JPH0681879B2 - Construction method of underground structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention does not hinder upper traffic when excavating a large number of underground structures in the lower ground such as railways and roads in a transverse direction. The present invention relates to a method of constructing an underground structure that can be constructed.

[Conventional technology]

In order to excavate a large number of underground structures in the lower ground such as railroads and roads in the transverse direction, protective work is required to support upper traffic, and a pipe roof that horizontally arranges steel pipes and the like is provided. Is mentioned.

However, if a pipe roof was formed as a separate work and an underground structure was constructed by excavating the pipe roof, or an underground structure was dug under the pipe roof, this pipe roof exists. The soil cover becomes thicker. Moreover, the protection work for pipe roof construction is different from the main construction for burying underground structures, and the construction cost and construction period are large.

Therefore, the inventors of the present invention invented a method for constructing an underground structure as shown in FIGS. 6 to 8, and filed an application as Japanese Patent Application No. 53-89948 (Japanese Patent Application Laid-Open No. 55-19312).

The construction method of the underground structure shown in FIGS. 6 to 8 is
It is possible to construct safely and reliably at low cost because it is performed simultaneously with the excavation of the underground structure without constructing the protective work of the underground structure to be excavated in the ground in advance. First, the contents will be explained, and thus the purpose of the present invention will be clarified.

As shown in FIG. 6, a retaining steel sheet pile 2 is placed beside the upper traffic 1 such as a railway to construct a starting pit 3 and a reaching pit 4, and a press-fitting machine 5 is installed in the starting pit 3. With this, the roof cylinder 6 is press-fitted toward the reaching pit 4. FIG. 9 shows the roof cylinder 6
Is a steel pipe with a rectangular cross section and a hook-shaped joint on the side.
6a and 6b are formed continuously in the longitudinal direction, and a friction cutter 7 made of a flat plate of a steel plate is attached to the upper surface by welding the tips to each other.

The press-fitting machine 5 has an extruding mechanism such as a jack of the cylindrical body 6 and an internal excavating mechanism of the cylindrical body 6 such as an auger.

It should be noted that the roof cylinder 6 has a proper length and is sequentially connected in the length direction to bury the required length. If the first one is press-fitted by the press-fitting machine 5, the press-fitting machine 5 is retracted. The next cylinder 6 is set in the empty space, and the friction cutter 7
They are welded to each other and the tubular bodies 6 are welded to each other to extend the length thereof, and then the press-fitting machine 5 presses them again.

On the other hand, the roof cylinders 6 are arranged side by side through the joints 6a and 6b while being continuously continuous in the lateral direction as shown in FIG.

Next, as shown in FIG. 7, 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. A blade 11 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 the figure, 13 is a support member for the roof cylinder 6, 14 is a stop member for the friction cutter 7, which are provided on the starting pit 3 side, while a pedestal 15 is provided on the reaching pit 4 side.

While extending the small jack 12 and using the underground structure 9 as a reaction force, the tip ends of the welds are separated from each other and the friction cutters 7 are left in the ground, while pushing the roof cylinders 6 one by one.
Once the tubular body 6 has moved forward, the small jack 12 is contracted and the propulsion jack 10 is extended this time to advance the underground structure 9. The excavation of the underground structure 9 by excavation is safely performed under the plate girders in parallel with the roof cylinder 6.

Reference numeral 16 in the figure denotes a strut interposed between the propulsion jack 10 and the underground structure 9.

In this way, the forward movement of the roof cylinder 6 and the underground structure 9
While alternately repeating the forward movement, the portion of the roof tubular body 6 that has come out of the reaching pit 4 is cut off in sequence by sequentially cutting the welded portion and removed.

Then, when the tip of the underground structure 9 reaches the reaching pit 4, the blade opening 11 and the like are removed and backfilling grout is appropriately performed to complete the construction.

The underground structure 9 may be constructed by sequentially suspending and connecting precast concrete boxes in the start pit 3 or by placing concrete in the start pit 3 to increase the required length. You may do it.

