JP3580381B2

JP3580381B2 - Pre-installation method of tunnel and its supporting method

Info

Publication number: JP3580381B2
Application number: JP01508295A
Authority: JP
Inventors: 善文田口; 昌男相良
Original assignee: Fujita Corp
Current assignee: Fujita Corp
Priority date: 1995-02-01
Filing date: 1995-02-01
Publication date: 2004-10-20
Anticipated expiration: 2019-10-20
Also published as: JPH08210079A

Description

【０００１】
【産業上の利用分野】
本発明は軟弱な地山からなる都市トンネルを掘削するのに当って、切羽前方の地山の補強工事を施工した場合の都市トンネルを効率よく施工するための先受工法及びその支保工法に係るものである。
【０００２】
【従来の技術】
切羽前方の補強方法として、本出願人は特開平５−１２５８９３号公報において、Ｔ字状の３方向を向いたものが２連配置された外周噴射ノズルａと先端噴射ノズルａとを具えた注入ロッドｂを所定の地盤に貫入し、前記各ノズルａより同時に水ガラスＡ、セメントミルクＢ等の瞬結性薬液を噴射するとともに、同各薬液噴射流のまわりに圧縮空気吐出口Ｃによって圧縮空気を連行させながら、注入ロッドｂを地盤から徐々に引き抜く地盤改良工法を提案した。（図６参照）
また従来の切羽地山の補強方法としてはパイプルーフやフォアパイリング工法が採用されていた。
【０００３】
図３は従来工法の一例を示す縦断面図で、切羽ｐ前方の地山をパイプルーフやフォアパイプｑによって補強するもので、図４は図３の掘削が完了した任意部分の先受工及び支保工を含むトンネルの断面を示し、ｒは支保工を示す。
図５は従来工法の他の例を示し、掘削が完了した任意部の先受工及び支保工ｒを含むトンネルの断面図である。
【０００４】
図４及び図５から明らかなように支保工ｒのサイズが掘削の進行に伴って大きくなる。図中ｓは逆Ｔ型固結体である。
【０００５】
【発明が解決しようとする課題】
前記従来の先受工は、施工機械が空間的制約を受け、各先受工をトンネル方向に重ね合わせる必要があるため、トンネル掘削方向に対して斜め上方に一定の勾配を以って施工される。
従ってトンネルの支保工は先受工の勾配に応じて各種のサイズの支保工を用意しておかなければならず、また勾配をつけることによって覆工コンクリートが余計に必要となる。
【０００６】
本発明は前記従来技術の有する問題点に鑑みて提案されたもので、その目的とするところは、施工性、経済性が向上され、施工管理が容易なトンネル先受工と支保工法を提供する点にある。
【０００７】
【課題を解決するための手段】
前記の目的を達成するため、本発明に係るトンネル先受工法によれば、Ｔ字状の３方向を向いたものが２連配置された外周噴射ノズルと先端噴射ノズルとを具えた注入ロッドによって、トンネル切羽前方の地山を所定の深さまで削孔したのち、同注入ロッドの前記先端噴射ノズルより瞬結性の地盤改良薬液を高圧噴射させながら同注入ロッドを地山から徐々に引き抜き、トンネル内空間側に脚部片が突出するようにＴ型固結体よりなる先受アーチを造成するものである。
【０００８】
また本発明に係るトンネル支保工法によれば、前記先受工法によってＴ型固結体よりなる前記先受アーチを造成したのち、同固結体の突出脚部片の一部分を地山とともに計画断面まで掘削し、支保工を建て込むものである。
【０００９】
【作用】
本発明によれば前記したように、Ｔ字状の３方向を向いたものが２連配置された外周噴射ノズルと先端噴射ノズルとを具えた注入ロッドによって、トンネル切羽前方の地山を所定の深さまで削孔し、しかるのち同注入ロッドの前記先端噴射ノズルより瞬結性の地盤改良液を高圧噴射させながら同注入ロッドを地山から徐々に引き抜くことによって、トンネル内空間に脚部片が突出するようにＴ型固結体より構成された先受工のアーチが造成される。
【００１０】
本発明に係る支保工法によれば前記先受アーチの突出脚部片の一部分を地山とともに設計断面まで掘削し、同じサイズの支保工を容易に建て込むことが可能である。
【００１１】
【実施例】
以下、本発明を図示の実施例について説明する。
図１及び図２に示す実施例において、Ｔ字状の３方向を向いたものが２連配置された外周噴射ノズルと先端噴射ノズルとを具えた注入ロッドによって、トンネル切羽１の前方の地山を所定の深さまで削孔したのち、同注入ロッドの先端噴射ノズルより水ガラス及びセメントミルク等の瞬結性地盤改良薬液を高圧噴射させながら同注入ロッドを地山から徐々に引き抜き、トンネル内空間側に脚部片２ａが突出するようにＴ型固結体２よりなる先受工のアーチを造成する（図２参照）。
更に支保工３を建て込む際には、前記Ｔ型固結体２の突出脚部片２ａの一部分を地山とともに設計断面４まで掘削し、支保工３を建て込む。
【００１２】
図２は本発明の方法によってトンネルを掘削したのち、支保工３を建て込んだときのトンネル任意区間の断面を示し、支保工３と同一サイズの支保工を容易に建て込むことができることを示している。
【００１３】
【発明の効果】
本発明によれば前記したように、Ｔ字状の３方向を向いたものが２連配置された外周噴射ノズルと先端噴射ノズルとを具えた注入ロッドによって、トンネル切羽前方の地山を所定の深さまで削孔したのち、同注入ロッドの前記先端噴射ノズルより瞬結性の地盤改良薬液を高圧噴射させながら同注入ロッドを地山から徐々に引き抜き、トンネル内空間側に脚部片が突出するようにＴ型固結体よりなる先受アーチを造成するようにしたことによって、先受工のアーチを効率よく施工しうるものである。
【００１４】
また本発明の支保工法によれば、前記支保工法によってＴ型固結体を造成したのち、同固結体の突出脚部片の一部分を地山とともに設計断面まで掘削し、支保工を建て込むことによって、トンネル支保工の先受工の勾配に応じて各種のサイズの支保工を用意する必要がなく、施工管理が容易になり、また掘削断面が上向き勾配をつける必要がなく、覆工コンクリートも設計量で十分であり、本発明によればこのように施工性、経済性が向上され、施工管理が容易なトンネル先受工及び支保工法が提供される。
【図面の簡単な説明】
【図１】本発明の方法によってトンネル切羽前方に造成された先受工及び支保工を含むトンネル全体の縦断面図である。
【図２】本発明の方法によって掘削が完了した任意部分の先受工及び支保工を含むトンネルの断面図で、左半部は図１のＡ−Ａ’断面図、右半部は図１のＢ−Ｂ’断面図である。
【図３】従来工法の一例を示す縦断面図である。
【図４】図３の掘削が完了した任意部分の先受工及び支保工を含むトンネルの断面図で、左半部は図３のＣ−Ｃ’断面図、右半部は図３のＤ−Ｄ’断面図である。
【図５】従来工法の他の例を示し、任意部分の先受工及び支保工を含むトンネルの断面図で、左半部は図３のＣ−Ｃ’断面図、右半部は図３のＤ−Ｄ’断面図である。
【図６】従来工法の更に他の例を示す縦断面図である。
【符号の説明】
１切羽
２Ｔ型固結体
２ａ脚部片
３支保工
４設計断面[0001]
[Industrial applications]
