JPH0462299A - Larger section tunnel and construction method thereof - Google Patents

Abstract

PURPOSE:To make it possible to construct a larger section tunnel at a low cost without using a shield machine by overlapping adjacent and formed small diameter tunnels each other in a diametrical direction to combine back filling hardened fillers for the extra small tunnels. CONSTITUTION:Each of small diameter tunnels 4 of which a tunnel structure body 2 is formed is constituted of a cylindrical structure body 6 consisting of a plurality of propelling pipes and backfilling hardened fillers 7 such as concrete or mortar, etc., later placed to the rear side of the cylindrical structure body 6. According to the constitution, a separation size between adjacent small diameter tunnels 4 is set to a size smaller than the outside diameter of the small diameter tunnel 4 itself, and the backfilling hardened fillers 7 mentioned above are overlapped each other to integrate in succession.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a large cross-section tunnel and a method for constructing the same.
In particular, the present invention relates to a large-section tunnel and a construction method thereof, in which a tunnel structure constituting the large-section tunnel is constructed in advance using a plurality of small-diameter tunnels formed by a propulsion method.

[Conventional technology]

In recent years, the need for underground use has increased, and along with this, tunnels are also required to have larger cross-sections.

By the way, various methods of constructing tunnels have already been provided, but with each construction method, the larger the tunnel cross section, the larger the equipment such as shoring, or the expansion of the ground reinforcement area, etc. The cost will be enormous. Further, there is a shield construction method as a tunnel construction method that does not require shoring equipment, etc., but as the tunnel cross section becomes larger, the shield machine used therein naturally becomes larger. It is said that when the excavation diameter of a shield machine increases, the weight generally increases due to the relationship W = 2.5D' to 3.5D'' (D: outer diameter of the shield machine, W: weight of the shield machine). Such a large-sized shield machine is not only extremely heavy, but also requires manufacturing, temporary assembly, transportation, and on-site assembly.

The manpower and costs involved in all aspects of on-site equipment are enormous.

Therefore, the present applicant has previously invented a tunnel as shown in Figure 1O as a tunnel that can achieve a large tunnel cross-section without causing the above-mentioned disadvantages, and has already filed an application (Japanese Patent Application No. 4074/1999). "Large section tunnel and its construction method").

To explain the outline of this large cross-section tunnel, the large cross-section tunnel 20 is formed in an arch shape or a cylindrical shape, and is formed under the earth pressure of the ground. In a large cross-section tunnel consisting of a tunnel structure 2 that opposes the formation of an internal space and a tunnel space 3 formed inside the tunnel structure 2, the tunnel structure 2 is connected to a large number of shield tunnels 21. 21. It is constructed by sequentially installing... This large-section tunnel is constructed by constructing the tunnel structure 2 made up of the shield tunnels 21 in the ground G in advance, and then excavating the portion surrounded by the tunnel structure 2 to create a tunnel space 3. It is assumed that it is constructed by forming. Further, each of the shield tunnels 21 constituting the tunnel structure 2 includes a cylindrical structure 22 formed by assembling segments (not shown), and a back filler formed on the back side of the cylindrical structure 22. Hardened filler 7
Further, the back-filling hardened fillers 7 constituting the adjacent shield tunnels 21 are polymerized (overlapping), so that the back-filling hardened fillers 7 are integrally formed.

According to the above-mentioned large-section tunnel 20, a large-section tunnel can be constructed at low cost using a small-diameter shielding machine, and moreover, by integrating the backfilling hardened filler 7, a strong tunnel structure can be achieved. 2 can be realized, and furthermore, it can be applied to all the natural ground to which the shield method can be applied.

[Problem to be solved by the invention]

By the way, the tunnel 20 can achieve the above-mentioned excellent effects, but when the construction length of the tunnel is short, the tunnel 20 using a shield machine may be used.
If it is 0, it may become expensive.

The present invention has been made in view of the above circumstances, and is a large cross-section tunnel that can achieve the same effects as the large-section shield tunnel described above, but can be constructed at a lower cost without using a shield machine. It is an object of the present invention to provide a cross-sectional tunnel and a method for constructing the same.

