JP2006118996A - Concrete tester and concrete testing method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact concrete tester and a concrete testing method for simply, easily and inexpensively finding various thermal characteristic values so as to accurately calculate a thermal crack index. <P>SOLUTION: The concrete tester is provided with a vessel 1 comprising a vacuum thermal-insulation vessel having a high thermal-insulation performance, a heater 6 for internally heating the vessel 1, a cooling apparatus 16 for using a Peltier element and internally cooling the vessel 1, fans 7, 8 for equalizing a thermal distribution within the vessel 1, a temperature measuring means 10 embedded into a concrete specimen 3 accommodated within the vessel 1, and programmable temperature regulators 12, 13 connected to the temperature measuring means 10, the heaters 7, 8 and the cooling apparatus 16 and regulating the temperature. An adiabatic temperature rising test is implemented by the concrete tester A. A thermal diffusion coefficient test and a thermal capacity test are implemented by using the specimen 3 after the adiabatic temperature rising test. Then, a test for finding a dynamic characteristic value of the specimen 3 having a high-temperature history due to the tests is implemented. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a test apparatus for measuring various characteristic values of concrete and a concrete test method using the same.

  In a structure (mass concrete) having a very large size as represented by a dam, a stress called a temperature stress is generated by the heat of hydration of the cement, which causes a crack (temperature crack). For this reason, mass concrete is required to be designed and constructed in consideration of temperature rise due to heat of hydration. The same phenomenon of temperature cracking occurs due to rapid construction of reinforced concrete structures in recent years, high strength, etc., for example, abutment, pier, retaining wall, culvert, etc. The number of structures that must be handled as mass concrete is increasing.

  Conventionally, for temperature cracks in reinforced concrete structures, there is no uniform guideline or standard for suppressing cracks, and each site is planned and constructed. Even when cracks occur, the current situation is that they are being examined individually, especially for large cracks that may have an impact on durability.

  However, in recent years, there has been an increasing number of cases in which the transition to the performance check-type instruction manual is performed and temperature cracks are checked not only at the design stage but also at the construction planning stage. In the calculation of the temperature cracking index, uncertain parameters such as the outside air temperature and sunshine conditions at the time of placing are used in many cases, but various thermal characteristic values of the input concrete often use estimated values. If there is a large difference between the estimated thermal characteristic value and the actual thermal characteristic value, a large error occurs in the calculation result of the temperature cracking index. According to the specifications, various thermal characteristic values are obtained by testing, but the constants related to the ultimate adiabatic temperature rise and the rate of temperature rise are the same as in the past, except when examining large-scale or special structures. Most cases are obtained from data and estimation formulas. Furthermore, for thermal conductivity and mechanical property values, there are no accurate estimation formulas (especially, strength estimation formulas for concrete subjected to high-temperature history), and there are few existing data, so estimations with little decision base. It seems that there are many cases using. In addition, when using special cements, admixtures, and blends (see, for example, Patent Documents 1 and 2), it is difficult to determine an estimated value from existing data, and it is obtained by testing as shown in the specifications. There is a need.

  Thermal properties tests for concrete structures include adiabatic temperature rise test, thermal diffusion coefficient test, and heat capacity test, and test specimens for which all tests have been completed are tested for strength property values as concrete subjected to high temperature history. . As an adiabatic temperature rise test apparatus, there exist some which were indicated by patent documents 3-6, for example.

  Patent Document 3 discloses an adiabatic temperature rise test apparatus including a test tank in which a heat medium jacket for storing a specimen is provided, and a heat insulating chamber surrounded by a heat insulating wall surface that maintains the test tank in a heat insulating state, An adiabatic temperature rise test apparatus for concrete or the like provided with a temperature adjusting means for maintaining the inside of a wall at a constant temperature is disclosed.

  Patent Document 4 describes a sample adiabatic temperature rise test apparatus with self-heating that measures the amount of self-heating of a sample and the rate of heat generation in a test environment in which the temperature of the sample container follows the temperature rise inside the sample. There is disclosed an adiabatic temperature rise test apparatus including an adiabatic temperature rise test container in which a heat medium jacket is integrally formed on an end pressure sample container to which a pressure apparatus is connected.

