JPS5866856A - Measuring method for flow of ground water - Google Patents

Abstract

PURPOSE:To make the properties of soil coincident with those of ground water strata and to measure the flow of the ground water with high accuracy by providing measuring electrodes and an electrolyte injecting pipe of double construction in an observing part, injecting pressure water, burying the observing part and detecting the flowing of an electroyte with the electrodes. CONSTITUTION:An electrolyte injecting pipe 12 and measuring electrodes 13-28 of double construction are provided in the observing part 11 of a probe 4 and are so designed as to deliver pressure water. The electrodes 13-28 consist of 8 sets of inside and outside electrodes which are disposed concentrically. In the stage of measurement, the probe 4 is brought downward and pressure water is injected near the holes of the bottoms whereby the part 11 is buried into ground water strata. Then an electrolyte is run from the pipe 12. When the electroyte arrives at the electrode group on account of flowing of the ground water, a change in the resistance value is detected with the change in voltage. The flowing direction is known from the electrode direction of the set by which the peak of said voltage is detected, and from the time when the same arrives at the electrode, the velocity of flow is detected. Therefore roughly the same flow as that of the ground water is obtained and the flow is measured with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring underground water flow, and particularly to a method for measuring underground water flow suitable when the measurement is carried out by being installed in a poling hole or the like.

In recent years, the use of groundwater has become increasingly important in the field of civil engineering and construction, when deciding whether or not to adopt freezing methods for soft ground, and when investigating groundwater contamination. There is an increasing need to accurately measure flow (velocity and/or direction). Conventionally, the so-called trainer method has been widely used as a method for measuring groundwater flow. This method involves drilling multiple poling holes, injecting salt or dye into one of the holes in the center, and examining changes in electrical resistance or concentration over time between the other poling holes, and determining the arrival time and the change in concentration. It measures and calculates flow from position. However, in the above-mentioned conventional technology, it is necessary to drill many mailing holes, and the survey cost is extremely high. (At the same time, when the groundwater flow rate at the measurement point is slow, it takes a long time to perform the measurement, and during that time, it is necessary to drill many mailing holes.) Underground water flow often changes due to factors such as groundwater flow, etc., which has the essential drawback of making accurate measurements difficult.

On the other hand, in recent years, as an attempt to improve the drawbacks of the above-mentioned conventional techniques, a method has been devised in which the flow of groundwater can be measured inexpensively and quickly by simply drilling a single poling hole. This can be done, for example, by lowering a propeller-type current meter as a measuring means into the poling hole and measuring the flow direction and flow velocity from the rotational speed of the propeller and its changes;
Also, as in the invention disclosed in Japanese Patent Publication No. 45-25029,
A disk is lowered into a poling hole, and the groundwater flow condition is estimated from the pressure difference due to the upward and downward flow of water in the hole acting on the disk.

However, in all of the above conventional techniques, the flow is measured by treating the flow of water inside the poling hole as the flow of groundwater, but when groundwater flowing in the ground such as a gravel layer reaches the inside of the poling hole, The frictional resistance (soil properties against groundwater flow) becomes discontinuous within the poling hole, resulting in turbulent flow. Therefore, the relatively small diameter of the poling hole (IIC) causes the flow to increase even when the groundwater flow velocity is extremely small. This method had the disadvantage that accurate flow measurement was difficult.

Furthermore, in the method of driving a mechanical measuring means using groundwater, when the flow velocity is as small as 2 cm per second or less, it is almost impossible to measure the flow velocity or flow direction due to the influence of frictional force and the like.

The present invention has been made in view of the shortcomings of the prior art, and is capable of easily and highly accurately measuring the flow of groundwater having an extremely small flow velocity at a single measurement point. The purpose is to provide a method for measuring flow.

The present invention provides an observation section equipped with a plurality of measurement electrodes, and lowers the observation section into a predetermined groundwater layer in a poling hole drilled into the ground, and during or before and after the descent of the observation section. After partially collapsing the hole wall near the depth to be tested and burying the observation section in the ground, a replacement fluid mass with electrical or chemical properties different from that of groundwater is introduced into the groundwater flow. Accordingly, the present invention aims to achieve the above object by causing a flow in the observation section and detecting and calculating changes in electrical or chemical properties caused by this flow using the measurement electrode. One embodiment will be described based on FIGS. 1 to 13.

