JP3074374B2 - How to build underground structures - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underground structure which can be constructed without hindrance to upper traffic when a large underground structure such as a railway or a road is excavated in a transverse direction. It relates to a method of constructing an object.

[0002]

2. Description of the Related Art In order to excavate underground structures of a large number of members in the underground such as railways and roads in the transverse direction, protective works for supporting upper traffic are required. Although it is possible to provide a pipe roof that is parallel to the horizontal, etc., it is safe and reliable because the protective work of the underground structure to be excavated underground is not performed as a separate work, but simultaneously with the excavation of the underground structure The following construction methods are known as those which can be constructed at low cost and can be constructed with shallow earth covering.

As shown in FIG. 4, a steel retaining sheet pile 2 is placed beside an upper traffic 1 such as a railway to construct a starting pit 3 and a reaching pit 4, and press-fit into the starting pit 3. The roof cylinder 6 is press-fitted toward the reaching pit 4.

The roof cylinder 6 is a box-shaped cylinder having a substantially square cross section made of a steel pipe, formed continuously in the longitudinal direction via a hook-shaped joint on a side surface, and provided with a friction cutter 7 on an upper surface. The required length can be buried by sequentially connecting in the length direction, and furthermore, it is arranged side by side through a joint.
This arrangement is, for example, a one-character type as shown in FIG.

Next, as shown in FIG. 5, a reaction wall 8 and an underground structure 9 made of a concrete box are set in the starting pit 3, and a propulsion jack 10 is provided between the reaction wall 8 and the underground structure 9.
Is provided at the tip of the underground structure 9, and a small jack 12 is interposed between the tip of the underground structure 9 and the roof cylinder 6.

In FIG. 1, reference numeral 13 denotes a support member for the roof cylinder 6, and reference numeral 14 denotes a stopper for the friction cutter 7, which is provided on the starting shaft 3 side, while a receiving stand 15 is provided on the reaching shaft 4 side.

The small jack 12 is extended to push the roof cylinders 6 one by one while leaving the friction cutter 7 with the underground structure 9 as a reaction force. , This time promotion jack 10
To extend the underground structure 9. In the figure, reference numeral 16 denotes a strut interposed between the propulsion jack 10 and the underground structure 9.

[0008] In this way, the roof cylinders 6 that have come out to the reaching pit 4 are sequentially removed while the advance of the roof cylinder 6 and the advance of the underground structure 9 are alternately repeated.

Then, when the tip of the underground structure 9 reaches the reaching pit 4, the cutting edge 11 and the like are removed and backfill grouting is performed as appropriate to complete the construction.

The underground structure 9 may be connected by suspending a precast concrete box in the starting pit 3 one by one or by placing concrete in the starting pit 3. May be added.

[0011] Further, regarding the method of moving the underground structure 9,
A reaction wall and a center-hole type traction jack are provided on the reaching pit 4 side, and a traction member made of a PC steel wire having one end fixed to the underground structure 9 is pulled by the traction jack. There is also a construction method to draw in.

[0012]

In the construction method in which the roof cylinder 6 and the underground structure 9 are propelled by the rear jack, when the underground structure is divided into a plurality of parts, the rearmost underground structure is propelled. Is obtained only from the rear reaction wall 8, and the reaction wall 8 requires a large strength. Also, in the construction method in which the underground structure 9 is drawn from the reaching shaft 4 side by the PC steel wire, the underground structure 9 is drawn by pulling all the underground structure only with the towing jack on the reaching shaft 4 side. The reaction wall provided on the reaching shaft 4 side requires a large strength.

An object of the present invention is to solve the inconvenience of the prior art, and to provide a method for constructing an underground structure in which a roof cylinder is advanced and a plurality of subsequent underground structures are excavated. And large strength is not required for the reaction wall for propelling or towing each underground structure with jacks,
An object of the present invention is to provide a method of constructing an underground structure that is easy to construct and that can reliably promote each underground structure.

