JP6558904B2 - Pile guide guide member and tunnel ground support method - Google Patents

Description

  The present invention relates to a guide member for guiding a pile for suppressing settlement of a support work and a tunnel ground support method using the guide member.

  When excavating a tunnel, it is well known to support the inner wall of the tunnel by successively installing arch-shaped supporters on the inner wall of the newly excavated portion. By embedding the pile from the legs of the support construction obliquely downward, that is, away from the center of the tunnel as it goes downward, the settlement of the support work is suppressed, and consequently the land subsidence above the tunnel is suppressed. It is also well known to do.

  In order to orient the pile accurately, in Patent Document 1, a guide member is fixed in the vicinity of the lower end of an arch member made of H-shaped steel for support. The guide member has a plate portion and a plurality of cylindrical portions penetrating the plate portion, and an internal space of the cylindrical portion serves as a guide passage and guides a pile extending obliquely downward.

Japanese Patent No. 4757620

  In the guide member described in Patent Document 1, a plurality of piles extending obliquely downward extend in parallel to a vertical plane (vertical plane on which a support work is arranged) perpendicular to the depth direction of the tunnel, and the excavation proceeds from this. It does not have a role to support the ground (the ground ahead of the excavation direction).

The present invention solves the above-mentioned problem, and is provided at a leg of a tunnel support work and guides a pile for suppressing settlement of the support work, and a plurality of guide passages for passing the pile. A vertical plane in which at least one central axis of the plurality of guide passages is perpendicular to the depth direction of the tunnel. It is characterized in that it is inclined with respect to and extends obliquely downward in the excavation direction.
According to this structure, the ground which is going to advance excavation from now on can be supported by the pile extended diagonally downward in the excavation direction, and excavation work can be performed smoothly.

Preferably, the extending directions of at least two central axes of the plurality of guide passages are different from each other.
According to this structure, the load burden of a support work can be disperse | distributed.

Preferably, at least two central axes of the plurality of guide passages extend obliquely downward in the excavation direction, and are orthogonal to the tunnel depth direction of the at least two central axes when viewed from the side of the tunnel. The inclination angles with respect to the vertical plane are different from each other.
According to this configuration, it is possible to better support the ground on which excavation is to be advanced and to distribute the load burden.

Preferably, when viewed from the depth direction of the tunnel, inclination angles of at least two central axes of the plurality of guide passages with respect to a vertical plane extending in the depth direction of the tunnel are different from each other.
According to this configuration, the load burden can be distributed.

Preferably, the guide member includes three or more guide passages, and the central axis of all the guide passages is inclined so as to be separated from the tunnel center as it goes downward, and extends obliquely downward in the excavation direction. The central axes of the passages extend in different directions.
According to this configuration, it is possible to maximize the support of the ground to be excavated and the dispersion of the load burden.

  According to another aspect of the present invention, in the tunnel ground support method, the guide member is fixed to a leg portion of the support work, and the piles are respectively inserted into the plurality of guide passages of the guide member to be underground. And supporting the ground in front of the excavation direction by inclining at least one pile with respect to a vertical plane perpendicular to the tunnel depth direction and extending obliquely downward in the excavation direction. Features.

  ADVANTAGE OF THE INVENTION According to this invention, the ground which is going to advance excavation can be supported, and excavation work can be performed smoothly.

It is the schematic front view which looked at the settlement suppression structure incorporating the guide member which makes 1st Embodiment of this invention, and the support work from the depth direction of the tunnel. It is the schematic side view which looked at the said settlement suppression structure and support work from the side of the tunnel. It is a front view of the guide member used for the said settlement suppression structure. It is a top view of the guide member. It is the principal part enlarged front view which looked at the said settlement suppression structure from the depth direction of the tunnel. It is a principal part enlarged plan view of the above-mentioned settlement control structure, and about a pile, only a portion below a base board is shown with an imaginary line. FIG. 7 is a view corresponding to FIG. 6 of a settlement restraining structure incorporating a guide member according to a second embodiment of the present invention.