FIG. 1 is a schematic explanatory diagram showing an example of actual measurement using a flow measuring device constructed based on the underground water flow measuring method according to the present invention. In the figure, reference numeral 1 indicates a measurement poling hole drilled in the ground E from the ground surface to a predetermined depth into the groundwater layer (fine sand layer, medium sand layer, etc.). A casing 2 is driven into the side wall of this poling hole 1 to a point above the measurement depth, and this casing 2 prevents collapse of one side wall of the hole and blocks the stratum to be measured from other strata. It is about to be carried out.

A measuring probe (hereinafter simply referred to as a "globe") 4, which is an example of a flow measuring device, is suspended in this poling hole 1 via a boring rod 3, and is lowered to the test depth. An observation section installed at the bottom of the hole is inserted and buried in the bottom wall of the hole IB. here,
The direction of the probe 4 is confirmed by a compass needle 5 (see FIG. 2) built into the upper part of the probe 4.
It is designed to be installed and fixed in a predetermined direction.

In the groundwater layer in the ground E, there is a flow of groundwater as shown by the arrow F in the figure, and groundwater W gushes out from the groundwater layer in the poling hole 1. Glove 4 will be immersed.

The probe 4 is mechanically and electrically connected to an external measuring device (not shown) through a hose 6.7 and a cable 8 extending inside the boring rod 3. It is now possible to measure and locate groundwater flow.

FIG. 2 shows the specific configuration of the above-mentioned globe 4. In this figure, 9 is a cylindrical probe body fixed to the lower end of the polling abutment 3, and the probe body 90 has a lower end. The head board 1 made of insulating material is
0 is set.

The lower surface side of this head panel 10 is a space to be measured of groundwater flow, that is, an observation section 11 (see the two-dot chain line in Fig. 2). A spout pipe 12 for discharging the replacement fluid and electrode rods 13 to 28 for measuring groundwater flow are protruded from the former spout pipe 12, and a discharge pipe 12 that has different electrical or chemical properties from the groundwater to be measured is provided. Displacement fluid (e.g. electrolyte such as NaCj solution if groundwater has low conductivity, or
If the conductivity is relatively high (containing aCJ, etc., use pure water, etc.), and the movement of this displacement fluid mass can be measured from the latter electrode rods 13 to 28. The observation unit 11 configured in this manner is installed in the hole bottom wall 1B of the polling hole 1, as will be described later. In addition, when burying the observation part 11, each pouring pipe 1
2 and the electrode rods 13 to 2B, the water supply distributor 29 is a main part of the fluid ejection mechanism for ejecting fluid (water, etc.) from the electrode rods 13 to 2B.
It is built into the probe body 9. This water distribution device 2
9 is connected to the first hose 6;
When pressurized water is injected from the outside through the hose 6, each outlet pipe 30. and 31.31. - The probe body 6 is equipped with the above-mentioned direction meter 5 housed above the water distribution device 29, and its direction signal is sent to the cable B. Next, each configuration of the probe 4 will be explained in more detail.

The head board 10 has bolts 32, 32. - is screwed, thereby sealingly mounting the probe body 9. This head board 1
The spouting pipe 12 is implanted and fixed in the center of the wig part 1 in a vertically penetrating state, and its lower end is inserted into the inside of the wig part 1.
It is extended inside. This pouring pipe 12 is formed into a double pipe shape as shown in FIG. On the other hand, the upper end of the outer tube 34 is bent and closed toward the inner tube 30, and the vicinity of the upper end inside the pro-nib main body 9 is exposed from the outside through the Darling rod 3 as shown in FIG. A nozzle member 36 is fitted to the lower end of the spouting pipe 12, which is connected to the introduced second hose 7 via a check valve 35. Correspondingly between the inner pipe 30 and the outer pipe 34, there is a pressure water spout 36A and a substituent liquid spout 36B, 36.
B, -. are drilled (see Figure 7). These replacement liquid spout ports 36A, -.
The porous member 36C9 is slightly inclined inward and fitted with a porous member 36C9 for preventing foreign matter from entering the inside.

