JPS60227370A - Ground pole of ground resistance reducing agent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to grounding used for safety facilities of various electrical equipment, and when installing a grounding electrode, the desired low grounding resistance value can be obtained because the soil has a high specific resistance value. This method differs from the conventional method of infiltrating a water-mixed slurry of a reducing agent into the soil to reduce ground resistance. It relates to a reducer pole that provides resistance.

According to conventional technology, in such cases, in ancient times, the goal was to be achieved by replacing the soil with soil with a lower resistivity value, or by driving a strong grounding pole deep into the stratum with a lower resistivity value. Both methods required large construction costs and lacked practicality, so research was conducted to reduce ground resistance by improving the soil using bentonite, ammonium sulfate, etc. As a result, reducing agents were developed and became popular. It came to be put into practical use in
child.

The reducing agent varies depending on the soil quality, but it is 7 to 10 to 30 per pole.
As shown in Figure 1, diameter 50~75Cr,
A hole 1 (hereinafter referred to as a specified hole) with a depth of 80 cIn is dug, a ground electrode 2 is driven from the bottom of the hole, and a water-reducing slurry 3 mixed with water is poured in, allowed to harden, and then backfilled.

The reducing agent 3 permeates downward and permeates and hardens the soil around the ground electrode to form a reducing soil layer 4 and obtain a low ground resistance value.

There are three more advanced methods for burying ground electrodes to reduce ground resistance through soil treatment with this reducing agent, examples of which are listed below.

One of them is the so-called complete hole burying method, as shown in Figure 2, in which a required hole 5 is dug with an excavator, a ground electrode 2 is inserted, and a water-mixed slurry of the reducing agent is exposed on the ground surface 6. The material is poured into the hole, left to harden, and then backfilled.

In addition, as shown in Fig. 3, by using the so-called rate casting method, a specified hole 1 is pre-drilled.
A concrete pipe (not shown) into which the grounding electrode 2 is inserted is placed from the bottom of the ground electrode, the pipe is removed at a predetermined depth, and a water-mixed slurry 3 of the reducing agent is poured into the specified hole 1. It is poured into the bottom, allowed to harden, and then backfilled.

Next, as shown in Fig. 4, using the so-called complete pouring method, the ground electrode 2 is immediately poured from the ground surface 6 using a pouring pipe (not shown) into which the ground electrode 2 is inserted, and only the same groove is placed at the required depth. A water-mixed slurry of a reducing agent is poured into the hole through the opening of the hole exposed on the ground surface 6, and after it hardens, it is backfilled.

In addition, Figure 5 shows the complete pouring method, but in the case of a light pole, a strong light ground electrode 7 is driven directly into the ground, and a pouring pipe (not shown) is added just before it sinks into the ground. The concrete is driven further, and when it reaches a predetermined depth, only the concrete pipe is pulled out, water-mixed slurry as a reducing agent is poured into the hole opening at the ground surface 6, and after it hardens, it is backfilled.

These construction methods are selected depending on conditions such as the soil quality of the construction site and the desired ground resistance value, but in any case, when injecting the reducing agent, the cavities 5 and 8 in the hole have sufficient fluidity. In addition, a considerable amount permeates into the surrounding soil and hardens to form the reduced soil layer 4, thereby achieving the intended purpose.

In this way, in FIG. 1, the reducing agent penetrates into the soil around the ground electrode 2 to form a reducing layer 4, and in FIG. In Fig. 3, a reduction layer 4 in which a reduction agent has permeated into the soil around the ground electrode 2 is formed in a cavity formed by the removal of a pipe for installation around the ground electrode 2, and a gel body 5 in which the reduction agent has hardened, and a prescribed bottom layer above it. In Fig. 4, a reduction layer 4 in which a reducing agent has penetrated into the gel body 3 and the soil around the hole is formed, and in Fig. 4, a gel body 5 containing a hardening agent and a reducing layer 4 are formed in the cavity where the installation pipe was removed around the ground electrode 2. The reduction layer 4 in which the reduction agent has penetrated into the soil around the hole is the grounding electrode 7 of the lamp in Figure 5.
A gel body 8 in which the reducing agent has hardened is formed in the cavity formed by the removal of the pouring pipe above the gel body, and a reducing layer 4 in which the reducing agent has permeated into the soil around the gel body 8 is formed.