Regarding the propulsion method of the underground structure 9, a reaction wall and a center-hole type towing jack are provided on the side of the reaching pit 4, and a towing member made of PC steel wire having one end fixed to the underground structure 9 is used with this towing jack. Reaching pit 4 by pulling
The underground structure 9 can be pulled in from the side.

[Problems to be Solved by the Invention]

By the way, in the method for constructing an underground structure shown in FIGS. 6 to 8, the friction cutter 7 made of a flat plate of a steel plate is press-fitted into the ground together with the roof tubular body 6, and then only the friction cutter 7 is used. Remaining roof cylinder 6
Only promote.

Therefore, when the roof cylinders 6 are sequentially welded and press-fitted, the friction cutter 7 also needs to be welded, and the stop member 14 of the friction cutter 7 provided on the side of the starting pit 3 is The rear end of the newly connected friction cutter 7 must always be fixed.

The labor of such work was very complicated and troublesome.

On the other hand, when the roof cylinder 6 is pressed into the ground by the press-fitting machine 5, if it bends upward, the friction cutter 7 is also set according to this bending, and further bends to propel the underground structure 9. Will occur.

Furthermore, in order to lay the friction cutter 7 from the starting pit 3 to the reaching pit 4, the roof cylinder 6 must also be press-fitted to reach from the starting pit 3 to the reaching pit 4.

The object of the present invention is to eliminate the inconvenience of the conventional example, and to bury the friction cutters horizontally and easily and accurately, thereby aiming to reduce the number of construction steps and the construction period, and to properly propel the cylinder for the roof and thus the underground structure. The object of the present invention is to provide a method for constructing an underground structure, which can obtain appropriate propulsion and can use a short roof cylinder.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention excavates a friction cutter made of a flat plate such as a steel plate from the starting pit to the arriving pit from the ground and horizontally lays it near the surface of the ground, and then bury the roof tubular body with a steel pipe having a rectangular cross section. A small jack is provided at the rear end of the roof cylinder that remains in the starting pit, by horizontally press-fitting it horizontally into the ground from the starting pit so that its upper surface is joined just below this friction cutter, and arranging the rear jack behind the small jack. The underground structure is installed in the ground, and the underground structure is used as a reaction member to push the roof cylinder with a small jack while leaving the friction cutter, and the underground structure is dug by the conventional construction method, or from the start pit. A friction cutter consisting of a flat plate such as a steel plate is excavated from the ground to the arriving pit, and is laid horizontally near the surface of the ground, and then buried. Are horizontally pressed into the ground from the start pit so that the upper surface of the friction cutter is joined directly below, and the underground structure is placed behind the rear end of the roof cylinder that remains in the start pit. The gist is to simultaneously excavate the underground structure and the roof cylinder while leaving the friction cutter.

[Action]

According to the present invention as set forth in claim 1, the friction cutter, which is made of a flat plate such as a steel plate between the starting pit and the reaching pit, is excavated from the ground and is horizontally arranged near the surface of the ground to be buried. It can be laid in the ground.

In this way, if a press-fitting machine is installed in the starting pit and the upper surface of the roof cylinder is joined to the lower surface of the friction cutter so that it is pressed into the reaching pit, the roof cylinder will be smooth. Is pressed into.

Furthermore, a reaction wall, a propulsion jack, and an underground structure consisting of a concrete box are set in the starting pit, a small jack is interposed between the tip of the underground structure and the roof cylinder, and a friction cutter is used as a stop member. While fixing the rear end to the starting pit side, the small jacks are extended and the underground structure is used as a reaction force to push the roof cylinders one by one, and if the cylinders move forward, then the small jacks will be retracted. Extends the propulsion jack to dig underground structures, but since the roof cylinder moves with the friction cutter as a guide, it moves smoothly with a low friction coefficient, and there is no risk of it being pressed upward by the friction cutter. Absent.

Also, since the roof cylinder is always cut off from the friction cutter and there is no connecting part, this roof cylinder must always have a length that penetrates the reach shaft from the beginning. Alternatively, the short roof cylinder can be advanced sequentially with the underground structure.