Hereinafter, a settlement restraining structure of a tunnel support work incorporating a guide member constituting a first embodiment of the present invention will be described with reference to FIGS.
1 and 2 schematically show the entire structure of the support work 1 and the settlement restraining structure 5. The support 1 includes an arch member 2 made of H-shaped steel curved in a substantially semicircular shape, and horizontal base plates 3 fixed to both lower ends of the arch member 2. A leg portion 1 a of the support 1 is configured by the vicinity of the lower end of the arch member 2 and the base plate 3.

  In the tunnel excavation process, the support 1 is installed on the inner wall of the tunnel every time a predetermined distance is excavated. As a result, the support works 1 are installed one after another along the depth direction of the tunnel every predetermined distance, for example, every 1 m, and support the inner wall of the tunnel.

  Each time the latest support work 1 is installed, the both legs 1a are provided with a settlement restraining structure 5. Each settlement restraining structure 5 includes a plurality of, for example, three piles 11, 12, and 13 that are embedded so as to be separated from the center of the tunnel toward the lower side, and guides to be described later that guide these piles 11, 12, and 13. A member 20 is provided. The piles 11, 12, and 13 are made of, for example, a steel pipe having a large number of holes in the peripheral wall.

  Each time the latest support 1 is installed, in addition to the settlement restraining structure 5, a pile extending obliquely upward in the excavation direction from the ceiling wall of the tunnel is buried, or piles are buried radially on the tunnel inner wall. Since it is not the gist of the present invention, a detailed description is omitted.

  As shown in FIGS. 3 and 4, the guide member 20 includes a plate-shaped plate portion 25 (base portion) and a plurality of, for example, three cylindrical portions fixed to the plate portion 25 so as to penetrate the plate portion 25. 21, 22 and 23. The internal spaces of the cylindrical portions 21, 22, and 23 are provided as guide passages 21a, 22a, and 23a that guide the piles 11, 12, and 13, respectively.

  As shown in FIG. 4, the plate portion 25 of the guide member 20 has a plurality of mounting holes 25a on one side edge portion thereof. As shown in FIG. 6, the screw 26 is screwed into a screw hole formed on one side edge of the base plate 3 (for example, a side edge in the tunnel excavation direction F) from the mounting hole 25 a, thereby The part 25 is fixed horizontally to the base plate 3. In the base plate 3, the guide member 20 may be fixed to the side edge portion on the opposite side of the tunnel excavation direction F.

  As shown in FIGS. 3 and 4, the central axes 21a ', 22a', 23a 'of the guide passages 21a, 22a, 23a of the guide member 20 are not parallel to each other but extend in different directions. Hereinafter, with respect to the extending direction of the central axes 21a ′, 22a ′, and 23a ′, a vertical plane A extending in the depth direction of the tunnel and a vertical plane B orthogonal to the depth direction, for example, the vertical plane B on which the support work 1 is arranged are used as a reference. explain. These vertical planes A and B are orthogonal to each other.

As shown in FIG. 3, when the guide member 20 is fixed to the base plate 3 of the support 1 and viewed from the tunnel depth direction, the central axes 21a ', 22a', 23a of the guide passages 21a, 22a, 23a are shown. 'Is inclined so as to be separated from the tunnel center as it goes downward, and the angles θ _1A , θ _2A , and θ _3A with respect to the vertical plane A are different from each other. For example, θ _1A > θ _2A > θ _3A .

As shown in FIG. 4, with the guide member 20 fixed to the base plate 3 of the support 1, the center axis lines 21a ', 22a', 23a 'of the guide passages 21a, 22a, 23a are directed downward. The angle θ _1B , θ _2B , and θ _3B with respect to the vertical plane B are different from each other when viewed from above the tunnel so as to be inclined in the excavation direction F. For example, θ _1B <θ _2B <θ _3B .

As described above, since the central axes 21a ′, 22a ′, 23a ′ of the guide passages 21a, 22a, 23a extend obliquely downward in the excavation direction F, when viewed from the side of the tunnel, that is, the direction perpendicular to the tunnel depth direction. The central axes 21a ′, 22a ′, 23a ′ of the guide passages 21a, 22a, 23a are inclined with respect to the vertical plane B, and the angles θ _1B ′ of the central axes 21a ′, 22a ′, 23a ′ with respect to the vertical plane B, θ _2B ′ and θ _3B ′ are also different from each other. For example, θ _1B ′ <θ _2B ′ <θ _3B ′. These angles θ _1B ′, θ _2B ′, and θ _3B ′ are not shown because they can be easily estimated from FIGS.

