CN116125047A - Cement-based material surface moisture diffusion factor measuring device and measuring method - Google Patents
Cement-based material surface moisture diffusion factor measuring device and measuring method Download PDFInfo
- Publication number
- CN116125047A CN116125047A CN202211553145.5A CN202211553145A CN116125047A CN 116125047 A CN116125047 A CN 116125047A CN 202211553145 A CN202211553145 A CN 202211553145A CN 116125047 A CN116125047 A CN 116125047A
- Authority
- CN
- China
- Prior art keywords
- cement
- based material
- test piece
- measuring
- diffusion factor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000463 material Substances 0.000 title claims abstract description 78
- 239000004568 cement Substances 0.000 title claims abstract description 77
- 238000009792 diffusion process Methods 0.000 title claims abstract description 65
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000012360 testing method Methods 0.000 claims abstract description 86
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 43
- 238000005259 measurement Methods 0.000 claims abstract description 34
- 238000005286 illumination Methods 0.000 claims abstract description 8
- 238000012546 transfer Methods 0.000 claims description 30
- 230000008859 change Effects 0.000 claims description 7
- 230000007613 environmental effect Effects 0.000 claims description 6
- 229920006395 saturated elastomer Polymers 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 238000007789 sealing Methods 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 238000012423 maintenance Methods 0.000 abstract description 3
- 238000011160 research Methods 0.000 abstract description 3
- 238000010561 standard procedure Methods 0.000 abstract description 2
- 238000002474 experimental method Methods 0.000 abstract 1
- 239000002352 surface water Substances 0.000 abstract 1
- 230000008569 process Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 230000004075 alteration Effects 0.000 description 2
- 230000036571 hydration Effects 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 235000019738 Limestone Nutrition 0.000 description 1
- 239000011398 Portland cement Substances 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010881 fly ash Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000006028 limestone Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920005646 polycarboxylate Polymers 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/38—Concrete; Lime; Mortar; Gypsum; Bricks; Ceramics; Glass
- G01N33/383—Concrete or cement
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Medicinal Chemistry (AREA)
- Food Science & Technology (AREA)
- Ceramic Engineering (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses a device and a method for measuring a water diffusion factor on the surface of a cement-based material. The measuring device includes: the system comprises a grating temperature and humidity sensor, an anemometer, a wind vane, an illumination meter, a barometer, an environment temperature and humidity sensor, a test piece quality measurement system and a comprehensive control system. The invention realizes the rapid and effective determination of the water diffusion factor on the surface of the cement-based material, has simple and portable device, convenient and easy operation, can rapidly analyze and display the result, solves the difficult problem of rapid determination of the water diffusion factor on the surface of the cement-based material, provides an important basis for determining the surface water diffusion factor which is a key parameter in the calculation of the humidity field of the cement-based material, provides an important parameter for on-site maintenance of the cement-based material, and has important significance for improving the durability of the cement-based material. The invention is not only suitable for laboratory scientific research experiments and engineering field determination of the water diffusion factor on the surface of the cement-based material, but also can be popularized and applied as a standard device and a standard method.
Description
Technical Field
The invention relates to the technical field of cement-based materials, in particular to a device and a method for measuring a water diffusion factor on the surface of a cement-based material.
Background
The cement-based material is a porous material, and since its internal relative humidity is often higher than the ambient relative humidity, the internal moisture of the cement-based material will continuously diffuse into the environment. Due to the diffusion, the relative humidity inside the cement-based material is continuously reduced, and shrinkage and even cracking of the cement-based material are caused. The important parameter affecting the diffusion speed of the water in the cement-based material to the environment is the water diffusion factor of the cement-based material surface. The accurate determination of the water diffusion factor on the surface of the cement-based material has important significance for calculating the internal humidity field of the cement-based material, making maintenance measures and improving the durability of the cement-based material.
The water diffusion factor on the surface of the cement-based material is related to a plurality of factors such as ambient temperature, ambient humidity, ambient wind speed, ambient air pressure, heat radiation, surface temperature of the cement-based material, surface roughness of the cement-based material and the like, and no accurate theoretical calculation formula exists at present. Because the existing measuring method is limited, the water diffusion factor of the cement-based material surface is generally taken as an empirical value during actual scientific research and engineering calculation, and the actual requirement is difficult to meet, the research and development of a measuring device and a measuring method capable of rapidly, simply, conveniently and accurately measuring the water diffusion factor of the cement-based material surface are needed.
