JP2002357072A - Shaft sinking casing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a casing for sinking a shaft capable of exchanging an excavating blade during the execution of works and recovering it after the execution of works. SOLUTION: The casing 1 for sinking the shaft is composed of a cylindrical casing body 2, a plurality of arcuate excavating-blade mounting members 5 fixed along the lower end section of the casing body 2 by bolts 3 and a plurality of cone cutters (the excavating blades) 6 fixed onto the mounting members 5 at regular intervals. According to such constitution, since the cone cutters 6 can be detached and mounted from the inside of the casing body 2 under the state in which the casing 1 is pressed into a ground, the abraded and damaged cone cutters 6 can be exchanged during the execution of works, and be removed and recovered from the casing body 2 left to stand in soil after the execution of works. Even when a soil character different from a prediction appears after the start of excavation works, exchanges to the cone cutters 6 in conformity with the soil character are also enabled easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft excavation casing used for constructing a shaft in the ground in civil engineering work or the like.

[0002]

2. Description of the Related Art When constructing a shaft from the ground to the ground in civil engineering work or the like, a cylindrical shaft excavating casing is clamped by a press-fitting device equipped with an excavating machine,
After press-fitting the shaft excavation casing into the ground while giving reciprocating rotational movement around its axis or rotational movement in one direction,
A process of excavating earth and sand in the casing by a club bucket or the like and discharging the soil to the ground side, and repeatedly performing press-fitting of the casing and excavation in the casing until the construction depth of the shaft is reached is adopted.

The shaft excavation casing used here is:
A plurality of the shafts are press-fitted to a predetermined depth while being sequentially connected in the axial direction. As a vertical shaft excavation casing to be press-fitted first, the one shown in FIGS. 9 and 10 is used. . Shaft excavation casing 90 shown in FIG.
Is a cylindrical casing body 91 and a casing body 9.
1 and a saw blade-shaped excavating blade 92 made of a mild steel plate, which is welded to the lower end of the cutting blade 92. Further, in a shaft excavation casing 95 shown in FIG.
A plurality of excavating blades 97 made of cemented carbide are attached to the lower end portion of the base 6 at predetermined intervals.

[0004] These shaft excavation casings 90, 95
In addition to functioning as an excavation means when forming a shaft in the ground, it also serves as an earth retaining work to prevent collapse of the shaft due to earth pressure by leaving it in the soil after construction of the shaft.

[0005]

In the conventional shaft excavating casing, since the excavating blade is welded to the lower end of the casing body, even if the excavating blade is worn or damaged during construction, it is replaced. I can't. For this reason, it is often necessary to continue the excavation work in a state where the excavation ability is reduced, and a work period may be delayed due to a decrease in work efficiency.

When a single shaft is constructed using a conventional shaft excavating casing, the material of the excavation blade, the shaft depth,
Depending on the soil properties, many of the excavating blades themselves can be reused when the shaft construction is completed. However, in the conventional shaft excavation casing, the excavation blade is welded to the casing main body, and it is extremely difficult to remove the excavation blade after construction.Therefore, the excavation blade cannot be collected and reused. And is left in the soil, wasting metal resources.

[0007] An object of the present invention is to provide a shaft excavating casing capable of exchanging excavating blades during construction and recovering excavating blades after construction.

[0008]

A shaft shaft excavation casing according to the present invention comprises a cylindrical casing body, and an excavating blade detachably fixed to an end of the casing body from the inside of the casing body. It is characterized by. With such a configuration, the drilling blade can be detached and attached from the inside of the casing body in a state in which the shaft is inserted into the ground, so that the worn or damaged drilling blade is replaced during the construction. It is possible to remove the excavating blade from the casing body left in the soil after installation or to collect it. In addition, even if soil different from the predicted one appears after the start of the excavation work, it is possible to easily replace the excavation blade with an excavation blade suitable for the soil.

Here, by fixing the digging blade to the end of the casing main body via a digging blade mounting member that can be divided into a plurality of parts, the attaching and detaching operation of the digging blade can be efficiently performed from the inside of the casing main body in a short time. It can be executed well and the workability is improved. In addition, as the excavation blade attachment member, a plurality of arc-shaped members that can be locked by bolts and nuts along the lower end portion of the casing main body are preferable, and if the excavation blade is fixed to such an arc-shaped member. The attachment and detachment of the excavating blade can be performed by attaching and detaching the arc-shaped member.