In the spouting pipe 12 formed in this way, when aqua regia is sent out from the outside via the first hose 6, the inner pipe 3
After 0t, aqua regia is jetted downward from the pressurized water spout 3tA provided at the lower end of the spouting pipe 120. At this time, if the spout pipe 12 is lowered downward at the same time, the jet flow from the 36 pressurized water spouts collapses and weakens the hole bottom wall IB near the spout pipe 12. 12 can be gradually inserted and buried in the bottom wall of the hole. On the other hand, when a predetermined amount of replacement liquid is supplied from the outside via the second hose 7, the replacement liquid spout 36B provided at the lower end of the spout pipe 12;
The replacement liquid is poured into the observation section 11 from...

Here, when the replacement liquid is introduced with the observation part 11 installed in the hole bottom 111B, the porous member 36
If the flow of groundwater, which is the object to be measured, is disturbed due to the existence of C and a groundwater aquifer, the displacement liquid is poured out quietly and in a stable state to form a desired mass of displacement fluid. becomes possible.

On the other hand, the electrode rods 13 to 28 are implanted and fixed in a state that penetrates the head plate 10 in a concentric and radial manner centering on the above-mentioned spouting tube 12, and furthermore, the electrode rods 1
The lower ends of the pipes 3 to 28 extend below the spout pipe 12. In terms of variant, it is the 38th! As shown in IIK 5, outer electrode rods 13 to 20 are arranged concentrically and at equal intervals around the leaching tube 12, and inner electrode rods 21 to 28 are arranged in correspondence with the outer electrode rods 13 to 20. They are also arranged concentrically at equal intervals. For this reason, in the embodiment shown in FIG. 3, the electrode rods are arranged radially in eight directions with the extraction tube 12 as the center.

Each of the electrode rods 13 to 28 has exactly the same structure. Of these, the electrode rod 13 will be explained. As shown in FIG. It consists of an equipped outlet pipe 31.

This outlet pipe 31 is connected to the water supply distributor 2 via a check valve 39.
It is connected to 9. A truncated cone-shaped nozzle member 40 is fitted onto the tip of the electrode rod 13, and the lead-out tube 31h is attached to the tip surface and inclined surface of the nozzle member 40.
Pressure water spouts 40A, 40A are connected to each other.

... are drilled (see Figure 5). Therefore, a jet flow is generated downward from the tip of the electrode rod 13, and the electrode rod 13 can be buried in the hole bottom wall IB in exactly the same manner as the spout pipe 12 described above. On the other hand, an electrode 13A is provided near the lower end of the electrode rod 13 and slightly below the spouting tube 12 around the insulation coating 38 described above. This electrode 13A is connected to the probe body 9 by a lead wire wired in a long groove 41 carved in the cylindrical member 37.
It is connected to cable 8 inside. That is, a terminal plate 42 for connecting each of the electrodes 13A to 28A to an external circuit is attached to the lower surface of the water distribution device 290, and the end of the cable 8 described above is fixed to this turnal plate 42. The electrodes 13A to 28A are individually connected to a signal detection display means (not shown) provided externally.
It is designed to connect to. Electrode 13 in the long groove 41
A shielding material 43 is fitted into the portion corresponding to A, so that the inside of the long groove 4o is sealed. By the electrode rods 13 to 28 configured in this #/c manner, the *measuring section 11 is formed in the vicinity of the electrode rods 13 to 28, and the electrode rods 13 to 28 portion is located inside the hole bottom wall IB. When installed, the inside and outside of the scissors observation section 11 are integrally filled with soil forming an underground water layer, and the observation section ll
The soil properties within the balustrade are approximately the same as those within the groundwater aquifer, and therefore, the flow of groundwater moving within the railing 11 is the same as the flow of groundwater within the actual groundwater aquifer.

Among the electrodes $13A to $28A, there are unidirectional electrodes, for example, 13 outer electrodes and 21 inner electrodes.

