JP5190438B2 - A waterproofing method for a box for an underground structure and a joint between the boxes. - Google Patents

Description

  The present invention relates to a water stop method for a joint for an underground structure and a joint between the boxes.

A large cross-section tunnel is equally divided into a grid of 3-4m vertical and horizontal small tunnels, and each small tunnel is used multiple times with a small mud pressure type rectangular shield machine. The method of excavating the body as a stack of blocks and excavating a tunnel with a large cross section is known under the name of “Harmonica Method”.
In this construction method, the excavator uses an oscillating type in order to minimize the uncut portion with respect to the excavation of the rectangular cross section.
Also, in order not to create a gap between the boxes of the small tunnel, the thrust uses a propulsion system with a push jack.
This construction method is characterized in that the rear case is constructed by contacting the preceding case, and it is necessary to perform the construction while maintaining the contact state between the cases.
Therefore, a protrusion is formed on the surface of one box, and a groove is formed on the surface of the other box to form a joint, and one protrusion is slid into the other groove to dig. The method is adopted.

Japanese Patent No. 3762603.

The above-described conventional method has the following problems because it constructs a large number of small tunnel boxes in parallel.
<1> In order to prevent water leakage from between the boxes, the water-stopping height of the joint portion connecting the boxes is an important condition.
<2> However, there are many cases where the backing material or excavated earth and sand has entered and solidified in the joint, and when the water-stopping material is filled as it is, the water-stopping material is not filled in the joint. It tends to be incomplete.
<3> Therefore, as a method of removing earth and sand and solidified backing material, there is a method of inserting a pipe or hose that injects high-pressure water into the joint, and removing earth and sand or backing material with the high-pressure water jetted from there. It has been adopted.
<4> However, in reality, it is difficult to completely remove earth and sand and the backing material by washing with high-pressure water. If it cannot be removed by any means, the steel is either washed from the washing hole provided in the joint or cut. The method of performing secondary water stop auxiliary between shells was adopted.
<5> However, cleaning from the cleaning hole provided in the joint portion is time-consuming and time-consuming and has a heavy burden both on a later-described basis and economically.
<6> Secondary water stoppage, which is performed as an auxiliary, is also performed by manually drilling and cleaning the solidified backing material sandwiched between the narrowed steel plates, and using water as a raw material for polymer cement. It was a very expensive and expensive work to inject material.
<7> In addition, a bag-shaped material is placed between boxes, a method of filling a water-stopping material in this, a method of placing a water-stopping plate, excavating a surplus portion, and injecting the filler here A method of providing a water stop structure has been proposed, but there are problems such as complicated material installation means, high material costs, and high machine costs.
<8> Since the conventional means have the problems as described above, a method and a structure capable of easily and reliably cleaning the joint portion between the boxes and ensuring the water stop performance have been demanded.

In order to solve the problems as described above, the box for an underground structure of the present invention is a box used for a method of constructing an underground structure by joining a plurality of tunnel boxes installed in parallel. Then, a guide groove parallel to the tunnel axis direction is formed on one surface of the box, and a protrusion that can be fitted into the guide groove is provided on the other surface of the box.
A wire is arranged at the bottom of the guide groove, and the end of the wire is exposed inside the tunnel box.

Further, the water stopping method for the joint portion between the boxes according to the present invention is such that the protrusion or guide groove of the tunnel box that follows is fitted to the guide groove or protrusion of the tunnel box that has been previously promoted. And after digging,
It features a water stop method for joints between boxes that removes the wire placed at the bottom of the guide groove to create a string trace cavity and fills the inside of the string trace cavity with a waterproof material. is there.
Further, the present invention is characterized by a water stopping method for the joint portion between the boxes, which is performed by performing high-pressure water cleaning using the string trace cavity and filling the water stopping material into the cleaned cavity.

Since the water-stopping method for the joint between the boxes according to the present invention is as described above, the following effects can be obtained.
<1> Since the wire is slidably disposed in the guide groove parallel to the axial direction of the tunnel, a string trace cavity that connects the two tunnel entrances can be formed by removing the wire.
<2> Since the water-stopping material is filled into the string trace cavity from which the wire has been removed in this way, the water-stopping material can be reliably filled into the entire extension of the joint portion between the two wellheads.
<3> Even if the backing material injected between the two boxes has entered the joint, there is a wire at the bottom of the guide groove, so that the space of that part is not affected by the backing material, A complete string cavity can be formed by drawing and removing the wire.
<4> If the string trace cavity formed by removing the wire is used for cleaning with high-pressure water to expand the cavity and the interior is filled with a water-stopping material, the water-stopping effect is more certain.
<5> Since only the wire is used to form the cavity, it is inexpensive and economical.

Explanatory drawing of the state which excavates the box of this invention in parallel. Explanatory drawing of the state which has arrange | positioned the wire to the guide groove of a box. Explanatory drawing of the state which removed the wire and formed the string trace cavity. Explanatory drawing of the state which expanded the string trace cavity. Explanatory drawing of the state which filled the string trace cavity with the water stop material. Sectional drawing of the large-section tunnel completed by connecting the boxes with joints.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

<1> Precondition.
The construction method of the present invention is based on the premise of constructing a large tunnel b by constructing a plurality of small tunnels a adjacent to each other and connecting them together as shown in FIG.
The small tunnel a excavator is not configured as a shield tunnel in which the box is pushed out from the inside of the excavator so as not to form a dimensional difference with the tunnel box, and the tail end of the box is pressurized from the vertical shaft and propelled And adopting a configuration to reach the vertical shaft at the other end.
The present invention provides a configuration and a method for improving the water stoppage of the joint portion c between the boxes in such construction.

