JPS61142231A - Settlement of well cylinder casing - Google Patents

Abstract

PURPOSE:To exactly and quickly settle a well by a method in which a cutting edge device to excavate the ground in a cylindrical form is divided into many parts, and the cutting edges are each separately pushed down by jacks provided to the tips of the cutting edges to proceed stagewise excavation operations while making local sheathing. CONSTITUTION:A cylindrical back plate 1 with a ring 2 is penetrated into a well hole excavated in a cylindrical form, and a cutting edge device 3 having a forward jack 4 is provided on the periphery of the lower part of the ring 2. A backward jack 5 is provided to the upside of the ring 2, and one or two segments (a) are set above the jack 5. The jack 4 is extended to advance each cutting edge 3 to excavate the ground while making local sheathing. At the same time as the jack 4 is contracted, the jack 5 is extended simultaneously, the ring 2 and the back plate 1 are pushed down, and the segments (a) are housed in the well hole and assembled.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Object of the Invention The present invention relates to a construction method for sinking a well made of concrete, segments, liner plates, etc. into the ground.

In the past, especially when constructing wells for water collection, excavation using cutting blades was difficult due to collapsible geological formations, boulders, and quick sand phenomena.
In many cases, it was impossible to sink by gravity. Therefore, the present invention provides a new construction method that is effective for installing a well in a stratum where it is likely that various obstacles will enter the cutting edge of the well during construction, making it impossible to excavate and sink the well. The purpose is to

2. Structure of the invention The construction method of the present invention will be explained based on the embodiments shown in the drawings.

Figures 1 to 6 show the case of strata that are likely to be collapsible.

First, a cylindrical back plate (1) with a suitable medium ring (2) placed around it is inserted into a well hole that has been excavated in a cylindrical shape to a depth of about 4 m underground. On the lower side of the ring (2),
A cutting edge body (3) which is divided into a large number of pieces is provided around the periphery, and inside each cutting edge body, the head is connected to the ring (21).
It is equipped with an advanced jack (4) that is in contact with the lower surface of.

In addition, the upper surface of the ring (2) is provided with several reverse jacks (5) at appropriate intervals, and above the head of the reverse jack there are one or two segments (a).
is listed. (6) is a cover plate provided on the ring (2) so as to cover the entire inner group of the cutting edge body (3).

When excavating now, from the point where the bed excavation is progressing, extend each advanced jack (4) sufficiently and insert each cutting edge body (3).
. . . and thereby locally retain the earth. In other words, since the cutting edge bodies (3) are divided into many parts, even if there are boulders or quick sand, each cutting edge body will move forward while locally retaining the earth. Fig. 2 shows the local earth retaining state, and Fig. 3 shows the final earth retaining state.

Next, when the appropriate number of reverse jacks (6) installed above the ring (21) are extended all at once, the reverse jacks (5)
As the ring (2) and back plate (1) expand, the ring (2) and the back plate (1) are pushed down, and at the same time, the entire advanced jack (4) is retracted. At this time, if the downward stroke of the reverse jack (5) is shorter than the height of the segment, the downward movement of the jack is repeated 2 to 3 times, and the downward stroke of the backward jack (5) is shorter than the segment height. If the height is greater than or equal to , the jack only needs to be pressed down once. (4th
(See figure) After forming a space (7) large enough to accommodate the segments using the reverse jack (5), each block of the segment Ha) is accommodated therein and assembled. At this time, the lower surface of this segment < af is the reverse jack (5
) will be placed on the head of.

(See Figures 5 and 6) Figures 7 to 10 show the method of submersion in strata that are not likely to collapse.

In this method, the jack (4) is pressed down and each cutting edge body (3) is pressed down.
)... are advanced individually and excavated while locally retaining the earth, and when all the cutting edge bodies are aligned, the segmented blade placed on the ring (2)) (a) The entire body sinks due to its own weight. I come to do it. Therefore, by digging the cutting edge body (3)... by pressing down the jack (4)..., the space (7) that can accommodate the segment becomes the uppermost segment (a).
) (see Figure 10). In the bent state, a new segment (a) block can be inserted from the ground and assembled.

In addition, in FIGS. 11 to 14, the back plate (1) is configured to be individually separated like a trunk pile,
We are planning to use a submersion method in geological strata that are likely to slide and be collapsible.

At the tip of each back plate (1), there is a cutting edge body (31).
... and a jack (4)... are provided, and the first segment (4) is placed on the head of the jack. Jyatsuki (4)... is each segment (a)
The cutting edge body (3) is individually advanced by the reaction force of
Excavation is carried out while locally retaining the earth and simultaneously lowering each back plate (1). A spacer front is provided above each jack.

In the underground part excavated in this manner, a space (7) large enough to accommodate the segment is formed, and the block of the segment (a)' is accommodated therein for assembly. (Refer to Figure 14) After completing the construction of the well by installing the segments in stages at the target depth using each of the above methods, all the jacks, cutting edge bodies, rings, etc. at the tip are disassembled and placed on the ground. to recover.

3. Effects of the Invention As described above, the present invention is constructed by dividing the cutting edge body that excavates in a cylindrical shape into a large number of parts, and each cutting edge body is provided with a jack, so that the cutting edge body can be individually pushed down to move locally. Since this method is characterized by excavating in stages while retaining the earth, one segment can be reliably installed every 1m of excavation, even in geological strata that may be collapsible. However, by repeating this process, it is extremely effective as a construction method that can quickly perform segments to the desired depth.

[Brief explanation of the drawing]

The drawings show each embodiment of the present invention, and FIGS. 1 to 6 are front cross-sectional views of the main parts of the first embodiment, and FIGS. 7 to 10 show the main parts of the second embodiment. FIGS. 11 to 14 are front sectional views showing the operation of the main parts of the third example. Patent applicant Nissaku Co., Ltd. (≧'1)

Claims (2)

[Claims] (1) The cutting edge body that excavates in a cylindrical shape is divided into many parts, and each cutting edge body is equipped with a jack, and the cutting edge body is individually pushed down and moved to perform local soil retaining while gradually The well drilling method is characterized by digging in. (2) A ring is provided around the inner side of the back plate at a suitable position, and an advanced jack is provided inside the cutting edge body which is divided into a number of pieces on the inner side of the lower side of the back plate, and the upper end is in contact with the ring, and the said ring A well sinking method characterized in that an appropriate number of backward jacks are provided on the upper surface of the well, and the advanced jacks are used to excavate in stages, and the backward jacks are used to form segment accommodation intervals.