JP2012172375A - Concreting management method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concreting management method and apparatus in which quality management of deposited concrete is made possible by grasping concreting situations continuously in real time.SOLUTION: A level sensor 16 having a pair of electrode wires 1602 is disposed at an interval in a circumferential direction inside a mold 10 and while extending in a vertical direction of the mold 10 that is a finish height direction of concrete to be deposited. A change in electrostatic capacitance which is generated in accordance with a specific dielectric constant of concrete between the pair of electrode wires 1602 of the level sensor 16 is measured by a measuring circuit 18. On the basis of this measurement, strength management or quality management of deposited concrete such as concreting speed, the remaining quantity required for concreting into the mold, moisture content, cold joint or the like is made possible.

Description

  The present invention relates to a concrete placement management method and apparatus, and more specifically, continuously detects and confirms a placement situation in a void such as a concrete formwork which is a time-dependent curable liquid material, and places the placement. The present invention relates to a concrete placement management method and apparatus that enables quality control of concrete to be performed.

  As an example of detecting and confirming the filling state of the liquid filling, for example, there is a case where a general liquid such as fuel, oil or water is filled in a container or a tank. Examples of time-dependent curable liquid fillings include, for example, placing concrete, mortar, and cement paste into a formwork during construction work in civil engineering and construction work, or existing structures and steel sheets for reinforcement work. And a filling material such as a liquid epoxy resin in between.

Conventionally, for example, the techniques shown in Patent Documents 1 to 4 are known as a filling detection method for detecting the filling state of concrete into a mold.
The filling detection methods disclosed in these patent documents include a method using a voltage-type sensor element, a method using a camera and visual confirmation, or actually measuring a filling state in a container with a ruler or a scale. There are a system type and a system in which the actual filling amount is grasped and the filling ratio in the container is obtained.

JP 2008-8707 A JP 2004-301616 A JP 2003-202328 A JP 2002-47800 A

  However, in the method of detecting the filling state with a sensor installed in the container as in the detection method shown in Patent Document 1 or the like, only the filling state at the point where the sensor is installed can be obtained, and the filling state is continuously obtained. It is not possible to grasp in real time. In addition, in the case of a time-dependent curable liquid material that does not have self-flatness and has viscosity like concrete and mortar, the form of the time-dependent curable liquid material can be determined even if the filling amount can be grasped. It is difficult to grasp whether it is filled with. In addition, when the filling state and filling shape of the time-dependent curable liquid material are related to the quality of the liquid material, it is also necessary to three-dimensionally grasp the filling state of the time-dependent curable liquid material.

  The present invention has been made in view of the above points, and enables continuous real-time grasping of the concrete placement condition, which is a time-dependent curable liquid material, and enables quality control of the concrete placed. An object of the present invention is to provide a concrete placement management method and apparatus.

  In order to achieve the above-mentioned object, the present invention is a concrete placement management method for placing in a space extending vertically, and is vertically parallel to each other at a certain interval in the horizontal direction. A level sensor formed by covering a pair of extending electrode wires with an insulating material is installed in the space, and the concrete is placed in the space according to the relative dielectric constant of the concrete as the concrete is placed in the space. Calculate the concrete launch height in the void based on the change in capacitance generated between the lines, calculate the concrete placement speed from the launch height change, and It is characterized in that the remaining amount required for placing concrete in the remaining space is calculated from the rising height.

  Further, the present invention is a concrete placement management device placed in a space extending vertically, and is installed in the space, and is vertically parallel to each other at a certain interval in the horizontal direction. A level sensor formed by covering a pair of extending electrode wires with an insulating material, and electrostatic generated between the pair of electrode wires in accordance with a relative dielectric constant of the concrete when concrete is placed in the void. A calculating means for calculating a launch height of the concrete placed in the void based on a change in capacity, and a placement for calculating a concrete placement speed from the change in the launch height It is characterized by comprising speed calculating means and remaining amount calculating means for calculating a remaining amount required for placing concrete into the remaining space from the launch height.

