JP2995459B2 - Cement kneaded material sensor and cement kneaded material casting condition inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION In the construction of a structure using a cement kneaded material such as concrete, mortar, paste or the like, after the cement kneaded material is cast into a mold, vibrations are given by a vibrator or the like to form the structure. Are compacted so that no unfilled portions such as gaps are generated in the horn. However, since the filled portion in the mold cannot be visually observed, an unfilled portion may remain. The present invention finds such an unfilled portion during casting, inspects the filled state of the cast cement kneaded material in order to compact again with a vibrator or the like, and at the same time, generates by the hydration reaction of concrete. The present invention relates to a cement kneaded material sensor and a cement kneaded material placing condition inspection device for performing a temperature inspection for temperature control so as to prevent cracks or the like from occurring.

[0002]

2. Description of the Related Art Conventionally, at a construction site, for example, an unfilled portion of cast fresh concrete (mixed cement, water, sand and gravel at an appropriate ratio and having a property of hardening by a hydration reaction). In order to confirm whether or not there is in the formwork, the worker hit with a mallet or the like from the outside of the formwork, and the sound of the blow determined whether or not there was an unfilled portion. In other words, this method is based on the fact that the level of the impact sound depends on the frequency of the propagating wave when air is accumulated in the unfilled portion where fresh concrete is not filled. When it is determined that the unfilled portion exists in the mold, the portion is vibrated by a vibrator or the like to compact the portion.

[0003]

In the conventional inspection described above, the accuracy is different depending on the skill of the worker since no visual inspection and confirmation can be made from the outside. There was a problem that it was easy to come out.
If the concrete is hardened while overlooking the existence of the unfilled portion of the fresh concrete, the structure is not satisfied in terms of strength, the service life is shortened, or an accident is caused.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a cement kneaded material sensor and a cement kneaded material placing condition inspection device which solve the problems.

Another object of the present invention is to provide a sensor of a cement kneaded material which does not adversely affect the strength of the cement kneaded material by reducing the sensor remaining in the cement kneaded material and reducing the number of lead wires. And

Another object of the present invention is to control the temperature of each part of fresh concrete. This temperature control is performed because fresh concrete has a property of generating heat due to a hydration reaction during hardening, and if there is a temperature difference between the inside and the surface layer, cracks may occur. When the temperature difference is large, the surface layer is heated with a stove or the like, or a pipe is put inside, water is passed through, and cooling is performed in order to average the temperature gradient.

Still further, the present invention provides a cement kneaded material capable of accurately determining whether or not a cement kneaded material exists at each sensor arrangement site in accordance with the temperature of the kneaded material after casting. It is an object of the present invention to provide a driving state inspection device.

[0008]

According to the present invention, there is provided a sensor for a cement kneaded material, which comprises one electrode and a pair of thermocouples. And a resistance detecting unit for detecting an electric resistance value by one of the electrode and the thermocouple.

Further, the apparatus for inspecting the state of cement-kneaded material of the present invention comprises a temperature detector for detecting as an electric signal the temperature inside the cement-kneaded material cast on a mold, and a resistance for detecting an electric resistance value. While a plurality of sensors provided with a value detection unit are arranged inside the mold, the temperature detection unit and the resistance value detection unit of each of the sensors are individually electrically connected to each other, and according to the electric signal detected by each sensor. While measuring the temperature, whether or not the cement kneaded material is present at each sensor placement site by the electric resistance value detected by each sensor is determined by a set value corresponding to the measured temperature, outside the formwork. It has a measuring device arranged.

Furthermore, the apparatus for inspecting the state of cement-kneaded material of the present invention comprises, secondly, a pair of thermocouples and one electrode, which detects the temperature inside the cement-kneaded material cast by the thermocouple. And a plurality of sensors constituting a resistance value detecting section for detecting an electric resistance value by one of the thermocouples and the electrode, and a thermocouple constituting the temperature detecting section via a switch. Connect, measure the temperature of the sensor placement site by measuring the voltage value generated by the thermocouple, and output the temperature signal,
The resistance value detection unit is connected to a bridge circuit connected to a power supply via a switch, and an unbalanced voltage measured by applying a current between one of the electrodes and the thermocouple, and an unfilled cement kneaded material that has been input in advance. Of the set values for each temperature of the reference unbalanced voltage serving as a reference for determining the presence or absence of the portion, by comparing the set value at the measured temperature, it is determined whether the cement kneaded material is present at each sensor arrangement site. A measurement unit that determines and outputs the determination signal, a switch controller that can arbitrarily switch the switches, and a determination signal and a temperature signal that are output from the measurement unit, while the measurement unit and the switch controller A measurement control unit to be controlled, and a judgment signal and a temperature signal are input from the measurement control unit, and a set value of the reference unbalanced voltage is controlled via the measurement control unit. That a main control unit, in tandem to the main control unit, is provided with a display unit for displaying the determination of the presence or absence of the temperature and the cement kneaded product of the sensor installation site.