<2> Box.
The box 1 of the small tunnel a is a rectangular cylinder, in which a plurality of main girders in the tunnel axis direction are connected by cross-sectional ribs, and the outer periphery thereof is surrounded by an outer shell of a steel plate.
When constructing the small tunnel a, the excavator 2 is positioned at the front end of the box 1 and excavated with a group of bits in front of the excavator 2, and the tail end of the box 1 is pressurized from behind with a propulsion jack. And press it to the shaft at the other end.
These box structures and tunnel construction methods are known.

<3> Joint part.
A guide groove 3 parallel to the tunnel axis direction is formed on one surface of the box 1.
Further, a protrusion 4 that can be fitted into the guide groove 3 is provided on the other surface of the box.
When the protrusion 4 of the adjacent box 1 is fitted into the guide groove 3 of one box 1 and propelled, both boxes 1 are positioned in parallel in the ground.

<4> Wire arrangement.
At the bottom of the guide groove 3, as shown in FIG. 2, a wire 5 is disposed over the entire length in parallel with the axial direction of the tunnel.
Both ends or one end of the wire 5 is exposed inside the tunnel box 1.
For this purpose, the outlet 31 of the wire 5 is opened at the bottom of the guide groove 3 and is normally closed with a water stop lid.
The wire 5 is pulled out to the inside of the tunnel box 1 through a small-diameter hole penetrating the water blocking lid.
The drawing positions of the wires 5 are arranged at an appropriate interval. However, when a plurality of wires 5 are arranged, two ends of the front and rear wires 5 are drawn out from one drawing outlet.

<5> Tunnel construction.
A jack is installed at the starting shaft, and the excavator 2 is arranged at the tip of the box 1, and the box 1 is sequentially pressed into the ground by pressurizing with a jack from the tail end to construct a small tunnel a.
When the box 1 of the small tunnel a penetrates to the reaching shaft, the excavation is finished.
A wire 5 is disposed at the bottom of the guide groove 3 of each box 1.

<6> Construction of a follow-up tunnel.
Propulsion is performed in the same manner in a state in which the protrusion 4 of the box 1B of the succeeding tunnel is fitted in the guide groove 3 on the side surface of the box 1A of the preceding tunnel.
Each box 1 is pressed into the ground sequentially from the starting shaft.
As the box 1B of the subsequent tunnel advances, a joint portion c between the boxes 1 is formed over the entire length of the tunnel.

<7> Injection of backing material.
After the tunnel excavation is completed, the backing material 6 is injected from the inside of the box 1 to the outer peripheral ground.
The backing material 6 flows between the box 1 and the box 1 and flows into the gap between the guide groove 3 and the protrusion 4 of the joint portion c and is solidified.
Also in this case, since the wire 5 is located at the bottom of the guide groove 3, the penetration of the backing material 6 can be eliminated only at that portion.

<8> Formation of a cavity. (Figure 3)
After the excavation is completed, the wire 5 is reciprocated from the inside of the tunnel box 1 through the end of the wire 5.
As a result, since the wire 5 is insulated from the backing material 6, if the wire 5 is pulled out and removed, the trace cavity 7 can be formed in the trace.
This string trace cavity 7 penetrates from the starting shaft to the reaching shaft.

<9> Filling with a water stop material.
Thus, since the string trace cavity 7 has penetrated from the starting shaft to the reaching shaft, if the water-stopping material 8 is filled from any of the shafts or the intermediate outlet 31, the strip-shaped water stop is formed over the entire length. A band of material 8 can be formed.
If the diameter of the wire 5 is large, the cross-section of the string trace cavity 7 becomes large, so that the water can be completely stopped at the joint portion c just by filling the water stop material 8 therein.
In this case, since the conventional cleaning operation is unnecessary, the labor can be omitted, and the construction period of the water stoppage can be greatly shortened.

<10> Cleaning using a cavity. (Fig. 4)
Further, it is possible to perform cleaning by inserting a nozzle of high-pressure water using the string trace cavity 7 and spraying from the nozzle.
In particular, when the cross-section of the string trace cavity 7 is not sufficiently large compared to the gap between the tip of the protrusion 4 and the guide groove 3, the high-pressure water is washed to enter the gap between the tip of the protrusion 4 and the guide groove 3. It is meaningful to remove the backing material 6 and enlarge the cavity 7.
The water-stopping material 8 is injected into the string trace cavity 7 after being cleaned and expanded in this way, and the gap between the tip of the protrusion 4 and the guide groove 3 is completely filled to ensure high water-stopping.

a: Small tunnel b: Large tunnel c: Joint part 1: Box 1A: Box of preceding tunnel 1B: Box of trailing tunnel 2: Excavator 3: Guide groove 4: Projection 5: Wire 6: Backing Material 7: String trace cavity 8: Water stop material

Claims (3)

A box used for a method of constructing an underground structure by joining multiple tunnel boxes installed in parallel,
A guide groove parallel to the tunnel axis direction is formed on one side of the box,
On the other side of the box, a protrusion that can be fitted into the guide groove is provided,
Place the wire at the bottom of the guide groove,
The end of this wire was exposed inside the tunnel box,
Box for underground structures.
Use the box for underground structures according to claim 1,
In the guide groove or ridge of the box that was previously propelled,
Engage with the protrusion or guide groove of the box that follows,
After the end of the excavation,
Remove the wire placed at the bottom of the guide groove to create a string trace cavity,
This is done by filling the inside of the string trace cavity with a water stop material,
Water stop method for joints between boxes for underground structures.
Perform high pressure water washing using the string trace cavity,
Fill the cavity after cleaning with a water-stopping material,
The water stop method of the joint part between the boxes for underground structures of Claim 2.

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