[Means to solve the problem]

The invention described in claim 1 of the present invention provides a tunnel structure formed in an arch shape or a cylindrical shape and forming an internal space against the earth pressure of the ground, and a tunnel formed inside the tunnel structure. The tunnel structure is composed of a large number of adjacent small diameter tunnels formed in the longitudinal direction of the tunnel to be constructed, and the small diameter tunnels are assembled by propulsion pipes. It has a cylindrical structure and a hardened backfilling material that is post-cast on the back side of the cylindrical structure, and the hardened backfilling material of each of these small diameter tunnels is similar to the hardened backfilling material that is formed adjacent to the backfilling material. It is characterized in that the small diameter tunnels are integrated by radially overlapping each other.

Moreover, the invention described in claim 2 of the present invention is the large cross-section tunnel according to claim 1, in which the inside of the cylindrical structure is filled with a hardened filler.

In the invention described in claim 3 of the present invention, after an arch-shaped or cylindrical tunnel structure is constructed in advance by radially arranging a large number of small diameter tunnels in the ground, the tunnel structure in the ground is constructed. A method for constructing a large cross-section tunnel by excavating a portion surrounded by a body, wherein the small diameter tunnel includes a propulsion excavator that is formed to have a smaller diameter than the propulsion excavator; A first step of excavating through propulsion pipes that are successively added at the starting part of and a second step of pouring material, and the tunnel structure is constructed by constructing every other small diameter tunnel in advance, and then forming a trailing small diameter tunnel between the preceding small diameter tunnels. Furthermore, the first step of the trailing small diameter tunnel is carried out while cutting a part of the backfilling hardened filler constituting the leading small diameter tunnel together with the ground.

Further, the invention described in claim 4 of the present invention is the method for constructing a large cross-section tunnel according to claim 3, in which the small diameter tunnel is formed with a propulsion excavator having a diameter smaller than that of the propulsion excavator. A first step of excavating via propulsion pipes that are successively added at the starting part of the propulsion excavator, and between a cylindrical structure formed by connecting the propulsion pipes and the excavation hole formed by the propulsion excavator. It is characterized in that it is constructed by a second step of placing a back-filled hardened filler, and a third step of filling the inside of the cylindrical structure with the hardened filler.

Furthermore, in the method for constructing a large cross-section tunnel according to claim 3.4, when the second step is carried out, the cylindrical structure and the backfilling hardened filling are combined. The present invention is characterized in that a hardened filler adhesion prevention means is provided between the material and the material to prevent adhesion between the two.

According to a sixth aspect of the present invention, in the method for constructing a large cross-section tunnel according to the fifth aspect, the hardened filler adhesion prevention means is inserted into the cylindrical structure from an inner space of the cylindrical structure. A method for constructing a large cross-section tunnel characterized by using sugar water to be supplied to the outer surface of the body.

[Effect]

According to the large cross-section tunnel according to the first aspect, since the tunnel structure is constituted by a small diameter tunnel, it is possible to construct the tunnel structure in advance. Additionally, by structurally integrating a large number of small diameter tunnels, it is expected that the tunnel structure will have higher rigidity and higher water impermeability. Further, according to this large-section tunnel, a small-diameter tunnel constituting the tunnel structure can be formed by the propulsion tunnel method.

In the large cross-section tunnel according to the second aspect, the strength of the tunnel structure can be further improved.

According to the method for constructing a large-section tunnel according to the third aspect, the large-section tunnel according to the first aspect can be realized reliably and efficiently. Moreover, since the tunnel structure is completed prior to excavating the tunnel space, there is no need to perform incidental work such as shoring when excavating the tunnel space.

The method for constructing a large cross-section tunnel according to claim 4 is characterized by the large cross-section tunnel according to claim 2.According to the method for constructing a large cross-section tunnel according to claim 5, a cylindrical structure and adhesion with the hardened filler filled on the back side of the tunnel is prevented, and the propulsion tube can be extruded after being filled with the back-filled hardened filler, and the method for constructing a large cross-section tunnel according to claim 3 can be efficiently carried out. Can be implemented.