25 and the outer electrode 17A constitute a set of measuring electrodes, and at the same time the inner electrode 21A, 25 are electrically connected to each other and, for example, to take advantage of the difference in resistivity between the displacement fluid and groundwater. In this case, as shown in FIG. 8, the resistance (liquid resistance) RXst between the one outer electrode 13A and the one inner electrode 21A installed in close proximity to the pair of fixed resistors it and R is and the other inner electrode 21SA
and the other outer electrode 17A are bridge-connected, and after applying a predetermined AC voltage between each of the outer electrodes 17A, a terminal S between the fixed resistors R1 and Rx is applied. If the measuring circuit 44 as a signal detection and display means is constructed by measuring the change in the voltage Vss between the inner electrode 21A or 25A and the inner electrode 21A or 25A,
When a small amount of a predetermined amount of replacement fluid, e.g., electrolyte 45, is discharged from the central spout pipe 12 installed in the head board 10, the electrolyte 45 flows into the observation section 11 along with groundwater.
During this time, the resistance RXzt between the one outer electrode 13A and the inner electrode 21A
Alternatively, since the resistance value of the resistor RXti between the other inner electrode 25A and the outer electrode 17A changes sequentially, this resistance change can be understood as a change in the measurement voltage v1m described above. The other electrodes on the same line, such as the outer electrode 14A, the inner electrodes 22 and 26, and the outer electrode 18A, are configured in the same way, and voltage changes are individually measured in each bridge circuit. .

Next, 1. The overall operation of the above embodiment will be explained.〇 First, the probe 4 is lowered inside the Darling hole l while being oriented in a predetermined direction by the compass 5, and when it reaches near the bottom wall IB of the hole, the first hose 6, the aqua regia is sent out from the outside through the water supply distributor 29 and each outlet pipe 3G, 31. −
..., pressurized water is ejected (injected) toward the hole bottom wall IBK below from the tip of the spout pipe 12 and each of the electrode rods 13 to 28 (see FIG. 9). When the probe 4 is lowered further while the aqua regia is being fed, a part of the bottom wall IB of the hole is damaged by the jet flow from each spout pipe 12 and the electrode rods 13 to 28, as shown in Fig. 1O. is dug down and the flow becomes soft, so the spout pipe 12 and the electrode rods 13 to 28 are gradually inserted into the hole bottom wall IB. Then, when the delivery of aqua regia is stopped at a predetermined timing, the pouring pipe 12. When the area around the electrode rods 13 to 28 is backfilled and the probe 4 is further vibrated vertically or suppressed downward, the lower end of the probe 4, including the inside and outside of the observation section 11, is finally buried in the groundwater aquifer. (See Figure 11). Therefore, the observation unit 11 is integrated with the groundwater aquifer and has substantially the same soil properties, thereby providing almost the same flow of groundwater as the groundwater in the groundwater aquifer.

Next, after the disturbance of groundwater etc. caused by lowering the globe 4 and the burying work has subsided, a predetermined amount of electrolyte as a replacement fluid is injected from the outside via the second hose 7 as shown in Fig. 12 (4).
The water slowly pours out into the groundwater layer within the observation section 11. At this time, due to the soil properties (frictional resistance to fluid) K of the groundwater layer, the electrolyte is discharged very quietly, suppressing the occurrence of turbulence, and therefore, without disturbing the flow of groundwater in the groundwater layer. The desired electrolyte mass 45 is formed. Here, to explain the case where the groundwater W flows, for example, in the direction from the external electrode rod 13 to the external electrode rod 17, the electrolyte mass 45 also moves as the groundwater flows, and the time When T1 has elapsed and the front edge of the electrolyte mass 45 reaches the inner electrode 25A (see FIG. 12 (b)), the resistances RXts of the inner and outer electrodes 25A and 17 begin to change, and the voltage v It starts to rise (see Tl in Figure 13). As a result, groundwater W
It is detected that the flow direction is from the external electrodes 13A to 17A. This direction is 5 so that it can be accurately specified based on the above-mentioned compass needle 5. Subsequently, a period of time T has elapsed, and the electrolytic mass 4S is connected to the inner electrode 25A and the outer electrode 17.
When transferred between people (see FIG. 12, 0), the voltage vtI shows a peak. In this case, when the width of the electrolyte mass 45 is relatively large, the peak value of the voltage VB continues until the left edge of the scissors electrolyte mass 45 reaches the inner electrode 25A, that is, until the time Ts reaches Ts. (See FIG. 13) 0 Therefore, the electrolyte mass 45 is connected to the other inner electrode 25.
Calculating the time (Tx-TI) from when it reaches the person until it advances further and reaches the outer electrode 17A, the electrode 25A
, 17 The groundwater flow velocity can be easily determined by calculating L/(Tt-Tt), where L is the distance between people.