  According to the concrete placement management method and apparatus of the present invention as described above, based on the measured value of the level sensor, the concrete placement speed, the remaining amount required for concrete placement with respect to the volume of the void are continuously obtained. It is possible to grasp and confirm in real time. As a result, it is possible to prevent a concrete placement failure in the empty space.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory layout diagram of an entire apparatus when a concrete placement management method and apparatus according to the present invention are applied to the placement of externally wound concrete on an existing concrete pier. It is a block diagram of the level sensor and measurement circuit which are used for the concrete placement management method and apparatus of this invention. It is a functional block diagram of the personal computer used for the concrete placement management method and apparatus of this invention. It is a graph which shows the relationship between the concrete launch height using the level sensor of this invention, and an electrostatic capacitance. It is a graph which shows the relationship between the concrete launch height using the level sensor of this invention, and measurement time. It is explanatory drawing at the time of carrying out the monitor display by color-coding the casting height of casting concrete and the elapsed time of casting concrete in the concrete placement management method of this invention.

(First embodiment)
Hereinafter, an embodiment in which the concrete placement management method and apparatus according to the present invention is applied to the placement of externally wound concrete on an existing concrete pier will be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, the outer-wrapped concrete 14 cast on the outer periphery of the existing concrete pier 12 having a diameter of 4 m has a cylindrical shape with a height of 3.6 m and a thickness of 200 mm. The concrete driving height is about 50 mm. Moreover, the formwork 10 for placing the outer concrete roll 14 is installed around the outer periphery of the existing concrete pier 12 with an interval of 200 mm.

  In the concrete placement management method and apparatus shown in the present embodiment, at least four level sensors 16 are arranged at regular intervals along the outer periphery of the existing concrete pier 12 inside the mold 10 where the concrete is placed. And arranged vertically. When the level sensor 16 is installed, the level sensor 16 is arranged along a main bar extending vertically (not shown) arranged vertically between the outer periphery of the existing concrete pier 12 and the mold 10. Further, a measuring circuit 18 for measuring a change in capacitance generated according to the relative dielectric constant of the concrete to be placed is connected to the upper end of each level sensor 16.

As shown in FIG. 2, the level sensor 16 is installed in a space 32 formed between the outer periphery of the existing concrete pier 12 and the mold 10 and extending in the vertical direction, and has a constant interval in the horizontal direction. And a pair of electrode wires 1602 extending in the vertical direction in parallel to each other, and an insulating material 1604 covering the pair of electrode wires 1602.
As shown in FIG. 2, the measurement circuit 18 is connected to an input terminal 1802 connected to the upper ends of a pair of electrode lines 1602, a DC power source 1804 that applies a constant DC voltage Vin between the electrode lines 1602, and a pair In accordance with the change in capacitance generated between the pair of electrode wires 1602 in parallel with the relative permittivity of the cast concrete and the height of the cast concrete. The fixed resistor 1806 for extracting the charging voltage Et and an output terminal 1808 connected to both ends of the fixed resistor 1806 are provided.

  The output terminal 1808 of each measurement circuit 18 corresponding to each level sensor 16 is connected to the switching circuit 22 via the cable 20 as shown in FIG. Further, the switching circuit 22 is connected to the personal computer 24. The switching circuit 22 takes out the output voltage Vout that is output to the output terminal 1808 of each measurement circuit 18 and is proportional to the charging voltage Et, and supplies it to the personal computer 24.

  The personal computer 24 performs necessary arithmetic processing on the output voltage Vout taken into the personal computer 24 so that the height of the cast concrete, the casting speed of the concrete, and the remaining amount required for placing the concrete on the formwork 16 are obtained. Executes processes such as determining whether or not a cold joint has occurred, displaying a monitor for the height of the cast concrete, displaying a color-coded monitor for the elapsed time of the cast concrete, and calculating the moisture content of the cast concrete.

  For this purpose, as shown in FIG. 3, the personal computer 24 includes a launch height calculation means 2402 for calculating the launch height of the concrete placed in the empty space, and concrete from the calculated launch height change. A placement speed calculation means 2404 for calculating the placement speed of the concrete, a remaining amount calculation means 2406 for calculating the remaining amount required for placing the concrete in the remaining space from the launch height, Time measurement means 2408 for measuring the time from the concrete placement end time to the start of the next concrete placement every time concrete is placed, and this measurement is performed. Cold joint presence / absence judging means 2410 for judging whether or not a cold joint is generated from time, and placing concrete into the empty space are divided into a plurality of times. The elapsed time measuring means 2412 that measures the elapsed time from the beginning of placing the concrete to be placed and the launch height calculated by the launch height calculating means 2402 are displayed on the monitor and measured by the elapsed time measuring means 2412. The graphic display control means 2414 for displaying the elapsed time for each color as it is placed and displayed on the monitor, and compaction is performed after the concrete placement on the mold 10 is finished, and a pair before and after the compaction. A moisture content calculating means 2416 for obtaining the moisture content of the cast concrete from the change in capacitance generated between the electrode wires 1602 and a monitor display unit 2418 for displaying the results of these means.

