JPH0524284B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for installing a deep well for pumping out groundwater from the ground to lower the groundwater level or improve the ground.

<Conventional Technology> When constructing a structure, a groundwater lowering method is often adopted in order to increase the strength and stability of the foundation ground, or to ensure workability during excavation. There are various methods for this construction, one of which is the deep well installation method, which involves drilling a hole in the ground and installing a strainer (water collection pipe) therein.

An overview of conventional deep well installation methods includes drilling methods using a Benoto excavator, a method using a Borrig machine, and a method using an earth auger machine, among which the method using a Benoto excavator is considered to be the most reliable method. There is. In this construction method, the casing tube is pressed into the ground while rocking, and the inside of the casing tube is excavated with a grab hammer. When the excavation depth reaches a predetermined level, a strainer with a water passage hole (slit) is inserted. Next, a deep well is installed by pulling out the casing tube while stuffing filter material between the strainer and the casing tube.

<Problems to be Solved by the Invention> However, in the conventional deep well installation method, it is necessary to perform the operations of press-fitting and adding the casing tube alternately while excavating with a grab hammer, which is time-consuming and labor-intensive. However, there were problems such as the efficiency of excavation work was extremely poor and the costs of work and equipment were high.

This invention was made in view of these conventional problems, and provides a method for installing a deep well that can reliably and economically install a deep well with a diameter of 30 to 60 cm in a short time and with relatively simple work. The purpose is to

<Means for Solving the Problems> The deep well installation method according to the present invention involves driving a casing tube containing a strainer and having a retractable shoe at its tip to a predetermined depth using a driving device; After or in parallel with the driving, a filter material is introduced between the strainer and the casing tube, and after or in parallel with the injection, the casing tube is pulled out of the ground, and the strainer is left in the ground. I was there.

<Function> The casing tube of the present invention includes a strainer for water collection from the time it is driven into the ground, and the foot of the tip opening is closed, so that the strainer and the casing tube are driven together with the casing tube. Reach a predetermined depth in the ground. Next, when the filter material is put in and the casing tube is pulled out, the shoe at the end of the casing tube opens, and the strainer contained in the casing tube and the filter material put in are left in the ground. In this way, the drilling of the hole, the installation of the strainer in the hole, and the introduction of the filter material are carried out simultaneously as a whole, making it possible to install the deep well quickly and easily.

<Embodiment of the Invention> An embodiment of the invention will be described below with reference to the drawings. FIG. 1 is a process diagram of a deep well installation method according to the present invention, and FIG. 2 is a block diagram of a sand drain driving machine as a driving device used in this method.
In the figure, 1 is a caterpillar vehicle, 2 is a leader installed upright on the caterpillar vehicle 1, and 3 is a wire rope suspended above the leader 2. A vibro hammer 4 is suspended from one end of the wire rope via a shock absorber 8. There is. 5 is a hopper connected to the vibro hammer 4; 6 is a bucket that moves up and down along the leader 2 to transport gravel as a filter material; 7 is a casing tube connected to the bottom of the hopper 5;
A strainer such as a flexible tube is inserted into the casing tube 7. A spacer is attached to this strainer to maintain a constant gap with the casing tube 7. In addition, in FIG. 1, 9 is a pulley that supports the wire rope 3;
10 is another pulley that supports the hanging wire rope 11 inserted into the outer tube 7 from the lower part of the hopper 5; 12 is a water-permeable pipe-shaped strainer such as a flexible tube; and 17 is a shoe (bottom) fixed to the casing tube. lid).

Next, referring to FIG. 1, the deep well installation method will be sequentially explained.

