JP2003003502A - Shield machine for cutting and covering bottom of water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield machine for cutting and covering a bottom of water, which enables excavation using low power. SOLUTION: This shield machine 1 for cutting and covering the bottom of the water is used to construct a tunnel in the bottom of the water; a cutter 3 for excavating sediment is provided on the downside of an end of a shield frame 2; and the shield machine 1 excavates the tunnel in such a manner as to make an upside located in the water and make a downside buried in the sediment at the bottom of the water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water bottom excavation shield machine for constructing a tunnel on a water bottom.

[0002]

2. Description of the Related Art A shield excavator is designed to excavate in the ground by the rotation of a cutter at its tip and the propulsive force of a shield jack. The conventional cutter is provided over the entire front surface of the shield frame.

[0003]

By the way, in the case of constructing a tunnel on the bottom of a sea such as a seabed or a riverbed, conventionally, a shield excavator has been designed so that the entire shield machine is buried in the bottom of the water. However, in the shield machine mentioned above,
Since the whole was buried in the bottom of the water, the cutter was driven on the entire surface of the tip of the shield frame, consuming a lot of power.

Therefore, the present invention has been devised in order to solve the above problems, and an object thereof is to provide a water bottom excavation shield machine capable of excavating with a small amount of power.

[0005]

In order to achieve the above object, the present invention is a bottom excavation shield machine for constructing a tunnel on the bottom of a water, and a cutter for excavating earth and sand below the tip of a shield frame. The upper part is located in the water, and the lower part is buried in the bottom sand and excavated.

According to the above construction, since the lower side of the shield machine is buried in the bottom of the water and excavated, and the cutter is provided only on the lower side, the power for rotating the cutter is reduced and energy saving is achieved. In addition to being achieved, simplification of the device is achieved.

A shield guide portion is provided above the tip of the shield frame so as to cover the upper side of the cutter and to guide the bottom of the water to the cutter side. Is preferred.

Further, it is preferable that the tip of the protruding portion is formed so as to spread to the left and right as it goes backward so as to scrape off the surplus water bottom sediment to the left and right of the shield frame. Further, it is preferable that a ballast tank for storing water is provided inside the protrusion.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a front view showing a preferred embodiment of a water bottom excavation shield machine according to the present invention, and FIG. 2 is a sectional view showing a preferred embodiment of a water bottom excavation shield machine according to the present invention. FIG. 3 is a plan view showing a preferred embodiment of a water bottom excavation shield machine according to the present invention.

First, the structure of the water bottom excavation shield machine according to the present embodiment will be described.

The water bottom excavation shield machine 1 is for constructing a tunnel on the water bottom, and as shown in the drawing, a cutter 3 for excavating earth and sand is provided below the tip of the shield frame 2, and The feature is that the side is located in the water, and the lower side is buried in the bottom sand and excavated.

The cutter 3 is of a spoke type in which a cutter spine 6 extends in a radial direction from a cutter rotating shaft 5 rotated by a motor 4. The cutter rotating shaft 5 is provided so as to pass through the bulkhead 7, and the cutas pork 6 is provided on the front side thereof and the motor 4 is provided on the rear side thereof.

Two cutters 3 are provided adjacent to each other in the left-right direction in the width direction, and the cutters 3 are arranged so that the rotation tracks of the cut-and-spokes 6 overlap each other. Each cutter 3 rotates in the opposite direction synchronously so that the respective cutas pork 6 does not interfere.

At the lower position between the cutters 3 of the bulkhead 7, a sediment inlet 8 for taking in the bottom sand excavated by the cutter 3 is formed. A screw conveyor 9 is provided behind the earth and sand intake port 8 to scrape the water bottom sediment back. The screw conveyor 9 is connected to a device (not shown) for placing water bottom sediment on top of the assembled segment 11.

In FIG. 2, 12 is an erector for assembling the segment 11, and 14 is the assembled segment 1.
The shield jacks for pushing 1 to obtain the propulsion force of the excavation are shown.

On the upper side of the tip of the shield frame 2 (upper half in the present embodiment), a projecting portion 15 for covering the upper side of the cutter 3 is formed. The protrusion 15 has a center portion in the width direction that protrudes forward, and has a horizontal cross section of a substantially triangular shape so that the protrusion 15 spreads to the left and right as going rearward from the center of the width direction. This front portion constitutes a scraping portion 17 for scraping surplus water bottom sediment to the left and right of the shield frame.

On the other hand, the lower end surface of the projecting portion 15 is formed so as to lower downward as it goes backward, and constitutes an inclined guide portion 16 for guiding the excavated water bottom sediment to the cutter 3 (downward) side. ing. The inclined guide portion 16 is inclined at an angle substantially equal to the angle of repose of the water bottom sediment to be excavated.