Next, the operation of the concrete placement management method and apparatus shown in the present embodiment configured as described above will be described.
Since there are a large number of ions in the concrete placed on the mold 10, that is, fresh concrete (mortar), when concrete is interposed between and around the pair of insulation-coated electrode wires 1602. Then, the capacitor C1 corresponding to the relative dielectric constant of the concrete is used as the electrolyte. The capacitor C1 is connected in parallel along the height h of the cast concrete. As the concrete launch height h increases, the number of capacitors C1 connected in parallel increases and the capacitance increases. Here, a capacitor C2 having a capacitance corresponding to the dielectric constant of air is also formed in parallel between the electrode wires 1602 exposed to the air. Accordingly, the capacitance generated between the pair of electrode lines 1602 is a value obtained by adding the capacitor C1 connected in parallel and the capacitor C2 connected in parallel. This capacitance changes as the concrete rising height h changes.
The capacitance between the electrode wires 1602 using concrete as an electrolyte is about 10 times the capacitance in the case of air.

  Therefore, a constant DC voltage Vin is applied between the input terminal 1802 and both electrode lines 1602, charges are applied to both electrode lines 1602, and the voltage between both electrode lines 1602 is measured by the measurement circuit 18. In this case, in the measurement circuit 18, the relationship of output voltage Vout = Et / (R + 2r) is established. Here, R is the resistance value of the fixed resistor 1806, and r is the specific resistance of the electrode line 1602.

  The measurement result of the output voltage Vout by the measurement circuit 18 is shown in FIG. As is apparent from the results shown in FIG. 4, the output voltage Vout proportional to the capacitance generated between the two electrode wires 1602 in accordance with the relative dielectric constant of the concrete and the rising height h of the concrete are approximately proportional. It becomes a related cubic curve. The output voltage Vout measured by the measurement circuit 18 of each level sensor 16 is sequentially taken into the personal computer 24 through the switching circuit 22.

The launch height calculation means 2402 of the personal computer 24 calculates the launch height h of the concrete placed on the mold 10. The calculation result is displayed graphically on the display unit 2418 as shown in FIG.
The placement speed calculation means 2404 of the personal computer 24 calculates the concrete placement speed from the change in the calculated launch height.
Further, the remaining amount calculating means 2406 of the personal computer 24 calculates the remaining amount required for placing concrete on the mold 10 from the calculated launch height.

Further, in the time measuring means 2408 of the personal computer 24, when the concrete is placed on the mold 10 in a plurality of times, each time the concrete is placed, the next concrete is started from the end of the concrete placement. Measure the time to start placing. At this time, FIG. 5 shows the results of the time for each placement measured by the time measuring means 2408 and the concrete launch height h. The result shown in FIG. 5 is displayed graphically on the display unit 2418.
Further, the cold joint presence / absence judging means 2410 of the personal computer 24 judges whether or not a cold joint has occurred from the measured time. The determination result is displayed on the display unit 2418.

The elapsed time measuring means 2412 of the personal computer 24 measures the elapsed time from the beginning of placing concrete to be placed first when the concrete is placed on the mold 10 in a plurality of times. .
In the graphic display control means 2414 of the personal computer 24, the launch height h of the placement concrete 30 corresponding to the installation location of each level sensor 16 is expanded horizontally as shown in FIG. The placed concrete is superposed on a horizontally developed image and displayed on a display unit 2418 on a monitor.
At the same time, the elapsed time measured by the elapsed time measuring means 2412, for example, 2 hours elapsed, 1 hour elapsed, 30 minutes elapsed as shown in FIG. The display density is color-coded in order as it goes to cast concrete with a short elapsed time. Then, each time the concrete is placed, this color-coded data is displayed on the display unit 2418 by superimposing it on an image formed by horizontally expanding the formwork 10 and the placed concrete.