Disclosure of Invention
In order to solve the above problems, an object of the present invention is to provide a device and a method for measuring a cement-based material surface moisture diffusion factor.
The above purpose can be achieved by the following technical scheme:
a cement-based material surface moisture diffusion factor measuring device is characterized in that: comprising the following steps: the system comprises a grating temperature and humidity sensor (1), an anemometer and wind vane (2), an illumination meter (3), a barometer (4), an environment temperature and humidity sensor (5), a quality measurement system (6) and a comprehensive control system (7);
the grating temperature and humidity sensor (1) is used for measuring the surface temperature and relative humidity of the cement-based material, and is attached and fixed on the surface of the cement-based material during measurement;
the anemometer and wind vane (2) is used for measuring the ambient wind speed and wind direction;
the illumination meter (3) is used for measuring the ambient illumination intensity;
the barometer (4) is used for measuring the ambient atmospheric pressure;
the environment temperature and humidity sensor (5) is used for measuring the environment temperature and humidity;
the quality measurement system (6) is used for measuring the quality change of the cement-based material test piece;
the comprehensive control system (7) is used for controlling each measuring system, collecting and storing data, calculating the surface moisture diffusion factor in real time and drawing a curve.
Preferably, each measuring system collects data simultaneously and in real time, and the collection frequency is set by the integrated control system.
Preferably, the mass measurement system (6) comprises: a level (8) for determining whether the quality measurement system is in a level state; and the leveling nut (9) is used for adjusting the level state of the quality measurement system.
Preferably, the accuracy of the mass measurement system (6) is higher than 0.1g, and the upper range limit is higher than 20kg.
Preferably, during measurement, the anemometer and the wind vane (2), the light meter (3), the barometer (4) and the environment temperature and humidity sensor (5) are arranged on two sides of the windward side of the test piece.
Preferably, during measurement, the grating temperature and humidity sensor (1) is firmly fixed with the surface of the cement-based material test piece, and does not influence the quality measurement system (6).
In still another aspect, there is provided a method for measuring a water diffusion factor on a cement-based material surface, comprising the steps of:
s1, preparing a cement-based material test piece, if the test piece is a new pouring test piece, the upper surface of the test piece is flush with the upper surface of a die, and a grating temperature and humidity sensor (1) is fixed and placed on a quality measurement system (6) together; if the test piece is a molded and hardened test piece, grinding the position of the grating temperature and humidity sensor (1) on the surface of the test piece, immersing the test piece in water, taking out the test piece, sealing other surfaces of the test piece except the surface which is partially ground, fixing the grating temperature and humidity sensor (1) on the ground position, and finally placing the test piece on a quality measurement system (6);
s2, installing an anemometer and a wind vane (2), determining the windward side of the test piece according to the wind direction determined by the wind vane, and installing the anemometer and wind vane (2), an illuminometer (3), a barometer (4) and an environment temperature and humidity sensor (5) on two sides of the windward side of the test piece;
s3, after each measuring system is installed, data acquisition is started;
s4, calculating the water diffusion factor of the surface of the cement-based material according to the acquired data, recording the surface area of the cement-based material test piece as S, the saturated water vapor density as rho, and the effective mass transfer area rate of the surface of the test piece as follows
t i The measured data of the moment quality measuring system (6) is m i The relative humidity of the surface of the cement-based material measured by the grating temperature and humidity sensor (1) is H c (t i ) The relative humidity of the environment measured by the environment temperature and humidity sensor (5) is H e (t i ) Sampling time interval is delta t, t 1 For initial acquisition of data time, t n For the nth time of collecting data, selecting t 1 To t n And calculating the water diffusion factor a of the surface of the cement-based material according to the data acquired at the moment and the following formula (1):
preferably, the saturated steam density is obtained by checking a public saturated steam temperature density pressure comparison table from data measured by a barometer (4) and an environment temperature and humidity sensor (5).
Preferably, in early measurement, liquid water exists on the surface of the test piece, and the effective mass transfer area rate of the surface of the test piece
The value of (2) may be considered as 100%; t is t 1 To t n The time interval is longer than 10 minutes and less than 1 hour.
Preferably, the cement-based material surface moisture diffusion factor measuring device can be used for measuring not only the cement-based material surface moisture diffusion factor, but also other solid surface moisture diffusion factors which have moisture diffusion exchange with the environment.
