CN107976531A - A kind of method for measuring concrete overall process temperature stress - Google Patents
A kind of method for measuring concrete overall process temperature stress Download PDFInfo
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Abstract
A kind of method for measuring concrete overall process temperature stress, concrete raw material is stirred according to corresponding proportioning, is poured into accommodating space, is formed test specimen, cover temperature template upper cover；Temperature sensor is inserted into respectively in the middle part of test specimen in trisection point, and environmental cabinet thermometer hole；Installation displacement sensor in the middle part of test specimen, and fixed with positioning tool, keep its position constant；Corresponding temperature and constrained parameters are set, positioning tool is removed after concrete final set；A displacement varying thresholds are preset, in temperature changing process, concrete sample, which produces, to expand with heat and contract with cold, when its deformation reaches the threshold value of setting, computer control system runs displacement control system according to setting, this deformation is reduced, until concrete sample recovers former long；For concrete sample during former length is recovered, it is pressurized or tension, produces stress increment；With the development that concrete temperature changes, concrete stress also adds up constantly.
Description
Technical field
The invention belongs to the technical field of hydraulic and hydroelectric engineering, particularly a kind of measurement concrete overall process temperature stress
Method.
Background technology
The crack problem of mass concrete always perplexs an important problem of domestic and international project circle, distress in concrete
Appearance, not only affect the presentation quality of structure, also drastically influence the service life and safety of engineering, and then threaten people
The lives and properties of the people.Therefore, the possibility for how avoiding the generation in crack or reducing crack generation just becomes engineering construction person institute
Concern, particularly large volume concrete structural, thermal cracking is main crack form.Up to now, to large volume
The thermal cracking of concrete prevents from mainly in terms of following three setting about：(1) optimised coagulation soil structure, improves mechanical characteristic；(2) material
Improved in terms of material, optimised coagulation soil match ratio, improve the material property of concrete, it is true to grasp concrete heat mechanical characteristic；(3)
Working measure is taken, reduces concrete temperature, prevents concrete from producing the excessive temperature difference.
For hydraulic large-volume concrete, temperature stress is a primary load, and produces the main of thermal cracking
Reason.At present, water conservancy project bound pair is mainly obtained in concrete for hydraulic structure temperature stress by simulation calculation, by many parameter authenticities
Influence, it is difficult true reflection engineering practice；Stress is also to observe data according to concrete strain gauge etc., and process is a series of
Formula obtain temperature stress indirectly, influenced by empirical equation and many intermediate parameters, the temperature stress calculated is difficult anti-
Engineering practice is reflected, drastically influence the decision-making of engineering construction person, in addition, the temperature stress that formula calculates, and it is several
The temperature stress of age, is not the temperature stress process of overall process.Therefore, it is a kind of to measure concrete overall process temperature stress
Apparatus and method just become needed for engineering.
The content of the invention
The object of the present invention is to provide a kind of method for measuring concrete overall process temperature stress, it can improve existing water
The limitation and deficiency of work concrete overall process temperature stress test method, to full mistake of the concrete under temperature change development condition
Journey temperature stress is tested, and is produced to grasp mechanical performance of concrete and crack preventing and is provided reliable basis.
