JPH0436444Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an electrode used for measuring moisture in concrete, mortar, etc.

(Prior art) After placing concrete, mortar, etc. (after pouring ready-mixed concrete), measuring fluctuations in the amount of water contained in it is necessary for the next process, such as painting internal and external walls; floor coating work, etc. This is important when performing waterproofing work, sealing work, interior work, etc. Furthermore, the moisture that evaporates from concrete or mortar has a great effect on the humidity conditions inside the building after completion, and it is important to measure the amount of moisture inside to predict this.

Conventionally, when measuring moisture in concrete, mortar, etc., the electrode surface is applied to the surface of the concrete or mortar, and the amount of moisture in the concrete or mortar is measured based on the change in electrical resistance measured at that time. There is. However, this method can only measure areas very close to the surface and cannot measure internal moisture. Furthermore, even when measuring by drilling a hole in concrete that has hardened to some extent and embedding an electrode, the problem of poor contact occurs as the hole expands over time.

(Problems to be solved by the invention) Therefore, the present invention solves the above-mentioned problems of the conventional moisture measuring electrode for concrete, mortar, etc., and also provides a simple and convenient electrode for measuring moisture in concrete, mortar, etc. The purpose is to

(Means for Solving the Problems) In order to solve the above problems, the present invention buries two electrodes at a predetermined interval d when concrete, mortar, etc. has not hardened after being poured. . The present invention is characterized in that an electric moisture meter is electrically connected to the electrode to measure the amount of moisture in the structure such as concrete or mortar. However, concrete or mortar after pouring dries over time, and as the drying progresses, gaps develop between the contact surfaces of the electrodes and the concrete, resulting in poor contact. This will increase contact resistance and cause measurement errors.

The present invention is an electrode intended to prevent the above-mentioned drawbacks.

The electrode according to the present invention is made of conductive rubber in the shape of an inverted tapered rod, and a lead wire is connected to this.
If a gap occurs between the electrode and the concrete as the concrete dries, the conductor rubber can be crimped to the concrete by pulling and twisting the electrode part. Furthermore, if the concrete dries and gaps occur, it can be crimped again in the same way.

(Function) As mentioned above, the electrode of the present invention is made of conductive rubber with a slightly expanded structure at the tip, so even if poor contact with the electrode occurs as the concrete or mortar dries, the electrode can be pulled out each time. If you keep it tensioned, the elasticity of the rubber will always maintain the same contact state. According to experiments, this drawing gap l is 2 to 3 mm, and there is no problem of variation in interelectrode resistance due to a decrease in contact area.

(Example) FIG. 1 is a sectional view showing the structure of the concrete/mortar moisture measuring electrode of the present invention. Reference numeral 1 denotes a conductive rubber electrode part, and the tip part (lower part in the figure) is slightly thicker than the root part, and in the example, it is about 1 mm larger. A cord 2 for extracting electrical signals is attached to the electrode 1. Code 2 is electrode 1
The screw 5a and the lug plate 5b are fixed to the center of the
is soldered to. A holder 3 has the effect of reinforcing the connection between the electrode 1 and the cord 2, and the tip of the holder 3 (lower side in the drawing) is screwed and fixed to the electrode 1. Figure 2 shows ○+ and ○- electrodes 1 at a constant depth on the concrete surface with an interval d.
The cord 2 is connected to an electric resistance moisture meter (not shown).

Fig. 3a shows the electrode 1 immediately after being buried, and Fig. 3b shows the electrode 1 pulled out after drying over time. l is the gap created at that time.

(Effects of the invention) As explained above, the concrete/mortar moisture measuring electrode of the present invention has a thick tip made of conductive rubber, so the concrete/mortar dries over time, preventing contact between the electrode parts. Even if it gets bad, by pulling it out, the elasticity of the conductor rubber will improve the contact again, allowing stable measurements.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a conductive rubber electrode for measuring moisture content in concrete and mortar according to the present invention. Figure 2 shows the measurement state, and Figure 3a
The figure shows the state immediately after burying, and FIG. 3b shows the state after the concrete and mortar have dried to some extent and the electrode 1 has been pulled out. 4... Cord stopper, 6... Cord stopper set screw, 10... Concrete, mortar, l
...Gap when electrode 1 is pulled out.

Claims (1)

[Scope of utility model registration request] Regarding the electrodes of an electric moisture meter used to measure moisture by burying two electrodes at a predetermined distance in concrete, mortar, etc., the buried part of the electrodes is
An electrode for measuring moisture in concrete and mortar, which is made of conductive rubber and has a circular cross section, and is characterized by a shape that becomes slightly thicker toward the tip.