The method for constructing a large cross-section tunnel according to claim 6 can realize the method for constructing a large cross-section tunnel according to claim 5 at low cost.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a large cross-section tunnel according to claim 1 of the present invention.

This large-section tunnel (hereinafter abbreviated as "tunnel") 1 includes a tunnel structure 2 that is formed into a cylindrical shape as a whole and forms an internal space against the earth pressure of the ground G, and a tunnel structure 2 and a tunnel space 3 formed inside the tunnel.

The tunnel structure 2 includes a large number of small diameter tunnels 4 formed in the longitudinal direction of the tunnel I to be constructed and adjacent to each other.
4. It is composed of... In this embodiment, these small diameter tunnels 4, 4. ... are arranged in a ring shape in the radial direction, so that the tunnel structure 2 has an overall cylindrical shape with a circular cross section.

Each small diameter tunnel 4 constituting the tunnel structure 2 is
As shown in FIG. 2 or FIG. 7, a plurality of propulsion tubes 5,
5. It is composed of a cylindrical structure 6 assembled by... and a hardened filler (backfill hardened filler) 7 such as concrete or mortar that is post-cast on the back side of the cylindrical structure 6. .

However, here, the cylindrical structure 6 is set to have a smaller diameter than the inner diameter of the excavated hole 8 excavated by the propulsion method, and there is a tail void (clearance between the cylindrical structure 6 and the excavated wall surface).
is extremely large.

Further, each of the small diameter tunnels 4 is set so that the distance between the adjacent small diameter tunnels 4 is smaller than the outer diameter of the small diameter tunnel 4 itself.
The back-filling hardened fillers 7 constituting the backfilling material 7 are mutually polymerized. As a result, the hardened backfilling material 7 of each of the small diameter tunnels 4, 4°, . . . is continuously integrated.

In addition, the outer diameter of the tunnel l having the above configuration is, for example, 4 m ~
40m1 Also, the outer diameter of each shield tunnel 4 is approximately 0
．． The length is 7m to 4m.

Next, an example of a method for constructing the tunnel I having the above configuration will be described with reference to FIGS. 3 to 7.

To construct the tunnel I, first, a large number of small diameter tunnels 4, 4 . A tunnel structure 2 consisting of... is constructed in advance within the ground G. Construction of the tunnel structure 2 is performed by the following steps.

That is, first, the small diameter tunnels 4, 4, and 4, which are adjacent to each other at the time of completion shown in FIG. . . . The ones that are arranged every other time (preceding small diameter tunnel 4A) will be constructed in advance (see Figure 3). FIG. 7 shows a method of constructing the small diameter tunnel 4.

Reference numeral 10 in FIG. 7 is a vertical shaft for starting excavation of the small diameter tunnel 4. The small diameter tunnel 4 has a propulsion pipe 5,
5. By pushing out the base end of the cylindrical structure 6, which has already been formed, by means of a jack installed in the shaft 10, the excavator 12 for propulsion at the face is pushed forward. The propulsion excavator 12 has a larger diameter than the cylindrical structure 6 (propulsion tube 5), and therefore the gap between the excavation hole 8 formed by the propulsion excavator 12 and the cylindrical structure 6 ( The tail void) is set extremely large. Then, by the jack 11,
When the propulsion excavator 12 is advanced by one propulsion pipe 5, a new propulsion pipe 5 is added at the rearmost position. Further, the tail void portion formed by the forward movement of the propulsion excavator 12 as described above is sequentially filled with the backfilling hardened filler 7.

Here, in this embodiment, when filling the tail void portion with the backfilling hardened filler 7 as described above, the cylindrical structure 6 of the filling portion
Inject sugar water onto the outer wall of the Sugar water has the effect of preventing the solidification of concrete, and therefore, in this example, the sugar water constitutes the hardened filler solidification prevention means according to the present invention. Although not shown in the drawings, the sugar water is injected by forming an injection hole or the like in the propulsion tube 5 for injecting the sugar water into the tube from inside the cylindrical structure 6 through the injection hole. injection into the outer surface of the shaped structure 6.