Compared with the prior art, the invention has the following beneficial effects:
(1) The invention realizes the rapid and accurate measurement of the water diffusion factor on the surface of the cement-based material, solves the difficult problem of measuring the water diffusion factor on the surface of the cement-based material, and provides important parameter support for calculating the internal humidity field of the cement-based material, making maintenance measures and improving the durability of the cement-based material;
(2) The measuring device disclosed by the invention can be produced in a standardized way, and is short in measuring time, convenient to carry and simple to operate;
(3) The invention can adopt a formed test piece or a newly poured test piece, thereby being convenient for engineering field operation;
(4) The invention can also reversely calculate the effective mass transfer area rate of the surface of the test piece
Value changes with age;
(5) The invention displays the water diffusion factor curve and the numerical value of the cement-based material surface in real time, is suitable for laboratory scientific research and engineering site use, and can be popularized and applied as a standard device and a standard method.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those of ordinary skill in the art that the drawings in the following description are exemplary only and that other implementations can be obtained from the extensions of the drawings provided without inventive effort.
The structures, proportions, sizes, etc. shown in the present specification are shown only for the purposes of illustration and description, and are not intended to limit the scope of the invention, which is defined by the claims, but rather by the claims.
FIG. 1 is a schematic diagram showing the measurement process of a device for measuring the surface moisture diffusion factor of a cement-based material according to an embodiment of the present invention.
FIG. 2 is a graph showing the effective mass transfer area rate of the surfaces of existing and freshly poured test pieces
Values are plotted against age.
FIG. 3 shows the effective mass transfer area ratio of the water diffusion factor a on the surface of a newly poured test piece and the surface of the test piece
And (5) a change chart of the product along with the age.
FIG. 4 is a graph showing the effective mass transfer area rate of the surface of a freshly poured test piece
And (5) a change chart of the product along with the age.
In the figure: 1. a grating temperature and humidity sensor; 2. anemometer and wind vane; 3. an illumination meter; 4. a barometer; 5. an environmental temperature and humidity sensor; 6. a mass measurement system; 7. a comprehensive control system; 8. a vial; 9. leveling the nut; 10. a test piece mold; 11. and (3) a cement-based material test piece.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the present invention will be described in further detail with reference to the embodiments and the accompanying drawings. The exemplary embodiments of the present invention and their descriptions herein are for the purpose of explaining the present invention, but are not to be construed as limiting the invention.
In the description of the present invention, the terms "comprises/comprising," "consists of … …," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a product, apparatus, process, or method that comprises a list of elements does not include only those elements but may, if desired, include other elements not expressly listed or inherent to such product, apparatus, process, or method. Without further limitation, an element defined by the phrases "comprising/including … …," "consisting of … …," and the like, does not exclude the presence of other like elements in a product, apparatus, process, or method that includes the element.
It is to be understood that unless specifically stated or limited otherwise, the terms "disposed," "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, any suitable arrangement, fixed or removable, or integrated; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
It should be further understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," "center," and the like are used in an orientation or positional relationship based on that shown in the drawings, merely to facilitate describing the present invention and to simplify the description, and do not indicate or imply that the devices, components, or structures referred to must have a particular orientation, be constructed or operated in a particular orientation, and are not to be construed as limiting the present invention.
The implementation of the present invention will be described in detail with reference to the preferred embodiments.
The invention firstly provides a device for measuring the water diffusion factor on the surface of a cement-based material, which is formed by combining the following devices: the device comprises a grating temperature and humidity sensor (1), an anemometer and wind vane (2), an illumination meter (3), a barometer (4), an environment temperature and humidity sensor (5), a quality measuring system (6) and a comprehensive control system (7).
The invention provides a measuring method of a cement-based material surface moisture diffusion factor measuring device, which comprises the following steps:
effective mass transfer area rate of the surface of the test piece in formula (1)
Determination of the values: effective mass transfer area ratio of test piece surface>
The value is related to the age of the cement-based material, the effective mass transfer area of the surface of the test piece is continuously reduced along with the increase of the age and tends to be stable, and the effective mass transfer area rate of the surface of the test piece is +.>
The values are shown schematically as a function of age in figure 2. The liquid water exists on the surface of the test piece just poured or just saturated with water, and the effective mass transfer area rate of the surface of the test piece is +.>
The value can be considered to be 100%, which is why the existing test piece is first saturated with water. As the hydration of the existing test piece is basically finished and the pore structure is basically unchanged, the effective mass transfer area of the surface of the test piece is basically unchanged after the surface moisture is dried, and the effective mass transfer area rate of the surface of the test piece is +.>
The values quickly tend to stabilize. As hydration of the newly poured test piece continuously develops and the surface pore structure of the material also continuously develops after the surface moisture is dried, the effective mass transfer area rate of the surface of the test piece is +.>
The value of the test piece is slower and stable than that of the existing test piece. Actual test data show that the effective mass transfer area rate of the surface of the newly poured test piece is +.>
The values generally gradually stabilize after 1 day.