By using a cemented carbide digging blade as the digging blade, it is possible to efficiently perform digging work on relatively hard rock. In addition, as a cemented carbide, WC-Co system, WC-TiC-Co system, WC-Ti
C-TaC (NbC) -Co system, WC-TaC (Nb
C) -Co type and the like are preferable.

On the other hand, if a cone cutter is used as the excavating blade, the cutter section becomes rotatable, so that the excavation resistance is reduced and the torque of the press-fitting device can be reduced.

[0012]

FIG. 1 is a bottom view showing a shaft excavation casing according to a first embodiment of the present invention, FIG. 2 is an end view taken along the line AA in FIG. 1, and FIG. 3 is a line BB in FIG. FIG. 4 is a cross-sectional view showing another embodiment of the excavating blade mounting member.

The shaft shaft excavating casing 1 of the present embodiment comprises a cylindrical casing body 2, a plurality of arc-shaped excavating blade mounting members 5 fixed along the lower end of the casing body 2 with bolts 3, It is composed of a plurality of cone cutters 6 fixed to the mounting member 5 at regular intervals. The cone cutter 6, which is a kind of the excavating blade, includes a pedestal portion 6a fixed to the excavating blade mounting member 5, and a cutter portion 6c pivotally supported by the pedestal portion 6a so as to be rotatable about 45 degrees from the vertical. A large number of cutting tips 6b are protrudingly arranged on the outer surface of the configured and cone-shaped cutter 6c.

The arc-shaped excavating blade mounting member 5 is formed by dividing the periphery of the lower end of the casing main body 2 into three parts, and extends along the lower surface of the circular locking member 7 fixed to the lower end of the casing main body 2. The digging blade attachment member 5 is mounted, and a plurality of bolts 3 inserted from the upper surface of the locking member 7 are fixed to the digging blade attachment member 5 by screwing. In FIGS. 1 to 3, reference numeral 4 denotes a boundary portion between the adjacent excavating blade mounting members 5.
The cone cutter 6 is fixed by bolting or welding its pedestal portion 6a to the lower surface of the excavating blade mounting member 5.

The shaft excavating casing 1 of the present embodiment has the same function as a conventional shaft excavating casing, and a shaft can be constructed underground using conventional construction machines and construction techniques. When the bolt 1 is pressed into the ground, the cone cutter 6 can be attached to and detached from the casing main body 2 together with the excavating blade mounting member 5 by loosening or tightening the bolt 3 from inside the casing main body 2. Also, the excavating blade mounting member 5 with the cone cutter 6 detached from the casing main body 2 can be pulled up to the ground through the inside of the casing main body 2, and the excavating blade mounting member 5 with the cone cutter 6 can be lifted from the ground to the casing main body. It can be lowered through the inside 2 and attached to its lower end.

Therefore, when the cone cutter 6 is worn or damaged during construction, it can be easily replaced with a new cone cutter 6, and after the construction of the shaft is completed, the casing body 2 left in the soil is removed. The cone cutter 6 can be removed and collected together with the excavating blade attachment member 5. In addition, even if soil different from the predicted one appears in the ground after the start of the excavation work, the cone cutter 6 suitable for the soil may be used.
It can be easily exchanged for

Since the cone cutter 6 is fixed to the lower end of the casing body 2 via the excavating blade mounting member 5 which can be divided into three, the attaching and detaching operation of the cone cutter 6 can be performed from the inside of the casing body 2 in a short time. And the workability is good. As shown in FIG. 4, the cone cutter 6 may be fixed to the lower end of the casing body 2 via an arc-shaped excavating blade attachment member 9 which can be divided into four. In FIG. 4, reference numeral 8 denotes a boundary portion between adjacent excavation blade mounting members 9.

In this embodiment, since the cone cutter 6 in which the cutter portion 6c is rotatable is used as the excavating blade, there is an effect that the excavation resistance is small and the torque of the press-fitting device is small.

Next, a shaft excavation casing 10 according to a second embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 5 and 6, the shaft excavation casing 10 includes a cylindrical casing body 12 and a casing body 1.
2, a plurality of circular arc-shaped excavating blade attachment members 15 fixed to the lower end portion of the second member 2 by bolts 13 along the engaging members 17, and a plurality of excavating blade attaching members 15. It is composed of a plurality of excavating blades 16 fixed at regular intervals. The digging blades 16 have a shape as shown in FIG. 7A, and these digging blades 16 are fixed at regular intervals along the digging blade mounting member 15 as a pair.