  Patent Document 5 includes a sample container having a detachable lid, provided with a space for detachably storing a concrete sample, and integrally provided with a heater for heating the outer surface of the container including the lid, and the sample container. In addition, a vacuum container that holds the space containing the sample container in a vacuum state under reduced pressure, a decompression device that decompresses the vacuum container to a predetermined vacuum degree, and measures the center temperature and the ambient temperature of the concrete sample in the sample container There is disclosed a concrete adiabatic temperature rise test device including a temperature control device that adjusts power supplied to a heater based on a measured temperature.

  In Patent Document 6, a main body portion having an outer shape adapted to the shape of a test body, a hollow inside, and an exhaust port capable of evacuating the hollow portion is provided, and a main body is embedded along the outer surface of the main body portion. An adiabatic retention capacity verification apparatus for an adiabatic temperature rise test apparatus comprising a heater that raises the temperature of the surface of the part by imitating the heat generation state due to the hydration reaction of concrete is disclosed.

  As a technique for obtaining a specimen that receives a temperature history substantially the same as that of an actual structure without using a large-scale machine, there is one disclosed in Patent Document 7. In this Patent Document 7, a space portion having the same cross-sectional dimension as that of a concrete structure is secured, a bottom plate of a heat insulating material is disposed on the bottom of the space portion, and an outer container of a synthetic resin peripheral wall having an open top surface thereon. Is supported by a stand, and a simple formable container that can be easily broken is arranged in the outer container with as little gap as possible, and a structure is provided in both the simple formwork container and the outside of the outer container in the space. The same concrete is placed, the simple formwork container is capped and sealed, and the space is covered with a heat insulating material. After the curing period, the simple formwork container is taken out and the specimen is taken from the inside. A method for producing a structural concrete specimen that obtains the above is disclosed.

Moreover, as an intensity | strength management test apparatus of high strength concrete and high fluidity concrete, there exist some which were disclosed by patent documents 8-10, for example.
In Patent Document 8, a concrete specimen after kneading is placed in an internal space sealed with a heat insulating material wall such as polystyrene foam, and the time-dependent change in heat of hydration generated inside the concrete specimen, thermal characteristics of the concrete specimen, insulation A heat insulation curing method for a concrete specimen is disclosed in which the temperature is changed by the heat transfer characteristics of the material wall and the temperature outside the heat insulation wall.

  In Patent Document 9, the same concrete as the concrete structure whose strength is to be estimated is placed in a cylindrical container-like formwork, and the upper opening is closed with a lid, and a specimen is molded. Immediately after installation, the entire outer surface of the mold and lid is divided into a plurality of pieces in the circumferential direction and covered with a heat-insulating coating material with a uniform thickness, and the joints between the coating materials are sealed with a sealing material. A concrete structure strength management method is disclosed in which a specimen is taken out from a mold after curing for a predetermined period and its strength is measured.

  In Patent Document 10, a high-strength concrete specimen is placed in a temperature-controllable curing tank, and the specimen is cured at a temperature following the member temperature following curing temperature, that is, under the same conditions as the temperature history inside the full-scale structure. When doing this, set the specimen temperature follow-up curing period of the specimen to a period of at least about 1.4 times the time for the part to reach the maximum temperature, and after that, use a high-strength concrete specimen in the place where it was sealed on-site. A structure strength management method for high-strength concrete is disclosed.

JP 2000-143111 A Japanese Patent Laid-Open No. 2003-184034 Japanese Patent Laid-Open No. 6-18457 JP-A-8-247978 JP 2000-329719 A JP 2002-181750 A JP-A-8-152386 JP-A-6-201548 JP-A-5-87716 JP-A-5-294754

  However, each test device that measures various thermal characteristic values requires individual test equipment, which requires high costs, so obtaining thermal characteristic values by testing at the design and construction planning stages requires special construction. Except for the current situation, it is rarely done.

Therefore, the present invention provides a small concrete test apparatus capable of obtaining various thermal characteristic values easily and inexpensively and a concrete test method using the same in order to calculate a more accurate temperature crack index. The first purpose.
In addition, the present invention performs a strength management test or a strength test with high reproducibility based on a temperature history of a concrete structure acquired in advance or a temperature measured by a temperature measuring body inserted into a concrete structure under construction. Is the second purpose.