[0011]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Here, FIGS. 1 to 6 of the accompanying drawings show the present embodiment, and FIG. 1 is a front view of a sensor fixed to a mold, FIG.
3 is a plan view of the sensor, FIG. 3 is a side view of the sensor, FIG. 4 is a block diagram showing an entire circuit of the inspection device, FIG. 5 is a block diagram showing a circuit of the data logger, and FIG. 6 is a circuit diagram of a switch box. .

As shown in FIGS. 1 to 3, the sensor 1 includes a pair of thermocouples 3 connected to a pair of lead wires 2a and 2b and one electrode 4 connected to a lead wire 4a. To be fixed. The thermocouple 3 is made of a pair of copper 3a and constantan 3b and their ends are in contact with each other. The thermocouple 3 constitutes a temperature detecting section for detecting the internal temperature of the poured fresh concrete, and the other paired with the electrode 4. One of these thermocouples 3a and the electrode 4 constitutes a resistance value detecting section for detecting an electric resistance value. The pedestal 5 is formed so as to fit into a through hole 6 provided in a mold a into which fresh concrete is driven, and is provided with hooks 7 on both sides.

As shown in FIG. 4 and FIG.
Has a plurality of the above-mentioned sensors 1... Which are arranged inside fresh concrete driven into a formwork a (see FIG. 1) and detect the electric resistance value and also detect the internal temperature of the fresh concrete. In addition, the inspection device 8 includes a switch box 9 disposed outside the fresh concrete and electrically connected to the resistance value detection units 3a and 4 and the temperature detection unit 3 of the sensors 1. Each of the sensors 1... Is connected to the switch box 9 to determine whether or not fresh concrete exists at each sensor 1. A measurement unit 10 for measuring the temperature of the part, a bridge power supply 11, a data logger 13 including a measurement control unit 12, a main control unit for storing and analyzing an output signal from the data logger 13 and outputting a control signal 14 and each sensor 1.
A CRT 15 for displaying the determination and the temperature of the placement site, and a printer 16 for printing out the determination and the temperature at each sensor 1...
And a measuring device 17 composed of

Next, a circuit configuration relating to the function of measuring the temperature inside the fresh concrete of the inspection device 8 and determining the presence or absence of the fresh concrete will be described. FIG. 4-
As clearly shown in FIG. 6, the leads 2a and 2b of the thermocouple 3 of the sensor 1 are connected to the switches (S
Through W1) and (SW2), it is connected to the measurement unit 10.
Also, a lead wire 2a of one of the thermocouples 3a of the sensor 1 and a lead wire 4a of an electrode 4 constituting a resistance value detecting unit.
Are the bridge circuit 18 and the switches (SW3), (SW
After 4), it is connected to the measuring unit 10. Further, a DC bridge power supply 11 is connected to the bridge circuit 18 via switches (SW5) and (SW6).

In the switch box 9, the switches (SW1), (SW2), (SW3), (SW4),
(SW5), (SW6)... And the bridge circuit 18.
.. and switches (SW1), (SW1)
2), (SW3), (SW4), (SW5), (SW
6) Switch controller 19 for sequentially switching...
Is provided.

When the switches (SW1) and (SW2) are turned on, the switches (SW3), (SW4), (SW5),
When (SW6) is off, the minute voltage generated by the thermocouple 3 is output to the measuring unit 10. When the minute voltage is input, the measurement unit 10 calculates the temperature of the sensor 1 from the value, and outputs the temperature signal to the measurement control unit 1.
Output to 2.