The present invention relates to a pre-installation method and a supporting method for efficiently constructing a city tunnel in the case of digging a city tunnel consisting of a soft ground, when reinforcing the ground in front of the face is constructed. Things.
[0002]
[Prior art]
As a method of reinforcing the front face of the face, the present applicant has disclosed in Japanese Patent Application Laid-Open No. 5-125893 an injection having an outer peripheral injection nozzle a and a tip injection nozzle a in which two T-shaped ones oriented in three directions are arranged in two rows. The rod b penetrates into a predetermined ground, and simultaneously jets a flashing chemical such as water glass A and cement milk B from each of the nozzles a. And the ground improvement method of gradually pulling out the injection rod b from the ground while entraining. (See Fig. 6)
In addition, as a conventional method of reinforcing face mountains, a pipe roof or a fore-piling method has been adopted.
[0003]
FIG. 3 is a longitudinal sectional view showing an example of the conventional construction method, in which the ground in front of the face p is reinforced by a pipe roof or a fore pipe q. FIG. The cross section of the tunnel including the shoring is shown, and r indicates the shoring.
FIG. 5 shows another example of the conventional construction method, and is a cross-sectional view of a tunnel including precedent work and support work r at an arbitrary portion after excavation is completed.
[0004]
As is clear from FIGS. 4 and 5, the size of the support r increases as the excavation progresses. In the figure, s is an inverted T-type compact.
[0005]
[Problems to be solved by the invention]
In the conventional pre-construction, since the construction machine is subject to space restrictions and it is necessary to overlap each pre-construction in the tunnel direction, the pre-construction is performed with a certain gradient obliquely upward with respect to the tunnel excavation direction. You.
Therefore, it is necessary to prepare various types of supports for the tunnel support in accordance with the gradient of the pre-construction, and by adding the gradient, extra lining concrete is required.
[0006]
SUMMARY OF THE INVENTION The present invention has been proposed in view of the problems of the prior art, and has as its object to provide a tunnel pre-installation and support method that is improved in workability and economy, and facilitates construction management. On the point.
[0007]
[Means for Solving the Problems]
To achieve the above object, according to the tunnel destination受工method according to the present invention, the injection rod de equipped with the outer peripheral injection nozzle and a tip injection nozzle that faces the three directions of the T-shaped is arranged in duplicate gradually pull the result, after boring a tunnel face in front of the natural ground to a predetermined depth, the same injection rod while high-pressure injection of Madokayui of soil improvement chemical from the tip ejection nozzle of the injection rod from the natural ground it is intended to construct a previously received arches made of T-type solid body as leg piece protrudes into the tunnel space side.
