JPH09196890A - Filling state judging method and its device, and filling control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the control of the filling quantity of alkaline material by arranging a pair of electrodes made of materials of different kinds to generate electromotive force when arranged in the alkaline material with an attached extension line to measure voltage. SOLUTION: The filling state judging device is composed of an electrode section 1 where electrodes 11a, 11b made of materials of different kinds are arranged apart from each other, an extension line 12, and a voltage measuring instrument 3. Alkaline materials are cement milk, mortar and concrete. The electrode section 1 is arranged at a place where the charged state of charging material such as concrete or the like shall be confirmed. The extension line 12 is connected to the voltage measuring instrument 3 for measuring electromotive force generated between the electrodes 11a, 11b. When the voltage measured by the voltage measuring instrument 3 enters a fixed value range, the cement is judged to have been filled between the electrodes 11a, 11b, and the quantity of concrete to be placed hereafter can be accurately estimated to accurately control the quantity of concrete.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cement milk,
The present invention relates to a technique for determining the filling state of alkaline substances such as mortar and concrete.

[0002]

2. Description of the Related Art Conventionally, measuring equipment has been used especially for places where visual inspection is impossible, such as tunnel lining, reverse casting method, confirmation of top of concrete such as cast-in-place pile, and confirmation of concrete filling of permanent formwork. It is measured using. This measuring method is based on electric resistance (see Japanese Patent Application Laid-Open No. 7-145613).
Is measured, temperature is measured (see Japanese Patent Laid-Open No. 7-238548), or electromagnetic waves, radiation or sound waves (see Japanese Laid-Open Patent Publication No. 5-295734) are used.

However, the conventional methods have the following problems. <a> The method of measuring the electrical resistance is to place the electrodes at the concrete filling position, pass an electric current between the electrodes, and measure the electrical resistance between them, so the dimensional accuracy between the electrodes, the length of the cable, and the clothing It is difficult to maintain high measurement accuracy because the resistance value changes depending on the insulation state and the optimum measurement frequency. <B> Further, when measuring the electric resistance, it is difficult to identify concrete from the resistance value because the resistance value of water or muddy water also changes arbitrarily. <C> When measuring electrical resistance, connect a cable from the measurement electrode to a measuring instrument such as an ammeter, and a current will flow through it, causing a voltage drop in the middle of the cable
It is necessary to place a repeater in the middle of the cable. <D> In addition, when measuring the electrical resistance, if the filling position of concrete is far from the installation location of a measuring instrument such as an ammeter, it is necessary to connect a cable to the filling position and pass an electric current. In order to improve the accuracy, it is necessary to use an expensive cable such as a shielded wire, which increases the cost and makes it difficult to bury it. <E> In the case of temperature measurement or measurement using electromagnetic waves, radiation or sound waves, there are problems that the device is expensive, the measurement work is complicated, and it is difficult to bury it.

[0004]

[Problems to be Solved by the Invention]

<A> The present invention provides a simple and highly accurate method and apparatus for determining the presence of an alkaline substance. <B> The present invention is to provide a method for easily managing the filling amount of an alkaline substance.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a pair of electrodes of different materials, which generate electromotive force when placed in an alkaline substance, are arranged with a lead wire, and the voltage between the lead wires is measured and measured. When the applied voltage falls within a predetermined value, it is determined that the alkaline substance is filled between the electrodes, or the filling determining method, or in the above filling determining method, the alkaline substance is cement milk, mortar, or concrete. Characterized by a filling determination method, or placed in a predetermined position in the mold by attaching a lead wire to a pair of electrodes of different materials that generate electromotive force when placed in an alkaline substance,
Measure the voltage between the lead wires and manage the amount of alkaline substances filled in the mold, or a filling management method, or attach a lead wire to a pair of electrodes of different materials that generate electromotive force when placed in cement. It is in a filling determination device that determines that cement is filled between a pair of electrodes when the voltage measured by the voltmeter is within a predetermined value by connecting a voltmeter between the lead wires. .

[0006]

Embodiments of the present invention will be described below with reference to the drawings. <A> Principle of detection of alkaline substance As shown in FIG. 1, when a pair of electrodes 11a and 11b made of different materials are separately arranged in an alkaline substance 2, particularly a strongly alkaline substance, the difference in contact potential is caused as in the alkaline battery. An electromotive force is generated between the electrodes 11a and 11b. The value of this electromotive force is determined by the type of electrodes 11a and 11b and the type of alkaline substance 2. As the alkaline substance 2, for example,
Although there are various substances such as water glass-based chemicals and cement, the cement will be mainly described below as an example.