According to the second aspect of the present invention, the steps up to the press-fitting of the roof cylinder are the same as those of the first aspect of the present invention, and an underground structure including a reaction wall, a propulsion jack, and a concrete box in the starting pit. Set the object, connect the tip of the underground structure and the roof cylinder, and fix the rear end of the friction cutter to the starting pit side with a stop member, while extending the propulsion jack to extend the underground structure and roof. The barrel is digging at the same time.

〔Example〕

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

1 to 5 are side views of respective steps showing one embodiment of the method for constructing an underground structure according to the present invention, and FIG. 6 showing the conventional example.
The same components as those in FIG. 8 are designated by the same reference numerals.

As shown in Fig. 1 and Fig. 2, the retaining steel sheet pile 2 is driven to construct the starting pit 3 and the reaching pit 4, and in parallel with this, the starting pit 3 to the reaching pit 4 are excavated from the ground. The friction cutters 7 are accurately arranged horizontally and buried near the ground surface.

This friction cutter 7 may be buried in a short length as needed by connecting it by welding, and the excavation width for installing one is narrow and the buried part is not deep from the ground, so earth retaining works etc. It is unnecessary and the level is accurate.

Then, at a portion of the upper traffic 1 such as a railway, the friction cutter 7 is laid so as to dive under the upper traffic 1. However, if the temporary receiver 18 is interposed under the upper traffic 1, one friction cutter 7 is buried. Excavation work can be done in a short time without interrupting traffic.

Further, the friction cutters 7 are stored in the excavation trench and then buried back, but the friction cutters 7 arranged in parallel in the lateral direction are buried one by one, and in the length direction, the starting pit 3 side, the reaching pit 4, or The embedding can start from any convenient location in the middle.

After the friction cutter 7 is laid in the ground in this way, the press-fitting machine 5 is installed in the starting pit 3 as shown in FIG. 3 and the hook-like joint 6a is provided on the side surface as shown in FIG. , 6b are formed continuously in the longitudinal direction so that the upper surface of the roof cylinder 6 is joined directly below the friction cutter 7 so that the roof cylinder 6 is press-fitted toward the reaching pit 4 and arranged side by side in the lateral direction.

In the figure, reference numeral 14 denotes a stopper member for the friction cutter 7, whereby the rear end of the friction cutter 7 is fixed to the starting pit 3 side, while the pedestal 15 is provided on the reaching pit 4 side.

Then, as shown in FIG. 4, the reaction wall 8 is set in the starting shaft 3
Furthermore, an underground structure 9 made of a concrete box is set in front of it, a propulsion jack 10 is provided between the reaction wall 8 and the underground structure 9, and a blade opening 11 is provided at the tip of the underground structure 9 and the underground structure 9 is installed underground. A small jack 12 as a propulsion device is interposed between the tip of the structure 9 and the roof cylinder 6.

The roof jack 6 is pushed forward while the small jack 12 is extended and the underground structure 9 is used as a reaction force to leave the friction cutter 7.

Once the tubular body 6 has moved forward, the small jack 12 is contracted, and then the propulsion jack 10 is extended to advance the underground structure 9. The forward movement of this underground structure 9 also applies to the friction cutter 7.
With less friction resistance. Reference numeral 16 in the figure denotes a strut interposed between the propulsion jack 10 and the underground structure 9.

In this way, the forward movement of the roof cylinder 6 and the underground structure 9
While alternately repeating the above-mentioned forward movement, the middle of the roof tubular body 6 that has emerged in the reaching pit 4 is sequentially cut and removed.

When the tip of the underground structure 9 reaches the reaching pit 4, the blade opening 11 and the like are removed and backfilling grout is performed as appropriate to complete the construction.

The friction cutter 7 may be buried as it is,
It may be pulled out from the starting pit 3 or the reaching pit 4 and removed.

The underground structure 9 may be constructed by sequentially suspending and connecting precast concrete boxes in the start pit 3 or by placing concrete in the start pit 3 to increase the required length. You can also do so.

