JPH07119386A - Open shield method and open shield machine - Google Patents

Abstract

PURPOSE:To stabilize the ground in the case of driving by overhanging one side each of end of each of flexible tie plates outward to the front ends of both right and left side wall boards of an open shield machine to provide. CONSTITUTION:In a shield machine 1 with opened front, rear and upper surfaces consisting of both right and left side wall boards 1a and a bottom plate 1b connected to them, driving jacks 3 are arranged to the centers of the side wall boards la or near the rear ends of them. Flexible tie plates 14 such as rubber plates, etc. are so provided along the vertical direction of the front ends of both right and left side wall boards la that one side end of each of the flexible tie plates is overhung to the outside. The open shield machine 1 with such flexible tie plates is set in a starting tunnel, and the driving jacks are expanded to start the shield machine. Mounting sides of the flexible tie plates 14 to the side wall boards la and one side end on the opposite side are brought into contact with the excavated surface of a bedrock and are pushed against it to advance in a state to curve 1b. The flexible tie plates 14 separate the front end part of the open shield machine 1 from the rear part thereof between the side wall boards 1a and bedrock, and the entering of the collapsed earth into an opening of the front end is prevented in th case of advancement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an open shield construction method and an open shield machine for constructing an underground structure such as an underground passage for laying water and sewage systems, common ditches, telegraphs and telephones in urban areas.

[0002]

2. Description of the Related Art The open shield construction method is a highly rational construction method that takes advantage of the advantages of the open cut construction method (open cut construction method) and the shield construction method. The outline is shown in FIGS. 3 to 6, in which 1 is an open shield machine, which is a shield having a front surface, a rear surface and an upper surface which are composed of left and right side wall plates 1a and a bottom plate 1b connected to these side wall plates 1a. In the machine, the propulsion jacks 3 are arranged vertically side by side near the center or near the rear end of the side wall plate 1a.

As shown in FIG. 3, the open shield machine 1 is installed in the launch pit 8 and the propulsion jack 3 of the shield machine 1 is extended to apply a reaction force to the reaction wall 9 in the launch pit to shield the shield. The machine 1 is moved forward, the first concrete box 4 forming the underground structure is suspended from above, and is set behind the propulsion jack 3 compressed in the tail portion of the shield machine 1. In the figure, reference numeral 10 denotes a strut, which is arranged between the propulsion jack 3 and the reaction force wall 9 for appropriately adjusting the gap. Further, the start pit 8 is composed of a retaining wall, and in order to start the open shield machine 1, a part of this retaining wall is cut into a mirror.

Then, the excavator 6 such as a shovel excavates earth and sand from the front surface or the top surface of the open shield machine 1 and discharges it. Simultaneously with or after this soil discharging step, the propulsion jack 3 is extended to advance the shield machine 1. In the case of this advancing process, a pushing angle 7 made of a frame body made of box steel or shaped steel is arranged in front of the concrete box 4. Then, before the first concrete box 4, the second concrete box 4 is suspended in the tail portion of the shield machine 1. Hereinafter, the same soil discharging process, advancing process, and setting process of the concrete box 4 are appropriately repeated to sequentially leave the concrete box 4 in the ground in parallel with the advancing of the open shield machine 1, and further to this concrete box. Backfill 5 is applied to the upper surface of 4, and pavement 12 is applied to the surface.

In this way, when the open shield machine 1 reaches the reaching pit 13, it is removed and the construction is completed.

[0006]

In such an open shield construction method, when the ground is a gravel layer or a gravel layer, excavation with an excavator 6 such as a shovel causes the ground to collapse easily, resulting in excessive dug. As a result, the borehole wall is likely to collapse. The gap between the left and right side wall plates 1a of the open shield machine 1 and the hole wall is filled with the collapsed gravel.

As a result, the gravel that has collapsed during the forward movement of the open shield machine 1 is dragged and wraps around into the tip opening of the open shield machine 1 to induce a larger collapse.

In particular, when performing a curve construction, the strokes of the propulsion jacks 3 arranged on the left and right inside the open shield machine 1 are made different and the open shield machine 1 is bent and advanced, and the extent of the collapse occurs. growing.

The object of the present invention is to solve the disadvantages of the above-mentioned conventional example and to open the open shield construction method and the open shield method capable of easily maintaining the stability of the ground even when the open shield machine excavates the ground such as the gravel layer which is likely to collapse To provide a shield machine.

[0010]

In order to achieve the above-mentioned object, the present invention has a propulsion jack provided inside the left and right side wall plates,
A step of excavating and discharging earth and sand in front of the front or upper surface opening of the open shield machine having the front, rear surface and upper surface opened,
The process of extending the propulsion jack and making the concrete box a reaction force to move the shield machine forward, and the process of suspending and setting a new concrete box from above behind the propulsion jack that has been compressed in the tail part of the shield machine. In the open shield method of sequentially burying concrete boxes in a vertical row by repeating the steps and, along the vertical direction of the left and right side wall plates of the open shield machine, one side end of the flexible band plate is Advancing the open shield machine while bending the flexible strip in the width direction by pressing one side end of the flexible strip to the ground surface so as to project outward, and
The gist of the present invention is to attach a curved metal strip having a U-shaped or L-shaped cross section as a backing plate to the flexible strip.

[0011]

According to the present invention as set forth in claims 1 and 2, the flexible strips provided at the tips of the left and right side wall plates of the open shield machine are bent in the width direction by pressing one side end against the ground surface. In the state, it becomes a partition that divides the tip of the open shield machine and its rear between the open shield machine and the ground,
This flexible strip prevents the gravel that has collapsed during the forward movement of the open shield machine from being dragged around the tip opening of the open shield machine.