[0008]
According to the tunnel支保method according to the present invention, after the reclamation of the destination receiving arch made of T-type solid bodies by the destination受工method, a first portion of the protruding leg piece of the consolidated body with natural ground plan Excavation is performed to the section, and a shoring is built.
[0009]
[Action]
As described above, according to the present invention, depending on the injection rod de equipped with a T-shaped outer peripheral injection nozzles and a distal injection nozzle 3 that faces the direction is arranged duplicate, natural ground tunnel switching Uzen side by pulling gradually and boring to a predetermined depth, the same injection rod while high-pressure injection of Madokayui of soil improvement liquid from the destination Tan噴 morphism nozzle of the injection rod after accordingly from natural ground, tunnels sky arch previously受工constructed from T-type solid body is construction as leg piece protrudes between.
[0010]
One portion of the protruding leg piece of the destination receiving arch according to支保method according to the present invention was drilled to a designed cross-section with the natural ground, which is the支保Engineering of the same size can be easily Tatekomu.
[0011]
【Example】
Hereinafter, the present invention will be described with reference to the illustrated embodiments.
In the embodiment shown in FIGS. 1 and 2, depending on the injection rod de equipped with a T-shaped outer peripheral injection nozzles and a distal injection nozzle 3 that faces the direction is arranged duplicate, the tunnel face 1 in front of After boring the natural ground to a predetermined depth, gradually pull the same injection rod while the Madokayui of ground improvement chemical water glass and cement milk or the like is high-pressure injection from earlier Tan噴 morphism nozzle of the injection rod from the natural ground , we construct a arch ahead受工consisting T-caking body 2 as leg piece 2a in the tunnel in the spatial side protrudes (see FIG. 2).
Further when Tatekomu the支保Engineering 3, one portion of the protruding leg piece 2a of the T-type solidifying body 2 and drilled to design sectional 4 with natural ground, Tatekomu the支保Engineering 3.
[0012]
FIG. 2 shows a section of an arbitrary section of the tunnel when a shoring 3 is erected after excavating a tunnel by the method of the present invention, and shows that a shoring of the same size as the shoring 3 can be easily erected. ing.
[0013]
【The invention's effect】
As described above, according to the present invention, depending on the injection rod de equipped with a T-shaped outer peripheral injection nozzles and a distal injection nozzle 3 that faces the direction is arranged duplicate, the tunnel face in front of the natural ground After boring to a predetermined depth, the tip Madokayui of soil improvement chemical from the ejection nozzle gradually pull the same injection rod while high-pressure injection from the natural ground and the leg piece in the tunnel space side of the injection rod By forming the precedent arch made of the T-type consolidated body so as to protrude , the precedent arch can be efficiently constructed.
