JPH0681878B2 - 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 construction method for an underground structure as shown in FIGS. 6 to 8, and previously disclosed Japanese Patent Application No. 53-89948 (Japanese Patent Application Laid-Open No. 55-19312) and Japanese Patent Application No. 62-62. -82484 (Japanese Patent Laid-Open No. 63-2474)
No. 95) etc.

The construction method of this underground structure 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 is a front view of the roof cylinder 6, which is a steel pipe having a rectangular cross section, and has hook-like joints 17a and 17b continuously formed on the side surfaces in the longitudinal direction, and a friction cutter 7 made of a flat plate on the upper surface. Is installed.

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.

The roof cylinders 6 are sequentially connected in the lengthwise direction to bury the required length, and are further arranged in parallel laterally via the joints 17a and 17b. This arrangement is shown in Figure 10.
As shown in FIG. 12, various types such as a one-letter type, a gate type, and a rectangular box type can be selected.

Next, as shown in FIG. 7, 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 is interposed between the tip of the 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.

The small jacks 12 are extended to push the roof cylinders 6 one by one while leaving the friction cutter 7 as a reaction force of the underground structure 9, and when the cylinders 6 are advanced, the small jacks 12 are contracted. Extends the propulsion jack 10 to advance the underground structure 9. 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 roof cylinder 6 that has come out to the reaching pit 4 is sequentially 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 conventional method of constructing an underground structure, all the cylinders 6 for the roof are arranged (all of the one-letter type, the gate type, and the quadrangular arrangement shown in FIGS. 10 to 12) to reach the pit 4. Are arranged in advance, and while alternately repeating the advancing of the roof cylinder 6 and the advancing of the underground structure 9 arranged side by side, the roof cylinder 6 that has come out of the reaching pit 4 is sequentially removed by appropriately cutting it. I was going to do it.

As a result, although the roof cylinders 6 are all arranged in the same length, the length from the starting pit 3 to the reaching pit 4 is long, and the material cost rises, and it is difficult to push all of them. The work of cutting and removing all of these in 4 is also a large-scale work.

Further, when the roof cylinder 6 is press-fitted into the ground, the roof cylinder 6 is sequentially connected in the length direction to bury the required length.
Since it is connected in parallel in the lateral direction through 17b and connected in the longitudinal direction in this way, we are pushing forward,
It was difficult to accurately promote the whole.

The object of the present invention is to eliminate the inconvenience of the conventional example, save the length of the roof cylinder, save the material cost, labor cost, etc., and shorten the construction period. Therefore, it is an object of the present invention to provide a method for constructing an underground structure that improves construction performance.

[Means for Solving the Problems]

MEANS TO SOLVE THE PROBLEM This invention achieves the said objective, the cylindrical cylinder for roofs which formed the hook-like joint continuously in the longitudinal direction on the side surface is press-fitted horizontally in the ground from a starting pit, and these parallel cylinders are used. A propulsion device is connected to the rear end of the propulsion device by a small jack, an underground structure is arranged behind the propulsion device, and the underground structure is pushed by the propulsion device while using the underground structure as a reaction member. In the method of constructing an underground structure that is excavated by the conventional construction method, some of the roof cylinders that are juxtaposed are accurately penetrated first to the pit, and the rest are short cylinders that guide the cylinder that penetrates ahead. The gist is that the short roof cylinder located in front of the side of the underground structure is gradually shortened from the upper part to the lower part.

[Action]

According to the present invention as set forth in claim 1, the underground structure to be excavated by the conventional method is always protected in front of it by the roof cylinder, so that safe excavation can be performed and the roof cylinder can be used. Since is a short cylinder except for a part, it is cheaper than the case where all cylinders are long, and the construction period for propulsion and removal is short.

In addition, a part of the roof cylinder is accurately penetrated to the reaching hole, and the remaining short roof cylinder pushes the roof cylinder to the guide, so that accurate propelling can be performed as a whole.

According to the second aspect of the present invention, in addition to the above-described action, a roof can be formed that matches the angle of repose of excavation of an underground structure, and the length of the short roof cylinder can be further shortened.

〔Example〕

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

1 to 4 are side views of respective steps showing one embodiment of the method for constructing an underground structure of 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, the start-up pit 3 was constructed by placing the soil retaining steel sheet pile 2.
And a reaching pit 4 are built, and a press-fitting machine 5 is installed in the starting pit 3 so that a hook-like joint 17a, 17 is formed on the side surface as shown in FIG.
The second roof cylinder 6a is formed by continuously forming b in the longitudinal direction.
As shown in the figure, it is press-fitted toward the reaching shaft 4, but only one roof cylinder 6a is accurately arranged.

In the figure, these are stopper members for the friction cutter 7, which are provided on the side of the starting pit 3 and, on the other hand, are provided with a pedestal 15 on the side of the reaching pit 4.

In addition, the propulsion of the roof cylinder 6a is performed by manual excavation (the cylinder 6a
It is preferable that a worker enter inside and excavate the tip soil by human power).