Regarding the propulsion method of the underground structure 9, a reaction wall and a center-hole type towing jack are provided on the side of the reaching pit 4, and a towing member made of PC steel wire having one end fixed to the underground structure 9 is used with this towing jack. Reaching pit 4 by pulling
It is also possible to pull in the underground structure 9 from the side.

Further, as another embodiment, it is not always necessary to press-fit the roof cylinder 6 having a length penetrating the reaching pit 4 into the ground from the beginning, and the short roof cylinder 6 is sequentially arranged with the underground structure 9. You can also move it forward.

By doing so, the length of the roof cylinder 6 can be made shorter than in the conventional case, the material cost can be reduced, the effort of pushing the roof cylinder 6 forward, and the roof cylinder 6 being cut and removed at the reaching hole 4. You can save time.

Still another embodiment is a method without using the small jack 12.

At the stage shown in FIG. 4, the reaction wall 8 is set in the starting pit 3 and further the underground structure 9 made of a concrete box is set in front of it, and between the reaction wall 8 and the underground structure 9. A propulsion jack 10 is provided, a blade 11 is provided at the tip of the underground structure 9, and the tip of the underground structure 9 and the roof cylinder 6 are connected by a frame or the like.

Then, the propulsion jack 10 is extended to simultaneously excavate the underground structure 9 and the roof cylinder 6.

In this way, while the roof cylinder 6 and the underground structure 9 are simultaneously advanced, the middle of the roof cylinder 6 that has emerged in the reaching pit 4 is cut and removed in sequence.

When the tip of the underground structure 9 reaches the reaching pit 4, the blade opening 11 and the like are removed and backfilling grout is performed as appropriate to complete the construction.

〔The invention's effect〕

As described above, the construction method of the underground structure of the present invention aims to reduce the number of construction steps and the construction period by arranging the friction cutters horizontally and easily and accurately, and further, the roof cylinder and thus the upward direction of the underground structure. It is possible to obtain proper propulsion by suppressing the bending of.

Further, it is possible to use a short roof cylinder, which can reduce the cost and the construction period.

[Brief description of drawings]

1 to 5 are side views of respective steps showing one embodiment of the method for constructing an underground structure of the present invention, and FIGS. 6 to 8 show respective steps of a method for constructing an underground structure of the related art. FIG. 9 is a side view, FIG. 9 is a front view of the roof cylinder, and FIG. 10 is a front view showing an arrangement example of the roof cylinder. 1 …… Upper traffic, 2 …… Soil retaining steel sheet pile 3 …… Starting pit, 4 …… Driving pit 5 …… Pressing machine 6 …… Roof cylinder, 6a, 6b …… Joint 7 …… Friction cutter 8 …… Reaction wall, 9 …… Underground structure 10 …… Propulsion jack, 11 …… Blade 12 …… Small jack, 13 …… Supporting material 14 …… Stopping member, 15 …… Bed 16 …… Strut 18 …… Provisional receiving.

Claims (2)

[Claims] 1. A friction cutter made of a flat plate such as a steel plate from the starting pit to the arrival pit is excavated from the ground and horizontally arranged near the surface of the ground, and then buried. Then, a roof cylinder made of a steel pipe having a rectangular cross section is provided directly under the friction cutter. In order to connect the upper surface to the ground, press horizontally into the ground from the starting pit to make them parallel, and provide a small jack at the rear end of the roof cylinder that remains in the starting pit, and place an underground structure behind the small jack. Arranged,
A method for constructing an underground structure, characterized in that the underground cylinder is pushed by a small jack while the friction cutter is used as a reaction force member while leaving the friction cutter, and the underground structure is dug by the conventional method. 2. A friction cutter made of a flat plate such as a steel plate from the starting pit to the arrival pit is excavated from the ground and horizontally arranged and buried near the surface of the ground, and then a roof cylinder made of a steel pipe having a rectangular cross section is provided directly under the friction cutter. The horizontal structure is press-fitted horizontally into the ground from the start pit so that its upper surface is joined to the ground, and the underground structure is placed behind the rear end of the roof cylinder that remains in the start pit. A method of constructing an underground structure, characterized in that the cylinder for work is simultaneously advanced while leaving a friction cutter.