To achieve the above object, the present invention takes following technical scheme：
A kind of method for measuring concrete overall process temperature stress, it utilizes an experimental rig, which includes
One base, an environmental cabinet for being used to completely cut off external environment is provided with the base, is housed in the environmental cabinet equipped with concrete sample
Device；
The concrete sample accommodating device includes fixed chuck, active chuck, two side templates, and split forms a upper end
The open accommodating space of open or upper and lower side, the fixed chuck are fixed at the environmental cabinet one end, which can
The environmental cabinet other end is movably arranged at along the axis of the length direction of the accommodating space, and two side templates are parallel, and to be placed in this solid
Between clamp head and active chuck；The environmental cabinet or the environmental cabinet and the accommodating space set temperature sensor and humidity sensor
Device；The environmental cabinet and concrete sample accommodating device are additionally provided with temperature-adjusting device and humidity control apparatus；
Further include a loading system；The loading system includes a reaction frame, a transmission device and one carries gear reducer
Servomotor, the reaction frame are fixedly installed on the base, which are surrounded；The transmission device includes being arranged on the counter-force
Active leading screw on frame, the active leading screw end connection constraints axis, the constraint axis are worn and the work through the environmental cabinet and end
Dynamic collet connection, and the active chuck position is fixed or is moved in the axis direction；The servomotor and the active leading screw
Connection；Measurement top is equipped with the top of the constraint axis, displacement sensor is equipped between the measurement top and the environmental cabinet；The transmission device is set
There is strain gauge；
The temperature sensor, humidity sensor, displacement sensor, strain gauge are connected to the input of Measurement and Control System
End, the temperature-adjusting device, humidity control apparatus and the servomotor are connected to the output terminal of Measurement and Control System；
Concrete raw material is stirred according to corresponding proportioning, is poured into the accommodating space, is formed test specimen, cover temperature template
Upper cover；Temperature sensor is inserted into respectively in the middle part of test specimen in trisection point, and environmental cabinet thermometer hole；Installation displacement in the middle part of test specimen
Sensor, and fixed with positioning tool, keep its position constant；Corresponding temperature and constrained parameters are set, treat concrete final set
After remove positioning tool；
A displacement varying thresholds Δ L is preset, in temperature changing process, concrete sample produces the α that expands with heat and contract with cold
Δ T L, when its deformation reaches the threshold value of setting (formula 1), computer control system runs displacement control system according to setting,
This deformation is reduced, until concrete sample recovers former long；
α Δ T L=Δs L (1)
α be concrete thermal coefficient of expansion, 10-6/ DEG C；Δ T is the temperature change of concrete；L is the mark of concrete sample
Standard length；Δ L is the concrete sample displacement varying thresholds of setting.
For concrete sample during former length is recovered, it is pressurized or tension (corresponding to temperature rise and temperature drop respectively), produces
Stress increment Δ σ；
With the development that concrete temperature changes, concrete stress also adds up constantly, and concrete overall process temperature should
Power is formed such as formula (2)：
σ is concrete overall process temperature stress；Δ σ is the stress increment often reached when returning to former long after displacement threshold value；n
For the stress increment number in overall process.
Further, it is additionally provided with the environmental cabinet in solar radiation sensor, rainfall sensor and air velocity transducer
At least one, is respectively connected to the input terminal of the Measurement and Control System；Solar radiation tune is also correspondingly provided with the environmental cabinet
At least one of regulating device, rainfall regulating device and wind-speed adjusting device, are respectively connected to the defeated of the Measurement and Control System
Outlet；In measurement process, according to the actual change situation of construction ground illumination, rainfall and wind-force, pass through Measurement and Control System tune
Save solar radiation, rainfall and the wind speed in environmental cabinet.
Further, before the test specimen is poured, " work " font is set between the fixed chuck and active chuck
Locating piece, the both ends of the locating piece are fixedly connected with fixed chuck with active chuck by positioning pin respectively；And pouring examination
The locating piece is removed when 3 is small after part.
Further, in the method, for the simulation of true environment, using at least one in following steps：
1. environment temperature
Depending on local situation, that is, the locality of true environment is simulated, above monthly mean temperature data is fitted to one
Bar cosine curve, following formula (3) are the calculation formula after fitting：
In formula, TaFor temperature, TamFor average temperature of the whole year, AaFor temperature year luffing, τ is the time (moon), τ0For maximum temperature
Time (moon).
