JP3715618B2 - Simple shaft used in the open shield method and its construction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a simple shaft used in an open shield construction method for constructing underground structures such as water and sewage systems and underground passages in an urban area, and a construction method thereof.
[0002]
[Prior art]
The open shield method is a rational method that takes advantage of the open cut method (open cut method) and the shield method, and the outline of the open shield machine 1 used in this open shield method is as shown in FIG. The front, rear and top surfaces of the plate 1a and the bottom plate 1b connected to these side wall plates 1a are opened, the tips of the side wall plate 1a and the bottom plate 1b are formed as blade edges 11, and the center of the side wall plate 1a or Near the rear end, the shield jacks 2 are arranged side by side facing up and down. In the figure, 3 indicates a partition wall.
[0003]
The open shield method to be constructed using the open shield machine 1 is not shown in the figure, but the open shield machine 1 is installed in the start pit, the shield jack 2 of the open shield machine 1 is extended, and the inside of the start mine is The open shield machine 1 was moved forward by taking the reaction force against the reaction wall, and the first concrete box 4 forming the underground structure was suspended from above and shrunk in the tail portion 1c of the open shield machine 1. Set behind the shield jack 2. A strut is disposed between the shield jack 2 and the reaction wall to adjust the distance appropriately.
[0004]
In addition, the start pit is made up of a retaining wall, and in order to start the open shield machine 1, a part of this retaining wall is mirror-cut, but if necessary, the ground is improved in the front part of the starting pit by chemical injection or the like. Sometimes it is left.
[0005]
Excavator 9 such as an excavator excavates and removes soil from the front or upper surface of open shield machine 1. Simultaneously with or after this earth removal step, the shield jack 2 is extended to advance the open shield machine 1. In the case of this advancement process, a pushing angle 8 made of a frame made of box steel or mold steel is arranged in front of the concrete box 4, and the open shield machine 1 receives a reaction force from the concrete box 4 set rearward. Take.
[0006]
Then, the second concrete box 4 is suspended in the tail portion 1 c of the open shield machine 1 in front of the first concrete box 4. Thereafter, the same soil removal process, advance process, and setting process of the concrete box 4 are repeated as appropriate, and the concrete boxes 4 are sequentially left in the ground as the open shield machine 1 moves forward. Put backfill 5 on the upper surface of 4.
[0007]
When the concrete box 4 is suspended in the tail part 1c of the open shield machine 1, a height adjusting material 7 such as a concrete block is disposed under the concrete box 4, and the inside of the tail part 1c. The grout material 6 is filled in the left and right and lower gaps of the concrete box 4.
[0008]
In this way, if the open shield machine 1 reaches the reaching mine, it is removed and the construction is completed.
[0009]
In such an open shield construction method, as described above, the concrete box 4 is left in the ground in a column as the open shield machine 1 advances, and the concrete box 4 is suspended in the tail portion 1c of the open shield machine 1. As the open shield machine 1 moves forward, it leaves the tail portion 1c and remains in the ground. The open shield machine 1 takes a reaction force on the concrete box 4 left in the ground in this way. Advance.
[0010]
The concrete box 4 is made of reinforced concrete and includes a left side plate 4a, a right side plate 4b, an upper floor plate 4c, and a lower floor plate 4d as shown in FIG.
[0011]
[Problems to be solved by the invention]
By the way, it is conceivable that the start pit is formed by a simple vertical shaft when the ground is stable. As shown in FIGS. 7 and 8, the simple vertical shaft first excavates a portion close to the ground surface and builds a first-stage earth retaining plate 12a around it, and cuts the first-stage earth retaining plate 12a between the opposing earth retaining plates 12a. After inserting the beam 13a, and further excavating the lower part, a second-stage earth retaining plate 12b is built around the new excavated portion, and the second-stage beam 13b is inserted between the opposing earth retaining plates 12b. Then, after further excavating the lower part, the third stage retaining plate 12c is built around the new excavated part, and the third stage cut beam 13c is inserted between the opposing retaining plates 12c. To do.