The switches (SW1), (SW1)
2) is off and the switches (SW3), (SW4), (S
When the DC voltage of the bridge power supply 11 is applied to the bridge circuit 18 connecting one electrode 3a of the thermocouple 3 and the electrode 4 via the lead wires 2a and 4a in a state where W5) and (SW6) are turned on, the thermocouple 3 is turned off. On the other hand, since current flows between the electrode 3a and the electrode 4, an unbalanced voltage is generated in the bridge circuit 18 and is output to the measuring unit 10. This unbalanced voltage changes depending on the resistance between one of the thermocouples 3a and the electrode 2 and, for example, when the resistance is small (when fresh concrete is present on the one 3a between the thermocouple 3 and the electrode 4). ), And low when the resistance value is large (when water or air exists between the thermocouple 3 on one side 3a and the electrode 4).
The reason why fresh concrete has higher conductivity than water (small electric resistance) is that cement contained in fresh concrete dissolves in water and is ionized. The conductivity varies depending on the temperature, the type of cement kneaded material (concrete, mortar, paste), or the mixing ratio of the same kind of cement kneaded material such as sand, water, and gravel.

When the unbalanced voltage is input to the measuring unit 10, the value is set to a set boundary value (hereinafter referred to as a set value).
If it is above, it is determined that fresh concrete is present in the portion of the sensor 1, and if it is below the set value, on the contrary, a cavity is formed in the portion of the sensor 1 and air or water is present and unfilled. It is determined that the portion exists, and the determination signal is output to the measurement control unit 12.

In determining the set value, a reference cement kneaded material whose temperature, type, and mixing ratio are known in advance is placed between one of the electrode and the thermocouple in the same reference bridge circuit as the bridge circuit 11. And determined based on the unbalanced voltage obtained by energizing. Then, the data of the set values determined separately for each temperature, each type, and each mixing ratio are input from the control unit to the measurement unit 10.
The measurement unit 10 performs the determination using the set value of the temperature corresponding to the actually measured temperature among the set values.

As described above, the switches (SW1), (SW1)
2) and switches (SW3), (SW4), (SW5),
By alternately switching ON / OFF of (SW6), the measuring unit 10 measures the temperature of the sensor 1 and determines whether or not there is fresh concrete at the sensor 1 based on a set value corresponding to the measured temperature. It is determined whether or not there is an unfilled portion), and the same operation is sequentially performed for each of the following sensors 1. The measurement control unit 12 linked to the measurement unit 10 has a function of inputting the determination signal and the temperature signal from the measurement unit 10 and temporarily storing the same, a function of instructing an operation of the switch controller 19 of the switch box 9, It has a function of instructing the measurement unit 10 to change the set value by inputting the operation of the main control unit 14.

As clearly shown in FIG.
Are the inputs from the main control unit 14, and the respective sensors 1.
The presence or absence of the unfilled portion and the temperature of the portion are displayed, and the printer 7 prints the determination and the temperature.

Next, another embodiment of the sensor will be described with reference to FIGS. Here, FIG. 7 is a front view of the sensor, and FIG. 8 is a side view of the same. The sensor 100 according to this embodiment is configured so as to be able to be fixed to a reinforcing bar, and an electrode, a thermocouple and a lead wire are connected to the sensor 1 described above.
Therefore, descriptions of these electrodes, thermocouples, and lead wires are omitted, and only the same reference numerals as those given to the respective members of the sensor 1 are used for the corresponding members.

As clearly shown in FIGS. 7 and 8, a sensor 100 according to the present embodiment has a pedestal 101 as a feature. That is, the pedestal 101 is provided with four through holes 103... So as to be fixed to the reinforcing bar b incorporated in the concrete with the wire 102, and is passed through the through holes 103. Wire 102 to rebar b
It is wound around.

Next, an example of use of the inspection apparatus 8 using the sensor 1 and the sensor 100 according to the above embodiment will be described. As shown in FIG. 9, first, a mold a
Are provided, and the sensors 1-1 to 1-6 are arranged and fixed inside the upper surface of the mold a.
From 00-1 to 100-12 are arranged and fixed, and fresh concrete is poured as shown by the arrow. In the measurement control unit 12 connected to the lead wires 2a, 2b, 4a,.
The above-mentioned set value data for determining whether or not fresh concrete exists in the portion of the sensor 1 is input to the measurement control unit 12 of the data logger 13, and the inspection device 8 is operated. Let it. The set value data corresponds to the mixing ratio of cement, water, sand, and gravel of the poured fresh concrete, and has a value for each temperature.