First, using the sand drain driving machine mentioned above,
Place casing tube 7 at the deep well installation location, and
Set up as shown in Figure a. That is, the casing tube 7 is lifted up to a predetermined height by the wire rope 3. Next, the hanging wire rope 11 suspended inside the lifted casing tube 7,
The casing tube 7 is taken out from the lower end thereof and its lower end is locked to the upper end of the water permeable strainer 12 as shown in FIG. 1b. here,
A hanging wire rope 11 is wound up via a pulley 10 by a motor or the like, and the strainer 12 is pulled up to a predetermined height as shown in FIG. 1c.
At this time, the lower end of this strainer 12 is made to fit within the casing tube 7.

Subsequently, the wire rope 3 is loosened, and the casing tube 7 and strainer 12 are lowered to the ground as shown in FIG. 1d. At this time, the shoe 12 is closed. Here, the casing tube 7 is pressed by the vibrohammer 4 in the driving device as shown in FIG.
Then, as shown in FIG. When the final depth is reached,
The casing tube 7 is pulled out, and a filter material 13 such as gravel is introduced into the space between the casing tube 7 and the strainer 12. Note that the filter material 13 may be introduced in parallel with the insertion of the casing tube 7, as shown in FIG. 1e. Then, when the casing tube 7 is pulled out by about 1 m with a vibrohammer, the shoe 17 fixed at the tip opens its open end due to friction with the soil, and the strainer 12 inside is removed together with the filter material 13 that is introduced. Stay within the ground. The filter material 13 can be easily introduced by transferring it from the basket 6 guided by the leader 2 to the hopper 5 below the vibratory hammer 4. Note that at this time, the filter material 13 is attached to the strainer 12.
To prevent it from getting inside, use this strainer 1.
It is necessary to cover the top end of 2 with a lid 14.

In this way, by alternately pulling out the casing tube 7 and inserting the filter material 13, the strainer 1 contained in the casing tube 7 is placed in the ground, as shown in FIG. 1g.
2 is left together with the filter material 13 surrounding it. Therefore, in the lower part of this strainer 12,
If a submersible pump 15 is installed as shown in FIG. 1h, underground water can be discharged to the surface through a pipe 16. That is, by using this strainer 12 as a deep well and forcibly pumping up water with a pump, the groundwater level can be lowered.

Note that the strainer 12 may be made of a steel pipe or a hard vinyl chloride pipe, but if a commercially available flexible water collection pipe is used, it is extremely easy to insert it into the casing tube 7 even if it is long, and there is no risk of corrosion. .

In this way, the installation of a deep well can be carried out extremely quickly and easily by simultaneously inserting the casing tube 7 into the ground together with the strainer 12 and adding the filter material 13 at the same time, thereby reducing the construction period. It is possible to shorten the time.

Note that if the casing tube 7 is driven in while blowing out high-pressure water or air from the lower end of a pipe (not shown) that runs along the casing tube 7, a deep well can be installed without vibration or noise. be able to.

<Effects of the Invention> As described above, according to the present invention, the casing tube containing the strainer is penetrated into the ground by the driving device, so the casing tube and the strainer can be inserted into the ground at the same time. At the same time, since the filter material is thrown in parallel with the above-mentioned drawing, the installation time of the deep well, that is, the construction period, can be significantly shortened, the work is simplified, and the economical efficiency is improved. In particular, when performing ground improvement using sand drains and groundwater lowering methods in areas with soft ground, the sand drain driving machine can be used as is for installing deep wells, making it significantly more economical than conventional methods.

[Brief explanation of drawings]

FIG. 1 is a working explanatory diagram showing a deep well installation method according to the present invention, and FIG. 2 is a schematic diagram of a sand drain driving machine. 4... Driving device, 7... Casing tube, 12... Strainer, 13... Filter material,
17... Shoes.

Claims (1)

[Claims] 1 The process of driving a casing tube containing a strainer into the ground to a predetermined depth using a driving device, and placing a filter material in the space between the strainer and the casing tube in parallel with or after the driving process. A method for installing a deep well, comprising: a step of charging; and a step of pulling out the casing tube from the ground in parallel with or after the charging step and installing the strainer in the ground.