[0012]
However, in order to use such a simple shaft as a start shaft of the open shield machine 1, a large number of beams 13a to 13c exist in the forward direction of the open shield machine 1 and cross the start shaft. It is impossible to install the open shield machine 1 at the same time, and it has not been possible to use this as a starting pit in the conventional simple shaft.
[0013]
An object of the present invention is to provide a simple shaft that can be used as a start shaft of an open shield machine and can be easily constructed, and a method for constructing the same.
[0014]
[Means for Solving the Problems]
In order to achieve the above-described object, the present invention provides a construction method in which, firstly, while excavating the interior, the earth retaining plates are sequentially built in a plurality of stages from the upper stage to the lower stage, and a temporary beam is formed between the opposing earth retaining plates by a beam. The gist of the present invention is that after the support work is arranged, a rectangular frame-shaped support work made of a beam member is disposed between the opposing retaining plates, and the temporary support work is removed and constructed.
[0015]
Secondly, the gist of the support is composed of divided bodies that are divided into a plurality of stages in the vertical direction, and thirdly, a packing material is interposed between the support and the retaining plate.
[0016]
Fourthly, as a simple shaft, the gist is that a supporting work by a rectangular frame-shaped beam member is arranged between the retaining plates sequentially built in a plurality of stages from the upper stage to the lower stage.
[0017]
According to the first and fourth aspects of the present invention, since the support work is formed in a square frame shape arranged between the retaining plates, the open shield machine can advance in the frame support work. It can be used as an open shield machine start pit. In addition, the construction of such a simple shaft is to place a temporary support work with a cut beam as before, place a support work with a rectangular frame-shaped cut beam member, and then remove the temporary support work. Therefore, it can be easily constructed.
[0018]
According to the second aspect of the present invention, in addition to the above-described operation, the support work is configured by a divided body that is divided into a plurality of stages in the vertical direction, so that it is easy to build and construct the shaft in the shaft.
[0019]
According to this invention of Claim 3, in addition to the said effect | action, the space | interval between the earth retaining plates built in the multistage differs by each stage by interposing a packing material between a support work and a earth retaining plate. Even in such a case, a rectangular frame-shaped support can be arranged vertically between the retaining plates.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal front view of a state where an open shield machine 1 showing an embodiment of a simple shaft according to the present invention is installed, FIG. 2 is a plan view of the same, and the open shield machine 1 is divided into three in the front-rear direction as an example. Therefore, the propulsion jack is disposed on the tail portion 1c. The front portion 1d has a blade edge 11 at the tip, the middle portion 1e, and the tail portion 1c on which the concrete box 4 is suspended.
[0021]
The simple shaft of the present invention is used as a starting shaft of such an open shield machine 1, and is supported by a rectangular frame-shaped beam member between earth retaining plates 12a, 12b, and 12c that are sequentially built up and down in a plurality of stages. 14 were placed.
[0022]
In order to construct a simple shaft by installing the support 14, first, as shown in FIGS. 3 and 4, a portion close to the ground surface is excavated shallowly, and a first-stage earth retaining is formed around it. After the plate 12a is built, the first stage beam 13a is inserted as a temporary support between the opposing retaining plates 12a, and then the second stage is dug around the new excavated part The earth retaining plate 12b is built, the second stage beam 13b is inserted as a temporary support between the opposing earth retaining plates 12b, and then the lower stage is further excavated, and then the third stage around the new excavated part. The retaining plate 12c is built, and the third stage beam 13c is inserted as a temporary support between the opposing retaining plates 12c.
[0023]
As the earth retaining plates 12a to 12c go to the lower stage, the upper part of the lower stage is superposed inside the lower part of the upper stage, and the width between the opposing earth retaining plates 12a to 12c becomes narrower.