Inside the projecting portion 15, a ballast tank (shown by a diagonal line descending to the right in the drawing) 18 for storing water is provided. The ballast tank 18 prevents the tip of the water bottom excavation shield machine 1 having a small specific gravity from rising.

Behind the ballast tank 18, side ballast tanks 21 and 22 (indicated by diagonal lines rising to the right in the figure) disposed on the left and right in the width direction are provided. The side ballast tanks 21 and 22 are formed so as to extend vertically from the upper half to the lower half, and enhance the stability of the water bottom excavation shield machine 1 during excavation.

Next, the operation of the water bottom excavation shield machine 1 having the above construction will be described.

The bottom excavator shield excavator 1 has its upper side (upper half in this embodiment) located in the water and lower side (lower half in this embodiment) buried in the bottom sand. To do. Therefore, excavation of the earth and sand is required only on the lower side, and the cutter 3 is provided only on the lower side, so that less power is required to drive the cutter 3.

Further, since the upper side of the water bottom excavation shield machine 1 is exposed in the water, propulsion resistance is reduced, the thrust required for excavation can be reduced, and the number and size of the shield jacks 14 can be reduced. it can. by this,
Energy saving can be achieved and simplification of the device can be achieved.

At this time, the upper side travels in the water bottom sediment which has been raised by water or the promotion of the water bottom excavation shield machine 1, but since the raised water bottom sediment is sludge-like and very soft, Since the separating portion 17 is pushed to the left and right in the width direction (shown by a broken line in FIG. 3), it does not act as a resistance to propulsion and stable propulsion can be achieved.

Further, by providing the inclined guide portion 16 on the protruding portion 15, part of the raised water bottom sediment is guided to the cutter 3 side (indicated by a broken line in FIG. 2). The density of the water bottom sediment around the cutter 3 can be increased, and water can be prevented from being attracted to the vicinity of the sediment intake port 8. As a result, the bottom sediment is constantly positioned around the sediment intake port 8 and water can be prevented from flowing into the screw conveyor 9. As a result, it is possible to prevent the water from being blown up from the screw conveyor 9 into the water bottom excavation shield machine 1.

By the way, the rear end of the water-bottom excavated shield machine 1 is held by the assembled segment 11. However, since the specific gravity of the water-bottom excavated shield machine 1 is smaller than that of water, the tip side thereof is lifted up. I will try. However, according to the present invention, since the ballast tank 18 is provided inside the projecting portion 15 provided at the tip of the shield frame 2, a weight is provided at a position farthest from the fulcrum, and the floating is effectively prevented. It will be possible.

The right and left side ballast tanks 21,
Since 22 is provided, rolling at the time of excavation of the water bottom excavation shield machine 1 can be prevented.

The water-bottom sediment carried by the screw conveyor is placed on the assembled segment 11,
The lifting of the segment 11 is prevented.

In the above-described embodiment, the cutter 3 is of the cut-and-spoke rotary type, but is not limited to this. Of course, other shapes such as an oscillating cutter may be used.

[0030]

In summary, according to the present invention, it is possible to excavate with a small amount of power, energy saving can be achieved, and simplification of the device can be achieved.

Further, it is possible to effectively prevent the floating of the water bottom excavation shield machine.

[Brief description of drawings]

FIG. 1 is a front view showing a preferred embodiment of a water bottom excavation shield machine according to the present invention.

FIG. 2 is a sectional view showing a preferred embodiment of a water bottom excavation shield machine according to the present invention.

FIG. 3 is a plan view showing a preferred embodiment of a water bottom excavation shield machine according to the present invention.

[Explanation of symbols]

1 Underwater excavation shield machine 2 shield frame 3 cutters 15 Projection 16 Inclined guide 18 Ballast Tank

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Claims (4)

[Claims] 1. A water bottom excavation shield machine for constructing a tunnel on the water bottom, comprising a cutter for excavating earth and sand below the tip of the shield frame, the upper side being located in water, and the lower side being in water bottom earth and sand. Underwater excavation shield machine, which is buried and excavated. 2. On the upper side of the tip of the shield frame,
2. A water bottom excavation shield machine according to claim 1, wherein a projection having an inclined guide portion that covers the upper side of the cutter and guides the water bottom sediment toward the cutter is provided at a lower end portion of the cutter. . 3. The water bottom excavation shield machine according to claim 2, wherein the tip of the projecting portion is formed so as to spread to the left and right as it goes backward so as to scrape the surplus water bottom sediment to the left and right of the shield frame. 4. The water bottom excavation shield machine according to claim 2, wherein a ballast tank for storing water is provided inside the projecting portion.