JP2003268759A - Underground water pumping method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively collect and pump water by previously refining underground water so that the underground water smoothly and easily flows toward the water feeding part side in the surrounding ground of a casing pipe before pumping the underground water collected in the casing pipe buried in the ground. <P>SOLUTION: A ground refining process is performed for refining the surrounding ground 1 so as to form a cleaved water feeding passage by cleaving the surrounding ground 1 under the casing pipe 3 by pressurized water by forcibly sending the pressurized water in the ground 1 from a water feeding part 2 arranged in a lower end part of the casing pipe 3 before pumping the flowed-in underground water by a pumping means 4 by making the underground water flow in from the water feeding part 2 arranged in the lower end part of the casing pipe 3 buried in the ground 1. After performing this ground refining process, a regular pumping process is performed for pumping the underground water by making the underground water flow in the casing pipe 3 from the water feeding part 2 via the cleaved water feeding passage formed in the surrounding ground 1 by the pumping means 4. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for pumping groundwater in order to lower the groundwater level when excavating the ground for underground construction or when improving the ground.

[0002]

2. Description of the Related Art Conventionally, groundwater has been pumped to lower the groundwater level when excavating the ground for underground work or improving the ground. By pumping groundwater and lowering the groundwater level in this way, the water content of the target soil is lowered, and excavation work and treatment of excavated soil can be performed easily.

In pumping groundwater, groundwater is introduced from a water passage provided at the lower end of a casing pipe buried in the ground, and the inflowing groundwater is pumped by a pumping means. Is, for example, the deep well method of draining by utilizing the water head difference between the natural water level and the water level in the well, or by providing a pressure reducing means in the deep well device to reduce the pressure in the well to further reduce the groundwater level. The vacuum deep well method is known. Further, as another conventional example, Japanese Patent Laid-Open No. 2000-27
170 are known. This Japanese Patent Laid-Open No. 2000-2717
0 is equipped with a strainer device at the lower end of the casing pipe,
Groundwater is collected into the casing pipe through the strainer device by the vacuum force generated by decompressing the casing pipe with the water head difference and decompression means, and the groundwater thus collected in the casing pipe through the strainer device is collected by the pump. I try to pump up.

However, in any of the above-mentioned conventional examples, the casing pipe is simply buried in the ground and the groundwater is pumped by each of the above-mentioned methods. However, when the casing pipe is buried in the ground, The water passage provided at the lower end of the pipe does not always match the portion of the ground where water exists, but rather the water passage at the lower end of the casing pipe and the portion of the ground where water exists. In many cases, the geology around the water passage portion of the casing pipe is difficult to pass water. Therefore, when groundwater is collected into the casing pipe from the water passage part at the lower end of the casing pipe by each of the above methods (due to the water head difference or the water head difference and the vacuum force), the ground water surrounds the lower part of the casing pipe. There was a problem that the water collection effect was poor because it was difficult for water to pass through to the water flow side of the ground.

[0005]

The present invention has been made in view of the above points, and prior to pumping groundwater collected in a casing pipe buried in the ground, the ground pipe around the casing pipe is passed through in advance. An object of the present invention is to provide a groundwater pumping method capable of effectively collecting and pumping water by reforming the groundwater so that the groundwater can smoothly flow toward the water side.

[0006]

[MEANS FOR SOLVING THE PROBLEMS] In order to solve the above-mentioned problems, a groundwater pumping method according to the present invention allows groundwater to flow in from a water passage 2 provided at a lower end of a casing pipe 3 buried in a ground 1. Prior to pumping the groundwater by the pumping means 4, pressurized water is pumped into the ground 1 from the water passage 2 provided at the lower end of the casing pipe 3 to split the ground 1 around the lower part of the casing pipe 3 with the pressurized water. After performing the ground reforming process for reforming the surrounding ground 1 so as to form a split water passage, the split water passage formed in the surrounding ground 1 by the pumping means 4 is performed. The present invention is characterized in that a main pumping step is carried out in which ground water is caused to flow into the casing pipe 3 from the water passing portion 2 through the pump to pump water. By adopting such a method, before carrying out the main pumping, the surrounding ground 1 is reformed in advance so as to form a split water passage in the surrounding ground 1 at the lower part of the casing pipe 3. Effectively collecting groundwater in the casing pipe 3 by reforming the ground 1 around the lower part of the casing pipe 3 and then performing main pumping to pump groundwater collected in the casing pipe 3 by the pumping means 4. It can be watered and pumped efficiently.