As mentioned above, by injecting sugar water into the contact area between the backfilling hardened filler 7 and the cylindrical structure 6, adhesion of both is prevented, and the cylindrical structure 6 (propulsion tube 5) can be pushed. Therefore, it is possible to construct the small diameter tunnel 4 while filling it with the backfilling hardened filler 7.

By the above method, as shown in FIG. 4, if the leading small diameter tunnels 4A, 4A, . ... to form.

FIG. 5 shows the construction status of the trailing small diameter tunnel 4B, and the formation process of the trailing small diameter tunnel 4B is also the same as that of the preceding small diameter tunnel 4A.

However, since the distance between the preceding small diameter tunnels 4A, 4A is set smaller than the diameter of the small diameter tunnel 4 itself as described above, the two preceding small diameter tunnels 4A
When forming the trailing small diameter tunnel 4B between 4A and 4A,
Along with the ground G, a portion of the hardened filler material 7 without backfilling forming the preceding small diameter tunnels 4A, 4A on both sides shall be excavated at the same time. At this time, since the cylindrical structure 6 constituting the preceding small diameter tunnel 4A is formed to have a small diameter, only the backfilling hardened filler 7 can be filled without interfering with the cylindrical structure 6 of the preceding small diameter tunnel 4A. It is possible to cut.

And as above (preceding small diameter tunnel 4A, 4A,...
・If trailing small diameter tunnels 4B, 4B, etc. are formed in between,
As shown in FIG. 6, a tunnel structure 2 is constructed.

By the way, in this construction method, the trailing small diameter tunnel 4
When forming B, a part of the hardened backfilling material 7 of the preceding narrow-diameter tunnel 4A is cut together with the ground G by the propulsion excavator 12, so that the hardened backfilling material constituting the preceding narrowed tunnel 4A is removed. As the material 7, it is more desirable to use a material that has low initial strength and increases in strength over time. As another method, for example, retarded setting concrete is used as the backfill hardening filler 7 of the leading small diameter tunnel 4A, and after construction of the trailing small diameter tunnel 4B,
It is also possible to adopt a method such as feeding high temperature air (for example, 70° C. or higher) into the leading small diameter tunnel 4A to ensure the required strength. At this time, the internal space of the cylindrical structure 6 can be used to supply high-temperature air. Note that it is desirable that the hardened backfilling material 7 for the trailing small diameter tunnel 4B be made of high-strength concrete.

And, as mentioned above, the small diameter tunnel 4.4. If the tunnel structure 2 is constructed by ..., the part surrounded by the tunnel structure 2 in the ground G is excavated to form the tunnel space 3, and the purpose as shown in FIG. 1 is achieved. Tunnel 1 is completed.

Excavation of the internal ground of the tunnel structure 2 is usually carried out using a commonly used excavator, but since the tunnel structure 2 has already been constructed and the ground G is supported by it, no shoring or the like is required. There is no need to provide it.

According to the tunnel I, the tunnel structure 2 is connected to a large number of small diameter tunnels 4.4. ..., it is possible to reliably form a tunnel space 3 having a large cross section. Moreover, each of the small-diameter tunnels 4 that are connected to each other constituting the tunnel structure 2 is integrated by overlapping the backfilling hardened fillers 7 that make up the small-diameter tunnels 4, so that the tunnel structure 2 can be made to have extremely high strength and excellent water-blocking properties.

In addition, each small diameter tunnel 4 is constituted by a propulsion tunnel that can be constructed at a lower cost than a shield tunnel, so it is particularly effective when applied to a large cross-section tunnel with a short tunnel length.

Moreover, if the tunnel 1 having the above configuration is constructed by the above construction method, the tunnel 1 can be realized reliably and efficiently. In particular, the tunnel structure 2 is
Since the construction is carried out in advance of the excavation of the tunnel space 3, the ground G has already been completely stabilized, and a large cross section can be excavated easily and efficiently without the need for shoring. can.