On the other hand, in other measurement electrode groups, for example, the outer electrode 20
A, Inner electrode 28m, 24 people, Outer electrode 16A, voltage 7 related to the bridge circuit, Inner electrode 24AK Electrolyte mass 4
5 arrives later than the timing at which the inner electrode 25AK arrives, and also passes past the electrodes 24A and 16, the voltage ■! 4 is delayed and the peak value is also low (v! in Figure 12).
(see 4).

Next, when the electrolytic solution 45 flows away together with the groundwater and the voltage ts etc. shows a zero value, the electrolytic solution is sent out again through the second hose 7 and observed. By forming the electrolyte mass 45 in the portion 11, the second flow measurement can be started. Such operations can be performed any number of times under the same conditions.

For this reason, in this first embodiment, even if the groundwater layer is a sandy layer, a relatively small amount of aqua regia can be spouted from the tip of each electrode rod, etc., to easily and reliably secure the observation area. can be buried in the groundwater aquifer to be measured. Therefore, by simply pouring a small amount of electrolyte into the center of the observation section, it is possible to measure the flow of groundwater in the actual groundwater aquifer. Since measurements can be made extremely accurately and measurements can be repeated many times under the same conditions, measurement accuracy can be improved and measurement work can be made simpler and faster.

In the above embodiment, the case where the vicinity of the observation section is buried in the ground is exemplified, but the entire probe may be buried to further improve the measurement accuracy as shown in FIG. 6'. In addition, the injection of pressurized water may be carried out by incorporating an injection pump into the probe body and circulating the water in the polling hole.Furthermore, the injection of the electrolyte may be carried out by incorporating a piston means into the globe body. It's okay. In addition, as a replacement fluid, not only electrolytes but also insulating oil with a high dielectric constant may be used to take advantage of the difference in capacitance with groundwater, or liquids with different pH values (acid or alkaline solutions) may be used. The displacement with the groundwater may be detected using an electrode for measuring PH,
Furthermore, measurement sensitivity may be improved by using a composite material mixed with metal particles, etc. In short, the electrical (resistivity, permittivity, etc.) or chemical (PI (etc.) Any liquid substance (including a sol-like substance) with different specific gravity and viscosity, electrodes and measurement circuits corresponding to the substance with different density and viscosity may be used.In addition, as the displacement fluid mass, in the groundwater to be measured, It may be one in which an ion layer is formed by electric discharge, etc. Also, the measurement electrode rod may be arranged not only radially but also in a mesh pattern, etc. Also, a shield electrode having an aqua regia spout around the measurement electrode rod may be used. A rod may be arranged to eliminate external noise such as mine flow.Furthermore, the hole wall may be collapsed by blowing out gas such as air, and one hole bottom wall may be collapsed. If the probe is soft, or if sand or the like has been added, the observation section can be buried more easily than by simply pressing down the probe without ejecting aqua regia.

Next, a second embodiment will be described based on FIGS. 14 to 19.

This second embodiment is similar to the electrode 1 in the first embodiment described above.
Among 3 to 28 people, the inner electrodes 21A to 28A are connected to the annular electrode 50. 13 to 20A outer electrodes, 51 to 5 independent electrodes each
8, and each of the annular electrodes 50 and independent electrodes 51 to 58 are formed in 5 so as to be flush with the lower end surface of the head board 10A (see FIG. 14), and these independent electrodes 51 to 58 and the annular The electrodes located on the same straight line, including the electrode 5G, are configured to be handled as a group of measurement electrodes, and the measurement circuit 59#c as the signal detection and display means is, for example, as shown in FIG. It is composed of In this FIG. 16, RXII is an independent electrode 5
0 represents the electrical resistance between the independent electrode 55 and the annular electrode 50, and RXIi represents the electrical resistance between the independent electrode 55 and the annular electrode 50.
The other analog switches 60.
1, RXII and RXss, RXiz and R
Xss.

・By sequentially switching and connecting -, each measurement electrode group k
A K-order bridge circuit is constructed, and the measured voltage V is displayed on a multi-channel recorder or the like in the same manner as in the first embodiment described above.