Further, the ground 1 around the lower part of the casing pipe 3
In reforming the surrounding ground 1 so as to split the water with pressurized water to form a split water passage, it is preferable to continuously feed the pressurized water to the ground 1 around the lower portion of the casing pipe 3. By adopting such a method, before carrying out the main pumping, in order to reform the surrounding ground 1 in advance so as to form a split water passage in the surrounding ground 1 under the casing pipe 3, pressurized water is supplied. By continuously pumping to the ground 1 around the lower part of the casing pipe 3, a split water passage can be easily formed around the lower part of the casing pipe 3 to improve the ground.

Further, the ground 1 around the lower part of the casing pipe 3
In reforming the surrounding ground 1 so as to split the water with pressurized water to form a split water passage, the pressurized water is fed to the ground 1 and the groundwater of the ground 1 saturated by the pressurized water is fed to the ground 1. It is preferable that the ground 1 be reformed by alternately repeating suctioning of water by vacuum and pumping water by the pumping means 4. By adopting such a method, before carrying out the main pumping, in order to reform the surrounding ground 1 in advance so as to form a split water passage in the surrounding ground 1 under the casing pipe 3, pressurized water is supplied. By continuously pumping to the ground 1 around the lower part of the casing pipe 3, the ground 1 around the lower part of the casing pipe 3 can be easily split, and the clogging particles generated by the splitting by vacuum suction and pumping can be removed by suction. By repeating this, a split water passage can be formed to smooth the water flow, and the ground can be reformed.

Further, the ground 1 around the lower part of the casing pipe 3
In reforming the surrounding ground 1 so as to form a split water passage by splitting with water under pressure, a pumping pump 8 is provided at the lower end of a pumping pipe 7 having an opening / closing valve 6 to form a pumping means 4. The pumping pipe 7 is inserted into the casing pipe 3 whose upper end is closed to dispose the pumping pump 8 in the lower part of the casing pipe 3, and the vacuum pump 9 is provided at the upper end of the casing pipe 3.
Water pipe 1 having a water supply valve 13 connected to a vacuum pipe 11 having an air valve 10 connected to the casing and a water supply pump 12 for supplying pressurized water into the casing pipe 3.
4 is connected, the water supply valve 13 is opened in a state where the on-off valve 6 and the air valve 10 are closed, and pressurized water is pressure-fed into the casing pipe 3 buried in the ground 1 by the water feed pump 12 so that the water passage portion 2 A pressurized water pumping step of pumping pressurized water into the ground 1 to split the ground 1 around the lower part of the casing pipe 3 with the pressurized water, and then stopping the operation of the water pump 12 to close and open / close the water valve 13. Pumping pump 8 and vacuum pump 9 are operated with valve 6 and air valve 10 open to pump water while suctioning clogging particles in ground 1 into casing pipe 3 together with groundwater in ground 1 by vacuum suction. It is also preferable that the washing pumping step of pumping water by the pump 8 is carried out, and the pressurized water pressure feeding step and the washing pumping step are alternately repeated. By adopting such a method, it is only necessary to operate the opening / closing valve 6 and the pump 8, the air valve 10 and the vacuum pump 9, and the water pump 12 and the water valve 13 to open / close and operate / stop. 1 and the ground water of the ground 1 which has been saturated due to the pressurized water being pumped to the ground 1 can be alternately sucked and pumped by the pumping means 4 to repeatedly reform the ground 1. It is a thing.

Further, the ground 1 around the lower part of the casing pipe 3
In reforming the surrounding ground 1 so as to form a split water passage by splitting with water under pressure, a pumping pump 8 is provided at the lower end of a pumping pipe 7 having an opening / closing valve 6 to form a pumping means 4. The pumping pipe 7 is inserted into the casing pipe 3 whose upper end is closed, the pumping pump 8 is arranged in the lower portion of the casing pipe 3, and the air vent 16 having the air vent valve 5 is connected to the upper end of the casing pipe 3. In addition, a water supply pipe 14 having a water supply valve 13 connected to a water supply pump 12 for supplying pressurized water into the casing pipe 3 is connected, the open / close valve 6 is closed, and the air bleeding valve 5 is opened. Is opened and pressurized water is pumped into the casing pipe 3 by the water pump 12 to fill the casing pipe 3 buried in the ground 1 with pressurized water, and the air bleeding valve 5 is closed. The pressurized water is pumped into the ground 1 by pumping the pressurized water into the ground 1, and the pressurized water pressure feeding step of splitting the ground 1 around the lower part of the casing pipe 3 with the pressurized water is performed. When the operation is stopped to close the water supply valve 13 and the air bleeding valve 5 is closed, the opening / closing valve 6 is opened to operate the water pump 8 to pump the water in the casing pipe 3 to vacuum the casing pipe 3. A washing pumping step is performed in which a space is formed and the clogging particles in the ground 1 as well as the groundwater in the ground 1 are sucked into the casing tube 3 by suction due to the vacuum generated in the casing tube 3 by the pumping pump 8. It is also preferable that the method is performed and the pressurized water pressure feeding step and the washing pumping step are alternately repeated. On-off valve 6, pumping pump 8, air vent valve 5,
By simply opening / closing and operating / stopping the water feed pump 12 and the water feed valve 13, the pressurized water is pumped to the ground 1 and the groundwater of the ground 1 saturated by the pressurized water is pumped to the ground 1. The ground 1 can be reformed by alternately repeating suction and pumping by the pumping means 4, and in particular, the upper part of the casing pipe 3 is evacuated by a simple method without using a vacuum pump. As a result, ground water and clogging particles can be sucked into the casing pipe 3 by vacuum suction.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on the embodiments shown in the accompanying drawings.