[0014]

According to the present invention, in order to achieve the above object, a roof cylinder is horizontally pressed into a ground from a starting pit and is arranged in parallel with the roof cylinder. In a method of constructing an underground structure in which an underground structure is disposed, a roof cylinder is advanced, and a plurality of subsequent underground structures are excavated, a roof cylinder and a foreground underground structure are connected to each other. A small jack is interposed between them, and a middle pushing propulsion jack is interposed between multiple underground structures, a reaction wall is provided in the starting pit and a main pushing propulsion jack is interposed with the last underground structure A reaction wall is provided on the reaching pit side, and the reaction wall and the rear of the last underground structure are connected by a traction member with a traction jack interposed. Take the small jack and extend the roof cylinder to move it forward. The underground structure of the above is taken up by the reaction of the underground structure behind it, and the push-in jack is extended and excavated.Thus, the roof cylinder and the plurality of underground structures are reacted by the underground structure behind it. Repeating the operation of extending and contracting the small jack and propulsion jack while taking it, repeatedly excavates the roof cylinder and multiple underground structures, and the last underground structure reaches the anchored traction member such as PC steel wire The gist is to take the reaction force at the reaction wall on the pit side and pull with the towing jack, and take the reaction force at the reaction wall on the starting pit side to extend and push the propulsion jack of the main push to make the excavation proceed. Is what you do.

According to the present invention, the underground structure and the roof cylinder other than the rearmost portion take a reaction force from the rear underground structure and the reaction wall on the starting pit side to advance forward by the middle-pushed propulsion jack. At the same time, the underground structure takes a reaction force from the reaction wall on the arrival pit side, pulls it to the arrival pit side with a tow jack such as a PC steel wire using a towing jack, and simultaneously takes a reaction force from the reaction wall on the starting pit side. And push it with the original push jack. Therefore, the reaction force for advancing can be taken simultaneously from multiple places such as each underground structure, reaction wall on the start pit side, reaction wall on the arrival pit side, etc. It is possible to reduce the size.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a vertical sectional side view of a first step showing an embodiment of a method for constructing an underground structure according to the present invention. In the figure, the same reference numerals are used for the same components as those in the conventional example shown in FIGS. Is attached.

As shown in FIG. 1, a construction method according to the present invention also includes a steel sheet pile 2 placed beside an upper traffic 1 such as a railway to construct a starting pit 3 and a reaching pit 4. And the roof cylinder 6 is press-fitted toward the reaching pit 4 with this,
An underground structure 9 composed of a roof cylinder 6 and a concrete box
The underground structure 9 made of a concrete box is divided into a plurality of parts. In this case, the roof cylinder 6 may penetrate to the reaching shaft 4 as shown in the drawing, or may have a length that is short but not penetrated (not shown).

Further, the roof cylinder 6 has a friction cutter 7 mounted on its upper surface.

A small jack 17 is interposed between the roof cylinder 6 and the foreground underground structure 9, and a middle pushing propulsion jack 18 is interposed between the plurality of underground structures 9.
A reaction wall 20 is provided in the starting shaft 3, and a propulsion jack 19 is provided between the reaction wall 20 and the rearmost underground structure 9.

Further, a reaction wall 21 is provided on the reaching shaft 4 side, and for example, a PC steel wire 23 which is a traction member attached to a traction jack 22 fixed to the reaction wall 21 is fixed to a rear underground structure by a fixing tool 24. Settles at the rear of object 9.

In order to advance the underground structure 9 as described above, as shown in FIG. 2, the small jack 17 is extended by a reaction force at the foremost underground structure 9 and the friction cutter 7 is extended.
, The roof cylinder 6 is advanced, and then the foreground underground structure 9 is excavated. In this case, the middle pushing propulsion jack 18 is extended and the small jack 17 is contracted by taking a reaction force at the rear underground structure 9.

The rear underground structure 9 has a reaction wall.
At the same time, the propulsion jack 19 of the main push is extended by taking the reaction force at 20, and at the same time, the reaction force is taken by the reaction wall 21 and drawn into the reaching shaft 4 side by the PC steel wire 24 by the traction jack 22.