  In a state where the guide member 20 having the above-described configuration is fixed to the leg portion 1a of the latest supporter 1, the piles 11, 12, and 13 are respectively inserted into the guide passages 21a, 22a, and 23a of the guide member 20 and obliquely into the ground. Buried underneath. The piles 11, 12, and 13 extend along the central axes 21a ', 22a', and 23a 'of the guide passages 21a, 22a, and 23a. By using the guide member 20, the piles 11, 12, and 13 are accurately oriented and embedded. After the piles 11, 12, and 13 are buried, a coagulant is injected to infiltrate and solidify into the ground.

The piles 11 to 13 buried obliquely below the settlement suppression structure 5 can suppress the settlement of the legs 1 a of the support work 1.
Since the piles 11 to 13 are inclined with respect to the vertical plane B and extend obliquely downward in the excavation direction F, they can bear the load of the ground to be excavated (the ground in front of the excavation direction) and can suppress the settlement thereof. .
Since the piles 11, 12, and 13 extend in different directions, the load burden can be dispersed.

  FIG. 7 shows a second embodiment of the present invention. In this embodiment, the guide member 20 is fixed to the underground side of the base plate 3 of the support 1, that is, the side edge portion far from the tunnel center. Others are the same as in the first embodiment.

The present invention is not limited to the above-described embodiment, and various aspects can be adopted. For example,
The guide member may have two guide passages or three or more guide passages.
The guide member may be fixed near the lower end of the arch member of the support work. The guide member may be formed with a guide passage for guiding not only a pipe buried obliquely below but also a pile buried in the horizontal direction.
All or some of the central axes of the plurality of guide passages may extend in parallel to each other.

  The present invention can be applied to a guide member for guiding a pile for suppressing settlement of a tunnel support work.

DESCRIPTION OF SYMBOLS 1 Supporting work 1a Leg 5 of supporting work Settlement suppression structure 11-13 Pile 20 Guide member 21a, 22a, 23a Guide passage 21a ', 22a', 23a 'Center axis A of guide passage A Vertical plane B extended in tunnel depth direction Vertical plane F perpendicular to the depth direction

Claims (3)

A flat plate-shaped guide member that is horizontally fixed to the leg of the tunnel support and guides the pile for suppressing the settlement of the support ,
A plurality of guide passages for passing the pile;
A center axis of the plurality of guide passages is inclined so as to be away from the tunnel center as it goes downward,
A central axis of at least two of the plurality of guide passages is inclined with respect to a vertical plane perpendicular to the tunnel depth direction, and extends obliquely downward in the excavation direction;
The central axes of the at least two guide passages have different inclination angles with respect to a vertical plane perpendicular to the tunnel depth direction when viewed from the side and above the tunnel, and when viewed from the tunnel depth direction and from above, A guide member for a pile guide, wherein the inclination angles with respect to a vertical plane extending in the depth direction of the tunnel are different from each other . A plate-shaped guide member that is horizontally fixed to a tunnel support leg and guides a pile for suppressing settlement of the support work ,
Having three or more guide passages for passing the pile;
The central axis of all guide passages inclines away from the tunnel center as it goes downward, and extends obliquely downward in the excavation direction,
The central axes of all the guide passages have different inclination angles with respect to a vertical plane perpendicular to the tunnel depth direction when viewed from the side and the upper side of the tunnel, and when viewed from the tunnel depth direction and the upper side , A guide member for a pile guide, wherein the inclination angles with respect to a vertical plane extending in the depth direction are different from each other. By fixing the guide member according to claim 1 or 2 only on the excavation direction side of the leg portion of the support work, and inserting the pile into each of the guide passages of the guide member to embed it in the ground A tunnel ground support method characterized by supporting the ground in front of the excavation direction.

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