In the present invention, when excavating the ground for underground construction or pumping the groundwater of the corresponding ground 1 for improving the ground, first, the casing pipe 3 is placed on the ground 1.
Next, the pressurized water is pumped into the ground 1 from the water passage 2 provided at the lower end of the casing pipe 3, and the ground 1 around the lower part of the casing pipe 3 is split by the pressurized water to form a split water passage. The ground reforming step of reforming the surrounding ground 1 is performed as described above. In this way, the ground 1 around the casing pipe 3 is reformed so that ground water can smoothly flow through the ground around the lower part of the casing pipe 3 to collect water from the water passage 2 into the casing pipe 3. After performing this ground reforming process, a main pumping process is carried out in which groundwater is pumped into the casing pipe 3 from the water passage part 2 through the split water passage formed in the surrounding ground 1 by the pumping means 4. To do.

1 to 4 show an embodiment of the present invention. The casing pipe 3 embedded in the ground 1 is made of a steel pipe, and a strainer portion 21 is provided on the lower end of the casing pipe 3 on the outer periphery of the lower tubular portion 3a so as to surround the lower tubular portion 3a via a gap 20 in the vertical direction. A sand pool 22 is provided at the lower end of the lower tubular portion 3a. The lower tube portion 3a is provided with the water passage portion 2. Further, the strainer portion 21 is made of, for example, a steel wire wound around the outer periphery of the frame body so as to form gaps at predetermined intervals and has a substantially cylindrical shape, and a large number of gaps formed in the vertical direction serve as the water passage portion 23. Groundwater can be made to flow in. The strainer portion 21 is not limited to the one configured by winding the steel wire as described above, and may be configured by a perforated cylinder having a large number of holes to serve as the water passage portion 23. In any case, the uppermost water passage portion 23 of the strainer portion 21 is located above the water passage portion 2.

A lid 24 is attached to the upper end of the casing tube 3 to close the upper opening of the casing tube 3. Also,
A pumping pump 8 is provided at the lower end of a pumping pipe 7 having an opening / closing valve 6 to form a pumping means 4, and the pumping pipe 7 is inserted into a casing pipe 3 whose upper end is closed to connect the pumping pump 8 to the casing pipe 3. It is located at the bottom of the inside. In the embodiment shown in the accompanying drawings, the pumping pipe 7 is attached by inserting the lid 24 therethrough. A vacuum pipe 11 having an air valve 10 connected to a vacuum pump 9 at the upper end of the casing pipe 3
And a water supply pipe 14 having a water supply valve 13 connected to a water supply pump 12 for supplying pressurized water into the casing pipe 3. In the embodiment shown in the accompanying drawings, the ends of the vacuum pipe 11 and the water supply pipe 14 are attached to the lid 24, and the ends of the vacuum pipe 11 and the water supply pipe 14 are opened in the casing pipe 3. Here, the opening position of the end of the water supply pipe 14 in the casing pipe 3 is the vacuum pipe 1
1 is located below the opening position in the casing pipe 3.

When burying the casing pipe 3 of the groundwater pumping apparatus having the above-described structure in the ground 1, a hole 25 having a diameter larger than that of the casing pipe 3 is drilled in the ground 1 from which groundwater is to be pumped. The casing pipe 3 of the groundwater pumping device is inserted into the hole 25.
The filter material 26 such as coarse sand or gravel is filled between the inner wall of the casing pipe 3 and the outer peripheral surface of the casing pipe 3, and cement mortar or bentonite is further provided between the upper portion of the inner wall of the perforation 25 and the upper portion of the outer peripheral surface of the casing pipe 3. A sealing material 27 such as mortar is filled and sealed. Here, in sealing between the upper part of the inner wall of the perforation 25 and the upper part of the outer peripheral surface of the outer tube 3, a balloon between the upper part of the inner wall of the perforation 25 and the upper part of the outer peripheral surface of the casing tube 3 is inserted. The balloon may be sealed by other means such as inflating the balloon.