  In order to solve the above problems, a first configuration of the present invention is a cooling device using a container made of a vacuum heat insulating container having high heat insulating performance, a heater for heating the inside of the container, and a Peltier element for cooling the inside of the container. And a fan for making the temperature distribution inside the container uniform, a temperature measuring means embedded in a concrete specimen housed in the container, the temperature measuring means, the heater, and a cooling device. A concrete test apparatus comprising a programmable temperature controller for temperature control.

  The second configuration of the present invention is a concrete test apparatus characterized in that a plurality of concrete specimens can be stored inside the container of the first configuration.

  According to a third configuration of the present invention, a plurality of test apparatus units each including a container, a heater, a cooling device, a fan, and a temperature measuring unit of the first configuration are connected in parallel to the temperature controller. This is a concrete test apparatus.

  The fourth configuration of the present invention is a heat diffusion coefficient using a concrete specimen after performing an adiabatic temperature rise test using the concrete test apparatus of any one of the first to third configurations and performing the adiabatic temperature rise test. It is a concrete test method characterized by conducting a test and a heat capacity test, and performing a test for obtaining a mechanical property value of a specimen subjected to a high temperature history by each test.

  A fifth configuration of the present invention is a concrete test method using the concrete test apparatus according to any one of the first to third configurations, in which the temperature history of a concrete structure acquired in advance or the structure model specimen is obtained. Strength control test of high strength concrete or high fluidity concrete by programming temperature history in the temperature controller and controlling the temperature of the concrete specimen in the vacuum insulation container by the temperature controller so as to reproduce it It is a concrete test method characterized by performing.

  A sixth configuration of the present invention is a concrete test method using the concrete test apparatus according to any one of the first to third configurations, and includes a temperature measuring body connected to a temperature controller in a concrete structure under construction. Inserted and measured temperature is set as a target value, and the temperature controller controls the temperature of the specimen in the vacuum heat insulating container by the temperature controller, thereby conducting a strength management test of high strength and high fluidity concrete. This is a test method.

The present invention provides an inexpensive and small concrete testing apparatus that can measure a plurality of thermal characteristic values and perform various strength management tests with a single unit.
Mass concrete temperature cracking suppression tests include adiabatic temperature rise test, thermal diffusion coefficient test and heat capacity test, and tests to determine the mechanical property values of concrete subjected to high temperature history as a series of tests using a common specimen. It can be carried out.
Obtained by tests to determine the final adiabatic temperature rise obtained in the adiabatic temperature rise test, constants related to the rate of temperature rise, thermal conductivity obtained from the thermal diffusion coefficient test and heat capacity test, and mechanical property values of concrete subjected to high temperature history Compressive strength and Young's modulus are all parameters used for the temperature crack control program.

  As a test method, after first conducting an adiabatic temperature rise test, a thermal diffusion coefficient test is performed using the same specimen. The thermal diffusivity test is obtained by analyzing a temperature rising process by the Glover method by placing a specimen kept constant at 20 ° C. in warm water at 50 ° C. Immediately after that, the concrete specimen that has reached 50 ° C. is immersed in water at 20 ° C., and the heat capacity is measured from the temperature lowering process. Furthermore, the concrete specimens for which all tests have been completed can be tested for strength characteristic values as concrete having undergone a high temperature history.

  In the strength management test of high-strength concrete or high-fluidity concrete, the temperature history of the concrete structure acquired in advance is programmed into the temperature controller and temperature control is performed to reproduce it, or the structure under construction is It can be performed by inserting a temperature measuring body connected to the temperature controller and performing temperature control using the measured temperature as a target value.

  In addition, the strength test of high-strength concrete or high-fluidity concrete is performed by programming the temperature history of the structural model specimen obtained in advance in the temperature controller and controlling the temperature so as to reproduce it. It can be performed by making it insulative only for a few days after placement.

  The apparatus for testing various characteristic values of the concrete structure according to the present invention is characterized by using a vacuum heat insulating container with high heat insulating performance as a container, thereby realizing high control accuracy without being subjected to fluctuations in outside air temperature (disturbance). Moreover, since the temperature fluctuation is small, the heating / cooling device can be downsized.

  In addition, a Peltier element is used in the cooling device, which can greatly reduce the size and cost of the entire device.