In addition, in the method for constructing the tunnel 1, the following small diameter tunnel 4B does not necessarily have to be formed after all of the preceding small diameter tunnels 4A, 4A, . . . are formed; 4B is at least two parallel leading small diameter tunnels 4A, 4A.
Once formed, the preceding small diameter tunnels 4A may be sequentially formed. Furthermore, it is of course possible to simultaneously construct the small diameter tunnel 4 at several locations using a plurality of propulsion excavators 12.

Next, FIG. 8 shows an embodiment of a tunnel according to claim 2 of the present invention. In this figure, the same components as those in the embodiment described above are given the same reference numerals and their explanations will be omitted.

The tunnel 1' according to this embodiment is the same as the tunnel 1 in which the inner space of the cylindrical structure 6 constituting the small diameter tunnel 4 is solidly filled with a hardened filler 9 such as concrete or mortar. be.

According to this tunnel 1', the rigidity of the tunnel structure 2 can be further improved.

To construct the tunnel 1', in the step of constructing the tunnel 1 in the previous embodiment, after forming the trailing small diameter tunnel 4B following the leading small diameter tunnel 4A as described above,
A hardened filler 9 may be placed inside the cylindrical structure 6 of each of the small diameter tunnels 4.4, .

In each of the above embodiments, the cylindrical structures 6 of the leading small diameter tunnel 4A and the trailing small diameter tunnel 4B are described as having the same diameter, but they may have different diameters. For example, the cylindrical structure 6 of the leading small-diameter tunnel 4A may be formed to have a smaller diameter than the cylindrical structure 6 of the trailing small-diameter tunnel 4B, and by doing so, the overlapping portion of the double-diameter tunnels 4A and 4B can be further reduced. It is possible to make it larger.

Further, in each of the above embodiments, the tunnel ll' (tunnel structure 2) is described as having a circular cross section, but the large cross section tunnel according to the present invention is not limited to having a circular cross section, but has a horseshoe shape. , semicircular, or other cross-sectional shapes are also theoretically possible. In that case, each small diameter tunnel 4.4. The forming position (overlapping position) of... may be determined so that the tunnel structure 2 formed by which small diameter tunnel 4 has a predetermined cross-sectional shape.

Further, in each of the above embodiments, the tunnel structure 2 has a closed cylindrical structure in the vertical cross section, but the large cross section tunnel according to the present invention has a tunnel space, for example, as shown in FIG. 3 (in the illustrated example, the upper half) may be constituted by the tunnel structure 2. In that case, concrete 15 may be placed at the bottom of the tunnel (invert section), and furthermore, the concrete 15 may be reinforced with rock bolts (not shown).

〔Effect of the invention〕

As explained above, according to the large-section tunnel according to the first aspect, since the tunnel structure is constituted by a large number of small-diameter tunnels, a large-section tunnel space can be reliably formed. In addition, the small diameter tunnels that are connected in a tunnel structure are integrated by overlapping the hardened backfilling materials that make up the small diameter tunnels, making the tunnel structure extremely strong. Moreover, it can have excellent water-blocking properties. Moreover, each small diameter tunnel is formed by a propulsion tunnel that can be constructed at a lower cost than a shield tunnel, so it is particularly effective when applied to a large cross-section tunnel with a short tunnel length.

Moreover, according to the large cross-section tunnel according to claim 2, the rigidity of the tunnel structure in the large cross-section tunnel according to claim 1 can be further improved, thereby realizing a stronger large cross-section tunnel. .

Further, according to the method for constructing a large cross-section tunnel according to claim 3, the tunnel according to claim 1 can be realized reliably and efficiently, and in particular, since the tunnel structure is constructed in advance of the tunnel space. , large cross-sections can be excavated easily and efficiently without the need for shoring or the like.

Moreover, the method for constructing a large cross-section tunnel according to claim 4 can realize the large cross-section tunnel according to claim 2.

Furthermore, according to the method for constructing a large cross-section tunnel according to claim 5, the large cross-section tunnel according to claims 1 and 2 can be realized extremely easily and efficiently.

