >=20 DEG C, Ea(T)/R=Ar；
T<At 20 DEG C, Ea(T)/R=Ar+Br(20-T)
In formula, ArAnd BrFor parameter, obtained by testing.Result of study show the activation energy of hydrated reaction of cement 0~
Generally it is a constant between 100 DEG C.In the case of no test data, it may be assumed that the apparent activation energy of concrete is about
33.5KJ/mol。
In the elastic strain calculating method of above-mentioned temperature-stress test, in step C, in the reply cycle
Elastic strain calculate method for formula 5., i.e.,
S=m1+e1 is 5.
Wherein, S：The elastic strain of one reply cycle inner concrete；
m1：Flexible Reset strains；
e1：Equivalent Elasticity strains.
Elastic strain calculation system in a kind of temperature-stress test using the method for the present invention, including with test specimen template phase
Even and the pilot system with data processing and store function, the pilot system should including being all connected to reply cycle elasticity
Become parameter input module, Flexible Reset strain calculation module and the Equivalent Elasticity strain calculation module of computing module, described returns
Multiple cycle elastic strain calculates module and is also associated with test specimen elastic strain calculating module, wherein：
Test specimen template：Elasticity for the concreting made to be tried to achieve to test specimen by testing machine system afterwards wherein should
Become；
Parameter input module：For inputting pre-determined parameter；
Flexible Reset hardware computing module：For calculating the elastic strain of Flexible Reset stage test specimen；
Equivalent Elasticity strain calculation module：Equivalent Elasticity for calculating Equivalent Elasticity stage test specimen strains；
Reply elastic strain in the cycle and calculate module：For calculating an elastic strain for replying test specimen in the cycle；
Test specimen elastic strain calculates module：For calculating the elastic strain of test specimen in whole age.
Through the above technical solutions, elastic strain is divided into " strain that collet resets generation "+" reseting interval by the present invention
Equivalent Elasticity caused by the development of period internal stress strains " calculate method to provide accurate elastic strain.
The present invention has the following advantages compared to the prior art：1st, principle is simple, calculates quick；2nd, it is easy to operate, framework
Simply；3rd, result of the test is accurate, application is extensive.
Brief description of the drawings
Fig. 1 is the flow chart of the method for the present invention；
Fig. 2 is the system block diagram using the system of the method for the present invention；
Fig. 3 is the principle schematic that the present invention one replys the stress of constraint test specimen in the cycle；
Fig. 4 is that the principle of the stress and strain of gained constraint test specimen in temperature-pressure tester operational process of the present invention is shown
It is intended to；
Fig. 5 is the elastic strain progress curve of the present invention two kinds of concrete under adiabatic model；
Fig. 6 is the elastic strain progress curve of the present invention two kinds of concrete under TMC patterns；
Fig. 7 is the-shrinkage ratio progress curve of creeping of the present invention two kinds of concrete under adiabatic model；
Fig. 8 is the-shrinkage ratio progress curve of creeping of the present invention two kinds of concrete under TMC patterns.
In figure, test specimen template 1；Parameter input module 22；Flexible Reset strain calculation module 21；Equivalent Elasticity strain calculation
Module 23；Reply elastic strain in the cycle and calculate module 25；Test specimen elastic strain calculates module 24.
Embodiment
It is the preferred embodiment of the present invention and with reference to attached drawing below, technical scheme is further described,
But the present invention is not limited to these embodiments.
As shown in Figure 1, the elastic strain that test specimen is constrained in the temperature-stress test of the present invention calculates method, including it is following
Step, wherein step A and step B can be carried out synchronously；
Alternatively, first carrying out step A, then carry out step B；
Alternatively, first carrying out step B, then carry out step A；
The present embodiment is first to carry out step A, then carries out step B and be specifically described：
A：Flexible Reset stage collet is obtained by testing machine and resets the Flexible Reset produced strain；
Wherein it is as follows to obtain the method that Flexible Reset strains for testing machine：
As shown in Figure 3 and Figure 4, by Flexible Reset strain calculation method according to stepper motor in t1’-t1Flexible Reset
Carried out in stage reset generation displacement try to achieve Flexible Reset strain, Flexible Reset strain calculation method for formula 1., i.e.,
M1=n/L is 1.