  Further, unlike a conventional heat insulation temperature rise tester, the concrete test is put in a plurality of strength test molds and cured, and the strength test becomes possible after the heat insulation test.

  As a strength management test, it is a device that can cure up to eight concrete specimens at the same time, but by connecting a vacuum insulation container with a built-in heating / cooling device to the temperature controller, the expansion of the device can be facilitated. Eight or more specimens can be cured.

  The device according to the present invention is characterized in that a heating device, a cooling device, and a fan for making the temperature in the container uniform are built in the vacuum heat insulating container, and thus the size can be reduced.

  Further, by programming the temperature history into the temperature controller and using a programmable temperature controller for performing temperature control, temperature control with high accuracy becomes possible.

The present invention has the following effects.
(1) By using a vacuum heat insulating container having high heat insulating performance for the container, high control accuracy can be realized without being subjected to fluctuations in the outside air temperature (disturbance), and the heating / cooling apparatus can be downsized because the temperature fluctuation is small.
(2) By using a Peltier element for the cooling device, the entire device can be significantly reduced in size and cost.
(3) Unlike a conventional adiabatic temperature rise tester, a concrete test is placed in a plurality of strength test molds and cured, thereby enabling a strength test after the adiabatic temperature rise test.
(4) As a strength management test, for example, it is a device that can simultaneously cure up to 8 concrete specimens, but a plurality of vacuum insulation containers (test device units) with built-in heating / cooling devices are connected to the temperature controller. By doing so, the expansion of the apparatus can be facilitated, and curing of eight or more concrete specimens becomes possible, and an efficient and economical test can be performed.
(5) Miniaturization can be achieved by incorporating a heating device, a cooling device, and a fan for making the temperature inside the container uniform in the vacuum heat insulating container.
(6) By programming a temperature history in the temperature controller and using a programmable temperature controller for temperature control, a highly reproducible test can be performed.
(7) The contractor can independently conduct a confirmation test of the thermal property value of the concrete used for the structure and check the temperature cracks.
(8) When the ready-mixed concrete supplier supplying the concrete uses the equipment and conducts the test of slump, strength confirmation, etc. instructed by the orderer, the measurement test of various thermal characteristics values is also carried out as a series of tests. Can perform quality control and quality assurance of shipped concrete.
(9) When many tests are carried out using the apparatus of the present invention, data of various thermal characteristic values are accumulated, and relational expressions for various concrete are obtained, this is reflected in the temperature crack analysis program. This can contribute to the improvement of crack index calculation accuracy.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
FIG. 1 is a sectional view showing a configuration of an adiabatic temperature rise test apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view showing an arrangement example of specimens in the apparatus. 1 and 2, the adiabatic temperature rise test apparatus A according to the present embodiment includes two large vacuum insulated containers (φ33 × 36 cm) 1-1 and 1-2 with high thermal insulation performance, which are stacked in two stages. The resin ring 2 to which a rubber packing is attached is arranged between the vacuum heat insulating containers 1-1 and 1-2 to prevent the inflow and outflow of air. Inside the container 1, a specimen 10 of φ10 × 20 cm (with fresh concrete put in a simple mold and compacted with a lid) 3 is placed on an aluminum base 4 in 4 × 2 steps 8 It is possible to store up to pieces. A heater 6 and a heat-resistant fan 7 are installed on the bottom of the container 1 via a base 5, and a heat-resistant fan 8 is provided on the top to make the temperature distribution in the container 1 uniform. It has been. The container 1 is provided with a Peltier element built-in fan 16 for cooling the inside of the container 1.

  A thermocouple (for example, Pt100) 10 is embedded in at least one of the specimens 3 as a temperature measuring body, and highly accurate temperature measurement is performed using the center temperature of the specimen 2. A thermocouple 11 is also used for high-precision temperature control of the heater 6. Outside the container 1 are two temperature regulators 12 and 13 for controlling the temperature in the container 1, an SSR (solid state relay) 14 for controlling the Peltier element built-in fan 16, and for controlling the heater 6. SSR15 is installed. Any one of the temperature controllers 12 and 13 is programmable.

