JP2000104262A - Shaft excavating in settlement of caisson and execution work to projected ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the execution method capable of shortening the term of works by forming a plurality of group of leading holes in advance on the arbitrary places over the whole surface of the natural ground of a central part from an outer peripheral part of a caisson on the projected ground for settling the caison, and charging the filler material into the hole. SOLUTION: A plurality of leading holes are excavated on the natural ground of the projected ground for settling as caisson, and the filler material 2 such as gravel or the like is charged into the holes. The leading holes are formed on the arbitrary places from an outer peripheral zone of the caisson of large diameter to a central part, and totally forms a gravel column layered shaft 4. Then the caison of large diameter is placed, and the natural ground inside is excavated, discharged and gravitated. When one of the holes is embedded, a next caisson of large diameter is supplemented to an upper part to be built. That is, the caisson of large diameter is settled by self-weight by filling a group of leading holes temporarily hollowed, with the gravel or the like, and repeating the digging and discharging works. Whereby the caisson can be settled for a short time even in the coarse bed including the rock, base rock or the like, and the cost can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for smoothly laying a caisson on all types of ground, such as soft ground, rocks, rocks, and other grounds where it has been difficult to construct a shaft with a large diameter and a large depth. Things.

[0002]

2. Description of the Related Art Conventionally, when a caisson is laid, a deep layer method, a support press-fitting method, and the like have been implemented.
In each case, it took a long time to excavate, leading to a rise in construction costs. The applicant has been a specialist in drilling wells for many years.In recent years, the settlement of the ground has been remarkable in urban areas. And, the construction method of excavating the planned site of the shaft construction of the present invention in advance, the applicant for many years,
Although it was held as "know-how", it is disclosed in this application.

[0003]

For example, the deep construction method
A caisson is placed on the site to be excavated, excavating the inside and below of the caisson and discharging sediment, etc.When the lower caisson is buried, the next caisson is placed on top of it and sinks by its own weight. It will be buried to build a deep shaft,
If you hit a large rock or bedrock while excavating the shaft, a human descends into the shaft and crushes the rocks or bedrock and removes it.
Not only is it dangerous, but there are problems such as a decrease in excavation efficiency. In addition, the support press-in method involves driving a large number of support reaction piles deep underground to receive a reaction force against press-fitting in the surrounding area before excavating a large-diameter, large-depth shaft, and supports the support press-fit on the ground. Press-fitting girders had to be assembled, and large-scale temporary equipment was required.

[0004]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a method for excavating a vertical shaft in the construction of a caisson.
As a method of forming a planned shaft shaft in advance, a group of leading holes (guide holes) is excavated in a mountain where a caisson is to be placed, and a filler is charged into each of the leading holes to greatly shorten the construction period. The disclosed construction method is disclosed.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION A number of small-diameter leading holes are excavated in advance, as required, at a scheduled shaft construction site (predetermined position).
This is a construction method in which a filler such as gravel is charged into each of the leading holes, and sedimentation of a caisson can be carried out extremely easily. If the ground (stratum) at a predetermined position of a shaft is good, a well-known construction method is used. Excavating the ground at the inner part of the caisson with a normal excavator and discharging earth and sand, etc.If the stratum is in a bad state such as rocks overlapping, the entire surface of the planned site is Construct a group of hollow leading holes, see (FIG. 2),
A filler is injected into the group of leading holes to create a state in which a huge gravel column appears in the ground. (See FIG. 3).
That is, the number of leading holes is adjusted according to the state of the formation.

Next, when a caisson is placed at a predetermined position on the surface of the huge gravel pillar and the filler such as gravel on the inner peripheral portion of the caisson is discharged by a bucket or the like, the caisson descends very easily. It is. (See FIG. 4).

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a method for forming a planned site according to the present invention.

According to the present invention, as shown in FIG. 2, a plurality of leading holes 1 are excavated in the ground where a caisson is to be laid.
Next, a filler 2 such as gravel is put into each leading hole 1.
That is, as shown in FIG. 4, the leading hole 1 is formed at an arbitrary portion from the outer peripheral region of the large-diameter caisson 3 to a central portion, so that, as shown in the conceptual diagram of FIG. As a whole, a pit 4 in the form of a gravel column that is extremely easy to excavate is formed.

In this state, the large-diameter caisson 3 is placed on the planned site where the shaft 4 is formed, and the ground inside the large-diameter caisson 3 is excavated and discharged by a drilling device, so that the large-diameter caisson 3 is formed. It sinks.

That is, the site where the shaft 4 is to be formed is:
It focuses on the fact that a small-diameter excavator can excavate freely from the ground and can be excavated on any ground, even on solid ground with rocks and rocks. It is filled with gravel, etc., and the excavation equipment is used to excavate the huge gravel pillar (tubular) shaped reference site (Fig. 3).
The large-diameter caisson 3 molded with concrete or the like slowly sinks by its own weight, and when one large-diameter caisson 3 is buried, it is constructed while adding the next large-diameter caisson 3 upward.

[0011]

As described above, the present invention excavates a stratum in which a caisson is supposed to be laid, and is composed of only a gravel cylinder layer. This is an epoch-making and extremely effective invention in which a caisson can be sunk and work efficiency is improved to reduce construction costs.

[Brief description of the drawings]

FIG. 1 is an explanatory plan view showing a state in which a scheduled place formed by filling a guide hole with a filler is formed.

FIG. 2 is an explanatory perspective view of a main part showing a hollow state after excavation of a leading hole.

FIG. 3 is an explanatory cross-sectional view of a main part showing a state where a filler is charged into a group of leading holes.

FIG. 4 is an explanatory view of a state in which a caisson is sinking while discharging filler.

[Explanation of symbols]

 1. Lead hole 2. Filler 3. Caisson 4. Shaft.

Claims (1)

[Claims] 1. A method for forming a planned shaft pit in advance when excavating a shaft in the construction of a caisson, wherein a plurality of pits are formed at an arbitrary position from the outer periphery of the caisson to an arbitrary portion of the ground in the center. A method of excavating a shaft and setting a planned site in a caisson sunk, characterized by excavating a guide hole, forming a group of guide holes, and charging a filler into each of the guide holes.