Wherein, n：Test specimen is in t1’-t1Reset limit value in the Flexible Reset stage；
L：The effective length of test specimen；
m1：In t1’-t1The Flexible Reset stage in collet reset the strain, that is, Flexible Reset strain produced.
B：The development of reseting interval Equivalent Elasticity stage, internal stress period is obtained by Equivalent Elasticity strain calculation method to lead
The Equivalent Elasticity strain of cause；
Wherein, Equivalent Elasticity strain calculation method comprises the following steps：Its bullet is first determined according to the equivalent age of concrete
Property modulus, then according to the restraint stress in Equivalent Elasticity stage increase, i.e. t2The stress value at time point subtracts t1' time point should
The restraint stress increasing value divided by average elastic modulus is strained with obtaining Equivalent Elasticity in this stage that force value obtains, wherein,
t2-t1Represent the reseting interval time replied in the cycle；
t1’-t1Part represents the Flexible Reset stage；
t2-t1' the part expression Equivalent Elasticity stage.
And determine 2. the specific method of its elasticity modulus includes formula according to the equivalent age of concrete；I.e.：
Wherein t0：Presetting period；
te：Equivalent age；
Ect,n：The tensile modulus of elasticity of n days；
nE：Characterize the coefficient of tensile modulus of elasticity development；
s：Constant.
The tensile modulus of elasticity E of wherein n daysct,nMeasured through experiment of machanics, and characterize the coefficient of tensile modulus of elasticity development
NE and constant s is obtained by the tensile elasticity bullet modulus combination common knowledge measured.
Under normal circumstances, the computational methods of the equivalent age of concrete for formula 3., the equivalent age after sliding-model control
The computational methods of phase for formula 4., i.e.,：
Wherein, teFor equivalent age, h；T (τ) is the curing temperature course of concrete, DEG C；TiThe corresponding maintenance of-i moment
Temperature, DEG C；Δti- time interval；R is ideal gas constant, R=8.314J/ (molK)；EaFor apparent activation energy, KJ/
mol。
During T >=20 DEG C, Ea(T)/R=Ar；
T<At 20 DEG C, Ea(T)/R=Ar+Br(20-T)
In formula, ArAnd BrFor parameter, obtained by testing.Result of study show the activation energy of hydrated reaction of cement 0~
Generally it is a constant between 100 DEG C.In the case of no test data, it may be assumed that the apparent activation energy of concrete is about
33.5KJ/mol。
Concrete can be calculated corresponding to the equivalent age under 20 DEG C of standard curings and actual age using above-mentioned formula
Between relation.
C：With reference to the Flexible Reset strain obtained in step A and the Equivalent Elasticity strain obtained in step B by replying week
Elastic strain calculates method and obtains the elastic strain of a reply cycle inner concrete in phase, then by the bullet in each reply cycle
Property the cumulative elastic strain for trying to achieve constraint test specimen of strain, specifically, reply elastic strain in the cycle and calculate method as formula 5., i.e.,
S=m1+e1 is 5.
Wherein, S：The elastic strain of one reply cycle inner concrete；
m1：Flexible Reset strains；
e1：Equivalent Elasticity strains.