Consider temperature diurnal variation, calculated using following formula (4)：
In formula,For daily temperature, TaFor monthly mean temperature, A is temperature diurnal variation amplitude, at the time of t is in 1 day (when) root
Depending on the Various Seasonal of different regions；
2. solar radiant heat
For concrete structure often under solar radiation, it has a major impact concrete temperature.Unit
The heat that solar radiation comes on unit area in time is S, wherein the part by concrete absorption is set as R, remainder quilt
Reflect away, then：
R=αs S (5)
In formula, αsFor absorption coefficient, also referred to as coefficient of blackness, concrete surface generally takes 0.65.
S=S0(1 kn) (6)
In formula, S0For fine day solar radiant heat, n is cloud amount, and k is coefficient, these three numerical value can be provided by local weather station.
The influence of sunshine increases Δ T equivalent to the temperature of surrounding aira,
ΔTa=R/ β (7)
In formula, β is concrete surface exothermic coefficient, can be calculated according to surface roughness and wind speed.
3. precipitation
The precipitation of engineering location meteorological department is inquired about, by precipitation apparatus and precipitation amount controller come simulated precipitation；
And precipitation is calculated by formula (8),
Ps=Pt{1-exp[-(Ta-Tr)/(Tr-Ts)]2)+, Tr≥Ts
Pr=Pt-Ps (8)
P in formulasFor snowfall, PrFor rainfall, PtFor gross precipitation, TaFor daily mean temperature, TrFor the critical temperature of rainfall,
TsFor the critical temperature of snowfall.
4. wind speed
Inquire about the wind speed of the meteorological department in engineering location, threshold wind velocity simulator, to draw concrete according to wind speed
Surface coefficient of heat transfer.
The beneficial effects of the invention are as follows：The method of present invention measurement concrete overall process temperature stress, it can improve existing
There are the limitation and deficiency of concrete for hydraulic structure overall process temperature stress test method, to concrete in actual environment condition Change and Development
Under the conditions of overall process temperature stress tested, produce that provide can to grasp mechanical performance of concrete and crack preventing
By foundation.
Brief description of the drawings
Fig. 1 is the structure diagram for the experimental provision that the method for present invention measurement concrete overall process temperature stress uses.
Fig. 2 is the enlarged diagram at A in Fig. 1.
Fig. 3 is the structure of the locating piece for the experimental provision that the method for present invention measurement concrete overall process temperature stress uses
Schematic diagram.
Embodiment
Below only with the possible embodiment aspect of the embodiment explanation present invention, but and it is not used to limit the present invention and is intended to protect
Category, first give chat it is bright.
As shown in Figure 1 and Figure 2, the present invention provides a kind of method for measuring concrete overall process temperature stress, it utilizes one
Experimental rig, the experimental rig include a base 1, and an environmental cabinet 2 for being used to completely cut off external environment is provided with the base 1, should
Concrete sample accommodating device is equipped with environmental cabinet 2.
The concrete sample accommodating device includes 4, two fixed chuck 3, active chuck side templates 5, and split forms one
The accommodating space that upper end is open or upper and lower side is open, the fixed chuck 3 are fixed at 2 one end of environmental cabinet, the activity
Collet 4 can be movably arranged at 2 other end of environmental cabinet along the axis of the length direction of the accommodating space, and two side templates 5 are flat
Row is placed between the fixed chuck 3 and active chuck 4.The environmental cabinet 2 or the environmental cabinet 2 and the accommodating space set temperature pass
Sensor and humidity sensor.The environmental cabinet 2 and concrete sample accommodating device are additionally provided with temperature-adjusting device and humidity regulation dress
Put.
The experimental provision further includes a loading system.The loading system includes a reaction frame 6, a transmission device and a band
There is the servomotor 7 of gear reducer, which is fixed on the base 1, which is surrounded.The transmission device
Including the active leading screw on the reaction frame 6, the active leading screw end connection constraints axis 8, which passes through the environment
Case 2 and end are worn to be connected with the active chuck 4, and causes 4 position of active chuck to fix or moved in the axis direction.This is watched
Motor 7 is taken to be connected with the active leading screw.The top of constraint axis 8 is equipped with measurement top 9, is equipped between the measurement top 9 and the environmental cabinet
Displacement sensor 10, the transmission device are equipped with strain gauge 11.