[0014]
According to支保method of the present invention, the After construct a T-type solid sintered by支保method, drilling one portion of the protruding leg piece of the consolidated body to design cross with natural ground, built支保Engineering By doing this, it is not necessary to prepare various sizes of supports in accordance with the gradient of the pre-construction of the tunnel support, and the construction management becomes easy. The design amount of concrete is also sufficient, and according to the present invention, there is provided a tunnel tip receiving and supporting method in which the workability and economic efficiency are improved and the construction management is easy.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an entire tunnel including a precedent and a support formed in front of a tunnel face by a method of the present invention.
FIG. 2 is a cross-sectional view of a tunnel including excavation and support of an arbitrary portion where excavation is completed according to the method of the present invention. It is BB 'sectional drawing of.
FIG. 3 is a longitudinal sectional view showing an example of a conventional method.
4 is a cross-sectional view of a tunnel including excavation and support of an arbitrary portion after excavation of FIG. 3 is completed. A left half portion is a cross-sectional view taken along the line CC ′ of FIG. 3; It is a -D 'sectional view.
5 shows another example of the conventional method, and is a cross-sectional view of a tunnel including an arbitrary precedent work and a shoring method. The left half is a cross-sectional view taken along the line CC ′ of FIG. It is DD 'sectional drawing of.
FIG. 6 is a vertical sectional view showing still another example of the conventional method.
[Explanation of symbols]
1 Face 2 T type solid sintered body 2a leg piece 3支保Engineering 4 Design section

Claims

Thus the injection rod de to those facing three directions T-shape equipped with an outer peripheral injection nozzle and tip ejection nozzle disposed duplicate, after boring a tunnel face in front of the natural ground to a predetermined depth, the Madokayui of soil improvement chemical from the tip ejection nozzle of the injection rod is gradually pull the same injection rod while high-pressure injection from the natural ground and the T-type solid body as leg piece protrudes into the tunnel space side A pre-installation method for tunnels, characterized by the creation of a pre-support arch.

Thus the injection rod de to those facing three directions T-shape equipped with an outer peripheral injection nozzle and tip ejection nozzle disposed duplicate, after boring a tunnel face in front of the natural ground to a predetermined depth, the gradual withdrawal of the injection rod while high-pressure injection of Madokayui of soil improvement chemical from the tip ejection nozzle from the natural ground, T-type solid sintered body as leg piece protrudes into the tunnel space side of the injection rod After reclamation more made previously received arch, excavating the first portion of the protruding leg piece of the consolidated body to plan cross with natural ground,支保method of tunnel, characterized in that Tatekomu the支保Engineering.