  Further, the moisture content calculating means 2416 of the personal computer 24 calculates the moisture content of the cast concrete from the change in capacitance generated between the pair of electrode wires 1602 before and after compacting the placed concrete. The calculated moisture content is displayed on the display unit 2418.

  According to the concrete placement management method and apparatus in this embodiment, the level sensor 16 having the pair of electrode wires 1602 is placed at intervals in the circumferential direction in the cylindrical mold 10. It is arranged to extend in the vertical direction, which is the direction of the height of the concrete that rises, and between the pair of electrode wires 1602 of the level sensor 16, a change in the capacitance generated according to the relative dielectric constant of the concrete is caused. The measurement was performed by the measurement circuit 18, and the concrete placement speed and the remaining amount required for placing the concrete on the formwork were calculated based on the measured values. The remaining amount required for placing concrete can be continuously grasped and confirmed in real time. As a result, it is possible to prevent poor placement of concrete into the mold.

  In addition, according to the present embodiment, the total capacitance generated between the pair of electrode wires 1602 increases or decreases in proportion to the amount of placement of the concrete. Therefore, by installing a plurality of such level sensors 16 in accordance with the shape of the mold 10 and the grasped situation, it is possible to grasp the placing situation. Further, by plotting the launch height of the cast concrete two-dimensionally or three-dimensionally as shown in FIG. 6, it is possible to grasp the cast situation continuously in real time.

  In addition, according to the present embodiment, every time concrete is placed in a mold several times, the time from the end of placing the concrete to the start of placing the next concrete is measured. Since it is configured to determine whether or not a cold joint has occurred from the measured time, the presence or absence of a cold joint is confirmed from the time measured between the end of concrete placement and the start of the next concrete placement. can do.

Further, according to the present embodiment, since the moisture content of the cast concrete is obtained from the change in capacitance generated between the pair of electrode wires 1602 before and after compacting the cast concrete, It is possible to grasp the internal moisture content which changes in the process of hardening with the hardening process, and to estimate the hardening strength of the cast concrete. This is useful for strength management and quality control.
Such management makes it possible to form a cured body with stable quality. In addition, it is difficult to visually check the concrete placement status, such as when the concrete placement height is high due to the thin wall structure and the reinforcing bars are placed in an overcrowded state or when the concrete is back-filled so that the concrete is filled upward. In such a case, it is possible to check the status of the process.

  In addition, according to the present embodiment, when the concrete is placed on the formwork divided into a plurality of times, the elapsed time from the beginning of placing concrete to be placed first is measured, The measured height of the cast concrete is displayed on the monitor, and the measured elapsed time is displayed in different colors each time the concrete is placed. The rising situation can be visually grasped and confirmed.

In addition, in the quality control of the placed concrete, it is not always necessary to confirm that the concrete is placed when the concrete is placed, and there are various regulations. Whether or not this is observed also includes the meaning that it can be secured by applying the concrete placement management method and apparatus of the present invention.
For example, there is a standard rule of 40 to 50 cm / hour for concrete placing speed (placement speed). This is to prevent the formation of voids in the space below the reinforcing bars due to concrete subsidence and cracking later if the launch is too fast.
Also, time management when concrete is driven is important. If the next concrete is driven after a predetermined time or more, it will not be integrated, and a problem such as a so-called cold joint will occur. In order to prevent this, the interval until the next concrete is driven is defined as 1.5 hours or 2 hours.
It is also important to know how much concrete has been driven and how much is left for a given quantity. In addition, it is useless if there is not enough material for the cast concrete, and if it is too much, it will affect the cost.

In addition, regarding the measurement of moisture content, it is possible to grasp the situation where soft concrete is still placed and to map it based on the data or to apply it to quality control. For example, the flow of concrete decreases, and there are physical properties expressed in terms of the beginning and end of setting, which is an index of hardness, at the initial stage of hardening (6 to 10 hours after placing). This is an important factor in relation to concrete finishing and bleeding time for water to converge. Furthermore, after it has hardened, there is an index called compressive strength, which can be used as a guideline to determine when the mold has been removed and when the required strength has been achieved. These are all governed by the chemical reaction between cement and water, and by measuring how they are used and reduced in water reactions (ie, the water content in solids and the degree of saturation when solidifying), Predict physical properties.
Such management makes it possible to form a cured body with stable quality. In addition, it is difficult to visually check the filling status of the filling material, such as when the concrete placement is high with a thin wall-like structure and the reinforcing bar is placed in an overcrowded state or when the concrete is turned upside-down. In such a case, it is possible to check the filling state.