The temperature sensor, humidity sensor, displacement sensor 10, strain gauge 11 are connected to Measurement and Control System
Input terminal, the temperature-adjusting device, humidity control apparatus and the servomotor 7 are connected to the output terminal of Measurement and Control System.
In order to keep test specimen consistent, as shown in figure 3, before the test specimen is poured, set between the fixed chuck 3 and active chuck 4
The locating piece 12 of " work " font, the both ends of the locating piece are fixed with fixed chuck 3 and active chuck 4 by positioning pin respectively to be connected
Connect.And the locating piece 12 is removed when after pouring test specimen 3 is small.
During measurement, concrete raw material is stirred according to corresponding proportioning, is poured into the accommodating space, is formed test specimen, cover
Temperature template upper cover；Temperature sensor is inserted into respectively in the middle part of test specimen in trisection point, and environmental cabinet thermometer hole；In the middle part of test specimen
Displacement sensor is installed, and is fixed with positioning tool, keeps its position constant；Corresponding temperature and constrained parameters are set, wait to mix
Positioning tool is removed after solidifying soil final set；
A displacement varying thresholds Δ L is preset, in temperature changing process, concrete sample produces the α that expands with heat and contract with cold
Δ T L, when its deformation reaches the threshold value of setting (formula 1), computer control system runs displacement control system according to setting,
This deformation is reduced, until concrete sample recovers former long；
α Δ T L=Δs L (1)
α be concrete thermal coefficient of expansion, 10-6/ DEG C；Δ T is the temperature change of concrete；L is the mark of concrete sample
Standard length；Δ L is the concrete sample displacement varying thresholds of setting.
For concrete sample during former length is recovered, it is pressurized or tension (corresponding to temperature rise and temperature drop respectively), produces
Stress increment Δ σ；
With the development that concrete temperature changes, concrete stress also adds up constantly, and concrete overall process temperature should
Power is formed such as formula (2)：
σ is concrete overall process temperature stress 1；Δ σ is the stress increment often reached when returning to former long after displacement threshold value；
N is the stress increment number in overall process.
For more accurately construction simulation environment, solar radiation sensor, rainfall sensor are additionally provided with the environmental cabinet 2
At least one of with air velocity transducer, the input terminal of the Measurement and Control System is respectively connected to.Also correspondence is set in the environmental cabinet 2
There are at least one of solar radiation regulating device, rainfall regulating device and wind-speed adjusting device, be respectively connected to the measurement control
The output terminal of system processed.In measurement process, according to the actual change situation of construction ground illumination, rainfall and wind-force, pass through measurement
Solar radiation, rainfall and wind speed in control system adjusting ambient case 2.
In the method, for the simulation of true environment, using at least one in following steps：
1. environment temperature
Depending on local situation, that is, the locality of true environment is simulated, above monthly mean temperature data is fitted to one
Bar cosine curve, following formula (3) are the calculation formula after fitting：
In formula, TaFor temperature, TamFor average temperature of the whole year, AaFor temperature year luffing, τ is the time (moon), τ0For maximum temperature
Time (moon).
Consider temperature diurnal variation, calculated using following formula (4)：
In formula,For daily temperature, TaFor monthly mean temperature, A is temperature diurnal variation amplitude, at the time of t is in 1 day (when) root
Depending on the Various Seasonal of different regions；
2. solar radiant heat
For concrete structure often under solar radiation, it has a major impact concrete temperature.Unit
The heat that solar radiation comes on unit area in time is S, wherein the part by concrete absorption is set as R, remainder quilt
Reflect away, then：
R=αs S (5)
In formula, αsFor absorption coefficient, also referred to as coefficient of blackness, concrete surface generally takes 0.65.