t 1 To t n And (3) selecting time: due to the effective mass transfer area rate of the surface of the test piece
The value can only be determined to be 100% at the initial moment, and the water diffusion factor a value of the cement-based material surface needs to be accurately determined from the acquisitionStarting calculation at initial moment, i.e. from t 1 The calculation starts at the moment. The water diffusion on the surface of the cement-based material is slower, if t n And t 1 The time interval is too short, the mass change is too small, i.e. (m n -m 1 ) Is too small and takes into account the effects of wind and other vibrations in the engineering site, (m n -m 1 ) Too small a value of (c) may result in too large a mass measurement error. If t n And t 1 The time interval is too long, on the one hand, the effective mass transfer area rate of the surface of the test piece is +.>
The value starts to decrease, so that the calculated value of the surface moisture diffusion factor a is larger; on the other hand, environmental parameters are also constantly changing, resulting in unstable values of the surface moisture diffusion factor a. Proved by practical experimental study, t n And t 1 The time interval is longer than 10 minutes and less than 1 hour, and the calculated value of the surface moisture diffusion factor a is relatively reasonable.
The effective mass transfer area rate of the surface of the test piece is calculated by reverse thrust
Value: because the water diffusion factor on the surface of the cement-based material is irrelevant to the change of the mass transfer area on the surface of the cement-based material, the effective mass transfer area rate of the surface of the early-age test piece can be utilized first>
When the value is 100%, calculating the water diffusion factor of the surface of the cement-based material, and then reversely calculating the effective mass transfer area rate of the surface of the test piece by using the formula (1) and the water diffusion factor value of the surface of the cement-based material>
Value changes with age. Effective mass transfer area ratio of test piece surface>
The value is also one of the important parameters for calculating the internal humidity field of the cement-based material.
It should be noted that the water diffusion factor of the cement-based material surface is also related to the dimension of the test piece in the wind direction. Therefore, the device provided by the invention comprises the device for measuring the wind direction, so that the dimension of the actual engineering structure along the wind direction can be conveniently measured on the engineering site. At present, no accurate theoretical formula is available for calculating the relation between the surface moisture diffusion factor of the cement-based material and the size of a test piece, but it can be determined that the smaller the size of the test piece is, the larger the surface moisture diffusion factor is, namely the largest surface moisture diffusion factor of the windward position is. Therefore, the windward position is the position of the engineering structure surface with the fastest water loss. When in measurement, the surface moisture diffusion factor is measured by using a test piece with smaller size, so that the method has strong engineering practical significance. Of course, according to the measuring principle and the measuring method provided by the invention, the surface moisture diffusion factor of the large-size structure can be measured by using the mass measuring system range of the large range.
Example 1: the raw materials are as follows: p. 042.5 Portland cement, natural sand (fineness modulus is 2.78), crushed limestone (maximum particle diameter is 20 mm), I-level fly ash, polycarboxylate water reducer and water reducing rate of 30%. The concrete mixing ratio is shown in Table 1.
TABLE 1 concrete mix ratio
For relatively long-time observation, an indoor environment with stable environmental conditions is selected for test, and the actual indoor environment parameters are as follows: the ambient temperature is 20-24 ℃, the ambient relative humidity is 40-50%, the wind speed is 0, the air pressure is 100.1-100.5 kPa, and the illumination intensity is 490-500 Lx. The size of a newly poured test piece is 100mm multiplied by 400mm, the sampling frequency of each measuring system is 5 minutes/time, t n And t 1 The time interval is 30 minutes, and the water diffusion factor a of the surface of the newly poured test piece and the effective mass transfer area rate of the surface of the test piece are calculated through test data
Product variation with ageThe figure is shown in figure 3. According to the measurement principle, in the initial stage, the effective mass transfer area rate of the surface of the test piece is +.>
100% by weight, the surface moisture diffusion factor a value of 0.52X10 can be calculated -3 m/s. In fact, the value of the surface moisture diffusion factor a is unchanged due to the relatively stable environmental conditions, and the effective mass transfer area ratio of the surface moisture diffusion factor a and the surface of the test piece is +.>
The trend graph of the product is the effective mass transfer area rate of the surface of the test piece>
Trend chart, back calculation to obtain effective mass transfer area rate of the surface of the test piece>
The change with age is shown in figure 4. As can be seen from FIG. 4, the effective mass transfer area ratio of the test piece surface>
And finally, the stability is about 4%.