As shown in Fig. 2, a kind of elastic strain gage based on constraint test specimen in temperature-stress test using the method for the present invention
The elastic strain of calculation method calculates system, including is connected with test specimen template 1 and has an experiment system of data processing and store function
System 2, pilot system 2 include being all connected to parameter input module 22, the Flexible Reset for replying cycle elastic strain calculating module 25
Strain calculation module 21 and Equivalent Elasticity strain calculation module 23, reply cycle elastic strain calculating module 25 and are also associated with test specimen
Elastic strain calculates module 24, and parameter input module 22 is all connected to Equivalent Elasticity strain calculation module 23, Flexible Reset is answered
Become computing module 21.Wherein：
Test specimen template：Elasticity for the concreting made to be tried to achieve to test specimen by testing machine system afterwards wherein should
Become；
Parameter input module 22：For inputting pre-determined parameter；
Flexible Reset strain calculation module 21：For calculating the elastic strain of Flexible Reset stage test specimen；
Equivalent Elasticity strain calculation module 23：Equivalent Elasticity for calculating Equivalent Elasticity stage test specimen strains；
Reply elastic strain in the cycle and calculate module 25：For calculating an elastic strain for replying test specimen in the cycle；
Test specimen elastic strain calculates module 24：Bullet for the constraint test specimen for calculating temperature-stress test in whole age
Property strain.
As shown in Fig. 5 to Fig. 8, here is the experiment process to concrete：
1st, raw material and match ratio are tested
This experiment prepare two kinds of concrete, " normal concrete " using dome dam A dam concrete raw material and
Match ratio, two kinds of different doping quantity of fly ash concrete " normal concrete " (35% doping quantity of fly ash) and " superelevation adding Concrete "
(80% doping quantity of fly ash).The raw material of experiment are the raw material that dome dam A is used：Magnificent new common 42.5 portland cement,
Jingmen III level flyash, fine aggregate are artificial sand, and coarse aggregate is the artificial rubble of maximum diameter of aggrogate 40mm.Its match ratio is shown in
Table 1：
The match ratio of 1 two kinds of flyash concretes of table
2nd, in the concrete of two kinds of content fly ash of laboratory mixing, by the template of the good concreting of mixing to test specimen
In, parameter has been determined in advance in input, proceeds by experiment, and ensures that experiment is normally carried out up to off-test, measured by export
Data.
3rd, elastic stage (t1 '-t1)：
If reset limit value of the test specimen in t1 '-t1 is n microns, then corresponding to test specimen strain, (m1=n/1.5, test specimen have for m1
Effect length is 1.5m)；It is m so in the Flexible Reset strain of t1 '-t1 stage test specimens1。
4th, the Equivalent Elasticity stage：
Its elasticity modulus can determine that according to the maturity (equivalent age) of concrete.First calculate equivalent age te, then pass through
2. t is calculated in formula1' to the equivalent elastic modulus in t2 stages, the restraint stress for passing through the stage increases (i.e. t2Stress subtract
t1' stress) divided by average elastic modulus calculate Equivalent Elasticity strain e1.The present invention is using Kanstad improvement elasticity modulus hairs
Model is opened up, model is as follows：
Wherein t0：Presetting period；
te：Equivalent age；
Ect,28：The tensile modulus of elasticity of 28 days；
nE：The coefficient of tensile modulus of elasticity development is characterized, the present invention takes 0.4；
s：Constant, normal concrete take 0.25, and superelevation concrete adulterated with fly ash is taken as 0.35.
28 days elasticity modulus of normal concrete and superelevation concrete adulterated with fly ash are measured by mechanical test, are respectively
24.0GPa and 27.8GPa.
3. 4. the equivalent age calculation formula of concrete, is changed into formula for formula after sliding-model control：
Wherein, teFor equivalent age, h；T (τ) is the curing temperature course of concrete, DEG C；TiThe corresponding maintenance of-i moment
Temperature, DEG C；Δti- time interval；R is ideal gas constant, R=8.314J/ (molK)；EaFor apparent activation energy, KJ/
mol。
During T >=20 DEG C, Ea(T)/R=Ar；
T<At 20 DEG C, Ea(T)/R=Ar+Br(20-T)
In formula, ArAnd BrFor parameter, obtained by testing.Result of study show the activation energy of hydrated reaction of cement 0~
Generally it is a constant between 100 DEG C.In the case of no test data, it may be assumed that the apparent activation energy of concrete is about
33.5KJ/mol。
5th, an elastic strain replied in the cycle
The elastic strain of one adjustment cycle inner concrete is equal to its elastic part m1Plus its Equivalent Elasticity part e1。
6th, the elastic strain in whole age calculates
The elastic strain in each adjustment cycle is added up and tries to achieve the elastic strain of constraint test specimen.