S=S0(1 kn) (6)
In formula, S0For fine day solar radiant heat, n is cloud amount, and k is coefficient, these three numerical value can be provided by local weather station.
The influence of sunshine increases Δ T equivalent to the temperature of surrounding aira,
ΔTa=R/ β (7)
In formula, β is concrete surface exothermic coefficient, can be calculated according to surface roughness and wind speed.
3. precipitation
The precipitation of engineering location meteorological department is inquired about, by precipitation apparatus and precipitation amount controller come simulated precipitation；
And precipitation is calculated by formula (8),
Ps=Pt{1-exp[-(Ta-Tr)/(Tr-Ts)]2}+, Tr≥Ts
Pr=Pt-Ps (8)
P in formulasFor snowfall, PrFor rainfall, PtFor gross precipitation, TaFor daily mean temperature, TrFor the critical temperature of rainfall,
TsFor the critical temperature of snowfall.
4. wind speed
Inquire about the wind speed of the meteorological department in engineering location, threshold wind velocity simulator, to draw concrete according to wind speed
Surface coefficient of heat transfer.
Compared with prior art, the present invention there are following advantages：
1st, under the conditions of experimental rig of the present invention can carry out a variety of temperature control measures, concrete from be poured into hardening overall process in
The evolution of its own temperature stress, including temperature stress, drying shrinkage stress, adiabatic temperature rise, thermal coefficient of expansion, elasticity modulus and
The process that the parameter such as creep develops with the time, can also simulate true weather environment, to the temperature stress under the influence of natural cause
Emulated with Cracking Mechanism.The present invention can be arranged as required to different temperature and constraint degree condition, including thermal insulation, constant temperature,
Temperature rise temperature drop process etc. is set, is tested by concrete cracking whole process simulation, tests the overall process temperature stress of concrete.
2nd, experimental rig of the present invention and method, can directly measure the temperature stress in concrete overall process evolution,
Draw the temperature stress of concrete any age.
3rd, experimental rig of the present invention and method, the temperature that can directly measure under the conditions of concrete overall process temperature change should
Power, the temperature stress for any age that draws concrete under temperature change development course.
4th, experimental rig of the present invention and method, can also directly measure the concrete under the influence of varying environment and temperature control measures
Overall process temperature stress, draws the concrete overall process temperature stress under engineering physical condition.
5th, experimental rig of the present invention and method, can also directly measure the concrete under the influence of varying environment and temperature control measures
Overall process temperature stress, draws the concrete overall process temperature stress under engineering physical condition, is hydraulic large-volume concrete
Construction provides reference.
The present invention is limited with the claim.But this is based on, those of ordinary skill in the art can do
Go out a variety of obvious changes or change, all should be within the main spirits and protection domain of the present invention.
Claims (4)
- A kind of 1. method for measuring concrete overall process temperature stress, it is characterised in that it utilizes an experimental rig, the experiment Device includes a base, and an environmental cabinet for being used to completely cut off external environment is provided with the base, concrete is equipped with the environmental cabinet Test specimen accommodating device；The concrete sample accommodating device includes fixed chuck, active chuck, two side templates, and split forms a upper end opening Or the accommodating space that upper and lower side is open, the fixed chuck are fixed at the environmental cabinet one end, which can be along this The axis of the length direction of accommodating space is movably arranged at the environmental cabinet other end, and two side templates are parallel to be placed in the geometrical clamp Between head and active chuck；The environmental cabinet or the environmental cabinet and the accommodating space set temperature sensor and humidity sensor； The environmental cabinet and concrete sample accommodating device are