Further, the spout pipe 12 in the first embodiment is replaced with the head plate 10.
It is carved near the outer periphery of the lower end surface of A, and there is a porous member 62 inside.
A ring-shaped spout groove 63 is fitted with a distributor 64 and a check valve 65 at the tip of the second hose 7 for supplying the replacement liquid.
．． 65 are connected to each other, and the pipes 6g, 66°, . . . are opened into the pouring groove 63. Therefore, when the replacement liquid is introduced via the second hose 7 from the outside, the dispensing @ 6
The replacement liquid poured out from 3 forms a doughnut-shaped replacement mass. On the other hand, the spout pipe 12 in the first embodiment
．． In this second embodiment, the ejection parts provided on the electrode rods 13 to 27 are integrated into a lead-out pipe 67 that opens at the lower end surface of the head panel 10A, and serves as a first hose for supplying pressurized water. In the second embodiment configured in this manner, the four probes are lowered while spouting aqua regia from the outlet pipe 67, as shown in FIG. And, due to the jet flow, the hole bottom l1IB
will collapse and weaken as a whole, so if you stop the ejection at a predetermined timing and push down the four probes, you can easily move the observation section 11A on the lower side of the head panel 10A into the groundwater layer as shown in Figure 18. It can be in a buried state. See you again
After layering S11A, for example, an electrolytic solution is poured out as a replacement liquid as shown in FIG. It moves near the lower side of the annular electrode 50. At this point, the electric field generated between each electrode extends into the groundwater layer, so that the change in resistance caused by the movement of the electrolyte mass 45 is detected by each electrode, and the electrolyte mass 45A is donut-shaped. Therefore, since it always crosses under one of the electrode groups and moves as shown in FIG. 19@0, groundwater flow can be reliably measured in the same manner as in the first embodiment.

Therefore, even with this configuration, the same effects as those of the first embodiment described above can be achieved, and there are advantages in that the configuration can be simplified and durability can be increased.

In addition, in this second embodiment, the independent electrodes 51 to 58 may be arranged inside the annular electrode 50.

In addition, if the bottom wall of the hole has been weakened or soft ground or sand has been poured into the hole when drilling a poling hole, it is possible to simply press down on the globe without squirting out aqua regia. .

Next, a third embodiment will be explained based on FIGS. 20 to 22.

In this third embodiment, the ejection part in the first embodiment described above is provided on the side of the probe.

To explain this more specifically, from the water supply distributor 29B connected to the first hose 6, check valves 70° 70, -.
- Outlet pipe 71.71. ...The glove body 9
It is arranged horizontally up to the side wall of the isthmus probe body 9B, and has an open end on the outside of the isthmus probe main body 9B. Head board 10
In B, electrode wires 72 to 87 are implanted in place of the electrode rods 13 to 28 of the first embodiment, and a spout pipe 12 is installed in the center.
B is provided protrudingly. This spouting pipe 12B is connected to the second hose 7 via a check valve 88, and the tip IC%
The replacement liquid can be poured out from the inserted porous member 89. The replacement liquid poured out from the pouring pipe 12B is caused by the electrode wire groups 72 to 87, in exactly the same way as in the first embodiment. In this third embodiment, the probe 4B is lowered and installed near the hole bottom wall IB as shown in Figure 22. , outlet pipe 7
When pressurized water is ejected from 1, 71, --..., the hole side wall 1
The person is disintegrated as shown in ) in the same figure, and therefore probe 4B's [
The surroundings of the electrode lines 72 to 87 provided in 1K, that is, the observation section 11B will be gradually backfilled (22nd
(See Figure 0). Therefore, in addition to producing the same effect as the first embodiment described above, the observation unit 11
Since the probe 4B can be buried, it is possible to reliably set the orientation of the probe 4B in a predetermined direction, and the burying work is also facilitated. In addition, since excessive force is not applied to the electrode wires 72 to 87 and the head board 10BI'C, there is no need to strengthen the globe 4.
It won't hurt B. Furthermore, since the observation part and the spouting part are separated, pressure water will not penetrate into the observation part and disturb the measurement.In addition, in this third embodiment, each measurement electrode and spout pipe are As in the second embodiment (head board 1
It may be formed flush with the 0B surface. In addition, as shown in Figure 23, the jetting of pressurized water has a double pipe structure around the probe body, with 90 discharge ports on the side.

90A, . . . may be configured to communicate with the boring rod 3 and send pressurized water through the boring rod 3. According to the example shown in FIG. 23, the outer tube section 90 can perform the protective function of the probe main body section 91.