Creep-shrinkage ratio is expressed as the ratio of tensile creep and free shrink deformation, freely answering for free test specimen of creeping
Become the elastic strain for subtracting constraint test specimen.Creep-shrinkage ratio can describe the degree of stress relaxation in concrete, ratio more it is big then by
It is bigger to constrain the degree of stress relaxation in test specimen, generally in 0.5~0.8.And the HYPY-TSTM- I of Hang Yuanpingyang companies production
The temperature-stress test that type temperature-pressure tester carries out, the elastic strain for the constraint test specimen that discovery system provides are substantially inclined
It is small, what elastic strain was tried to achieve accordingly creep-and shrinkage ratio is even as high as 0.98, and deviation is too big.The present invention can be in Hang Yuanpingyang companies
In the data and existing theoretical foundation that the I type temperature-pressure testers of HYPY-TSTM- of production are measured, there is provided accurately
Elastic strain calculates method, and for the creeping of the concrete tried to achieve according to the present invention-shrinkage ratio in 0.5~0.8, experiment shows should
With good.Certainly, elastic strain proposed by the invention calculates the HYPY- that new method is applicable not only to the production of Hang Yuanpingyang companies
I type temperature-pressure testers of TSTM-, are equally applicable to other kinds of temperature-pressure tester.
The present invention only needs to ask the Flexible Reset stage of concrete in temperature-stress test plus its Equivalent Elasticity stage
Obtain one and reply elastic strain in the cycle, then the elastic strain in each reply cycle adds up and tries to achieve constraint test specimen
Elastic strain, has the advantages that principle is simple, easy-to-understand, calculating is quick, method is accurate, application is wide.
Specific embodiment described in the present invention is only to spirit explanation for example of the invention.Technology belonging to the present invention is led
The technical staff in domain can make various modifications or supplement to described specific embodiment or substitute in a similar way, but simultaneously
The spirit or beyond the scope of the appended claims of the present invention is not deviated by.
Content described in this specification embodiment is only enumerating to the way of realization of inventive concept, protection of the invention
Scope is not construed as being only limitted to the concrete form that embodiment is stated, protection scope of the present invention is also and in art technology
Personnel conceive according to the present invention it is conceivable that equivalent technologies mean.
Claims (9)
1. the elastic strain that test specimen is constrained in a kind of temperature-stress test calculates method, comprise the following steps：
A：The Flexible Reset that test specimen produces when Flexible Reset stage collet resets is obtained by testing machine to strain；
B：Equivalent Elasticity caused by obtaining the development of Equivalent Elasticity stage internal stress by Equivalent Elasticity strain calculation method strains；
C：Strained with reference to the Flexible Reset strain obtained in step A and the Equivalent Elasticity obtained in step B by replying in the cycle
Elastic strain calculates method and obtains the elastic strain of a reply cycle inner concrete, then should by the elasticity in each reply cycle
Become the cumulative elastic strain for trying to achieve constraint test specimen.
2. elastic strain calculation method in temperature-stress test according to claim 1, it is characterised in that the step
Rapid A and step B is synchronously carried out, or exchange sequence.
3. elastic strain calculation method in temperature-stress test according to claim 2, it is characterised in that in step A
In, the method that testing machine obtains Flexible Reset strain is as follows：
By Flexible Reset strain calculation method according to stepper motor in t1’-t1The Flexible Reset stage in try to achieve the reset of test specimen
Elastic strain, i.e. collet reset the strain produced, its value is t1' and t12 points of strain differential.
4. elastic strain calculation method in temperature-stress test according to claim 3, it is characterised in that the reset
Elastic strain calculate method for formula 1.：
M1=n/L is 1.
Wherein, n：Test specimen is in t1’-t1Reset limit value in the Flexible Reset stage；
L：The effective length of test specimen；
m1：In t1’-t1The Flexible Reset stage in collet reset produce test specimen strain be Flexible Reset strain.