additionally provided with temperature-adjusting device and humidity control apparatus；Further include a loading system；The loading system includes a reaction frame, a transmission device and a servo with gear reducer Motor, the reaction frame are fixedly installed on the base, which are surrounded；The transmission device includes being arranged on the reaction frame On active leading screw, the active leading screw end connection constraints axis, which is worn through the environmental cabinet and end and activity folder Head connection, and the active chuck position is fixed or is moved in the axis direction；The servomotor is connected with the active leading screw； Measurement top is equipped with the top of the constraint axis, displacement sensor is equipped between the measurement top and the environmental cabinet；The transmission device is equipped with should Force snesor；The temperature sensor, humidity sensor, displacement sensor, strain gauge are connected to the input terminal of Measurement and Control System, The temperature-adjusting device, humidity control apparatus and the servomotor are connected to the output terminal of Measurement and Control System；Concrete raw material is stirred according to corresponding proportioning, is poured into the accommodating space, is formed test specimen, cover in temperature template Lid；Temperature sensor is inserted into respectively in the middle part of test specimen in trisection point, and environmental cabinet thermometer hole；Installation displacement passes in the middle part of test specimen Sensor, and fixed with positioning tool, keep its position constant；Corresponding temperature and constrained parameters are set, after concrete final set Remove positioning tool；A displacement varying thresholds Δ L is preset, in temperature changing process, concrete sample produces the α Δs T that expands with heat and contract with cold L, when its deformation reaches the threshold value of setting (formula 1), computer control system runs displacement control system according to setting, this A deformation reduces, until concrete sample recovers former long；α Δ T L=Δs L (1)α be concrete thermal coefficient of expansion, 10-6/ DEG C；Δ T is the temperature change of concrete；L is that the standard of concrete sample is grown Degree；Δ L is the concrete sample displacement varying thresholds of setting；For concrete sample during former length is recovered, it is pressurized or tension (corresponding to temperature rise and temperature drop respectively), produces stress Increment Delta σ；With the development that concrete temperature changes, concrete stress also adds up constantly, concrete overall process temperature stress shape Into such as formula (2)：<mrow> <mi>&sigma;</mi> <mo>=</mo> <munderover> <mo>&Sigma;</mo> <mrow> <mi>i</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>n</mi> </munderover> <msub> <mi>&Delta;&sigma;</mi> <mi>i</mi> </msub> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>2</mn> <mo>)</mo> </mrow> </mrow>σ is concrete overall process temperature stress；Δ σ is the stress increment often reached when returning to former long after displacement threshold value；N is complete During stress increment number.
- 2. the method for measurement concrete overall process temperature stress according to claim 1, it is characterised in that the environmental cabinet At least one of solar radiation sensor, rainfall sensor and air velocity transducer are inside additionally provided with, is respectively connected to the measurement The input terminal of control system；Solar radiation regulating device, rainfall regulating device and wind speed tune are also correspondingly provided with the environmental cabinet At least one of regulating device, is respectively connected to the output terminal of the Measurement and Control System；In measurement process, according to construction ground The actual change situation of illumination, rainfall and wind-force, passes through solar radiation, rainfall and the wind in Measurement and Control System adjusting ambient case Speed.
- 3. the method for measurement concrete overall process temperature stress according to claim 1, it is characterised in that described pouring Before test specimen, the locating piece of " work " font, the both ends difference of the locating piece are set between the fixed chuck and active chuck It is fixedly connected with fixed chuck with active chuck by positioning pin；And remove the locating piece when after pouring test specimen 3 is small.