As described above, the casing pipe 3 of the groundwater pumping device is buried in the ground 1, and the groundwater in the ground 1 is pumped up by means 4
In the present invention, prior to the main pumping by the pumping means 4, the ground 1 around the lower part of the casing pipe 3 is first ground-reformed to facilitate the passage of groundwater.

In carrying out ground improvement, first, referring to FIG.
As shown in, the water supply valve 13 is opened with the on-off valve 6 and the air valve 10 closed, and the water in the water storage tank 28 is pumped by the water supply pump 12 into the casing pipe 3 buried in the ground 1, Pressurized water is pumped into the ground 1 from the water passage 2 at the lower end of the casing pipe 3 through the water passage 23. In this way, by forcibly feeding the pressurized water into the ground 1 around the casing pipe 3, the pressurized water pressure feeding step of splitting the ground 1 around the lower part of the casing pipe 3 with the pressurized water is performed. In this case, since the sealing material 27 is used for sealing, the pressurized water does not rise along the outer surface of the casing pipe 3 and jet to the ground.

Next, as shown in FIG. 2, the water pump 12
Operation is stopped to close the water supply valve 13 and the open / close valve 6 and the air valve 10 are opened, and the pumping pump 8 and the vacuum pump 9 are operated to become saturated by the pressurized water pressure feeding process by vacuum suction. The groundwater in the ground 1 is sucked at once, and the clogging particles in the ground 1 generated by the splitting together with the groundwater in the ground 1 are sucked into the casing pipe 3 via the water passage portion 23 and the water passage portion 2 by the pumping pump 8. A washing pumping process for pumping is carried out. In this case, the sealing material 2
Since it is sealed by 7, air on the ground is not sucked along the outer surface of the casing tube 3.

When the ground water in the ground 1 which has been saturated by the pressure-feeding of the pressurized water in this manner is pumped, the pressurized-water pressure feeding step and the washing pumping step are alternately performed in the same manner.

Here, a large number of split water passages are formed around the lower portion of the casing pipe 3 by the pressure feed of the pressurized water to the ground 1, and clogging particles generated when the split water passages are formed by the pressure feed of the pressurized water are removed. By alternately forming forcible suction and pumping by vacuum suction, the split water channel that becomes a "water channel" gradually grows so that groundwater can easily flow smoothly, and clogging particles are removed. This will make it easier for groundwater to flow smoothly.

After the ground reforming process for reforming the ground 1 around the lower part of the casing pipe 3 to facilitate smooth passage of groundwater as described above, the pumping means 4 is then used to pump the surrounding ground. The main pumping step is carried out in which groundwater is caused to flow into the casing pipe 3 from the water passage portion 2 through the split water passage formed in 1.

The main pumping process is performed as follows. That is, as shown in FIG. 3, the water supply pump 12 is stopped and the water supply valve 13 is closed.
0 is opened, the pumping pump 8 and the vacuum pump 9 are operated, and the ground water of the ground 1 is provided in large numbers in the up and down direction by the water head difference and vacuum suction. The water is collected in the casing pipe 3 through the water passage 2 at the lower end of the casing pipe 3, and the groundwater collected in the casing pipe 3 is pumped by the pump 8. In this main pumping process, since the split water passage has already been formed in the ground 1 around the lower part of the casing pipe 3 in the preceding ground reforming process, the groundwater smoothly flows through the formed split water passage to the casing pipe 3. The water flows into the water passage 2 at the lower end of the casing, and the water is effectively collected in the casing pipe 3 by the water head difference and vacuum suction, and thus the water is effectively collected in the casing pipe 3. Therefore, pumping by the pump 8 can be efficiently performed without loss.

In the case where the strainer portion 21 is provided, even if the groundwater level is located below the upper end portion (uppermost water passage portion 23) of the strainer portion 21, the uppermost water passage portion 23 is Since it is located above the water passage portion 2, the air in the ground 1 that has entered the gap 20 from the upper end of the strainer portion 21 cannot enter the casing pipe 3 from the water passage portion 2, and Since the air gathers in the upper part of the casing 20, air is prevented from flowing into the casing pipe 3 due to a decrease in the groundwater level, so that the depressurized state in the casing pipe 3 is not broken, and the inside of the casing pipe 3 is sucked by vacuum suction. It is possible to continuously collect groundwater.

Next, another embodiment of the present invention will be described with reference to FIGS.