When the different kinds of electrodes 11a and 11b are previously spaced apart and filled with cement-containing substance such as cement milk containing cement, mortar or concrete, the electrodes 11a, 11b 1
A predetermined electromotive force is generated during 1b. Therefore, the electromotive force is measured by the voltage measuring device 3 to determine the presence of the filled substance. In this measurement, the voltage can be measured with almost no current flowing through the voltage measuring device 3, so that a voltage substantially the same as the electromotive force is generated in the measuring section of the voltage measuring device 3, and accurate measurement is possible.

Even if ground water or muddy water is injected between the electrodes 11a and 11b, a large electromotive force is not generated, and even if a substance different from the substance to be filled, such as cement, is filled between the electrodes 11a and 11b. Since the electric power is different, the substance to be filled and the different substance can be distinguished from each other.

<B> Filling determination device The filling determination device is, for example, as shown in FIG.
an electrode portion 1 in which a and 11b are arranged apart from each other, and an electrode 11
It is composed of a lead wire 12 that is electrically connected to a and 11b and guides an electromotive force, and a voltage measuring device 3 that measures the voltage led from the lead wire 12. The voltage measuring device 3 may be an ordinary voltmeter, and in order to improve the accuracy, it is preferable that it be a device that can measure with almost no current flowing, a device that can record the time course of the voltage, and a device with an appropriate display device. Is convenient.

<C> Electrode Section The electrode section 1 can be used with a pair of electrodes 11a and 11b having various shapes such as a plate shape and a bar shape capable of generating electromotive force, and the lead wire 12 is electrically connected to the electrodes 11a and 11b. It is connected. For example, in the case of the small-sized electrode portion 1, the film-shaped or piece-shaped electrodes 11a and 11b may be attached on a thin insulating substrate, or the electrodes 11a and 11b may be formed by vapor deposition. Since the interval between the pair of electrodes 11a and 11b may be arbitrary, the electrode part 1 can be easily manufactured.

The lead wire 12 requires almost no current and has a low voltage, so that a thin and inexpensive coated wire can be used. The material of the electrodes 11a and 11b is a pair of electrodes 11a and 11b that can generate an electromotive force in an alkaline substance.
It is sufficient that one electrode 11a contains, for example, aluminum, magnesium, zinc, or an alloy thereof, and the other electrode 11b contains, for example, stainless steel, carbon, iron, nickel, tin, lead, A material containing copper, silver, platinum, or an alloy thereof can be used.

When aluminum and stainless steel are used as a pair of electrodes, an electromotive force of about -1200 mV is generated with respect to an alkaline substance, ultra-high fluidity concrete, and -250 mV with respect to cement milk having a water-to-cement ratio of 1: 1. Was generated, and only −50 mV was generated with respect to water. Also,
When aluminum and iron are used as electrodes, -300 mV is generated, and when aluminum and brass are used as electrodes, -200 mV is generated.
mV occurred. However, iron has a drawback in that it causes rust.

The measurement of the filling state of the filling substance will be described below. <B> Arrangement of filling determination device The electrode unit 1 is arranged at a place where it is necessary to confirm the filling state of a filling substance such as concrete. In FIG. 3, a tunnel is formed by the buried form 41, and the space between the buried form 41 and the ground is filled with concrete. In order to measure the filling state of the concrete, the electrode part 1 is arranged at the upper part required for the measurement. The lead wire 12 is drawn from the electrode portion 1 and connected to the terminal of the voltage measuring device 3 to measure the electromotive force generated between the electrodes 11a and 11b. The electrode unit 1 used here is
I will make it to the buried state.

FIG. 4 shows an arrangement state of the electrode portion 1 when the filling state of concrete is measured in the Sakamaki method. In addition to this, wherever you want to know the filling state of the filling material such as cement milk, mortar or concrete, such as filling concrete in cast-in-place piles, or the measuring point where the electrode part 1 cannot be collected or the voltage. It is possible to measure even at a measurement point several hundred meters away from the measuring instrument 3.

FIG. 5 shows a method for controlling the filling amount of concrete poured into the formwork 4. The electrode part 1 is arranged in advance at a predetermined location in the form 4, and the voltage is measured by the voltage measuring device 3 while concrete is being placed in the form 4. When the voltage is measured, it is possible to more accurately predict the amount of concrete to be placed in the future from the filling amount of the concrete filled up to that point, and it is possible to accurately manage the concrete amount. By arranging the electrode parts at a plurality of places, the concrete pouring amount can be managed in more detail.