Furthermore, as shown in FIG.
9C and an outlet pipe 92.92.92.92.92.92.92.92.92.92.
... may be detachably installed on the outer periphery of the probe body.

Next, a fourth embodiment will be described based on FIGS. 25 to 29.

In this fourth embodiment, in the third embodiment described above, the replacement liquid is also used as the jetting liquid for burying, and the entire globe is completely backfilled in the ground, and the total time is 5K. That is, a connecting tube section 100 is provided at the lower end of the boring rod 3 and is detachably screwed onto the #l-ring rod 3, and the probe 4D is attached to the lower side of this connecting tube section 1000.

This probe 4D is on the outer periphery of the probe body 9D.

Four fins 101.101. in the vertical direction. -... are attached, and these fins 101, 101. -...By loosening the part, the probe 4Dt can be fixed in a non-rotatable manner. On the other hand, inside the probe body 9D, a cable 8 and a pressure-resistant hose 6D are connected to the connecting pipe portion 1 from the outside.
00 and rubber members are extended through the densely-contained atoz and tos. This pressure-resistant hose 6D is connected to a distributor 105 via a solenoid valve 104, and this distributor 105 is further connected to outlet pipes 106, 106, 106, 106, 106, 106, 106, 106, 106, 106, 106, 106, 106, 100, 100, 100, 100, etc. - indicates the side wall and fins 101.101. of the probe body 9D. The fins 101.101. -... is opened at the tip surface. Further, the spout pipe 12D formed in the same manner as in the third embodiment is connected to the pressure hose 6D via the solenoid valve 104, and other components are formed exactly the same as in the third embodiment. In the probe 4DK configured in this manner, a replacement liquid having electrical and chemical properties different from groundwater is fed into the pressure hose 6D.
When burying the observation section 11DIL of D, after switching the solenoid valve 104 to the distributor 105 side by external operation,
A high-pressure replacement liquid is fed through the pressure hose 6D. Then, the replacement liquid is spouted sideways from the tip of the outlet pipe 106, 106, -, and the hole side wall 1 is ejected in exactly the same manner as in the third embodiment.
The person is destroyed, and the observation section 11D is buried as shown in FIG. The replacement liquid 45D spouted at this time is
As shown in Figure 8, it spreads to the periphery of the 5#c observation section, and therefore, as the groundwater flows, the cough replacement mass 45D moves as shown in Figure IXQx, so it is almost the same as the first embodiment described above. groundwater flow can be measured using In addition, by pouring out the replacement liquid again from the outlet pipes 106, 106, ..., it becomes possible to carry out repeated measurements. First, after burying the observation part in the same manner as described above, the outer peripheral part of the probe 4D is returned to 5 pieces as shown in Figure 29.The globe 4D is Since it is fixed, here the above is -
After the ring rod 3 can be removed and #ll-ring rod 3 is removed (see figure (b)), the inside of the polling hole l is further backfilled to near the ground surface (the casing 2 is refilled as necessary). At this time, the lid 7 in the first half-portion tube part z is arranged to receive pressure after backfilling.

Next, after switching the electromagnetic valve 104 to the spouting pipe 12D side, if the replacement liquid is pumped through the pressure hose 6D, the replacement liquid will be spouted into the observation section from the spouting pipe 12D. As shown in FIG. 29(b)k, a desired replacement mass 45B can be repeatedly formed.

According to the fourth embodiment, the replacement liquid can also be used as the ejecting liquid for installation, which has the same effect as the third embodiment, so the configuration is simplified and the globe 4D
Since it can be completely buried in the ground, there is no intrusion of rainwater, etc., which improves measurement accuracy and enables stable measurement over a long period of time.

In each of the above embodiments, the collapse of the hole wall is performed by jetting liquid, but the present invention is not limited to this in any way, and the collapse of the hole wall is performed by poling. The water in the hole may be jetted and stirred. Specifically, as shown in the 30th [K, rotary blades 110, 110 . - by rotating or reciprocating with a motor or the like (not shown), the water in the hole is jetted or stirred, and the impact of the water in the hole hitting the wall of the hole is used to cause the wall of the hole to collapse. This is effective when the hole wall is relatively soft.Also, the electrode rod installed in the probe is formed into a nail shape with a large diameter, strong rigid member, etc. The electrode rod may be moved up and down or rotated to repeatedly collide with the hole wall to cause the bottom wall of the hole to collapse and weaken, and the observation unit may be installed by inserting the electrode into this collapsed ground. Often, one probe is formed to have a relatively thick wall 11, and a small explosive or a submerged discharge part is provided on the outer periphery of the probe, and the impact pressure from the explosion or discharge is used to cause the hole wall to collapse, thereby forming an observation part. You may also install the following.