  Further, the object of the present invention is positioned as being applied to all concrete works in civil engineering and construction work. Concrete work includes the filling of column members and wall members, which have a relatively high difference in the height of the concrete member, the placement of the tunnel lining concrete top, or the upturning of concrete upwards. This is particularly effective in understanding the placement status of the club.

  DESCRIPTION OF SYMBOLS 10 ... Formwork, 16 ... Level sensor, 1602 ... Electrode wire, 1604 ... Insulating material, 18 ... Measurement circuit, 22 ... Switching circuit, 24 ... Personal computer, 2402 ... Launch height calculation means 2404... Placing speed calculation means, 2406... Remaining quantity calculation means, 2408... Time measurement means, 2410... Cold joint presence / absence determination means, 2412... Elapsed time measurement means, 2414. 2416... Moisture content calculating means, 2418.

Claims (10)

A concrete placement management method for placing concrete in a space extending vertically,
A level sensor in which a pair of electrode wires extending in the vertical direction parallel to each other at a certain interval in the horizontal direction is covered with an insulating material is installed in the void,
As concrete is placed in the void, the height of the concrete placed in the void based on the change in capacitance generated between the pair of electrode wires in accordance with the relative dielectric constant of the concrete Calculate
Calculate the concrete placement speed from the change in the launch height, and calculate the remaining amount required for placing concrete in the remaining space from the launch height,
A concrete placement management method characterized by that.   2. The level sensor is installed in a plurality of positions spaced apart in the circumferential direction in the space, and the height of concrete is calculated for each installation location of each level sensor. The concrete placement management method described. Placing concrete in the void is performed in multiple times,
Each time the concrete is placed, the time from the end of placing the concrete to the start of placing the next concrete is measured, and whether or not a cold joint is generated is determined from the measured time. The concrete placement management method according to claim 1 or 2. Placing concrete in the void is performed in multiple times,
Measure the elapsed time from the start of placing concrete to be placed first,
4. The concrete according to any one of claims 1 to 3, wherein the height of the cast concrete is displayed on a monitor and the elapsed time is displayed in a color-coded manner every time the concrete is cast. Placement management method. Compaction is performed after completion of placing concrete in the void,
The concrete placement management method according to any one of claims 1 to 4, wherein a moisture content of the placement concrete is obtained from a change in capacitance generated between the electrode wires before and after the compaction. A concrete placement management device placed in a space extending up and down,
A level sensor that is installed in the void and is formed by covering a pair of electrode wires extending in the vertical direction in parallel with each other at a certain interval in the horizontal direction with an insulating material;
As concrete is placed in the void, the height of the concrete placed in the void based on the change in capacitance generated between the pair of electrode wires in accordance with the relative dielectric constant of the concrete Launch height calculating means for calculating the height;
A placement speed calculating means for calculating a concrete placement speed from the change in the launch height;
A remaining amount calculating means for calculating a remaining amount required for placing concrete from the launch height to the remaining space;
A concrete placement management device comprising: A plurality of the level sensors are installed in the space at intervals in the circumferential direction.
7. The concrete placement management apparatus according to claim 6, wherein the launch height calculation means calculates the concrete launch height for each installation location of each level sensor. Placing concrete in the void is performed in multiple times,
Time measuring means for measuring the time from the end of placing concrete to the start of placing the next concrete every time the concrete is placed;
Cold joint presence / absence determining means for determining whether or not a cold joint is generated from the measured time;
The concrete placement management device according to claim 6 or 7, further comprising: Placing concrete in the void is performed in multiple times,
Elapsed time measuring means for measuring the elapsed time from the beginning of placing the concrete to be placed first,
Graphic display control means for displaying the height of the cast concrete as a monitor and displaying the measured elapsed time by color for each cast concrete;
The concrete placement management device according to any one of claims 6 to 8, further comprising: Compaction is performed after completion of placing concrete in the void,
A moisture content calculating means for obtaining a moisture content of the cast concrete from a change in capacitance generated between the electrode wires before and after the compaction;
The concrete placement management device according to any one of claims 6 to 9, further comprising:

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