- 4. the method for measurement concrete overall process temperature stress according to claim 1, it is characterised in that in the method In, the simulation for true environment, using at least one in following steps：1. environment temperatureDepending on local situation, that is, the locality of true environment is simulated, monthly mean temperature data is fitted to a cosine song Line, following formula (3) are the calculation formula after fitting：<mrow> <msub> <mi>T</mi> <mi>a</mi> </msub> <mo>=</mo> <msub> <mi>T</mi> <mrow> <mi>a</mi> <mi>m</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>A</mi> <mi>a</mi> </msub> <mi>c</mi> <mi>o</mi> <mi>s</mi> <mfrac> <mi>&pi;</mi> <mn>6</mn> </mfrac> <mfenced open = "(" close = ")"> <mtable> <mtr> <mtd> <mi>&tau;</mi> </mtd> <mtd> <msub> <mi>&tau;</mi> <mn>0</mn> </msub> </mtd> </mtr> </mtable> </mfenced> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>3</mn> <mo>)</mo> </mrow> </mrow>In formula, TaFor temperature, TamFor average temperature of the whole year, AaFor temperature year luffing, τ is the time (moon), τ0For the time of maximum temperature (moon).Consider temperature diurnal variation, calculated using following formula (4)：<mrow> <msubsup> <mi>T</mi> <mi>a</mi> <mi>d</mi> </msubsup> <mo>=</mo> <msub> <mi>T</mi> <mi>a</mi> </msub> <mo>+</mo> <mi>A</mi> <mi>c</mi> <mi>o</mi> <mi>s</mi> <mfrac> <mi>&pi;</mi> <mn>12</mn> </mfrac> <mfenced open = "(" close = ")"> <mtable> <mtr> <mtd> <mi>t</mi> </mtd> <mtd> <mn>14</mn> </mtd> </mtr> </mtable> </mfenced> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>4</mn> <mo>)</mo> </mrow> </mrow>In formula,For daily temperature, TaFor monthly mean temperature, A is temperature diurnal variation amplitude, at the time of t is in 1 day (when) according to not Depending on Various Seasonal with area；2. solar radiant heatThe heat that solar radiation comes on unit area in unit interval is S, wherein setting the part by concrete absorption as R, is remained Remaining part point is reflected, then：R=αs S (5)In formula, αsFor absorption coefficient, concrete surface takes 0.65.S=S0(1 kn) (6)In formula, S0For fine day solar radiant heat, n is cloud amount, and k is coefficient.The influence of sunshine increases Δ T equivalent to the temperature of surrounding aira,ΔTa=R/ β (7)In formula, β is concrete surface exothermic coefficient, is calculated according to surface roughness and wind speed.3. precipitationThe precipitation of engineering location meteorological department is inquired about, by precipitation apparatus and precipitation amount controller come simulated precipitation；And precipitation is calculated by formula (8),Ps=Pt{1-exp[-(Ta-Tr)/(Tr-Ts)]2)+, Tr≥TsPr=Pt-Ps (8)P in formulasFor snowfall, PrFor rainfall, PtFor gross precipitation, TaFor daily mean temperature, TrFor the critical temperature of rainfall, TsFor The critical temperature of snowfall.4. wind speedInquire about the wind speed of the meteorological department in engineering location, threshold wind velocity simulator, to draw concrete surface according to wind speed Coefficient of heat transfer.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711121436.6A CN107976531A (en) | 2017-11-14 | 2017-11-14 | A kind of method for measuring concrete overall process temperature stress |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711121436.6A CN107976531A (en) | 2017-11-14 | 2017-11-14 | A kind of method for measuring concrete overall process temperature stress |
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| CN107976531A true CN107976531A (en) | 2018-05-01 |
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Cited By (3)
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| CN108956688A (en) * | 2018-05-02 | 2018-12-07 | 华南理工大学 | A kind of measuring system and method for building material surface combined radiation absorption coefficient |
| CN108951723A (en) * | 2018-07-20 | 2018-12-07 | 中国三峡建设管理有限公司 | A kind of indoor implementation method of the true constraint degree of large volume concrete structural |
| CN111707530A (en) * | 2020-06-19 | 2020-09-25 | 威胜利工程有限公司 | Test piece for low-temperature anchoring performance test and temperature measurement structure thereof |
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| CN108951723A (en) * | 2018-07-20 | 2018-12-07 | 中国三峡建设管理有限公司 | A kind of indoor implementation method of the true constraint degree of large volume concrete structural |
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| CN111707530A (en) * | 2020-06-19 | 2020-09-25 | 威胜利工程有限公司 | Test piece for low-temperature anchoring performance test and temperature measurement structure thereof |
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