A lid 24 is attached to the upper end of the casing tube 3 to close the upper opening of the casing tube 3. Also,
A pumping pump 8 is provided at the lower end of a pumping pipe 7 having an opening / closing valve 6 to form a pumping means 4, and the pumping pipe 7 is inserted into a casing pipe 3 whose upper end is closed to connect the pumping pump 8 to the casing pipe 3. It is located at the bottom of the inside. In the embodiment shown in the accompanying drawings, the pumping pipe 7 is attached by inserting the lid 24 therethrough. In addition, the air vent valve 5 is provided on the upper end of the casing pipe 3.
Is connected to an air bleeding portion 16 having a water feed valve 14 connected to a water feed pump 12 for supplying pressurized water into the casing pipe 3. In the embodiment shown in the accompanying drawings, the air vent portion 1 is provided in the lid 24 portion.
6, the end of the water supply pipe 14 is attached, and the air bleeding portion 16 and the end of the water supply pipe 14 are opened in the casing pipe 3. Here, the opening position of the end portion of the water supply pipe 14 in the casing pipe 3 is located below the opening position of the air bleed portion 16 in the casing pipe 3. Also, the casing pipe 3
A water passage 2 is provided on the lower tubular portion 3a at the lower end of the. Further, in the embodiment shown in FIGS. 5 to 9, a strainer that is long in the up-down direction and surrounds the lower tubular portion 3a with a gap 20 on the outer periphery of the lower tubular portion 3a at the lower end portion of the casing pipe 3 as in the above-described embodiment. A section 21 is provided.

The casing pipe 3 of the groundwater pumping apparatus having the above structure is buried in the ground 1 in the same manner as in the above-mentioned embodiment.

Prior to the main pumping of the groundwater in the ground 1 by the pumping means 4, the ground around the lower part of the casing pipe 3 is first ground-reformed to facilitate the passage of groundwater.

In carrying out the ground improvement in this embodiment, first, as shown in FIG. 5, the water supply valve 13 is opened by opening the water supply valve 13 with the opening / closing valve 6 closed and the air bleeding valve 5 opened. Pressurized water is pumped into the casing pipe 3 by means of the pump, and when the casing pipe 3 buried in the ground 1 is filled with pressurized water as shown in FIG. 6, the air vent valve 5 is closed as shown in FIG. Pressurized water is pumped into the casing pipe 3. In this way, by forcibly feeding the pressurized water into the ground 1 around the casing pipe 3, the pressurized water pressure feeding step of splitting the ground 1 around the lower part of the casing pipe 3 with the pressurized water is performed.

Next, as shown in FIG. 8, the operation of the water supply pump 12 is stopped, the water supply valve 13 is closed and the air bleeding valve 5 is closed. In this state, the water pump 8 is operated to operate the casing pipe 3
When the water in the casing pipe 3 is pumped, the water filled in the casing pipe 3 is pumped by the pump pump 8.
A vacuum space 15 is formed in the upper part of the. Then, the clogging particles in the ground 1 are sucked into the casing pipe 3 together with the ground water saturated in the ground 1 due to the suction due to the vacuum generated in the casing pipe 3, and therefore, the pumping pump during this time. By continuing the operation of No. 6, the ground water and the clogging particles sucked into the casing pipe 3 are pumped by the pumping pump 6, whereby the casing pipe 3 remains with the vacuum space 15 formed in the upper portion. Groundwater and clogging substances will continue to be sucked in. This is the washing pumping process.

When the groundwater in the ground 1 which has been saturated by the pressurized water is pumped in this way, the pressurized water pumping step and the washing pumping step are alternately performed in the same manner. Here, in the second and subsequent pressurized water pressure feeding steps, the water feed valve 13 is opened with the on-off valve 6 closed while the air bleeding valve 5 is closed, and the casing pipe 3 is opened by the water feed pump 12.
Pressurized water is pumped inside. Then, since the casing pipe 3 buried in the ground 1 is filled with the pressurized water, the pressurized water is continuously pumped into the casing pipe 3 by the water feed pump 12, so that the pressurized water is forcibly pumped into the ground 1 around the casing pipe 3. Then, the pressurized water pressure feeding step of forming a split water passage through the ground 1 around the lower portion of the casing pipe 3 can be carried out.

In this way, a large number of split water passages are formed around the lower portion of the casing pipe 3 by the pressure feed of the pressurized water to the ground 1, and the clogging generated when the split water passages are formed by the pressure feed of the pressurized water. By alternately forming forcible suction of the particles by vacuum suction and pumping, the split water passage that becomes a "water channel" gradually grows so that groundwater can easily flow smoothly, and clogging particles are generated. Groundwater will flow more smoothly when it is removed.