  In this embodiment, since the container 1 is a vacuum heat insulating container having high heat insulating performance (for example, shuttle drum (JIK-W18, inner volume is 18 L)), it is less susceptible to disturbance (outside temperature). Stable temperature control becomes possible. Also, the heating / cooling device can be miniaturized.

  In addition, a maximum of eight specimens 3 can be set in the container 1, and a test (described later) of a thermal diffusion coefficient, a heat capacity, and a strength characteristic value can be performed after the test is completed. Furthermore, the cost can be reduced by using two temperature controllers 12 and 13 and linking them together. The two temperature controllers 12 and 13 are also used for a thermal diffusion coefficient and heat capacity test.

  FIG. 3 is a diagram showing the configuration of the thermal diffusion coefficient test apparatus B according to the embodiment of the present invention, using one vacuum heat insulating container 1-1 of the container 1 used in the adiabatic temperature rise test apparatus A, The specimen 3 in which the thermocouple 10 is embedded is placed therein, and the heat diffusion coefficient of the specimen 3 is measured by the thermocouple 10 while keeping water as a heating medium constant (50 ° C.). In order to control the water temperature in the vacuum heat insulating container 1-1, the temperature controller 12 is used. The heating of the water temperature is performed by a gantry 21 that is placed on the opening of the vacuum heat insulating container 1-1, a specimen base 22 that supports the specimen 3 in a predetermined position, a motor 23, a gear head 24, a rotating shaft 25, a sheath heater 26, an agitation. A structure in which the blades 27 and 28 are integrated is used. The stirring blade 28 is fixed to the rotary shaft 25 and is driven to rotate in the same manner as the stirring blade 27.

The features of the thermal diffusion coefficient test apparatus B are as follows.
By making the agitation motor 23, the sheath heater 26, and the like an integral structure and making them attachable, the vacuum insulation container 1-1 used in the adiabatic temperature rise test can be used.

  Since the thermal diffusion coefficient test can be performed using the temperature controller 12 and one vacuum heat insulating container 1-1 in the temperature controller, the temperature controller 13 and another vacuum heat insulating container 1-2 are used. A heat capacity test (described later) can be performed simultaneously.

  FIG. 4 is a diagram showing a configuration of the heat capacity test apparatus C according to the embodiment of the present invention, and uses one vacuum heat insulating container 1-2 of the container 1 used in the heat insulation temperature rise test apparatus A, A polystyrene foam container is put into the container, and a predetermined amount of water at 20 ° C. is put therein. And the test body 3 which embedded the thermocouple 10 in water is put, and a heat capacity test is performed.

  A high heat insulating property is secured by attaching a heat insulating container 31 made of a heat insulating material such as polystyrene foam inside the vacuum heat insulating container 1-2. A fan 33 incorporating a Peltier element 32 is attached to the bottom of the heat insulating container 31 to control the temperature of water as a heat medium inside the heat insulating container 31 (800 cc of water is kept constant at 20 ° C.). For controlling the water temperature, one of the temperature controllers 12 and 13 used in the adiabatic temperature rise test can be used.

  In this heat capacity test apparatus C, high heat insulation can be secured by using the vacuum heat insulation container 1-2 used in the heat insulation temperature rise test as a container and attaching a heat insulation container 31 such as polystyrene foam inside. Further, the Peltier element built-in fan 16 used in the adiabatic temperature rise test can be diverted as a cooling device.

  Next, a concrete test method using the adiabatic temperature rise test apparatus A, the thermal diffusion coefficient test apparatus B, and the heat capacity test apparatus C configured as described above will be described. FIG. 5 shows the flow of the concrete test method. After the heat capacity test, various mechanical property tests can be performed.

1. Adiabatic temperature rise test First, the same batch of concrete was poured into a can of a summit mold (trade name), and the required number of specimens 3 of φ10 × 20 cm were prepared. At this time, it arrange | positions so that the front-end | tip of the thermocouple 10 may be located in two center part among the three specimens 3 (refer Fig.5 (a)). The concrete composition is a composition using a maximum aggregate size of 20 mm, a kneading temperature of 20 ° C., and an admixture of a high-performance AE water reducing agent, a slag mixing ratio of 40%, and a slag specific surface area of 4000 cm ² / g.
Using this specimen 3, an adiabatic temperature rise test was performed using a commercially available adiabatic temperature rise tester (manufactured by Marui, TBC-1000) and a small adiabatic temperature rise test apparatus A according to the embodiment of the present invention. The size of the commercially available adiabatic temperature rise tester is 146 × 61 × 83.5 cm and is large and occupies a large installation space, whereas the adiabatic temperature rise test apparatus of the present embodiment has a container 1 of φ33 X 76 cm, temperature control device (temperature regulator 12, 13) is 31 x 28 x 18 cm, and a small installation space is sufficient.