The illustrative embodiments have been described above with the understanding that numerous alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to form a part of this disclosure, and are intended to be within the spirit and scope of the invention. Although some examples presented herein refer to particular combinations of functions or structures, it should be understood that these functions and structures may be combined in other ways in accordance with the invention to achieve the same or different objectives. In particular, acts, elements and features discussed in connection with one embodiment are not intended to be excluded from a similar or other role in other embodiments. Furthermore, the structures and components herein may be further divided into additional components or combined together to form fewer components for performing the same functions. Accordingly, the foregoing description and drawings are by way of example only and are not intended to be limiting, and the scope of the invention should be understood and appreciated to cover all such other variations or modifications.
Claims (10)
1. A cement-based material surface moisture diffusion factor measuring device is characterized in that: comprising the following steps: the system comprises a grating temperature and humidity sensor (1), an anemometer and wind vane (2), an illumination meter (3), a barometer (4), an environment temperature and humidity sensor (5), a quality measurement system (6) and a comprehensive control system (7);
the grating temperature and humidity sensor (1) is used for measuring the surface temperature and relative humidity of the cement-based material, and is attached and fixed on the surface of the cement-based material during measurement;
the anemometer and wind vane (2) is used for measuring the ambient wind speed and wind direction;
the light meter (3) is used for measuring the ambient light intensity;
the barometer (4) is used for measuring the ambient atmospheric pressure;
the environment temperature and humidity sensor (5) is used for measuring the environment temperature and humidity;
the quality measurement system (6) is used for measuring the quality change of the cement-based material test piece;
the comprehensive control system (7) is used for controlling each measuring system, collecting and storing data, calculating the surface moisture diffusion factor in real time and drawing a curve.
2. The cement-based material surface moisture diffusion factor measuring device according to claim 1, wherein: each measuring system collects data simultaneously and in real time, and the collection frequency is set by the comprehensive control system.
3. The cement-based material surface moisture diffusion factor measuring device according to claim 1, wherein: the mass measurement system (6) comprises: a level (8) for determining whether the quality measurement system is in a level state; and the leveling nut (9) is used for adjusting the level state of the quality measurement system.
4. The cement-based material surface moisture diffusion factor measuring device according to claim 1, wherein: the accuracy of the mass measurement system (6) is higher than 0.1g, and the upper range limit is higher than 20kg.
5. The cement-based material surface moisture diffusion factor measuring device according to claim 1, wherein: during measurement, the anemometer and wind vane (2), the light meter (3), the barometer (4) and the environmental temperature and humidity sensor (5) are arranged on two sides of the windward side of the test piece.
6. The cement-based material surface moisture diffusion factor measuring device according to claim 1, wherein: during measurement, the grating temperature and humidity sensor (1) is firmly fixed with the surface of the cement-based material test piece, and does not influence the quality measurement system (6).
7. The method for measuring the water diffusion factor of the surface of the cement-based material is characterized by comprising the following steps of:
s1, preparing a cement-based material test piece, if the test piece is a new pouring test piece, the upper surface of the test piece is flush with the upper surface of a die, and a grating temperature and humidity sensor (1) is fixed and placed on a quality measurement system (6) together; if the test piece is a molded and hardened test piece, grinding the position of the grating temperature and humidity sensor (1) on the surface of the test piece, immersing the test piece in water, taking out the test piece, sealing other surfaces of the test piece except the surface which is partially ground, fixing the grating temperature and humidity sensor (1) on the ground position, and finally placing the test piece on a quality measurement system (6);
s2, installing an anemometer and a wind vane (2), determining the windward side of the test piece according to the wind direction determined by the wind vane, and installing the anemometer and wind vane (2), an illuminometer (3), a barometer (4) and an environment temperature and humidity sensor (5) on two sides of the windward side of the test piece;
s3, after each measuring system is installed, data acquisition is started;
s4, calculating the water diffusion factor of the surface of the cement-based material according to the acquired data, recording the surface area of the cement-based material test piece as S, the saturated water vapor density as rho, and the effective mass transfer area rate of the surface of the test piece as follows
t i The measured data of the moment quality measuring system (6) is m i The relative humidity of the surface of the cement-based material measured by the grating temperature and humidity sensor (1) is H c (t i ) The relative humidity of the environment measured by the environment temperature and humidity sensor (5) is H e (t i ) Sampling time interval is delta t, t 1 For initial acquisition of data time, t n For the nth time of collecting data, selecting t 1 To t n And calculating the water diffusion factor a of the surface of the cement-based material according to the data acquired at the moment and the following formula (1):
8. the method according to claim 7, wherein the saturated steam density ρ is obtained from a reference table of the temperature density and pressure of saturated steam obtained by checking the data measured by the barometer (4) and the environmental temperature and humidity sensor (5).
