JP3250709B2 - Open shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art The open shield method is a rational method utilizing the advantages of the open cutting method (open cut method) and the shield method. FIG. 9 to FIG. 12 schematically show an open shield machine 1 having a front, rear, and upper surface opened with left and right side walls 2 and a bottom plate 3 connected to these side walls 2. Machine.

[0003] In the drawing, the open shield machine 1 is divided into a front portion 1a and a tail portion 1b so as to be able to cope with a curve construction, and ends thereof are loosely fitted to each other.

[0004] The open shield machine 1 has a front part 1a.
In this embodiment, the tips of the side wall plate 2 and the bottom plate 3 are formed as cutting holes 2, and the propulsion jacks 4 are arranged vertically inside the side wall plate 2 at both the front part 1a and the tail part 1b toward the rear. In addition, regarding the front part 1a, the partition wall 5 divides into a first half excavation part and a second half propulsion part by the propulsion jack 4.

[0005] As shown in FIG. 9, the open shield machine 1 is installed in the starting pit 8, the propulsion jack 4 of the shield machine 1 is extended, and a reaction force is applied to the reaction wall 6 in the starting pit 8. To advance the front part 1a and the tail part 1b one by one,
The first concrete box 7 forming the underground structure is suspended from above and set behind the propulsion jack 4 which has been contracted in the tail portion 1b of the shield machine 1. In the drawing, reference numeral 10 denotes a strut, which is disposed between the propulsion jack 3 and the reaction wall 6 for adjusting the interval as appropriate. The starting pit 8 is formed of a retaining wall, and the retaining wall is partially mirror-cut to start the open shield machine 1. However, if necessary, a ground improvement 11 May be given.

Next, earth and sand are excavated and discharged from the front or upper surface of the front portion 1a of the open shield machine 1 by an excavator 9 such as a shovel. Simultaneously with or after this earth removal step, the propulsion jack 4 is extended to advance the front part 1a and the tail part 1b sequentially and individually.

[0007] The first concrete box 7
Before the second concrete box 7 is suspended in the tail part 1b of the shield machine 1.

[0008] As shown in FIGS. 10 and 11, the same earth removal process, advancement process, and setting process of the concrete box 7 are repeated as necessary, and the concrete box 7 is sequentially moved with the advance of the open shield machine 1. The concrete box 7 is buried in the ground in a row and the upper surface of the concrete box 7 is buried.

In this manner, as shown in FIG. 12, when the open shield machine 1 reaches the reaching pit 12, it is removed and the construction is completed.

In the open shield method, when the aquifer is used for rehabilitation of a river or the like, the groundwater level is high, and there is a possibility that the groundwater will be flooded during the construction. Such inundation can be prevented by the partition wall 5 at the excavated portion at the front end of the front portion 1a, but it is difficult to prevent the flooded portion between the front portion 1a and the tail portion 1b by mutual play.
Water will accumulate at the places where the concrete box 7 is installed and at the place where the concrete box 7 is arranged, which hinders the work.

As a countermeasure, it is possible to suppress inundation by performing ground improvement such as injection of a chemical solution or a freezing method as described above at all locations where construction is to be performed, and to allow infiltration into the open shield machine. Are being released as quickly as possible.

[0012]

However, the conventional method of improving the ground to suppress inundation into the open shield machine requires a separate ground improvement work, which leads to a rise in construction costs and a prolonged construction period. . On the other hand, the method of extracting water that has invaded the inside of the open shield machine is not sufficient because water cannot be completely removed depending on the capacity of the pump.

It is an object of the present invention to provide an open shield method capable of solving the inconvenience of the conventional example and easily and surely suppressing infiltration of groundwater into an open shield machine.

[0014]

In order to achieve the above object, according to the present invention, first, a propulsion jack is disposed inside the left and right side wall plates, and the front, rear and upper surfaces are opened, and the front part is connected to the front part. The process of excavating and discharging earth and sand in front of the front or top opening of the front part of the open shield machine where the end part is loosely fitted with the tail part, and the propulsion jack is extended to react the concrete box The shield machine forward, and the process of suspending and setting a new concrete box from above at the rear of the propelled jack shrunk in the tail part of the shield machine, and repeating the process as necessary to sequentially cascade the concrete boxes In the buried open shield method, the front part of the open shield machine is divided into an excavation part in the first half of the bulkhead and a propulsion part by the propulsion jack in the latter half, and the fuselage of the body behind the bulkhead. On the other hand, a permeation hole provided with a means for preventing sediment inflow by mesh or slit is provided, and a water supply pipe for forced water supply by a pump is connected to the permeation hole, and the infiltrated water from this permeation hole is sucked and forcibly discharged. The main point is to lower the groundwater level outside the open shield machine.

Second, the water-permeable holes are provided in the lower part of the left and right side wall plates, or are provided in the bottom plate. Third, the water pipe is set up along the inside of the left and right side wall plates and guided to the ground. Alternatively, the gist of the present invention is to guide the vehicle to a start pit in an open shield machine and through a concrete box that is cascaded.

[0016]

According to the first aspect of the present invention, a water permeable hole is provided below the body of the open shield machine by the open shield method, and infiltration water is discharged from the water permeable hole to reduce the groundwater level outside the open shield machine. By lowering, the amount of groundwater that intrudes into the open shield machine from other than the water permeation hole can be reduced as much as possible, so that work in the open shield machine can be prevented. In addition, unlike the installation of well points outside the open shield machine, drainage from the open shield machine itself can be performed, eliminating the need for installation of equipment and other equipment, and drainage points as the open shield machine progresses. Can be easily moved.

Further, a water supply pipe for forcibly sending water by a pump is connected to the water permeation hole, and the water entering through the water permeation hole is sucked and forcibly discharged by utilizing the suction force of the pump, so that the outside of the open shield machine is removed. It is possible to more surely lower the groundwater level of the river.

In addition to this, as an open shield machine, groundwater is taken into the open shield machine from outside the lower portion of the left and right side wall plates, and the infiltrated water is discharged to lower the groundwater level outside the open shield machine. it can. At this time, it is possible to prevent earth and sand from flowing together with the groundwater by means of earth and sand inflow prevention means using a mesh or a slit.

According to the second aspect of the present invention, groundwater is taken into the open shield machine from outside the lower portions of the left and right side wall plates. According to the third aspect of the present invention, groundwater is taken from outside the bottom plate portion. Groundwater is taken into the open shield machine, and the groundwater level outside the open shield machine can be lowered.

According to the fourth aspect of the present invention, wastewater can be treated with a water pipe as short as possible.
According to the present invention described above, in the case of construction in a narrow place where there is not enough site on the left and right sides of the open shield machine, it is possible to cope with the problem by performing drainage treatment at the start pit.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the first embodiment of the open shield method of the present invention.
FIG. 2 is a longitudinal sectional front view showing the embodiment, and FIG. 2 is a longitudinal sectional side view of the same. The same reference numerals are given to the same components as those in FIGS.

The general outline of the open shield method is as described with reference to FIGS.
The basic configuration of the open shield machine 1 is also a shield machine having left and right side walls 2 and a bottom plate 3 connected to these side walls 2 and having front, rear and upper surfaces opened.

The open shield machine 1 is divided into a front part 1a and a tail part 1b so as to be able to cope with a curve construction, and ends thereof are loosely fitted to each other.

Further, the open shield machine 1 forms the front end of the side wall plate 2 and the bottom plate 3 at the front portion 1a as cutting edges, and propells the inside of the side wall plate 2 with both the front portion 1a and the tail portion 1b. The jacks 4 are arranged side by side vertically toward the rear. In addition, regarding the front part 1a, the partition wall 5 causes the excavation part in the first half and the propulsion jack 4 in the second half.
And a propulsion unit.

In the present invention, a water permeable hole 13 is formed below the left and right side walls 2 of the open shield machine 1. The number and size of the water-permeable holes 13 may be arbitrary, but are provided at the front part 1a behind the partition wall 5.

A mesh 14 is provided in the water permeation hole 13 as means for preventing sediment inflow. Instead of the mesh 14, a slit may be formed by a lattice to serve as means for preventing sediment inflow.

Further, a joint 15 is provided from the periphery of the water permeable hole 13 to the inside.
The end of a water pipe 16 is connected to the joint 15, and the water pipe 16 is raised along the inside of the left and right side wall plates 2 and guided to the ground. In addition, a pump 17 was provided in the middle of the water pipe 16.

The open shield method using the open shield machine 1 provided with the water permeation holes 13 is as described above. As shown in FIG. Then, the propulsion jack 4 of the shield machine 1 is extended and a reaction force is applied to the reaction wall 6 in the starting pit 8 so that the front part 1a and the tail part 1b are sequentially and individually advanced to form an underground structure. The first concrete box 7 is suspended from above and set behind the propulsion jack 4 which has been contracted in the tail portion 1b of the shield machine 1.

Next, earth and sand are excavated and discharged from the front or upper surface of the front portion 1a of the open shield machine 1 by an excavator 9 such as a shovel. Simultaneously with or after this earth removal step, the propulsion jack 4 is extended to advance the front part 1a and the tail part 1b sequentially and individually.

Then, the first concrete box 7
Before the second concrete box 7 is suspended in the tail part 1b of the shield machine 1.

As shown in FIG. 10 and FIG. 11, the same earth removal process, advancement process, and setting process of the concrete box 7 are repeated as appropriate, and the concrete box 7 is sequentially moved with the advance of the open shield machine 1. It is left in the ground in a column, and the upper surface of this concrete box 7 is backfilled. As shown in FIG. 12, when the open shield machine 1 reaches the reaching pit 12, it is removed and the construction is completed. I do.

In such a process, if the pump 17 is driven to discharge the infiltrated water from the water permeation hole 13 to the ground via the water pipe 16, the underground water level outside the open shield machine 1 is indicated by a chain line. Can be lowered.

As a result, the amount of underground water entering the open shield machine 1 from other than the water permeation holes 13, particularly from the mutual loose fit between the front part 1 a and the tail part 1 b, can be reduced as much as possible. Can be prevented.

FIGS. 3 and 4 show a second embodiment of the present invention. A water pipe 16 is connected to a start shaft 8 (see FIG. 9 and subsequent figures) through an open shield machine 1 and a concrete box 7 arranged in tandem. I decided to lead.

Further, as a third embodiment, as shown in FIGS. 5 and 6, the water permeable holes 13 may be provided in the bottom plate 3 of the open shield machine 1. Other permeable holes
The number and size of the thirteen may be arbitrary, for example, the front part 1
a to be provided behind the partition wall 5, and
The mesh 14 is provided as a means to prevent sediment inflow,
It is the same as in the first embodiment that a slit may be formed by a lattice instead of the mesh 14 to provide a means for preventing inflow of earth and sand.

Furthermore, the joint 15
The end of a water pipe 16 is connected to the joint 15, and the water pipe 16 is raised along the inside of the left and right side wall plates 2 and guided to the ground. Further, the point that a pump 17 is provided in the middle of the water pipe 16 is the same as that of the first embodiment.

The pump 17 is driven to drive water through holes provided in the bottom plate 3.
Even if infiltration water from 13 is discharged to the ground via water pipe 16,
The underground water level outside the open shield machine 1 can be lowered like a chain line.

As shown in FIGS. 7 and 8, the water pipe 16 may be guided to the starting pit 8 in the open shield machine 1 and through the parallel concrete boxes 7.

[0039]

As described above, the open shield method according to the present invention can easily and surely prevent infiltration of groundwater into the open shield machine, and as a result, does not hinder the work inside the open shield machine. Is what you can do.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing a first embodiment of the open shield method according to the present invention.

FIG. 2 is a vertical sectional side view showing a first embodiment of the open shield method according to the present invention.

FIG. 3 is a vertical sectional front view showing a second embodiment of the open shield method according to the present invention.

FIG. 4 is a longitudinal sectional side view showing a second embodiment of the open shield method according to the present invention.

FIG. 5 is a vertical sectional front view showing a third embodiment of the open shield method of the present invention.

FIG. 6 is a vertical sectional side view showing a third embodiment of the open shield method according to the present invention.

FIG. 7 is a longitudinal sectional front view showing a fourth embodiment of the open shield method according to the present invention.

FIG. 8 is a vertical sectional side view showing a fourth embodiment of the open shield method of the present invention.

FIG. 9 is a vertical sectional side view of a first step showing an outline of the open shield method.

FIG. 10 is a vertical sectional side view of a second step showing an outline of the open shield method.

FIG. 11 is a vertical sectional side view of a third step showing an outline of the open shield method.

FIG. 12 is a vertical sectional side view of a fourth step showing an outline of the open shield method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Open shield machine 1a ... Front part 1b ... Tail part 2 ... Side wall plate 3 ... Bottom plate 4 ... Propulsion jack 5 ... Partition wall 6 ... Reaction wall 7 ... Concrete box 8 ... Starting pit 9 ... Excavator 10 ... Strut 11 ... Soil improvement 12 ... Arrival pit 13 ... Permeate hole 14 ... Mesh 15 ... Fitting 16 ... Water pipe 17 ... Pump

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-39521 (JP, A) JP-A-58-156794 (JP, U) JP-A-48-10986 (JP, Y1) (58) Field (Int.Cl. ⁷ , DB name) E21D 9/06 331 E21D 9/06 301 E02D 17/08

Claims (5)

(57) [Claims] 1. An open shield machine in which propulsion jacks are arranged inside left and right side wall plates, the front, rear and upper surfaces are opened, and a front part and a tail part are divided, and ends are loosely fitted to each other. Excavating and discharging earth and sand in front of the front or top opening of the front part, extending the propulsion jack to make the concrete box a reaction force and moving the shield machine forward, and shrinking in the tail part of the shield machine The process of suspending and setting a new concrete box from the top behind the propulsion jack is repeated as appropriate, and the concrete box is sequentially buried in a row.In the open shield method, the front part of the open shield machine is in the first half of the bulkhead. It is divided into an excavation part and a propulsion part with a propulsion jack in the latter half, and is equipped with a means of preventing sediment inflow by mesh or slit below the fuselage behind the bulkhead A permeation hole is provided, and a water pipe for forced water supply by a pump is connected to the permeation hole, and the infiltration water from this permeation hole is sucked and forcibly discharged to lower the groundwater level outside the open shield machine. Open shield method. 2. The open shield method according to claim 1, wherein the water permeable holes are provided in lower portions of the left and right side wall plates. 3. The open shield method according to claim 1, wherein the water permeable holes are provided in the bottom plate. 4. The open shield method according to claim 1, wherein the water pipe is set up along the inside of the left and right side wall plates and guided to the ground. 5. The open shield method according to claim 1, wherein the water pipe is guided to a starting pit through a concrete box inside the open shield machine and in tandem.