The specimen 3 was housed in the container 1 of the adiabatic temperature rise test apparatus A, and the adiabatic temperature rise was measured for 94 hours (about 4 days) with the thermocouple 10 (see FIG. 5B).
Table 1 shows the results of the adiabatic temperature rise test.

Here, Q _∞ is the ultimate adiabatic temperature rise obtained by the least square method, and γ is a constant related to the temperature rise rate. From the results in Table 1, it can be seen that the temperature histories of a commercially available adiabatic temperature rise tester and the adiabatic temperature rise tester of the present invention are substantially the same. The amount of temperature rise at the time of the fourth day is 40.5 ° C. and 40.3 ° C. in the case of the test apparatus of the present invention, and 41.5 ° C. in the adiabatic temperature rise tester. The difference was about 1 ° C. Further, FIG. 6 shows an actual measurement value obtained by each apparatus and an approximate expression based on Q = Q _∞ (1-e ^−γt ).

2. Calculation method of thermal conductivity After conducting an adiabatic temperature rise test, a thermal diffusion coefficient test is performed using the same specimen. The thermal diffusion coefficient test is performed using the thermal diffusion coefficient test apparatus B shown in FIG. First, a specimen (see FIG. 5 (c)) that was kept constant at 20 ° C. using the heat capacity test device C shown in FIG. 4 was placed in 50 ° C. warm water controlled by the thermal diffusion coefficient test device B, and The temperature process was determined by analysis using the Glover method (see FIG. 5D). FIG. 7 shows the test result of the thermal diffusion coefficient h ² obtained by the analysis.

In FIG. 7, the temperature change Θ ′ = (Θ ₁ −Θ _t ) / (Θ ₁ −Θ ₀ ). Here, Θ ₁ is the water temperature, Θ ₀ is the initial age of the specimen, and Θ _t is the temperature of the specimen at time t.
From the temperature drop process result of FIG. 7, the thermal diffusion coefficient is obtained by the Glover method.
Specimen 1 h ² ₁ = 0.00317 (m ² / h)
Specimen 2 h ² ₂ = 0.00313 (m ² / h)

Next, immediately after that, the specimen having reached 50 ° C. is immersed in 20 ° C. water of the heat capacity test apparatus C, and the heat capacity is measured from the temperature lowering process (see FIG. 5 (e)). The test results are shown in FIG.
The heat capacity ρc is obtained from the thermal diffusion coefficient h ² obtained by the Glover method and the temperature change in the temperature drop process of FIG.

Specimen 1 ρc ₁ = 486.2 (kcal / m ³ / ° C.) [2035 (kJ / m / h / ° C.)]
Specimen 2 ρc ₂ = 490.0 (kcal / m ³ / ° C.) [2051 (kJ / m / h / ° C.)]
The thermal conductivity (λ) is λ = ρc × h ² ,
Specimen 1 λ ₁ = 1.54 (kcal / m / h / ° C.) [6446 (J / m / h / ° C.)]
Specimen 2 λ ₂ = 1.53 (kcal / m / h / ° C.) [6404 (J / m / h / ° C.)]

  After all the tests are completed, the specimen 3 can be tested for strength characteristic values as concrete that has undergone a high temperature history (see FIG. 5 (f)).

  As a test for strength management, it can be used as a strength test for high-strength concrete or high-fluidity concrete. FIG. 9 is an explanatory view showing a method of performing heat insulation curing in the strength management test, and has the same configuration as FIG.

  In the test for strength management, as shown in FIG. 10, the temperature history of the concrete structure acquired in advance is programmed in the temperature controller 12, and temperature control is performed so as to reproduce it, or as shown in FIG. As described above, the temperature control body connected to the temperature controller 12 is inserted into the concrete structure under construction, and the temperature control is performed with the measured temperature as a target value, so that the strength management test of high-strength concrete or high-fluidity concrete is performed. It can be carried out.