[0024]
After a plurality of temporary support works with small cut beams 13a to 13c are installed in this way, a support work 14 with a square frame-shaped cut beam member is disposed as shown in FIGS. The supporting structure 14 is constructed by placing a U-shaped beam member 14a between the retaining plates 12c, avoiding the place where the beams 13a to 13c are disposed, and then placing the beam members 14a between the retaining plates 12c. A middle beam member 14b is disposed on the member 14a. In this case, the middle beam member 14b is fixed to the earth retaining plate 12c by the positioning pin 15 together with the lower beam member 14a.
[0025]
In this case, since the middle earth retaining plate 12b is positioned outside the lower earth retaining plate 12c, a gap is generated between the middle beam member 14b and the middle earth retaining plate 12b. Interposes a wedge-shaped packing material 16.
[0026]
Next, a U-shaped uppermost beam member 14c formed in a U-shape is arranged on the middle beam member 14b, and is fixed to the earth retaining plate 12b together with the middle beam member 14b by a positioning pin 15. A packing material 16 is interposed in the gap between the uppermost beam member 14c and the retaining plate 12a.
[0027]
A square frame-shaped support member 14 is arranged by combining the beam members 14a to 14c divided into a plurality of parts in this way. In this state, if the temporary support work by the small cut beams 13a to 13c is removed while leaving the support work 14, a simple shaft is constructed.
[0028]
Then, as shown in FIGS. 1 and 2, the open shield machine 1 is assembled and installed inside the support work 14. Since the support work 14 has a square frame shape, a large space is formed inside thereof, and the assembly and installation of the open shield machine 1 can be performed here.
[0029]
【The invention's effect】
As described above, the simple shaft of the present invention and the construction method thereof can be used as a start shaft of an open shield machine, and the construction is also performed using a conventional small cut beam as a temporary support, and a large frame-shaped cut beam. It is easy because it is only necessary to remove the temporary support with small beams after installing it as a support and installing a large frame-shaped beam as a support.
[Brief description of the drawings]
FIG. 1 is a longitudinal front view showing an embodiment of a simple shaft of the present invention.
FIG. 2 is a plan view showing an embodiment of a simple shaft according to the present invention.
FIG. 3 is a longitudinal front view of a state in which a temporary support construction showing a method for constructing a simple shaft according to the present invention is provided.
FIG. 4 is a plan view showing a state in which temporary support works showing a method for constructing a simple shaft according to the present invention are provided.
FIG. 5 is a longitudinal front view showing a state where a temporary support construction showing a method for constructing a simple shaft according to the present invention is removed.
FIG. 6 is a plan view of a state where a temporary support construction showing a method for constructing a simple shaft according to the present invention is removed.
FIG. 7 is a longitudinal front view of a conventional simple shaft.
FIG. 8 is a plan view of a conventional simple shaft.
FIG. 9 is a longitudinal side view showing an outline of an open shield method.
FIG. 10 is a perspective view of a concrete box.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Open shield machine 1a ... Side wall plate 1b ... Bottom plate 1c ... Tail part 2 ... Shield jack 1d ... Front part 1e ... Middle part 3 ... Bulkhead 4 ... Concrete box 4a ... Left side board 4b ... Right side board 4c ... Upper floor board 4d ... Lower floor board 5 ... Backfill 6 ... Grout material 7 ... Height adjusting material 8 ... Push angle 9 ... Excavator 10 ... Opening
11 ... Blade 12a, 12b, 12c ... During plate
13a, 13b, 13c ... cutting beam 14 ... support work
14a, 14b, 14c ... Cut beam member 15 ... Positioning pin
16 ... Packing material

Claims (4)

While excavating the inside, the retaining plates are sequentially built in multiple stages from the upper stage to the lower stage. A method for constructing a simple shaft, wherein a quadrangular frame-shaped support is disposed and the temporary support is removed and constructed. The method for constructing a simple shaft according to claim 1, wherein the support is composed of divided bodies that are divided into a plurality of stages in the vertical direction. The method for constructing a simple shaft according to claim 1 or 2, wherein a packing material is interposed between the support and the retaining plate. Simplified vertical shaft characterized in that a supporting work using a rectangular frame-shaped beam member is arranged between retaining plates built in order from the upper stage to the lower stage.

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