As described above, according to the present invention, the observation section for measuring the flow of groundwater is installed directly within the groundwater aquifer, and by moving the displacement fluid mass to the observation section, the flow of groundwater can be easily and extremely accurately measured. It is possible to provide an excellent groundwater flow measurement method that can be used to measure groundwater flow.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the usage state of an embodiment according to the present invention,
Fig. 2 is a vertical cross-sectional view showing the first embodiment, Fig. 3 is a plan view of Fig. 2, Fig. 4 is a partially omitted cross-sectional view showing the electrode rod part of Fig. 2, and Fig. 5 is a cross-sectional view of the first embodiment. FIG. 4 is a plan view, FIG. 6 is a partially omitted partial sectional view showing the spouting pipe portion in FIG. 2, FIG. 7 is a plan view of FIG. 6, and FIG. 8 is an example of the signal detection and display means. 9 to 11, FIG. 12＠0 and FIG. 13 are respectively explanatory diagrams of the operation of FIG. 2, FIG. 14 is a partial sectional view showing the second embodiment, and FIG. 15 is a plan view of FIG. 14, FIG. 16 is a circuit diagram as a signal detection and display means according to the second embodiment, FIGS. is a partial sectional view showing the third embodiment,
21 is a plan view of FIG. 20, FIG. 22 N(C)0 is an explanatory diagram of the operation of FIG. 20, FIG. 23 is a partially cutaway external view showing a modification of FIG. 20, and FIG. The figure is an outline drawing showing another modification of Fig. 20, Fig. 25 is a partial sectional view showing the fourth embodiment, Fig. 26 is a plan view of Fig. 25, and Figs. 27 and 28 (to). 03) (Q is the action explanatory diagram in Fig. 25,
- FIGS. 29(6) and 29(b) are other explanatory diagrams of the operation of FIG. 25, and FIG. 30 is a schematic diagram showing another embodiment. 1... Seeling hole, IA... hole side wall, IB hole bottom wall, 11.11A, 11B, 11D-observation section, 13-2
7... Electrode rod, 50... Annular electrode, 51-58...
・Independent electrode, 72-87...electrode wire, 29.29B,
29C,--Water supply distributor, 3G, 31. −・・ , 6
7.71.92.106゜・・・Outlet pipe, 45.45A
, 45D, 45E... replacement mass, 110... rotary blade. Patent applicant: Taisei Basic Design Co., Ltd. Figure 2 Figure 3 Figure 4 Figure 5 Figure 5 4Q 4UA Figure 6 Figure 7 Go to Figure 14\ 57 56 Figure 16 9 Figure 23 Figure 24 Figure 25 l1l ) Fig. 26 Fig. 27 (8)

Claims (1)

[Claims] (1) An observation section equipped with a plurality of measurement electrodes is provided, and this observation section is lowered into a predetermined groundwater layer of a poling hole drilled in the ground, and while the observation section is lowered, Or before and after descent, the test subject l! l! A part of the hole wall near the hole collapsed into mud and the observation part was buried in the ground, and then
A displacement fluid mass having electrical or chemical properties different from that of groundwater is caused to flow within the observation section according to the flow of groundwater, and changes in electrical or chemical properties caused by this flow are detected and calculated by the observation electrode. A groundwater flow measurement method featuring: (:2) A groundwater flow measuring method described in a patent, characterized in that the collapse of the hole wall is carried out by causing fluid to flow against the hole wall by stirring, jetting, jetting, etc. C3) The underground water flow measuring method according to claim 1, wherein the collapse of the hole wall is performed by driving a nail-like member into the hole wall. (4) The underground water flow measuring method according to claim 1, characterized in that the collapse of the hole wall is performed by applying impact pressure such as explosion or electric discharge to a part of the hole wall near the depth to be tested. .