  For example, as shown in FIG. 12, the strength test of high-strength concrete is performed by programming the temperature history of the mass specimen obtained in advance in the temperature controller 12 and controlling the temperature so as to reproduce it, or by using an apparatus. After placing concrete in the building, heat insulation is performed only for a few days.

  The present invention is an inexpensive and small concrete test apparatus capable of measuring a plurality of thermal characteristic values and various strength management tests with one unit, and a concrete test method using the same, as a measure for suppressing temperature cracks in concrete structures and the quality of concrete. It can be suitably used for management.

It is sectional drawing which shows the structure of the adiabatic temperature rise test apparatus which concerns on embodiment of this invention. It is a top view which shows the example of arrangement | positioning of the test body in the adiabatic temperature rise test apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the thermal-diffusion-coefficient test apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the heat capacity test apparatus which concerns on embodiment of this invention. It is explanatory drawing which shows the flow of the concrete test method which concerns on embodiment of this invention. It is a graph which shows the constant regarding the ultimate heat insulation temperature rise amount and a temperature rise rate. It is a graph which shows the test result of the thermal diffusion coefficient calculated | required by analysis. It is a graph which shows a heat capacity test result. It is explanatory drawing which shows the method of performing heat insulation curing by the test for intensity | strength management. It is explanatory drawing which shows the method of programming the temperature history of a structure to a temperature controller, and performing the quality control test of high strength or high fluidity concrete. It is explanatory drawing which shows the method of reproducing the temperature history of the structure under construction and performing the quality control test of high strength or high fluidity concrete. It is explanatory drawing which shows the structure of the apparatus which performs the intensity | strength test of concrete.

Explanation of symbols

A heat insulation temperature rise test device B heat diffusion coefficient test device C heat capacity test device 1 container 1-1, 1-2 vacuum heat insulation container 2 ring 3 specimen 4, 5 units 6 heater 7 heat resistant fan 8 heat resistant fan 10, 11 thermocouple (Temperature sensor)
12, 13 Temperature controller 14, 15 SSR
16 Peltier element built-in fan 21 Base 22 Specimen base 23 Motor 24 Gear head 25 Rotating shaft 26 Sheath heater 27, 28 Stirring blade 31 Thermal insulation container 32 Peltier element 33 Fan

Claims (6)

A container comprising a vacuum insulation container with high heat insulation performance;
A heater for heating the inside of the container;
A cooling device using a Peltier element for cooling the inside of the container;
A fan for making the temperature distribution inside the container uniform;
Temperature measuring means embedded in the concrete specimen stored in the container,
A concrete testing apparatus comprising: a programmable temperature controller connected to the temperature measuring means, the heater, and the cooling device for performing temperature control.   The concrete test apparatus according to claim 1, wherein the container is capable of storing a plurality of the concrete specimens therein.   The test apparatus unit comprising the container, the heater, the cooling device, the fan, and the temperature measuring unit is connected in parallel to the temperature controller, according to claim 1 or 2. The concrete test equipment described. Conduct a heat insulation temperature rise test with the concrete test apparatus according to any one of claims 1 to 3,
Conducting a thermal diffusion coefficient test and a heat capacity test using the concrete specimen after performing the adiabatic temperature rise test,
A concrete test method characterized in that a test for obtaining a mechanical characteristic value of a concrete specimen subjected to a high temperature history by each of the tests is performed.   A concrete test method using the concrete testing apparatus according to any one of claims 1 to 3, wherein a temperature history of a concrete structure or a structure model specimen obtained in advance is used as the temperature controller. The strength control test of high-strength concrete or high-fluidity concrete is performed by controlling the temperature of the concrete specimen in the vacuum heat insulation container by the temperature controller so as to reproduce it. Concrete test method.   A concrete testing method using the concrete testing apparatus according to any one of claims 1 to 3, wherein a temperature measuring body connected to the temperature controller is inserted into a concrete structure under construction, and the measured temperature. A concrete test method characterized in that a strength control test of high-strength concrete or high-fluidity concrete is performed by controlling the temperature of the concrete specimen in the vacuum heat insulating container by the temperature controller with the temperature controller as a target value.

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