When the ground reforming process for modifying the ground 1 around the lower part of the casing pipe 3 to facilitate smooth passage of groundwater as described above is completed, the pumping means 4 is then used to pump the surrounding ground. The main pumping step is carried out in which groundwater is caused to flow into the casing pipe 3 from the water passage portion 2 through the split water passage formed in 1.

The main pumping step is performed as follows. That is, the final pumping step for cleaning of the ground modification step can be continued as it is to the main pumping step as shown in FIG. 9, and the main pumping step is performed by the same action as the cleaning pumping step. Is something that can be done. In this main pumping process, since the split water passage has already been formed in the ground 1 around the lower part of the casing pipe 3 in the ground reforming process of the previous stage, the groundwater smoothly flows through the formed split water passage to the casing pipe 3 Since it flows to the water passage 2 at the lower end of the casing, water is effectively collected in the casing pipe 3 by the water head difference and vacuum suction, and thus the water is effectively collected in the casing pipe 3. Therefore, pumping by the pump 8 can be efficiently performed without loss. by the way,
In this pumping process, when the groundwater level temporarily drops and air flows into the casing pipe 3 from the water passage 2 at the lower end of the casing pipe 3, the degree of pressure reduction in the space above the casing pipe 3 decreases. Although the pumping pump 8 may be continuously operated to pump water as it is, if the degree of pressure reduction in the space above the casing pipe 3 decreases, the suction force of the groundwater into the casing pipe 3 due to vacuuming decreases. In such a case, the water supply valve 1 with the opening / closing valve 6 closed and the air bleeding valve 5 opened.
3 is opened and pressurized water is pumped into the casing pipe 3 by the water pump 12 to fill the casing pipe 3 with pressurized water.
After that, the operation of the water supply pump 12 is stopped, the water supply valve 13 is closed, the air bleeding valve 5 is closed, and the pumping pump 8 is operated in this state to pump the water in the casing pipe 3, Since the water filled in the pump is pumped by the pump 8, the vacuum space 15 can be formed in the upper part of the casing pipe 3. Therefore, by continuously operating the pump 8 in this state, the ground water is casing. The water can be pumped into the pipe 3 while vacuum suction.

In this embodiment, the upper part of the casing pipe 3 can be evacuated by a simple method without using a vacuum pump, and ground water and clogging particles can be sucked into the casing pipe 3 by vacuum suction. It is a thing.

Further, in each of the above-described embodiments, the ground 1 around the lower portion of the casing pipe 3 is split with the pressurized water to reform the surrounding ground 1 so as to form the split water passages. An example in which the ground 1 is reformed by alternately repeating suctioning of the groundwater of the ground 1 saturated by pumping of pressurized water to the ground 1 and pumping by the pumping means 4 I showed you
In reforming the surrounding ground 1 so as to form a split water passage by splitting the ground 1 around the lower part of the casing pipe 3 with pressurized water, the pressurized water is continuously pumped to the ground 1 around the lower part of the casing pipe 3. It is also possible to form a split water passage that becomes a "water channel" in the ground 1 around the lower portion of the casing pipe 3 only by doing so. For example, in the present embodiment, as shown in FIG. 1, the water supply valve 13 is opened with the on-off valve 6 and the air valve 10 closed, and the water pump 12 pumps pressurized water into the casing pipe 3 buried in the ground 1. Then, the pressurized water is pumped into the ground 1 from the water passage 2 at the lower end of the casing pipe 3 through the water passage 23. By continuously executing only this pressurized water pressure feeding step, the ground 1 around the lower portion of the casing pipe 3 is
Is split by pressurized water to gradually grow the split water passage to form a split water passage that serves as a "water channel" through which groundwater flows smoothly.

As described above, the ground water can be reformed simply by forming the split water passage around the lower portion of the casing pipe 3 only by the pressurized water feeding process.

After the ground reforming around the lower part of the casing pipe 3 is carried out in this way, the main pumping is carried out by the pumping means in the same manner as described above.

In any of the above-mentioned embodiments, the ground reforming step and the subsequent main pumping step are performed by the same groundwater pumping apparatus, so that the ground reforming and pumping can be easily performed by the common apparatus. That is, it is advantageous in terms of cost, and the construction period can be shortened.

[0039]

As described above, in the invention according to claim 1 of the present invention, the groundwater which flows in by inflowing the groundwater from the water passage provided at the lower end of the casing pipe buried in the ground is pumped up. Prior to pumping with water, pressurized water is pumped into the ground from the water passage provided at the lower end of the casing pipe to split the ground around the lower part of the casing pipe with pressurized water to form a split water passage. After performing the ground reforming process to reform the ground, and after performing this ground reforming process, let the groundwater flow into the casing pipe from the water passage part through the split water passages formed in the surrounding ground by the pumping means. Since the main pumping process is carried out, the surrounding ground can be modified before the main pumping so that a split water passage can be formed in the ground around the lower part of the casing pipe. Oh Through beforehand formed was split 裂通 waterways can catchment smoothly inside the casing pipe from the water passing portion,
Even if the ground surrounding the lower part of the casing pipe is difficult to pass water, or if the location where groundwater exists in the ground and the water passage part do not match, water is effectively collected in the casing pipe. Then, the main pumping can be efficiently performed by the pumping means.