However, depending on the content of soil such as clay, sand, and cobblestones,
Since their porosity and moisture content vary greatly, the desired reduction effect cannot be expected unless the amount of reducing agent used and the amount of water mixed are changed significantly depending on the soil quality.

In addition, the timing of pouring and backfilling varies greatly depending on the temperature, and if the timing is incorrect, the quality of the gel body will deteriorate and the desired reduction effect will not be achieved.

Since the above-mentioned matters are underground matters that cannot be seen with the naked eye, the results of the construction work must be extremely uncertain due to the collapse of the hole. Therefore, the reduction effect is also uncertain, and there is a drawback that the obtained ground resistance values vary widely.

The reduction rate of test values at a certain testing laboratory is as follows.

Number of tests: 15 Maximum value: 71.5% Minimum value: 13.1% Variation: 58.4% Average value: 45.2% The present invention is a grounding electrode invented from such a conventional viewpoint, and the object of the invention is to use a reducing agent. It is made by hardening and molding water-mixed slurry into a column shape, into which a vertically long plate, bar or wire made of a highly conductive metal is penetrated vertically, and a lead wire is fixed to the top end of this metal. This provides a rod-shaped ground electrode that exhibits a reduction effect.

If you use wire, you can use a long one including the lead wire.

Since this reducing agent pole rod is mainly made of hardened reducing agent, it cannot be directly driven into the ground due to its strength, but it can be inserted into a hole dug by an excavator, or a By holding it in the driving pipe of the driving tool, it is possible to safely drive the reducing agent pole rod without applying any force directly to it, and it is possible to securely insert the rod of the desired length to the desired depth. This allows you to reliably obtain the desired low ground resistance.

In addition, this reducing agent pole rod shall be of a length that does not pose a problem in handling, and shall be used by adding additional rods as needed. Therefore, the reducing agent pole rod shall be placed on a straight line in the vertical direction so that it can be joined easily. The upper surface 11 of the reducing agent pole rod is formed with a concave or convex conical or spherical surface, and the lower surface 12 is formed with a correspondingly convex or concave conical or spherical surface of the same shape and size.

Also, provide grooves 10 and 15 in the vertical direction on the side and top surfaces to accommodate the lead wires of the lower ones so that they can be guided upwards when the parts are added. Instead of this groove, a vertical hole (not shown) may be provided inside.

Another type of such supplementary reducing agent pole rod is a hardened and molded reducing agent having only a vertical hole through which the lower lead wire 16 can be guided upward.

Since all the lead wires can be bundled above ground, there is no problem with corrosion or other problems underground, and a consistently low ground resistance value can be obtained.

An example of the implementation of the present invention will be described in detail with reference to the drawings.
Fig. 6 shows the structure of the reducing agent pole rod of the present invention, which is made by hardening and molding a water-mixed reducing agent slurry into a columnar shape, into which a mild steel wire 14 is vertically penetrated. The upper part of the mild steel wire 14 is extended long to form a lead wire 9.16, and the lower part is bent beforehand to prevent it from being pulled out.

Further, the upper surface is formed into a concave conical surface 11, and the lower surface is formed into a convex conical surface 12 of the same shape and size.

Further, a groove 10 is provided on the side surface and a groove 15 is provided on the top surface.

FIG. 7 shows a case in which two of these reducing agent poles are added, and the lead wire 16 of the lower reducing agent pole is guided upward through the groove IO on the side surface of the upper reducing agent pole. It is tied to the lead wire 9 on the ground.