In this manner, the roof cylinder 6 and the plurality of underground structures 9 are subjected to a reaction force by the underground structure 9 at the rear thereof while the small jack 17 and the propulsion jacks 18 are successively extended and contracted. Cylinder 6 and multiple underground structures 9
Are excavated one after another.
At 20 and 21, a reaction force is taken to excavate with the main pushing propulsion jack 19 and the towing jack 22.

When one piece of the roof cylinder 6 is extruded toward the arrival shaft 4, it is divided in the longitudinal direction, separated as it is in the horizontal direction, and lifted in a horizontal state as shown in FIG. Remove sequentially.

Then, when the tip of the underground structure 9 reaches the reaching pit 4, the cutting edge 11 and the like are removed, and backfill grout is performed as appropriate to complete the construction.

The small jack 17 interposed between the roof cylinder 5 and the foreground underground structure 9 is not always necessary, and may not be provided.
It advances simultaneously with the excavation of the foreground underground structure 9.

[0027]

As described above, the method of constructing an underground structure according to the present invention provides a method of constructing a roof cylinder and a plurality of subsequent subterranean structures which are preceded by a roof cylinder. Except for the last one of the multiple underground structures, the excavation takes place with another underground structure, so there is no need for a reaction wall, and only the last underground structure is removed from the reaction wall. The reaction force is taken, but in this case, the reaction force is taken from both the reaction wall on the starting pit side and the arrival pit side, so that sufficient reaction force can be secured without increasing the strength of the reaction wall. .

[Brief description of the drawings]

FIG. 1 is a vertical side view of a first step showing an embodiment of a method for constructing an underground structure according to the present invention.

FIG. 2 is a vertical sectional side view of a second step showing an embodiment of the method for constructing an underground structure according to the present invention.

FIG. 3 is a vertical sectional side view of a third step showing the embodiment of the method for constructing an underground structure according to the present invention.

FIG. 4 is a longitudinal sectional side view of a first step of a conventional method of constructing an underground structure.

FIG. 5 is a vertical sectional side view of a second step of the conventional method of constructing an underground structure.

FIG. 6 is a vertical sectional side view of a third step of the conventional method of constructing an underground structure.

FIG. 7 is a front view showing an example of an arrangement state of cylinders.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Upper traffic 2 ... Earth retaining sheet pile 3 ... Starting pit 4 ... Destination pit 5 ... Press-fitting machine 6 ... Roof cylinder 7 ... Friction cutter 8 ... Reaction wall 9 ... Underground structure 10 ... Propulsion jack 11 ... Cutting edge 12 ... Small jack 13 ... Support material 14 ... Stopping member 15 ... Receiving stand 16 ... Strut 17 ... Small jack 18 ... Propulsion jack 19 ... Propulsion jack 20 ... Reaction wall 21 ... Reaction wall 22 ... Towing jack 23 ... PC steel wire 24 ... Fixer

Claims (1)

(57) [Claims] 1. A roof cylinder is horizontally pressed into the ground from a starting pit to be parallel, and an underground structure is disposed behind a roof cylinder remaining in the starting pit. In the method of constructing an underground structure in which a plurality of subsequent underground structures are excavated, a small jack is interposed between the roof cylinder and the foreground underground structure, and the plurality of underground structures are Intermediately pushing propulsion jack is interposed, a reaction wall is provided in the starting pit, and a main pushing propulsion jack is interposed between the last underground structure, and a reaction wall is provided on the reaching pit side,
The reaction wall and the rear part of the rearmost underground structure are connected by a traction member with a traction jack interposed therebetween. The body is advanced, and then the foremost underground structure is counteracted by the rear underground structure to extend and excavate the middle-pushed propulsion jack, and thus the roof cylinder and the plurality of underground structures are thereafter removed. Repeating the operation of extending and contracting the small jack and the propulsion jack sequentially while taking the reaction force at the underground structure of
The roof cylinder and multiple underground structures are sequentially excavated, and the rearmost underground structure pulls the anchoring traction member, such as a PC steel wire, by the reaction force at the reaction wall on the reaching pit side and pulls it with the towing jack. A method of constructing an underground structure, characterized in that a reaction force is taken by a reaction wall on the starting pit side and a propulsion jack is extended and pushed to excavate.