According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, the ground around the lower part of the casing pipe is split by pressurized water to form a split water passage. When reforming the surrounding ground, pressurized water is continuously pumped to the ground around the lower part of the casing pipe, so before performing the main pumping, a split water channel is formed in the ground around the lower part of the casing pipe in advance. When reforming the surrounding ground, a simple method of continuously sending pressurized water to the ground around the lower part of the casing pipe is used to form a split water passage around the lower part of the casing pipe to facilitate water flow. The ground can be modified.

According to the invention of claim 3, in addition to the effect of the invention of claim 1, the ground around the lower part of the casing pipe is split by pressurized water to form a split water passage. In modifying the surrounding ground, pressurizing water to the ground and pumping the saturated groundwater by pumping the pressurized water to the ground and pumping it by pumping means are repeated alternately. Before performing the main pumping, pressurizing water is continuously supplied to the casing pipe before reforming the surrounding soil so that a split water passage is formed in the surrounding soil at the bottom of the casing pipe. By pumping to the ground around the lower part, the ground around the lower part of the casing pipe can be easily cleaved, and the clogging particles generated by the cleaving due to the vacuum suction and pumping can be removed by suction and repeated. In which it is ground reforming blinding particles are removed through water to easily form a split 裂通 waterways become smooth Succoth.

According to the invention of claim 4, in addition to the effect of the invention of claim 3, the water supply valve is opened by the water supply pump with the on-off valve and the air valve closed. The pressurized water is sent from the water passage part into the ground by sending the pressurized water into the casing pipe buried in the ground, and the pressurized water pressure feeding process of splitting the ground around the lower part of the casing pipe with the pressurized water is carried out. With the pump stopped and the water supply valve closed and the on-off valve and air valve open, the pump and vacuum pumps are operated to vacuum suction the groundwater in the ground and the clogging particles in the ground into the casing pipe. While carrying out the washing pumping step of pumping with the pumping pump while repeating the pressurized water pressure feeding step and the washing pumping step alternately, the opening / closing valve and the pumping pump, the air valve and the vacuum pump , Only operates the opening and closing and the operation and stopping of the water supply pump and water valve, and pumping of the pressurized water of the ground,
It is possible to reform the ground by alternately sucking the groundwater in the ground saturated with the pressured water to the ground in a vacuum and pumping it by the pumping means, thereby removing the clogging particles and passing water. The ground can be reformed by easily forming a smooth split water passage.

According to the invention of claim 5, in addition to the effect of the invention of claim 3, water is supplied by opening the water supply valve with the on-off valve closed and the air bleeding valve open. Pressurized water is pumped into the casing pipe and the casing pipe buried in the ground is filled with pressurized water, the air vent valve is closed, and then the pressurized water is pumped into the casing pipe by the water pump to bring the pressurized water from the water passage into the ground. The pressure water is pumped to the ground and the ground around the lower part of the casing pipe is split with pressurized water.Then, the water pump is stopped and the water valve is closed, and the air vent valve is closed. A vacuum space is created in the upper part of the casing pipe by operating the open pump and pumping the water in the casing pipe, and the suction generated by the vacuum generated in the casing pipe causes groundwater in the ground Performing a washing pumping step of pumping water with a pumping pump while sucking clogging particles in the ground into the casing pipe together, and repeating the pressurized water pressure feeding step and the washing pumping step alternately, an on-off valve and a pumping pump, By simply opening / closing and operating / stopping the air bleeder valve, water pump and water supply valve, pressurized water can be sent to the ground by a simple method and groundwater in the ground that has become saturated due to the pressurized water being sent to the ground. It is possible to reform the ground by alternately sucking the water in a vacuum and pumping it with a pumping means.Especially, without using a vacuum pump, the upper part of the casing pipe can be evacuated by a simple method. The ground water and clogging particles can be sucked into the casing pipe by vacuum suction.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a sequence of a ground improvement process according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the sequence of the ground improvement process of the above.

FIG. 3 is an explanatory view of a main pumping step of the above.

FIG. 4 is an enlarged cross-sectional view of a lower portion of an example of a casing tube used in the above.

FIG. 5 is an explanatory diagram showing the sequence of a ground improvement process according to another embodiment of the present invention.