Subsequently, the switches (SW1), (SW2), (SW3), (SW4),
Of (SW5) and (SW6), switches (SW1),
When (SW2) is turned on by the switch controller 19, the minute voltage generated by the thermocouple 3 is output to the measurement unit 10, the temperature is calculated, and the temperature signal is input to the measurement control unit 12 and stored. At this time, the measuring unit 10
A set value corresponding to the measured temperature is selected from the set value data. Further, the switch controller 1
9, switch (SW) corresponding to sensor 1-1
1), (SW2), (SW3), (SW4), (SW
5) and (SW6), switches (SW3) and (SW6)
4) When (SW5) and (SW6) are turned on by the switch controller 19, the current flows between the electrode 4 and one of the thermocouples 3a, and the bridge circuit 18 applied to the bridge power supply 18 and in an equilibrium state is not operated. An equilibrium state is established, and the unbalanced voltage is output to the measurement unit 10. When the unbalanced voltage is higher than the set value, fresh concrete exists between the electrode 4 and one of the thermocouples 3a,
It is determined that there is no unfilled portion, and the determination signal is input to the microcomputer 12 and temporarily stored. Subsequently, the switch (SW) is controlled by the switch controller 19.
3), (SW4), (SW5), and (SW6) are turned off, and the switches (SW3), (SW) of the next sensor 1-2 are turned off.
4), (SW5) and (SW6) are turned on, and the same operation as that of the sensor 1-1 is performed.
2 and stored. Hereinafter, the sensor 1-3 to the sensor 1
The determination signal is similarly input to and stored in the measurement control unit 12 through -6 to 100-1.

Subsequently, the sensors 100-2 to 100-12
, Corresponding switches (SW1), (SW2),
Of the switches (SW3), (SW4), (SW5), and (SW6), the switches (SW1) and (SW2) are sequentially turned on and off by the switch controller 19, the temperature is calculated, and the temperature signals are measured. Control unit 1
2 and stored.

As described above, each determination signal and temperature signal are temporarily stored in the measurement control unit 17, and are stored in the main control unit 14 by operating the main control unit 14. Further, by operating the main control unit 14, the respective judgments and the temperatures are displayed on the CRT 15 or printed by the printer 16.

The concrete structure to be constructed as described above has a large width and thickness, a reinforcing bar is disposed inside, and a vertical thickness of a portion for inputting fresh concrete is thinner than a deep portion. Since the unfilled portion of the fresh concrete is apt to be formed on the upper side of the inner part, only the filling state of the upper mold a is determined from the sensor 1-1 to the sensor 1.
While the above determination is made up to sensor 100-1 through -6,
In order to prevent a crack due to a temperature difference between the central part and the vicinity of the outside due to heat generated during hardening of the concrete, a switch is provided to measure the internal temperature from the sensor 100-2 to the sensor 100-12 on the internal rebar. The main controller 15 is operated so as to control the switching of the controller 19. When the mold a is removed after the hardening of the fresh concrete, the sensors 1-1 to 1-6 are removed together with the mold a, and the sensors 100-1 to 100-6 are removed.
0-12 are the lead wires 2a, 3a, 3b,.
At the outer surface of the concrete. Therefore, these sensors 100-1 to 100-12 remain in the concrete together with some of the lead wires 2a, 3a, 3b.

The present invention is not limited to the above embodiment. For example, the method of measuring the electric resistance of the electrode portion does not need to use the bridge circuit 18. Further, the display unit may be replaced with another unit such as an LED instead of the CRT.

[0030]

As described above, according to the present invention, the present invention as defined in claim 1 inspects the presence or absence of an unfilled portion in the cement kneaded material,
In a sensor that can perform temperature inspection at the same time, a thermocouple is used as the other electrode, so that the number of electrodes can be reduced to one, and the sensor can be formed small, and three leads can be used. This also has the effect of less adversely affecting the strength of the structure.

Further, according to the present invention, it is possible to determine whether or not an unfilled portion exists in the cement kneaded material, and at the same time, to control the temperature inside the cement kneaded material and to measure the temperature. Is performed on the basis of the set value corresponding to, so that the effect that the determination result is accurate is exhibited.