The flexible strip is capable of exerting a function as a partition without being continuously separated from the ground surface even when the open shield machine is stopped or when it is advanced by a curve due to the pressing action on the ground surface.

According to the third aspect of the present invention, in addition to the above-mentioned action, the flexible metal strip that receives a pressing force when the open shield machine advances is extremely deformed and damaged. It can be prevented by hitting.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a plan view showing an embodiment of an open shield construction method and an open shield machine of the present invention, and FIG. 2 is a plan view of a main part of the same.

The basic structure of the open shield machine 1 of the present invention is the same as that described in the above-mentioned conventional example. This is the left and right side wall plates 1a and the bottom plate 1b connected to these side wall plates 1a.
In a shield machine having front, rear, and upper surfaces consisting of and, the propulsion jacks 3 are arranged vertically in the rear direction near the center or the rear end of the side wall plate 1a.

At the tips of the left and right side wall plates 1a of the open shield machine 1, along the vertical direction of the side wall plates 1a, a flexible band plate 14 made of a rubber plate or a synthetic resin plate is placed with one side end outward. It is provided so as to project.

To attach the flexible strip 14 to the tip of the side wall plate 1a, the backing plate 15 has a U-shaped section or L-shape.
A curved metal strip having a character shape is additionally provided, and one side end of the flexible strip 14 is sandwiched between the straight extending piece of the curved metal strip and the abutting plate 16 made of a normal flat plate, and the side wall plate 1a Bolted to the inner tip.

As another embodiment, although not shown, it is conceivable that the flexible strip plate 14, the backing plate 15 and the like may be bolted to the outer end of the side wall plate 1a.

In this way, the open shield machine 1 with the flexible strip 14 is set in the starting pit 8, and the propulsion jack 3 is extended to start from the starting pit 8.

One end of the flexible strip 14 opposite to the side where it is attached to the side wall plate 1a comes into contact with the excavated ground surface and is pressed against it to be curved in the width direction, and open in this state. The shield machine 1 moves forward.

As a result, the flexible strip plate 14 serves as a partition between the side wall plate 1a of the open shield machine 1 and the ground to partition the front end portion of the open shield machine 1 and its rear side. 14 prevents the gravel that has collapsed when the open shield machine 1 moves forward from being dragged around the open end of the open shield machine 1.

The flexible strip 14 does not separate from the ground surface even when the open shield machine 1 is stopped during the installation process of the concrete box 4, the excavation / excavation process, etc., and acts as a partition. Can be demonstrated.

Further, since the width of the flexible strip 14 can be changed by changing the bending degree thereof, even when the distance between the side wall plate 1a and the natural ground is changed during the forward movement by a curve, the flexible strip 14 is continuously separated from the natural ground surface. There is no such thing.

Further, even if the flexible strip 14 is strongly pressed and the degree of deformation is extremely large, the backing plate 15 is provided so that it serves as a reinforcement and prevents the flexible strip 14 from being damaged. You can

[0025]

As described above, the open shield construction method and the open shield machine of the present invention can easily maintain the stability of the ground even when the open shield machine excavates the ground such as the gravel layer which is likely to collapse. It is a thing.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of an open shield construction method and an open shield machine of the present invention.

FIG. 2 is a plan view of a main part showing an embodiment of an open shield construction method and an open shield machine of the present invention.

FIG. 3 is a vertical sectional side view of a first step showing an outline of an open shield construction method.

FIG. 4 is a vertical sectional side view of a second step showing an outline of the open shield construction method.

FIG. 5 is a vertical sectional side view of a third step showing an outline of the open shield construction method.

FIG. 6 is a vertical sectional side view of a fourth step showing an outline of the open shield construction method.

[Explanation of symbols]

 1 ... Open shield machine 1a ... Side wall plate 1b ... Bottom plate 3 ... Propulsion jack 4 ... Concrete box 5 ... Backfill 6 ... Excavator 7 ... Push angle 8 ... Start pit 9 ... Reaction wall 10 ... Strut 12 ... Pavement 13 ... Arrival Pit 14 ... Flexible strip 15 ... Back plate 16 ... Plate

Claims (3)

[Claims] 1. A process of arranging propulsion jacks inside left and right side wall plates, excavating and discharging earth and sand from the front or top opening of an open shield machine having front, rear and top openings, and extending the propulsion jack. Repeat the process of moving the shield machine forward by using the concrete box as a reaction force and the step of suspending and setting a new concrete box from the top behind the propulsion jack that was contracted in the tail part of the shield machine. In the open shield construction method of sequentially burying concrete boxes in vertical columns, one side end of the flexible band plate extends outward at the tip of the left and right side wall plates of the open shield machine along the vertical direction of the side wall plates. And an open shield machine that advances the open shield machine while pressing one side end of the flexible strip plate against the ground surface to bend the flexible strip plate in the width direction. Ludo construction method. 2. A propulsion jack is disposed inside the left and right side wall plates, and the front, rear, and upper surfaces of the left and right side wall plates of the open shield machine are opened at their front end portions along the vertical direction of the side wall plates.
An open shield machine characterized in that a flexible strip is provided so that one side end thereof projects outward. 3. The open shield machine according to claim 2, wherein a curved metal strip having a U-shaped or L-shaped cross section is attached to the flexible strip as a backing plate.