FIG. 6 is an explanatory view showing the sequence of the ground improvement step of the above.

FIG. 7 is an explanatory view showing the sequence of the ground improvement step of the above.

FIG. 8 is an explanatory view showing the sequence of the ground improvement step of the above.

FIG. 9 is an explanatory view showing the sequence of the ground improvement process of the above.

[Explanation of symbols]

1 ground 2 water passage 3 casing tubes 4 Pumping means 5 Air bleeding valve 6 open / close valve 7 Pumping pipe 8 pumping pump 9 Vacuum pump 10 Air valve 11 vacuum tubes 12 Water pump 13 Water valve 14 water pipe

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shuichi Matsumura             1-7-24 Otemae, Chuo-ku, Osaka Nariyuki             Industry Co., Ltd. F-term (reference) 2D043 CA04 DA01 DA04

Claims (5)

[Claims] 1. A water passage portion provided at a lower end portion of a casing pipe prior to inflowing groundwater from a water passage portion provided at a lower end portion of a casing pipe buried in the ground and pumping the inflowing groundwater by a water pumping means. The ground reforming process is carried out by pumping pressurized water from the ground into the ground to split the ground around the lower part of the casing pipe with the pressurized water to reform the surrounding ground so as to form a split water passage. After carrying out, the groundwater pumping method is characterized by carrying out the main pumping step of pumping the groundwater by flowing it into the casing pipe from the water passage part through the split water channel formed in the surrounding ground by the pumping means. 2. The pressurized water is continuously pumped to the ground around the lower part of the casing pipe when the ground around the lower part of the casing pipe is split by pressurized water to reform the surrounding ground so as to form a split water passage. Claim 1 characterized by the above.
Groundwater pumping method described. 3. When the ground around the lower part of the casing pipe is split with pressurized water to reform the surrounding ground so as to form a split water passage, the pressurized water is fed to the ground and the pressurized water is fed to the ground. Suctioning groundwater in the saturated ground with a vacuum and pumping it with pumping means,
The groundwater pumping method according to claim 1, wherein the ground is reformed by alternately repeating and. 4. A pumping pump is provided at the lower end of a pumping pipe having an opening / closing valve in reforming the surrounding ground so as to form a split water passage by splitting the ground around the lower part of the casing pipe with pressurized water. A vacuum pipe which constitutes a pumping means, has a pump pipe inserted into a casing pipe whose upper end is closed, and places a pump in the lower part of the casing pipe, and a vacuum pipe having an air valve connected to the vacuum pump at the upper end of the casing pipe. Is connected to the water pipe with a water feed valve connected to a water feed pump for supplying pressurized water into the casing pipe, and the water feed valve is opened with the on-off valve and air valve closed, and the ground is fed by the water feed pump. Pressurized water is pumped into the ground from the water passage section by pumping the pressurized water into the casing pipe buried in the ground, and the ground around the lower part of the casing pipe is split by the pressurized water. After the water feeding process is performed, the water pump is stopped, the water valve is closed, and the open / close valve and the air valve are opened to operate the pump and the vacuum pump to vacuum the groundwater in the ground. The cleaning pumping step of pumping a clogging particle in the ground into the casing pipe together with pumping with a pump, and repeating the pressurized water pumping step and the cleaning pumping step alternately. Groundwater pumping method described. 5. A pumping pump is provided at the lower end of a pumping pipe having an opening / closing valve when reforming the ground surrounding the lower part of the casing pipe with pressurized water to form a split water passage. A pumping means is constituted, the pumping pipe is inserted into a casing pipe whose upper end is closed, a pumping pump is arranged in the lower part of the casing pipe, and an air venting portion having an air vent valve is connected to the upper end of the casing pipe. A water supply pipe with a water supply valve connected to a water supply pump for supplying pressurized water to the casing pipe is connected, and the water supply valve is opened with the on-off valve closed and the air bleeding valve opened, and the water supply pump opens the casing pipe. When the casing pipe buried in the ground is filled with the pressurized water, the air vent valve is closed, and then the pressurized water is pumped into the casing pipe by the water pump. Pressurized water is pumped into the ground from the water passage to split the ground around the lower part of the casing pipe with the pressurized water.Then, the water pump is stopped and the water supply valve is closed and air is removed. With the valve closed, open the on-off valve and operate the pump to pump the water in the casing pipe to form a vacuum space in the upper part of the casing pipe, and the vacuum generated in this casing pipe sucks the groundwater in the ground. The cleaning pumping step of pumping water with a pump while suctioning clogging particles in the ground into the casing pipe is also performed, and the pressurized water pressure feeding step and the cleaning pumping step are alternately repeated. Groundwater pumping method.