9. The method for measuring the water diffusion factor of a cement-based material surface according to claim 7, wherein in the early stage of the measurement, liquid water is present on the test piece surface, and the effective mass transfer area ratio of the test piece surface is measured
The value of (2) may be considered as 100%; t is t 1 Time selection measurement initial time, t 1 To t n The time interval is longer than 10 minutes and less than 1 hour.
10. The device for measuring the surface moisture diffusion factor of a cement-based material according to claim 1, wherein the device can be used for measuring not only the surface moisture diffusion factor of the cement-based material but also other solid surface moisture diffusion factors which are in water diffusion exchange with the environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211553145.5A CN116125047A (en) | 2022-12-05 | 2022-12-05 | Cement-based material surface moisture diffusion factor measuring device and measuring method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211553145.5A CN116125047A (en) | 2022-12-05 | 2022-12-05 | Cement-based material surface moisture diffusion factor measuring device and measuring method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116125047A true CN116125047A (en) | 2023-05-16 |
Family
ID=86294693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211553145.5A Pending CN116125047A (en) | 2022-12-05 | 2022-12-05 | Cement-based material surface moisture diffusion factor measuring device and measuring method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116125047A (en) |
-
2022
- 2022-12-05 CN CN202211553145.5A patent/CN116125047A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Torrent | A two-chamber vacuum cell for measuring the coefficient of permeability to air of the concrete cover on site | |
| Mejlhede Jensen et al. | A dilatometer for measuring autogenous deformation in hardening Portland cement paste | |
| Johannesson | Dimensional and ice content changes of hardened concrete at different freezing and thawing temperatures | |
| CN108844881B (en) | Method for predicting relative permeability coefficient of unsaturated soil based on VG model | |
| CN103293179B (en) | The early stage thermal expansion coefficient testing device of concrete based on suspension method and method of testing | |
| Lura et al. | Measurement of water transport from saturated pumice aggregates to hardening cement paste | |
| CN106442945B (en) | The test method that a kind of evaluable live fresh concrete layering situation and layering influence maturing | |
| CN101586993A (en) | Concrete early stage frost heave stress test device and test method | |
| CN110865180B (en) | Method and device for testing workability of pervious concrete | |
| CN103499682A (en) | Method for testing early stage shrinkage and anti-cracking performances of premixed concrete wall | |
| CN112858647B (en) | Testing device for inhibiting self-shrinkage effect of cement concrete by water-absorbent resin and evaluation method thereof | |
| CN108107068A (en) | The test method of lightweight aggregate concrete hole icing rate under Frozen-thawed cycled | |
| JP2020051812A (en) | Measuring method of heat expansion coefficient of concrete | |
| Cusson et al. | Measuring early-age coefficient of thermal expansion in high-performance concrete | |
| Zhang et al. | Role of early drying cracks in the shrinkage size effect of cement paste | |
| CN116125047A (en) | Cement-based material surface moisture diffusion factor measuring device and measuring method | |
| Wang et al. | Influence of low vacuum and high temperature condition on moisture transport and dry shrinkage of mature concrete | |
| CN109841266B (en) | Construction method and application of early pore size model of super absorbent resin internal curing cement slurry | |
| CN107643243A (en) | The measure device and method of pervious concrete porosity distribution | |
| CN207336315U (en) | The measurement device of pervious concrete porosity distribution | |
| WO2013097189A1 (en) | Method for testing self-drying effect of cement-based material | |
| CN113176172B (en) | Device and method for measuring surface moisture content of sandstone aggregate | |
| CN107631971B (en) | A kind of saturating sand coefficient rapid assay methods of vegetation form cellular concrete and device | |
| CN215493067U (en) | Test tank structure for detecting shrinkage performance of slag soil fluidized backfill material | |
| CN203772622U (en) | Device for artificially preparing structured intact soft clay test soil sample |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication |