JPH04194222A - Open shield construction method - Google Patents

Abstract

PURPOSE:To keep an underground structure horizontally and join it with an existing structure in an open shield construction method by arranging bearing members compressively deforming at load over a prescribed value in the tail part of a shield machine, and suspending down an underground structure on the members. CONSTITUTION:Propulsion jacks 2 are provided in a shield machine 1 opening the front and rear ends and the upper face, drilling is performed from the front face or the upper face of the front part, and the shield machine 1 is advanced with the propulsion jacks 2 supported by reaction of a succeeding existing structure. Next, a new underground structure 4 is suspended down from the upper face of a tail part 1d, positioned on the frontmost line of the existing structure 4, and the shield machine is propelled by repeating the similar process. Bearing members 11 arranged on a bottom plate 1c are made of hard rubber and the like, and provided with hollow parts 11a so as to easily deform. When the bottom plate 1c is inclined, they are deformed due to load, correcting portion of direction of the shield machine 1 is absorbed to join so as not to generate inclination on the underground structure, and execution accuracy is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an open shield construction method for constructing underground structures such as underground passages for water supply and sewage systems, public drains, telegraph and telephone lines, etc. in urban areas.

[Conventional technology]

The open shield construction method is a highly rational construction method that takes advantage of the advantages of the cut-and-cover construction method (open construction method) and the shield construction method.

Its outline is shown in FIGS. 5 to 7. In the figure, 1 is an open shield machine, and this is left and right side wall plates 1a.

It is a U-shaped shield machine consisting of 1b and a bottom plate IC that connects them, with openings on the front and rear end surfaces and the top surface.

The open shield machine 1 has propulsion jacks 2 disposed inside the side wall plates 1a and Ib, arranged vertically in the rear direction. 3 in the figure indicates a partition wall provided within the shield machine 1.

Although not shown, this shield machine 1 is installed in the starting shaft, and earth and sand in front of the starting shaft is excavated and discharged from the front or top opening of the shield machine 1.

Then, the propulsion jack 2 of the shield machine 1 is extended, and the reaction force is taken by the reaction wall in the launch shaft to advance the shield machine 1.
A first underground structure 4 made of a concrete box or the like is suspended from above and set behind the propulsion jack 2 which is retracted within the tail part ld of the shield machine 1.

Next, earth and sand are similarly excavated and removed from the front or upper surface of the shield machine 1 using an excavating means 9 such as a shovel, auger, or a packet, and the shield machine 1 is advanced to remove the first underground structure 4. First, the second underground structure 4 is suspended.

Thereafter, the same process of digging and setting 40 underground structures is repeated to sequentially bury the underground structures 4 in the ground in columns, backfill 5 is applied to the rear underground structures 4, and the open shield machine 1 reaches the reaching shaft, it is removed and the construction is completed.

8 in the figure is a pressed square timber framed at four corners, and the underground structure 4
After suspending, the push rod 8 is also placed at the front end of the underground structure 4, so that the reaction force of the propulsion jack 20 is uniformly obtained on the entire front end surface of the underground structure 4. It is something.

In the open shield construction method using the oven shield machine 1 as described above, the underground structure 4 is suspended on the support member 10 placed on the bottom plate IC of the tail part of the shield machine, and then Grout material 6 is filled under the bottom and side parts of the underground structure 4 within this tail portion Id, and after waiting for this grout material 6 to harden, it is left underground as the shield machine 1 moves forward. .

Furthermore, secondary grout 6' is applied further outside of the grout material 6 on the sides of the underground structure 40 remaining underground in this way.

The support member 10 is used to ensure a gap so that the grout 6 can sufficiently wrap under the bottom of the underground structure 4, and to keep the underground structure 4 as planned even if the shield machine 1 pitches or rolls when moving forward. This material serves as a height adjustment material to ensure clearance for laying the underground structure, and is made of blocks made of mortar, wood, steel, etc. It is located in

Then, the support member 10 is filled with the grout material 6 and buried therein, and is left underground together with the underground structure 4.

(Problem to be Solved by the Invention) However, since the supporting member 10 is made of a relatively rigid material as described above, when the shield machine 1 performs pitching correction in the upward and downward directions when moving forward, as shown in FIG. The underground structure 4 also moves in the same way, and the connection between the existing underground structure 4 and the newly suspended underground structure 4 does not fit well (
This causes the inconvenience of becoming

An object of the present invention is to eliminate the disadvantages of the conventional example, and to enable the supporting member to absorb the direction correction of the shielding machine through its deformation, allowing smooth connection between underground structures and improving construction accuracy. Our goal is to provide an open shield construction method.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a propulsion jack in a shield machine with openings at the front and rear ends and the top surface, excavates from the front surface or the top surface of the front part of the shield machine, and applies reaction force to existing underground structures such as a following box. Then, the shield machine is moved forward using the propulsion jack, and as the shield machine moves forward, a new underground structure is lowered from the upper surface of the tail part of the shield machine and placed in the front row of the existing underground structure, and the same process is repeated. In the open shield construction method in which a shield machine is used to excavate, the gist of the shield machine is to place a support member in its tail that compresses and deforms when a certain load is exceeded, and to suspend the underground structure onto this support member. It is.

[Effect]

According to the present invention, when the shield machine moves forward tilting upward or downward for direction correction, a load is applied to the support member that is not present during normal horizontal movement. At this time, the support member is compressively deformed by the load and absorbs the direction correction of the shield machine, so the underground structure above it does not tilt, and the underground structure maintains a horizontal level. Can be successfully connected to existing underground structures.

〔Example〕 Embodiments of the present invention will be described in detail below with reference to the drawings.

Fig. 1 is a vertical side view showing one embodiment of the open shield construction method of the present invention, and Fig. 2 is a perspective view of the main parts of the same. are given the same reference numerals.

The construction method of the present invention and the open shield construction method as a whole are generally the same as the conventional example.

That is, a U-shaped open shield machine 1 consisting of left and right side wall plates 1a, lb and a bottom plate IC connecting them, with openings at the front and rear end surfaces and the top surface is used, and this shield machine 1 is installed in the starting shaft. The earth and sand in front of the starting shaft is excavated and discharged from the front or top opening of the shield machine 1. Then, the propulsion jack 2 of the shield machine 1 is extended to take a reaction force to the reaction wall in the launch shaft, and the shield machine 1 is advanced, and the first underground structure 4 made of a concrete box or the like is suspended from above. Lower it and set it behind the propulsion jack 2, which has been retracted within the tail section 1d of the shield machine 1.

Next, earth and sand are similarly excavated from the front or upper surface of the shielding machine 1 using an excavating means 9 such as a shovel, an auger, or a bucket, and the earth is discharged, and the shielding machine 1 is advanced, and the first underground structure 4 is removed. First, the second underground structure 4 is suspended.

Thereafter, the same excavation and setting process of the underground structures 4 is repeated to sequentially bury the underground structures 4 in the ground in columns, backfill 5 is applied on the rear underground structures 4, and open shield Once Machine 1 reaches the destination shaft, it will be removed and the construction will be completed.

The underground structure 4 is the bottom plate IC of the tail part of the shield machine.
A support member 11 is disposed on top and the support member 11 is suspended on top of the support member 11. In the present invention, this support member 11 is compressively deformed when a certain load is exceeded.

The material of the support member 11 is hard rubber (SBR70
' ~ 80°) is optimal, and its shape is as shown in FIGS. 2 and 3 in order to easily obtain deformation.
It is a block body with a.

As shown in Fig. 3, this support member 11 does not deform simply by placing the underground structure 4 on it, but compressively deforms when external forces are applied to it. Set the intensity to .

Further, as long as the support member 11 has such a characteristic that it compressively deforms when a certain load is exceeded, it is possible to use an elastic member such as a spring or a synthetic resin having plasticity.

After suspending the underground structure 4 onto the support member 11, grout material 6 is filled under the bottom and side portions of the underground structure 4 in the tail portion ld of the shield machine 1, and the grout material 6 is filled with grout material 6. After it hardens, it is left underground by the advance of the shield machine.

Furthermore, secondary grout 6' is applied to the outer side of the grout material 6 on the sides of the underground structure 4 remaining underground in this way.

In this way, as shown in FIG. 4, when the shield machine 1 moves forward while tilting upward or downward for direction correction, a load is applied to the support member 11 that is not present during normal horizontal movement. At this time, the support member 11 is compressively deformed by the load caused by the tilting of the bottom plate IC of the shield machine 1 and absorbs the direction correction of the shield machine, so that the underground structure 4 above it does not tilt. , the underground structure 4 can maintain its horizontal level and be successfully connected to the existing underground structure 4.

The existing underground structure 4 and the new underground structure 4 are tightly connected using a PC steel rod or the like.

Note that when the shield machine 1 moves forward at a normal horizontal level, the support member 11 is not deformed because only the load of the underground structure 4 is applied and no special load is applied to the support member 11.

〔Effect of the invention〕

As described above, in the open shield construction method of the present invention, even if the shield machine is tilted up or down due to direction correction, the underground structures suspended from the tail of the shield machine remain at a horizontal level, and as a result, the joints between the underground structures are can be done smoothly and improve construction accuracy.

[Brief explanation of the drawing]

Fig. 1 is a vertical side view showing one embodiment of the open shield construction method of the present invention, Fig. 2 is a perspective view of the main parts of the same, Fig. 3 is a longitudinal front view of the support member used in the construction method of the present invention, and Fig. 4 The figure is an explanatory diagram showing the state when moving forward, Figure 5 is a vertical side view showing the conventional open shield construction method, Figure 6 is a vertical rear view of the same as above,
FIG. 7 is a plan view of the same as the above, and FIG. 8 is an explanatory view showing the state of the same when moving forward. 1... Open shield machine Ia, lb... Side wall plate 1c... Bottom plate 1d...
Tail part 2... Propulsion jack 3... Bulkhead
4... Underground structure 5... Backfilling 6.6'... Grout material 8... Push angle material 9... Excavation means 10.11... Supporting member 11a... Hollow part

Claims (1)

[Claims] A propulsion jack is installed inside the shield machine with the front and rear ends and top open, excavation is made from the front or top of the front part of the shield machine, and the propulsion jack is used to advance the shield machine using the reaction force of the existing underground structure such as the following box. In the open shield construction method, a new underground structure is suspended from the upper surface of the tail of the shield machine during this advance, placed in the front row of the existing underground structure, and the same process is repeated to allow the shield machine to dig. The shield machine is an open shield construction method characterized by placing a support member in the tail that compresses and deforms when a certain load is exceeded, and suspending the underground structure onto this support member.