Further, the present invention described in claim 3 provides:
In addition to the effects of the invention described in claim 2,
While switching the switch with the switch controller, input the unbalanced voltage from the bridge circuit and the minute voltage from the thermocouple separately to determine whether the cement kneaded material exists at each sensor placement site, and determine the temperature. Is calculated by the measurement unit, so that the circuit can be simplified and the set value of the unbalanced voltage serving as a reference for determining the presence or absence of an unfilled portion of fresh concrete can be controlled. Therefore, the set value can be changed according to the type of the cement kneaded material and the surrounding environment of the structure, and further, there is an effect that the determination result and the temperature can be displayed or printed.

[Brief description of the drawings]

FIG. 1 is a front view of a sensor fixed to a mold.

FIG. 2 is a plan view of a sensor.

FIG. 3 is a side view of the sensor.

FIG. 4 is a block diagram showing a circuit of the inspection device.

FIG. 5 is a block diagram showing a data lock circuit.

FIG. 6 is a circuit diagram of a switch box.

FIG. 7 is a front view of a sensor according to another embodiment.

FIG. 8 is a side view of the same.

FIG. 9 is a longitudinal sectional view showing a state where a sensor is arranged in a formwork and fresh concrete is poured.

[Explanation of symbols]

a Fresh concrete b Reinforcing bar 1,1-1-1-6,100,100-1-100-1
2 Sensor 2a, 2b, 4a Lead wire 3 Thermocouple 3a One thermocouple 3b The other thermocouple 4 Electrode 5 Pedestal 8 Inspection device 9 Switch box 10 Measurement unit 11, Bridge power supply 12 Measurement control unit 13 Data logger 14 Main control unit 15 CRT 16 Printer 17 Measuring device 18 Bridge circuit 19 Switch controller

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sakae Ushijima 3-1-14 Toyosumi, Kashiwa-shi, Chiba B204 (72) Inventor Hideaki Taniguchi 1-1-12 Takamihara, Kakizaki-cho, Inashiki-gun, Ibaraki Landscape C105 (58) Surveyed field (Int.Cl. ⁶ , DB name) E04G 21/02 103 G01K 1/14 G01K 7/02

Claims (3)

(57) [Claims] 1. A sensor comprising one electrode and a pair of thermocouples, the sensor comprising a temperature detector for detecting a temperature inside a cement kneaded material cast by the thermocouple, and a sensor for detecting the temperature inside the cement kneaded material. A sensor for a cement kneaded material, wherein a resistance value detecting unit configured to detect an electric resistance value by one of thermocouples is configured. 2. A plurality of sensors provided with a temperature detecting section for detecting, as an electric signal, a temperature inside a cement kneaded material cast on a mold, and a resistance value detecting section for detecting an electric resistance value. On the other hand, the temperature sensor is electrically connected to a temperature detection unit and a resistance value detection unit of each of the sensors, the temperature is measured by the electric signal detected by each sensor, and the electric resistance detected by each sensor is arranged. Whether the cement kneaded material is present at each sensor placement site by the value is determined based on a set value corresponding to the measured temperature, and a casting state inspection of the cement kneaded material having a measuring device arranged outside the formwork. apparatus. 3. A thermocouple comprising a pair of thermocouples and one electrode, constitutes a temperature detecting section for detecting the temperature inside the cement kneaded material cast by the thermocouple, and includes one of the thermocouples and the electrode. A plurality of sensors constituting a resistance value detecting section for detecting an electric resistance value, and a thermocouple constituting the temperature detecting section connected to a thermocouple via a switch, and a voltage value generated by the thermocouple is measured to measure a sensor arrangement portion. And outputs the temperature signal, and connects the resistance value detection unit to a bridge circuit connected to a power supply via a switch, and conducts the current between one of the electrodes and the thermocouple to measure the unbalance. The voltage and the set value at the measured temperature among the set values for each temperature of the reference unbalance voltage serving as a reference for determining the presence or absence of the unfilled portion of the cement kneaded material that has been input in advance are compared. By doing so, a measurement unit that determines whether or not the cement kneaded material is present at each sensor placement site and outputs a determination signal thereof, a switch controller that can arbitrarily switch the switches, and an output from the measurement unit A measurement control unit that controls the measurement unit and the switch controller while inputting a determination signal and a temperature signal, and a determination signal and a temperature signal that are input from the measurement control unit, and the set value of the reference unbalanced voltage is measured. Cement kneading characterized by comprising a main control unit that can be controlled via a control unit, and a display unit that is linked to the main control unit and that displays the temperature of each sensor installation site and the determination of the presence or absence of cement kneaded material. A device for inspecting the driving condition of objects.