As shown in FIG. 5, a pair of excavating blades 16
Are fixed in an inclined state so as to face the inside and outside of the casing body 12 alternately along the circumferential direction of the excavating blade mounting member 15. In FIGS. 5 and 6, reference numeral 14 denotes a boundary portion between the adjacent digging blade mounting members 15, and the digging blade 16 is fixed to the digging blade mounting member 15 by welding.

The shaft excavating casing 10 has the same function as the casing 1 for excavation. When the shaft 10 is pressed into the ground, the bolt 13 is loosened or tightened from the inside of the casing body 12 by pressing. The digging blade 16 can be attached to and detached from the casing body 12 together with the digging blade mounting member 15. Also, the digging blade mounting member 15 with the digging blade 16 detached from the casing main body 12 can be pulled up to the ground through the inside of the casing main body 12, and the digging blade mounting member 15 with the digging blade 16 can be lifted from the ground to the casing main body. It can also be lowered through 12 and attached to its lower end.

The excavating blade 16 has a structure as shown in FIG.
The cutting edge 16a made of cemented carbide is joined to the lower end corner of the rectangular parallelepiped main body 16b, as shown in FIG.
Since the pair of digging blades 16 are fixed in an inclined state so as to face the inside and outside of the casing body 12, it is possible to efficiently perform digging work on relatively hard rock.

Note that, instead of the excavating blade 16, FIG.
As shown in the figure, a shogi piece-shaped cutting blade 18 in which a wedge-shaped cutting blade 18a is joined to the lower end of a substantially rectangular parallelepiped main body 18b.
Can also be used. When the above-described cutting blade 16 is used, the casing body 12 is rotated only in one direction to perform the excavation work. However, when the cutting blade 18 is used, the casing body 12 is rotated in both directions to perform the excavation work. There is a feature that can be. Other functions, effects, and the like are the same as those of the casing 1 for excavation of the first embodiment.

[0024]

According to the present invention, the following effects can be obtained.

(1) Since a cylindrical casing body and an excavating blade fixed to an end of the casing main body so as to be detachable from the inside of the casing main body are provided, exchange and excavation of excavating blades during construction are performed. Recovery of the excavation blade later becomes possible.

(2) The digging blade is fixed to the end of the casing body via a digging blade mounting member which can be divided into a plurality of parts, so that the work for attaching and detaching the digging blade can be efficiently performed from the inside of the casing body in a short time. It can be executed well and the workability is improved.

(3) By using a cemented carbide excavation blade as the excavation blade, it is possible to efficiently perform excavation work on relatively hard rock.

(4) By using a cone cutter as the excavating blade, the cutter can be rotated, so that the excavation resistance is reduced and the torque of the press-fitting device can be reduced.

[Brief description of the drawings]

FIG. 1 is a bottom view showing a shaft excavation casing according to a first embodiment of the present invention.

FIG. 2 is a partially omitted sectional view taken along line AA of FIG. 1;

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a cross-sectional view showing another embodiment of the excavating blade mounting member.

FIG. 5 is a bottom view showing a shaft excavation casing according to a second embodiment of the present invention.

FIG. 6 is a sectional view taken along line CC of FIG. 5;

7A is a perspective view of an excavation blade constituting the shaft excavation casing of FIG. 5, and FIG. 7B is a perspective view of an excavation blade according to another embodiment.

FIG. 8 is a partial cross-sectional view showing a positional relationship of a digging blade.

FIG. 9 is a longitudinal sectional view showing a conventional shaft excavation casing.

FIG. 10 is a longitudinal sectional view showing a conventional shaft excavation casing.

[Explanation of symbols]

 1,10 Vertical shaft excavating casing 2,12 Casing body 3,13 Bolt 4,8,14 Boundary part 5,9,15 Excavating blade attaching member 6 Cone cutter 6a Pedestal 6b Cutting tip 6c Cutter 7,17 Locking member 16 , 18 drilling blade

Claims (4)

[Claims] 1. A shaft shaft excavation casing comprising: a cylindrical casing main body; and an excavating blade fixed to an end of the casing main body so as to be detachable from the inside of the casing main body. 2. The shaft shaft excavating casing according to claim 1, wherein the excavating blade is fixed to an end of the casing body via a plurality of excavating blade mounting members that can be divided. 3. The shaft excavating casing according to claim 1, wherein a cemented carbide excavating blade is used as the excavating blade. 4. The excavating casing according to claim 1, wherein a cone cutter is used as the excavating blade.