When the arrangement of the roof cylinder 6a is completed, as shown in FIG. 5, the other roof cylinders 6b to 6h having hook-shaped joints 17a and 17b formed continuously on the side surface in the longitudinal direction are formed. Although the joints are connected in parallel to each other in the same manner as in the conventional example, the roof cylinders 6b to 6h are made as short as about 5 to 8 m.

Next, the reaction force wall 8 is set in the starting shaft 3 as shown in FIG.
Further, 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 provided underground. A small jack 12 as a propulsion device is interposed between the tip of the structure 9 and the roof cylinders 6a to 6h.

The small jack 12 is extended and the underground structure 9 is used as a reaction force to push the roof cylinder 6a while leaving the friction cutter 7, and the small jack 12 is extended and the roof cylinder 6a is used as a guide for a short roof cylinder. Push the bodies 6b to 6h by machine digging.

When the tubular bodies 6a to 6h have moved forward, the small jack 12 is contracted, and the propulsion jack 10 is extended this time to advance the underground structure 9. Reference numeral 16 in the figure denotes a strut interposed between the propulsion jack 10 and the underground structure 9.

In this manner, while the forward movement of the roof cylinders 6a to 6h and the forward movement of the underground structure 9 are alternately repeated, the middle of the roof cylinder 6a that has come out to the reaching pit 4 is sequentially cut and removed.

If the roof cylinders 6a to 6h reach the reaching pit 4, they are removed without cutting, and if the tip of the underground structure 9 reaches the reaching pit 4, the blade opening 11 etc. And then backfill grout appropriately 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.

By the way, the short roof cylinders 6b to 6h may have the same length, but as illustrated, the cylinders 6c to 6h located in front of the side of the underground structure 9 are thing
From 6c, 6d to the lower parts 6e, 6g and 6f, 6h, the length was gradually reduced.

In that case, if the difference in the tips of these cylinders 6c, 6d and 6e, 6g and 6f, 6h is set so as to match the repose angle of the earth and sand in the excavation when the underground structure 9 is propelled, the roof cylinder 6a ~ 6h
The protective roof formed by is sufficient for the cylinders 6b to 6h.
The length of can be kept to the minimum necessary.

Further, in the above-described embodiment, only one roof cylinder 6a is provided so as to reach the reaching pit 4, but it is also possible to provide a plurality of roof cylinders 6a.

〔The invention's effect〕

As described above, the method for constructing an underground structure of the present invention is to horizontally press-fit a roof cylinder having a hook-shaped joint formed continuously on the side surface in the longitudinal direction from the start pit into the ground. , Connecting a propulsion device with a small jack to the rear end of these roof cylinders, disposing an underground structure behind the propulsion device, and pushing the roof cylinder with the propulsion device using the underground structure as a reaction member At the same time, the underground structure can be excavated by the conventional method.In the construction method of the underground structure, the length of the roof cylinder can be made shorter than before, saving the material cost, the effort of pushing the roof cylinder, and the roof structure. It is possible to reduce the time and labor required to cut and remove the tubular body at the arriving shaft.

Furthermore, some of the roof cylinders are accurately penetrated to the pit, and the remaining short roof cylinders push the roof cylinders to the guides, so accurate propelling can be achieved as a whole, and construction of underground structures can be performed. Reliability is also improved.

[Brief description of drawings]

1 to 4 are side views of each step showing one embodiment of the method for constructing an underground structure of the present invention, FIG. 5 is an explanatory view showing the arrangement of the roof cylinder, and FIGS. 6 to 6 are the same. Fig. 8 is a side view showing each step of the conventional method of constructing an underground structure, Fig. 9 is a front view of a roof cylinder, and Figs. 10 to 12 are front views showing an arrangement example of a roof cylinder. Is. 1 ... Upper traffic, 2 ... Suchidome steel sheet pile 3 ... Starting pit, 4 ... Driving pit 5 ... Pressing machine 6,6a to 6h …… Roof cylinder 7 …… Friction cutter 8 …… Reaction wall , 9 ...... Underground structure 10 ...... Propulsion jack, 11 ...... Blade 12 ... Small jack, 13 ...... Support material 14 ...... Stopping member, 15 ...... Stand 16 ... Struts 17a, 17b ...... Joint .

Claims (2)

[Claims] 1. A roof cylinder having a hook-like joint formed continuously on its side surface in the longitudinal direction is press-fitted horizontally from the start pit into the ground to be juxtaposed in parallel with each other. Connect a propulsion device with a jack, place an underground structure behind the propulsion device, and use the underground structure as a reaction member to push the roof cylinder with the propulsion device, and also excavate the underground structure using conventional construction methods. In the construction method of the underground structure, a part of the parallel cylindrical cylinders for the roof is accurately penetrated to the arrival pit first, and the remaining is a short cylinder pushed forward to the guide. Construction method for underground structures. 2. The method for constructing an underground structure according to claim 1, wherein the short roof cylinder located in front of the side surface of the underground structure is gradually shortened from the upper part to the lower part. .