<B> Measurement of electromotive force An example of measuring the electromotive force generated when concrete is placed by placing electrodes on the inner wall surface of the tunnel is shown below. In this measurement, the electrodes used were aluminum and stainless steel. In the concrete component, the cement is fly ash mixed mascon type blast furnace cement 20 # [FMKC-20] manufactured by Daiichi Cement Co., W / C is 41.5% by weight and S / a is 56.7% by weight. Is. 170 kg of water
/ M ³ , cement 410 Kg / m ³ , fine aggregate 950
Kg / m ^3, coarse aggregate is 729Kg / m ^3, SP-8S
X2 is 9.83 Kg / m ³ , SFCA2000 is 0.2
0 kg / m ³ was used. As the voltage measuring device 3, a strain voltage measuring device (TSD-601) manufactured by Tokyo Sokki Kenkyusho Co., Ltd. was used.

FIG. 6 shows changes in the voltage measured by the voltage measuring device 3 with respect to the electromotive force generated between the electrodes. In FIG.
An electromotive force of about -100 mV is generated from around 12:00, and the electromotive force is rapidly changed from about -100 mV to about -1100 to -1200 mV around 0:00 to 1:00, and this voltage is maintained. . This means that when the voltage changes, the electrode part 1 is filled with concrete and the space between the electrodes is -1200.
This shows that an electromotive force of about mV is generated.

It is considered that the cause of the electromotive force of about -100 mV is caused by the ground water droplets adhering to the electrode portion 1. An electromotive force is generated when a small amount of electrolyte is contained. The noise before detecting concrete is considered to be the drop of water droplets adhering to the electrode part 1, and the noise after detecting is considered to have occurred when wood chips such as sheet piles poured onto the concrete contact the electrode part 1. To be

[0019]

According to the present invention, the following effects can be obtained. <B> Since the specific electromotive force that is determined by the alkaline substance such as concrete and the electrode substance is measured, the electromotive force is different from the water or muddy water that is not the measurement target, and the presence or absence of the measurement target substance is identified. be able to. <B> Since a small electric potential is measured without passing current, the lead wire is as long as several hundred meters, and even with an inexpensive cable, there is no leakage current, there is no effect of voltage drop, and there is no need to install a repeater. The electromotive force generated between them can be measured as it is. <C> Since the electromotive force generated between the electrodes is not affected by the electrode spacing, the voltage can be accurately measured regardless of the shape of the electrode portion and the manufacturing accuracy. <D> Since the electrode portion can be made small and inexpensive, and the lead line can be made thin and inexpensive, the electrode portion and the lead line can be buried. <E> By arranging electrodes at appropriate placement points where it is certain that the alkaline filling material such as concrete will reach, it is possible to check the arrival status of the filling material such as concrete and the required amount of placement as needed, and manage the construction. can do. <F> By placing electrodes at appropriate places where it is difficult for alkaline filling materials such as concrete to reach, it is possible to check the filling of filling materials such as concrete and control the quality of finished products. .

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of the present invention.

FIG. 2 is a diagram showing a filling determination device of the present invention.

[Fig. 3] Measurement diagram of concrete to be filled outside the buried formwork

[Fig.4] Measurement diagram of concrete filled by Sakamaki method

[Fig. 5] An explanatory diagram of placement amount management

[Fig. 6] Graph for measuring the filling state of concrete

Claims (4)

[Claims] 1. An electromotive force is generated when placed in an alkaline substance. A pair of electrodes made of different materials are arranged with a lead wire, the voltage between the lead wires is measured, and the measured voltage is within a predetermined value. When entering, it is determined that the alkaline substance is filled between the electrodes. 2. The filling determination method according to claim 1, wherein the alkaline substance is cement milk, mortar, or concrete. 3. A pair of electrodes of different materials, which generate electromotive force when placed in an alkaline substance, are provided with lead lines and placed at a predetermined position in the mold, the voltage between the lead lines is measured, and the mold is A filling management method that controls the amount of alkaline substances filled inside. 4. A pair of electrodes of dissimilar materials that generate electromotive force when placed in cement are arranged with lead wires attached, a voltmeter is connected between the lead wires, and the voltage measured by the voltmeter is predetermined. When it is within the value, it is judged that the cement is filled between the pair of electrodes.