Figure 8 shows the structure of another reducing agent pole rod, which is made by hardening and molding a water-mixed reducing agent slurry into a columnar shape.
A mild steel wire 14 is inserted vertically into this interior, and the upper part is a lead wire 16, or only a vertical hole 17 is provided inside, and if it is added, the lower lead wire is inserted in the middle of casting. 16 is passed through the vertical hole 17 of the upper one and led upward, and after being placed on the lower reducing agent pole rod, the water-mixed slurry of the reducing agent is injected into this hole and the casting is resumed.

Fig. 9 shows a state in which two reduced agent pole rods 18 of the present invention are added and cast from the bottom of the specified hole 1, and Fig. 10 shows a state in which they are similarly cast directly from the ground surface, and are backfilled after burial. .

Backfilling is best done with water-mixed soil.

Next, to explain the effects of the present invention, since the reducing agent pole rod of the present invention can be hardened and molded by pouring a water-mixed slurry of the reducing agent into a mold, a large amount of the reducing agent is prepared in advance at the factory under favorable conditions. Since it can be produced, high quality and inexpensive products can be obtained.

Since the reduced agent pole rod thus produced is buried underground, it can be used regardless of the soil quality or even if the hole collapses after the casting or seib is removed, unlike the previous injection method. Unlike previous injection methods, the desired low ground resistance is reliably achieved because the required amount of high-quality cured reducer is reliably implanted at the required depth.

This method does not create a reduction stratum), so the reduction effect should be worse than the conventional injection method, but because the burial reliability is superior, the experimental results are as follows: Obtained results with no reduction rate.

Number of experiments: 12 Maximum value: 7287% Minimum value: 32.2% Variation: 40°5% Average value: 54.2% The amount of reducing agent used is also reduced by the amount that permeates into the soil, and is about one-fifth of the conventional method, making the cost extremely low. .

Next, since the present invention involves burying solid materials, there is no need for conditions regarding the timing of pouring and backfilling, and the time required for on-site construction is correspondingly shortened, so efficiency is greatly improved and construction costs are reduced.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing the state after the reduction side has been treated using the basic method, and Figures 2 to 5 are after the ground electrode has been buried using an excavator and a pouring pipe and then treated with a reduction agent. It is a sectional view showing a state. FIG. 6 shows the structure of the reducing agent pole rod of the present invention, where A is a side view and the mouth is a top view. FIG. 7 shows the addition of two reducing agent poles. Figure 8 shows the structure of another reducing agent pole, showing A, C,
2 shows a side view, and 2 shows a top view. FIG. 9 and FIG. 1θ are cross-sectional views showing the state in which the reducing agent pole rod 18 of the present invention is embedded. The blank area indicates the backfilling area after filling is completed. Patent applicant Sadako Tada +313 i q

Claims (1)

[Scope of Claims] (1) A product formed by hardening a slurry of a ground resistance reducing agent (hereinafter simply referred to as a reducing agent) mixed with water into a columnar shape, with a vertical plate made of a highly conductive metal inside. A ground electrode (hereinafter simply referred to as a reducing agent pole) formed by hardening and molding a water slurry of a reducing agent characterized by an acid. (2) Grooves (10, 15) or holes (, +1 (not shown)
A replenishable reducing agent pole rod (hereinafter simply referred to as a replenishing reducing agent pole rod) characterized in that it is provided in the vertical direction. (8) Concave or convex conical surface on the upper surface of the reducing agent pole rod (11)
Alternatively, a reducing agent pole rod characterized in that a convex or concave conical surface (12) of the same shape and size or a spherical surface is molded on the lower surface. (4) The water-miscible slurry of the reducing agent is hardened into a column shape, and there is only a vertical hole (17) that can accommodate the lead wire (16) of the reducing agent pole rod attached below. A pole rod of a joint reducing agent characterized in that it is provided through the rod.