5. elastic strain calculation method in temperature-stress test according to claim 4, it is characterised in that in step B
In, the Equivalent Elasticity strain calculation method comprises the following steps：Its springform is first determined according to the equivalent age of concrete
Amount, then increases, i.e. t according to the restraint stress in Equivalent Elasticity stage2The stress value at time point subtracts t1' time point stress value
Obtained restraint stress increasing value divided by this stage average elastic modulus to obtain Equivalent Elasticity strain, wherein,
t2-t1Represent the reseting interval time replied in the cycle；
t1’-t1Part represents the Flexible Reset stage；
t2-t1' the part expression Equivalent Elasticity stage.
6. elastic strain calculation method in temperature-stress test according to claim 5, it is characterised in that according to coagulation
The equivalent age of soil determines 2. the specific method of its elasticity modulus includes formula；I.e.：
Wherein t0：Presetting period；
te：Equivalent age；
Ect,n：The tensile modulus of elasticity of n days；
nE：Characterize the coefficient of tensile modulus of elasticity development；
s：Constant.
7. elastic strain calculation method in temperature-stress test according to claim 6, it is characterised in that：Described is mixed
3. and 4. the computational methods of the equivalent age of soil are coagulated for formula, i.e.,：
Wherein, teFor equivalent age, h；T (τ) is the curing temperature course of concrete, DEG C；Ti- i moment corresponding curing temperature,
℃；Δti- time interval；R is ideal gas constant, R=8.314J/ (molK)；EaFor apparent activation energy, KJ/mol.
During T >=20 DEG C, Ea(T)/R=Ar；
T<At 20 DEG C, Ea(T)/R=Ar+Br(20-T)
In formula, ArAnd BrFor parameter, obtained by testing.Result of study shows the activation energy of hydrated reaction of cement at 0~100 DEG C
Between be generally constant.In the case of no test data, it may be assumed that the apparent activation energy of concrete is about 33.5KJ/
mol。
8. elastic strain calculation method in temperature-stress test according to claim 7, it is characterised in that in step C
In, in the reply cycle elastic strain calculate method for formula 5., i.e.,
S=m1+e1 is 5.
Wherein, S：The elastic strain of one reply cycle inner concrete；
m1：Flexible Reset strains；
e1：Equivalent Elasticity strains.
9. the elastic strain that test specimen is constrained in a kind of temperature-stress test based on described in claim 1-8 any one calculates
The computing system of method, it is characterised in that：Including being connected and having data processing and the experiment of store function with test specimen template (1)
System (2), the pilot system (2) include being all connected to reply the parameter input mould that cycle elastic strain calculates module (25)
Block (22), Flexible Reset strain calculation module (21) and Equivalent Elasticity strain calculation module (23), reply cycle elasticity
Strain calculation module (25) is also associated with test specimen elastic strain and calculates module (24), wherein：
Test specimen template (1)：Elasticity for the concreting made to be tried to achieve to test specimen by testing machine system afterwards wherein should
Become；
Parameter input module (22)：For inputting pre-determined parameter；
Flexible Reset strain calculation module (21)：For calculating the elastic strain of Flexible Reset stage test specimen；
Equivalent Elasticity strain calculation module (23)：Equivalent Elasticity for calculating Equivalent Elasticity stage test specimen strains；
Reply elastic strain in the cycle and calculate module (25)：For calculating an elastic strain for replying test specimen in the cycle；
Test specimen elastic strain calculates module (24)：For calculating the elastic strain of test specimen in whole age.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711138839.1A CN107977544B (en) | 2017-11-16 | 2017-11-16 | Elastic strain calculation method and system for constraint test piece in temperature-stress test |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711138839.1A CN107977544B (en) | 2017-11-16 | 2017-11-16 | Elastic strain calculation method and system for constraint test piece in temperature-stress test |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107977544A true CN107977544A (en) | 2018-05-01 |
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