According to the method for constructing a large cross-section tunnel according to claim 6, when a cement-based self-hardening material such as concrete or mortar is used as the backfilling effect filler, the large cross-section tunnel according to claims 1 and 2 is can be constructed efficiently and at low cost.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an embodiment of a large-section tunnel according to claim 1 of the present invention, FIG. 2 is a partial front sectional view showing a tunnel structure according to this embodiment, and FIGS. 3 to 6 7 explains the construction method of the tunnel structure according to this embodiment, and shows a partial front large cross section of the tunnel structure, and a seventh section.
The figure is a side cross-sectional view showing the construction state of a small diameter tunnel, FIG. 8 is a large front cross-section showing an embodiment of a large-section tunnel according to claim 2 of the present invention, and FIG. 9 is another structural example of a tunnel structure. FIG. 10 is a partial front sectional view showing an example of a large-section tunnel previously filed by the present applicant. Fig. 1 G...Ground, 1.1'...Large cross-section tunnel, 2...Tunnel structure, 3...Tunnel space, 4. ...Small diameter tunnel, 4A... Leading small diameter tunnel, 4B... Trailing small diameter tunnel, 5... Propulsion tube, 6... Cylindrical Structure, 7... Back-fill hardened filler, 9... Hardened filler, 12... Propulsion excavator.

Claims (1)

[Claims] 1) Consisting of a tunnel structure formed in an arch or cylindrical shape and forming an internal space against the earth pressure of the ground, and a tunnel space formed inside the tunnel structure. The tunnel structure is a large-section tunnel, and the tunnel structure is composed of a large number of mutually adjacent small-diameter tunnels formed in the longitudinal direction of the tunnel to be constructed, and the small-diameter tunnel is a cylindrical structure assembled by propulsion pipes. and a hardened backfilling material that is post-cast on the back side of the cylindrical structure, and the hardened backfilling material of each of these small diameter tunnels is such that the small diameter tunnels formed adjacent to each other have a hardened backfilling material. A large cross-section tunnel characterized by being integrated by being superimposed on each other in the radial direction. 2) The large cross-section tunnel according to claim 1, wherein the inside of the cylindrical structure is filled with a hardened filler. 3) After constructing an arch-shaped or cylindrical tunnel structure in advance by radially arranging a large number of small-diameter tunnels in the ground, excavating the portion of the ground surrounded by the tunnel structure. A method for constructing a large cross-section tunnel by using a propulsion excavator,
A first step of excavating through propulsion pipes formed to have a smaller diameter than the propulsion excavator and successively added at the starting part of the propulsion excavator, a cylindrical structure formed by connecting the propulsion pipes, and the propulsion excavator. a second step of placing a backfilling hardened filler between the excavated holes formed by an excavator; and the tunnel structure is constructed by constructing every other small diameter tunnel in advance , by forming a trailing small-diameter tunnel between the leading small-diameter tunnels, and the first step of forming the trailing small-diameter tunnel involves removing a portion of the backfilling hardened filler constituting the preceding small-diameter tunnel. A method for constructing large cross-section tunnels, which is characterized by cutting along with the ground. 4) In the method for constructing a large-section tunnel according to claim 3, the small-diameter tunnel is constructed by using a propulsion excavator that is formed to have a smaller diameter than the propulsion excavator and that is successively added at the starting part of the propulsion excavator. A first step of digging through a pipe, and a second step of placing a backfilling hardened filler between the cylindrical structure formed by connecting the propulsion pipes and the excavation hole formed by the propulsion excavator. and a third step of filling the inside of the cylindrical structure with a hardened filler. 5) In the method for constructing a large cross-section tunnel according to claims 3 and 4, when performing the second step, adhesion between the cylindrical structure and the hardened backfilling filler is prevented. A method for constructing a large cross-section tunnel, characterized by applying a means for preventing adhesion of a hardened filler to prevent the adhesion of a hardened filler. 6) In the method for constructing a large cross-section tunnel according to claim 5, the hardened filler adhesion prevention means is sugar water supplied from the inner space of the cylindrical structure to the outer surface of the cylindrical structure. A method for constructing a large cross-section tunnel characterized by: