KR101834847B1 - Echo-environmental construction method of tunnel portal area using mini pipe-roof - Google Patents

Abstract

The present invention provides an environmentally-friendly method to construct a portal part of a tunnel using a mini pipe-roof. According to the present invention, since a high strength mini pipe-roof is previously constructed on the outside of a tunnel excavation line at long depth while a natural slope of a tunnel portal part is kept without excavation, stability of the tunnel portal part is secured, and then a cross section of a tunnel is excavated to exclude or minimize a cut-off area of the tunnel portal part, thereby not generating earth construction of the tunnel portal part. Moreover, before excavation of the tunnel, the mini-pipe roof is previously and horizontally constructed on the natural slope of the tunnel portal part in one or two stages on the outside of a tunnel excavation line at the long depth according to a ground condition, thereby largely improving strength characteristics of the ground around the tunnel by securing strength of the mini-pipe roof and sufficient grouting curing time; and using stability of the natural slope stabilized for a long period, the tunnel portal part is able to be continuously excavated without additional reinforcement to the tunnel portal part where the mini-pipe roof is installed. Moreover, to form the tunnel portal part required in accordance with a topology, a ground condition, a roof fall risk of a tunnel portal slope, tunnel door type, and the like of the tunnel portal part, an external free field of the mini-pipe roof is adjusted, and an apparatus to partially remove an upper part of a tunnel door steel rib for construction is applied; thereby being able to adjust a position of a cut-and-cover tunnel from the inside of the tunnel. According to the present invention, the method comprises a position selection step, a mini-pipe roof installation step, a steel rib installation step, a removal step, a concrete lining deposition step, and a backfilling step.

Description

TECHNICAL FIELD [0001] The present invention relates to an echo-tunnel construction method using a mini-pipe loop,

[0001] The present invention relates to a method of constructing an eco-friendly tunnel shaft, and more particularly, to a method of constructing an eco-friendly tunnel shank in which a high strength mini pipe- The present invention relates to an eco-friendly tunnel shank construction method using a mini-pipe loop that excludes or minimizes a shank cut-out area by excavating a tunnel section after stabilizing it by long depth.

In general, the planar and longitudinal alignment of tunnels are planned considering the purpose and geographical characteristics such as roads, railways, subways, waterways and communication facilities, and the entrance and exit shafts (or NATM point and end point) Is formed in a position where it is easy to secure stability by comprehensively considering the ground and toe conditions of the tunnel shaft according to the planned longitudinal line type.

1 is a view showing a structure of a tunnel shaft according to a domestic design standard.

As shown in FIG. 1, the tunnel section is composed of an open tunnel, a gantry structure, a tunnel shaft section, and a tunnel general section. In the entire tunnel section, the tunnel area is poor and the tunneling effect is highly expected (D) of the tunnels in the direction of the length of the tunnel, and the area of the topography (H) below 1.5D according to the domestic design standards. And the tunnel shaft section, and stipulates to secure stability by applying active reinforcement measures.

In particular, the existing tunnel shafts have the largest impact due to the earthquake due to large slope slope formation and rebound of the tunnel connection. In domestic design standards, stability against various static loads and seismic loads, It is stipulated that the tunnel slope tunnel installation and connection plan should be established through measures to stabilize the slope of the shaft section and appropriate structural design so as to be secured.

Therefore, in the conventional tunnel shaft forming technology, the slope of the shaft portion is cut at the position where the rock (soft rock and light rock) or the minimum weathered rock cover is secured in order to secure the stability and work site for tunnel excavation, Point and end point), and reinforced by large-diameter steel pipe reinforcement grouting to the outside of the tunnel excavation line.

2A and 2B are diagrams for explaining the problems of the design and construction method of the tunnel shaft according to the prior art. Figs. 2A and 2B are views for explaining problems of the tunnel shank portion design and construction method, And FIG. 2C shows that a cut-off retaining wall is provided as a solution to the problem caused by the design and construction techniques of existing tunnel shafts. Such a cut-off retaining wall has a problem of poor workability and economical efficiency.

Specifically, as shown in FIG. 2A, when the slope area of tunnel slope section slope excavation shows good ground conditions and a gentle slope of the terrain slope, the tunnel slope portion design and construction method are applied, Although the tunnel slope slope and tunnel stability and construction are all secured, the field condition of the actual tunnel shafts is more likely to occur due to the condition of the distribution of the soil and weathered rock distributed in the steep slope, the superficial slope topography and the deep depth, exist.

As shown in FIG. 2C, when the slope slope and the slope retaining wall are formed in the tunnel shaft portion, there is a risk that the slope falls and slopes down during operation of the sliced retaining wall, which is very poor in terms of maintenance, There is a problem in that it is very poor in terms of safety of vehicle operation.

Further, as shown in Fig. 2 (d), as shown in Fig. 2 (d), a tunnel and a tunnel in which an unlimited sloping slope is generated due to a rapid terrain inclination of a tunnel portion connected to a bridge and a covered soil section by a linearization of a recent linear plan, In the case of tunnels in which the slope slope is difficult to form due to the existence of a slope (housing, housing, cultural properties, etc.), slope slope of the tunnel shaft portion should be excessively cut when a conventional shank part design and construction method is applied, and slope reinforcement and slope- Etc., the damage to the surrounding environment is large and the workability and economical efficiency are very poor.

FIG. 3 is a schematic view for explaining a large-diameter (straight-through) steel pipe reinforcing grouting method according to the prior art, wherein FIG. 3 (a) is a perspective view and FIG. 3 (b) is a side view.

As shown in Figs. 3 (a) and 3 (b), the tunnel shank is deeply dispersed in the soil and weathered rock layers having poor strength and deformation characteristics of the ground due to continuous weathering, Large-diameter steel pipe reinforced grouting (10) is installed in the ground outside the tunnel excavation line at 6.0 m intervals in the longitudinal direction. As a result, the excavation process is complicated by the additional construction process such as drilling of the large diameter steel pipe 10, injection of the injection material, and curing, so that the construction efficiency And the construction period is increased.

Considering the construction conditions of the site where the sufficient curing time of the large-diameter steel pipe reinforced grouting (10) can not be ensured, excessive grouting was performed during the tunnel excavation despite the construction of the large- And stress relieving due to stress concentration.

As a prior art, Korean Patent Laid-Open Publication No. 2005-66024 discloses an invention entitled " a method of constructing a direct-excavated tunnel shafts, "but the structure carbon steel pipe and the removal anchor are used to cut Can be minimized.

However, according to the conventional construction method of direct-excavation tunnel shafts, it is necessary to 1) increase the extension of the carbon steel pipe for the mild terrain structure, 2) to install the anchor of the tunnel shaft and to remove the weathered rock foundation , 3) it is difficult to form a shank tuning tunnel, and 4) grouting of steel pipe reinforcement needs to be augmented stepwise in the tunnel section of the shaft.

Specifically, (1) the problem of increasing the extension of the carbon steel pipe for mild terrain structure is that the installation time of the carbon steel pipe is long and the risk of structural stability deterioration is high when the hypothetical theory for carbon steel pipe is installed in a gentle tunnel shaft. will be. 2) The problem that it is difficult to install the anchor of the tunnel slope soil and the weathered rock foundation is that the removal anchor to fix the hypothetical specimen for the carbon steel pipe to the slope natural slope, It is difficult to exert an anchor force, and it is very disadvantageous in terms of workability and economical efficiency due to the problem of being fixed at a deep depth in order to exert the design anchor force. 3) It is difficult to form a tunnel opening tunnel. It is difficult to secure a foundation supporting force and a settlement stability as a form of a tunnel foundation formed on the soil and weathered portion, and the tunnel shaft portion of the whole tunnel section Since the seismic performance should be secured, if the main line tunnel concrete lining is extended to the shank, it is disadvantageous in terms of structural stability and seismic design is not possible by design criteria. 4) In order to install step-by-step steel-reinforced grouting for the 2.0D area (L = 20.0 ~ 30.0m) of the tunnel shaft part, the problem of reinforcing the steel pipe reinforcement grout step by step in the tunnel part of the shaft part, The tunnel construction must be stopped and thus the workability is disadvantageous.

On the other hand, Korean Patent Registration No. 10-1041301 discloses an invention entitled "Tunnel Excavation Method ", which is a method of horizontally penetrating a support tube body to a rock portion on a natural slope of a tunnel shaft portion, It can be minimized by cutting.

However, in the case of the tunnel excavation method according to the related art, there is a problem that excavation plans based on the tunnel shaft topography and the tunnel linearization plan are excluded, intrusion equipment and large intrusion equipment are required, There is a problem that it is difficult to secure the basic supporting force, and the actual design and construction such as difficulty in securing the basic supporting force are difficult.

As another prior art, Korean Patent No. 10-121643 discloses an invention entitled " environmentally friendly tunneling method ", which is characterized in that the slope slope of a tunnel shaft portion can be minimized by using a sheet file.

However, according to the eco-friendly tunneling method according to the related art, there is a problem that 1) the tunnel slope slope surface for setting the sheet pile guide is to be excavated, 2) the sheet pile is to be pushed in the horizontal direction, and 3) There is a problem that the structure of the main line concrete lining connection portion is weak.

Specifically, 1) the problem that the slope slope of the tunnel shafts for digging the sheet pile guide should be excavated, for example, in the case of a super-sloping slope, due to the tunnel slope slope excavation for the sheet- And the tunnel pillar portion is formed at a narrow position where the bridge and the embankment portion are connected to the tunnel, the actual application is very disadvantageous because the sheet pile guide can not be secured. 2) The problem of hitting the sheet file in the horizontal direction is that the actual sheet file can be hammered to the soil, but the hammering is not possible in the rock over the weathered rock, and the large hammering device must be located behind the seat file guide The construction is very disadvantageous and there is a risk of construction during construction. Particularly, when the seat file is driven in the horizontal direction, it is difficult to secure the straightness and the construction efficiency may be very low. 3) The structural problem of the unfolding tunnel and the main-line concrete lining connection portion is that it is difficult to secure the foundation supporting force and the settlement stability in the form of the unfolded tunnel foundation formed in the soil and weathered portion. In addition, Since seismic performance is to be secured, it is disadvantageous in terms of structural stability because the main tunnel tunnel lining is extended to the shafts.

On the other hand, as another prior art, Korean Patent No. 10-1184255 discloses an invention entitled "Method of constructing a gangway tunnel structure and a steel plate structure used in the method" Shaped steel plate structure is inserted between the H-shaped steel beam guide in a state in which the guide is constructed by penetrating the steel girder beam ahead of the tunnel, so that the slip of the tunnel shaft can be minimized.

However, according to the conventional method of constructing a gangway tunnel structure, large equipment is required for installing an H-shaped steel beam guide and a steel plate structure (press-fitting), it is difficult to secure a work space for a narrow shaft portion, There is a problem in that the construction period due to the press-fitting of the steel is increased. Moreover, application of a large amount of steel is uneconomical, and it is difficult to secure the minimum section of the shaft of the shafts section and limitation in actual design and construction .

As another prior art, Korean Patent Registration No. 10-1665515 discloses an invention entitled " Method and structure for constructing a multi-stage tunnel with straight perforated steel pipe without cutting ground slab ", which uses a multi- It is possible to form the oblique slope without cutting, and will be described in detail with reference to Figs. 4 and 5. Fig.

FIG. 4 is a view for explaining a method of constructing a multi-stage tunnel construction of a seamless perforated steel pipe without cutting a paperboard according to a conventional technique, and FIG. 5 is a view showing a multi-stage tunnel construction of a seamless perforated steel pipe shown in FIG.

4, a method for constructing a multi-stage tunnel construction of a seamless perforated steel pipe without cutting a ground sheet according to a conventional technique comprises the steps of: a) forming a foundation (21), a weathering layer (22) 20) in the form of a tunnel; b) inserting the steel pipe (30) to the rock layer by perforating the marked holes at the drilled holes; c) grouting the ground (20) using a steel pipe (30); d) extending the steel pipe (30) to the rear to protrude from the ground (20), and placing the rear ends of the steel pipe (30) on a vertical plane; e) providing a steel support member (40) inside the steel pipe (30) and casting a shotcrete (50) inside the steel pipe (30) to integrate the steel pipe (30) and the steel support member (40); f) drilling the inner ground (20) of the steel pipe (30) to excavate the tunnel; g) installing the tunnel gate 60 at the rear end of the steel pipe 30 after excavating the tunnel; And h) installing the tunnel gate 60 and covering the exposed outer side of the steel pipes 30 and a portion of the ground 20, The toe of the shaft portion can be formed, and at the same time, the ground 20 can be compressed to secure the stability of the slope surface. In addition, by using the steel support 40 and the steel pipe 30 as a structure of the tunnel shaft, it is possible to prevent collapse and fall of the ground 20 in the tunnel shaft, to secure the construction of the tunnel shaft, 30 may have binding portions 31 on both sides thereof and are coupled to each other as shown in Fig. 5, so that the bonding strength between the steel pipes 30 can be increased.

However, according to the conventional technique, the method of constructing a multi-stage tunnel with straight perforated steel pipe without cutting the ground slab has the following problems: 1) to bind the intrusion steel pipe in the horizontal direction, 2) And 3) it is not possible to secure the required thickness of the opening tunnel (500 mm or more).

Specifically, 1) the problem of transverse binding of the intrusion steel pipe is that the steel pipe of the straight grooved steel pipe reinforced grouting is dragged into the perforation hole by hanging from the straight drilling bit at the end of the steel pipe, and the penetration pressure can not be applied to the steel pipe , It is impossible to actually install the steel pipe binding apparatus because it requires a considerable penetration pressure load in order to penetrate the projected steel pipe binding apparatus into the shaft portion. In addition, the intrusion of the steel pipe in the shaft portion of the shaft by the steel pipe binding device causes the deformation of the steel pipe pre-established by the friction between the steel pipe itself and the binding device and the loosening of the ground around the steel pipe installation, Is very large. For example, the conventional multi-stage tunnel construction method of seamless perforated steel pipe without cutting ground slabs is applied to a tunnel shaft portion by applying a plurality of non-slip type construction methods. In the case of steel pipe deformation, There are actually many cases of settlement.

2) The problem of forming an extended tunnel section of the long extension by installing the gantry forklift in front of the building is due to an increase in the construction cost due to the extension of the entire tunnel, The location of the shafts to which the multi-stage tunnel construction method is applied is limited to the fact that the extension tunnel can not be formed long in the condition that the bridge and the embankment are connected with the tunnel. It is disadvantageous and it is difficult to secure the foundation supporting force and the settlement stability by forming the foundation of the unfolded tunnel on the soil and weathered rocks even if the unfolded tunnel can be formed long. In addition, in the method of constructing a multi-stage tunnel with straight perforated steel pipe without cutting the ground sheet according to the prior art, when a gantry such as a cylindrical incision, a bellmouth, a birdcage, There are limitations in terms of choosing gates to comply with negative topography and ground conditions.

3) The problem that the required tunneling thickness (500mm or more) can not be secured is due to the fact that the tunnels installed outside the tunnels are structures that receive direct external loads including seismic loads. Generally, The conventional technique has a problem in that it is difficult to secure the minimum required thickness of the tunnel and the amount of reinforcing steel reinforcement in the form of an extension of the section of the main line tunnel concrete lining (T = 300 mm) have.

Korean Patent Laid-Open Publication No. 2016-26343 (published on Mar. 9, 2016), entitled " Long Pipe Tube Punching Device for Improving Straightness and Mini Pipe Loop Construction Method Using the Same & Korean Patent No. 10-1665515 filed on Jan. 26, 2016, entitled "Method and structure for a multi-stage tunnel construction of a straight-perforated steel pipe without cutting ground, Korean Patent No. 10-1184255 filed on Dec. 14, 2011, entitled "Method of constructing a gangway tunnel structure and steel plate structure used in the method" Korean Patent No. 10-121643 filed on July 7, 2011, entitled " Environmentally Tunneling Method " Korean Patent No. 10-1041301 filed on July 29, 2010, entitled "Tunnel Excavation Method" Korean Unexamined Patent Publication No. 2005-66024 (Publication Date: June 30, 2005), entitled "

In order to solve the above-mentioned problems, a technical problem to be solved by the present invention is to provide a high-strength mini-pipe loop with a long slope outside the tunnel excavation shape, The present invention provides an eco-friendly tunnel shank construction method using a mini-pipe loop that excavates the shank portion continuously or excludes the shank cut-out area or minimizes the shank cut-off area.

Another object of the present invention is to provide a mini-pipe loop on a natural slope of a tunnel shaft with a horizontal directional depth to the outside of the tunnel excavation line in one or two stages before tunnel excavation according to the ground conditions, Strength and sufficient grouting By improving the strength characteristics of the ground around the tunnel by securing the curing time and taking advantage of the stability of the natural slope for a long period of time, it is possible to excavate the tunnel shaft without additional reinforcement in the shaft section of the mini- And to provide a continuous construction method of an eco-friendly tunnel shaft using a mini-pipe loop which can shorten the construction period.

Another object of the present invention is to adjust the external free length of a mini-pipe loop to form a required tunnel shaft according to the topography of the tunnel shaft, the ground condition, the risk of the slope descending slope, The present invention provides a method of constructing an eco-friendly tunnel shank using a mini-pipe loop in which the position of the unfolded tunnel can be installed inside the tunnel by applying a demolition device of the upper part of the river bank.

According to an aspect of the present invention, there is provided a method of constructing an eco-friendly tunnel shank using a mini-pipe loop, comprising the steps of: a) selecting a position of a tunnel shaft in consideration of a tunnel linear shape and a tunnel size; b) forming a vegetation-rich zone corresponding to the tunnel excavation area; c) constructing a mini-pipe loop on the outside of the tunnel excavation line to the planned depth considering the ground condition of the tunnel shaft to be buried without being exposed to the natural slope of the tunnel shaft; d) a tunnel shaft portion is drilled to the lower portion of the mini pipe loop to form an excavation region of the tunnel shaft portion, and a high strength steel beam for reinforcing a natural slope of the tunnel shaft portion is installed in the tunnel shaft excavation region, So as to be partially exposed; e) continuously excavating the step-by-step main tunnel and installing the support material; f) removing only the upper portion of the partially exposed gantry to meet the inclination of the natural slope of the tunnel shaft; g) casting a main tunnel tunnel concrete lining; And h) forming an unfolded tunnel and a gantry on the gantry for the construction of the demolished upper part, and laying backfill, wherein in the step c), while maintaining the natural slope of the tunnel shaft without excavation, In the step f), only the upper part of the gantry girder beam for construction is demolished by using the strong-ground beam removal device, and the tunnel tunnel is moved to the tunnel So that it can be adjusted inward.

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165㎜,

216㎜ 및

315㎜ 중에서 선택될 수 있다.Here, the length of the steel pipe of the mini-pipe loop in the step c) is 30 to 40 m, and depending on the size of the tunnel in the field and the load strength of the shaft portion,

165 mm,

216 mm and

315 mm.

In the step c), a mini-pipe loop is formed on the natural slope of the tunnel shaft part in a horizontal direction (L = 30.0 ~ 40.0m) on the outer side of the tunnel excavation line, To secure the stiffness of the high-strength mini-pipe loop and sufficient grouting curing time.

Here, in the step d), the tunnel shaft portion can be continuously excavated to the tunnel shaft portion where the mini pipe loop is installed, without additional reinforcement.

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Here, in step c), it is possible to adjust the outer free length of the mini-pipe loop to form a required tunnel shank according to the topography, ground conditions, slope descending risk of slopes and gantry type of the tunnel shank, Can be of any type, including face-to-face, cylinder-cut, bell mouth, and bead buck.

According to the present invention, a mini-pipe loop of high strength is held outside the tunnels excavation line at a longitude (L = 30.0 to 40.0 m) while securing the tunnel slope natural slope without excavation to secure the stability of the tunnel shaft , The tunnel cross section is continuously excavated to exclude or minimize the shaft cut area to avoid the occurrence of the shaft excavation. As a result, the design standard of the existing tunnel shaft section can be satisfied, Workability, shortening of air and economical efficiency can be ensured.

According to the present invention, a mini-pipe loop is provided on the natural slope of the tunnel shafts in a horizontal direction (L = 30.0 ~ 40.0 m) on the outer side of the tunnel excavation line in the first or second stage before tunnel excavation according to the ground conditions, Strength of the pipe loop and sufficient grouting By improving the strength characteristics of the ground around the tunnel by securing the curing time and taking advantage of the stability of the natural slope for a long period of time, the tunnel section of the tunnel without the additional reinforcement To improve the workability and shorten the construction period.

According to the present invention, in order to form a required tunnel shaft portion according to the topography of the tunnel shaft, the ground condition, the risk of falling down the slopes, and the type of gantry, it is necessary to adjust the outer free length of the mini- It is possible to adjust the position of the opening tunnel inside the tunnel.

1 is a view showing a structure of a tunnel shaft according to a domestic design standard.
FIGS. 2A to 2D are views for explaining the problems of the design and construction method of the tunnel shafts according to the related art.
FIG. 3 is a schematic view for explaining a conventional large-diameter (straight-through) steel pipe reinforcing grouting method.
FIG. 4 is a view for explaining a method of constructing a large diameter (straight perforated) steel pipe multi-stage tunnel without a ground cutting according to a conventional technique.
FIG. 5 is a view showing a construction of a multi-stage tunnel construction of a seamless perforated steel pipe without cutting of the paperboard shown in FIG.
6 is a schematic view for explaining a mini-pipe loop construction method according to an embodiment of the present invention.
7 is a view for explaining the comparison of the strength characteristics of the mini pipe loop method according to the embodiment of the present invention and the conventional large diameter (straight hole) grouting method.
8 is a view illustrating a tunnel constructed by an eco-friendly tunnel shank construction method using a mini pipe loop according to an embodiment of the present invention.
FIG. 9 is a flowchart illustrating a method of constructing an eco-friendly tunnel shank using a mini-pipe loop according to an embodiment of the present invention.
FIGS. 10 to 19 are views for explaining a method of constructing an eco-friendly tunnel shank using a mini-pipe loop according to an embodiment of the present invention.
FIGS. 20A to 20D are views for explaining conditions for installing a tunnelled inside tunnel in a method of constructing an eco-friendly tunnel shank using a mini-pipe loop according to an embodiment of the present invention.
FIGS. 21A to 20D are views for explaining conditions for installing tunnels outside the tunnels in a method of constructing an eco-friendly tunnel shank using a mini-pipe loop according to an embodiment of the present invention.
FIGS. 22A to 22D are diagrams for explaining conditions for installing the eccentric shafts in the eco-friendly tunnel shroud construction method using the mini-pipe loop according to the embodiment of the present invention, respectively.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

First, the pipe-roof method is a method of inserting and pushing a steel pipe along the circumference of the excavation section prior to excavation in a tunnel construction, or a method of supporting a tunnel in which a roof is formed in advance, And the excavation of the tunnel is supported. It is used for the construction of the tunnel near the shaft when constructing the tunnel under the existing railway, roads, and buildings by covering the shallow soil for the purpose of preventing settlement of the ground due to excavation of the tunnel, preventing loosening of the earthquake, and preventing collapse of the mining site. In addition, in the mountain tunnel, it is called a mini pipe loop in which a pipe of several meters in length is inserted along the outer circumference of the tunnel at the mining site to stabilize the mining site.

Specifically, the mini-pipe loop method is a method in which a steel pipe having a high rigidity in an arch shape or a column shape at regular intervals along the outer circumference of a main body structure, for example, a tunnel is directly inserted through a steel pipe before tunnel excavation, , The bending stiffness of high strength steel pipe, the strength characteristics of the improved ground, and the method of securing the stability by the support structure of the steel girder. For example, such a mini-pipe loop method may include a pre-arrangement, a door layout, a square layout, a straight layout, a column layout, and the like.

This mini-pipe loop method is characterized by resistance to the upper relaxation load due to the bending stiffness of the high strength steel pipe, the strength characteristics of the improved ground, and the support structure of the steel girder, and it is possible to improve the workability without the need for reaction wall and cross- At this time, it is possible to improve the stability and workability in the tunnel excavation and shorten the construction period by reinforcing the tunnel with the minipipe loop of the long hole.

According to this mini-pipe loop method, the cost of the unit of the applied steel pipe is increased slightly due to the increase of the stiffness. However, the actual cost of the tunnel is reduced due to the shortening of the tunnel construction cycle time and the additional reinforcement of the tunnel surface compared to the conventional multi- It is an environmentally friendly method because it can minimize slope slope of shaft part when selecting. According to this mini-pipe loop method, a steel pipe having a high rigidity as a long hole is installed in a shaft portion having a poor ground condition by a direct hole method, and grouting is performed to improve the strength characteristic of the ground around the tunnel. It is possible to secure sufficient stability during excavation of the shaft portion tunnel by exhibiting a composite support force with the steel girder beam installed during excavation.

This Mini-Pipe Loop method is used for the following purposes: 1) Perforated position survey, 2) Perforation and steel pipe insertion, 3) Visual inspection and internal measurement of steel pipe, 4) Packing installation, (Grouting) and finishing process. It is used for reinforcement at the passage of soft ground in tunnel mine, for reinforcing tunnel at tunnel shaft, for reinforcing connection to the subway and history in the inner city, for protecting and reinforcing superstructure foundation and structure, And for close tunnel reinforcement, it can be applied to tunnels of various ground conditions and construction conditions.

FIG. 6 is a schematic view for explaining a minipipe loop construction method according to an embodiment of the present invention, and FIG. 7 is a graph comparing strength characteristics of a mini pipe loop construction method according to an embodiment of the present invention and a conventional direct perforation large diameter grouting method Fig.

114㎜, t=6㎜ 및 L=12.0m이고, 도 6의 a) 및 b)에 도시된 바와 같이, 미니 파이프루프 공법은 강성이 큰 초대구경 강관을 종방향으로 길게 선보강하여 지반의 이완을 최소화하여 터널 안정성을 확보하는 공법으로서, 강관 제원은

165㎜,

216㎜ 및

1315㎜, t=7∼10㎜ 및 Lmax=30m(

165㎜), 40m(

216㎜ 및

1315㎜)이다. 이러한 미니 파이프루프 공법은 터널 갱구부에서 선보강한 후 터널을 연속적으로 굴착함에 따라 터널 굴착공정 단순화로 굴진효율이 증가되고 공사기간을 단축시킬 수 있다.The steel pipe of the large-diameter steel pipe reinforcing grouting method according to the prior art shown in FIG.

6 mm and L = 12.0 m. As shown in FIGS. 6 a) and 6 b), the mini-pipe loop method is a method in which a long rigid steel pipe having a large rigidity is long- As a method of securing the stability of the tunnel by minimizing it,

165 mm,

216 mm and

1315 mm, t = 7 to 10 mm and Lmax = 30 m (

165 mm), 40 m (

216 mm and

1315 mm). This mini pipe loop method can drastically increase the excavation efficiency and shorten the construction period due to the simplification of the tunnel excavation process by continuous excavation of the strong after tunnels at the tunnel shaft.

114㎜, t=6㎜(2열 중첩 보강)로서, 단면2차 모멘트는 600.4

이고, 강관의 휨강성은 1,260.9 kN·㎡로 주어진다. 이에 반해 미니 파이프루프 공법은

165㎜(t=7㎜, 1열 보강)인 경우, 단면2차 모멘트는 1,090.5

이고, 강관의 휨강성은 2,290.1 kN·㎡로, 전술한 대구경 강관 2열 대비 약 2.0배의 강성을 발휘하며,

216㎜(t=8㎜,1열 보강)인 경우, 단면2차 모멘트는 2,843.5

이고, 강관의 휨강성은 5,971.4 kN·㎡로, 전술한 대구경 강관 2열 대비 약 5.0배의 강성을 발휘하는 것을 알 수 있다.For example, as shown in FIG. 7, the conventional large-diameter steel pipe reinforcing grouting method

114 mm, t = 6 mm (two row superposition reinforcement), and the secondary moment of inertia is 600.4

And the flexural rigidity of the steel pipe is given by 1,260.9 kN · m 2. On the other hand,

165 mm (t = 7 mm, one row reinforcement), the secondary moment of inertia is 1,090.5

And the bending stiffness of the steel pipe is 2,290.1 kN · m 2, exhibiting a rigidity of about 2.0 times as large as that of the two large-diameter steel pipe described above,

216 mm (t = 8 mm, one row reinforcement), the secondary moment of inertia is 2,843.5

, And the bending stiffness of the steel pipe is 5,971.4 kN · m 2, which is about 5.0 times higher than that of the two large diameter steel pipes mentioned above.

114.3㎜) 2열 대비 미니 파이프루프의 강성이 2.0∼5.0배 큰 것을 알 수 있다. 특히, 보조공법 적용 대상지반이 그라우팅 효과를 크게 기대할 수 없는 조건일 경우, 강관의 강성이 보강효과 발휘에 가장 중요한 요소이고, 이에 따라 강관의 강성이 커서 보강효과가 크고 터널 굴진효율 측면에서도 유리한 미니 파이프루프를 적용하는 것이 바람직하다.As a result, as shown in FIG. 7, a comparison of the flexural strength of the steel pipe applied by the reinforcement method shows that the large-

114.3 mm) It can be seen that the stiffness of the mini pipe loop compared to the two rows is 2.0 to 5.0 times larger. Particularly, in the case where the ground to which the auxiliary method is applied can not expect the grouting effect, the rigidity of the steel pipe is the most important factor for exhibiting the reinforcing effect. Accordingly, It is desirable to apply a pipe loop.

Hereinafter, an eco-friendly tunnel shank construction method using a mini-pipe loop according to an embodiment of the present invention will be described with reference to FIGS. 8 to 22. FIG.

[How to construct eco-friendly tunnel shaft using mini pipe loop]

8 is a view illustrating a tunnel constructed by an eco-friendly tunnel shank construction method using a mini pipe loop according to an embodiment of the present invention.

8, the tunnels constructed by the eco-friendly tunnel shroud construction method using the mini pipe loop according to the embodiment of the present invention include a mini pipe loop 130, a high strength girder beam 150, a support 160 A plate 170, an anchor bolt 180, a concrete lining 190, an unfolding tunnel and a gantry 200, and a backfill material 210.

The tunnels constructed by the eco-friendly tunnel shoring method using the mini-pipe loop according to the embodiment of the present invention are constructed such that, in the tunnel construction, the minipipe roof 130 of high strength is fixed to the outside of the tunnel excavation shape And the tunnel cross section is continuously excavated to exclude or minimize the shank cut area so as not to generate the shank excavation.

In other words, a mini pipe loop (130) was installed on the natural slope of the tunnel shafts in a horizontal or vertical direction (L = 30.0 ~ 40.0 m) on the outer side of the tunnel excavation line in one or two stages before tunnel excavation according to the ground conditions. Since the stiffness of the pipe loop 130 and sufficient securing of grouting curing time are greatly improved and the stability of the natural slope stabilized for a long period of time is utilized, the length of the shaft portion (L = 30.0 ~ 40.0m), it is possible to improve the workability and shorten the construction period by continuously excavating the tunnel shaft without additional reinforcement.

The tunnels constructed by the eco-friendly tunnel shafts construction method using the mini pipe loop according to the embodiment of the present invention can be installed in various types of tunnel shafts in accordance with the topography of the tunnel shafts, the ground conditions, the risk of falling- The position of the unfolded tunnel can be easily adjusted inside the tunnel by adjusting the outer free length of the mini pipe loop 130 and applying the upper part demolition device 150 of the gentle sloping beam 150 to form the part.

FIG. 9 is a flowchart illustrating an operation method of an eco-friendly tunnel shroud construction method using a mini-pipe loop according to an embodiment of the present invention. FIGS. 10 to 19 are flowcharts of an eco- Fig. 8 is a view for explaining the auxiliary construction method in detail.

Referring to FIG. 9, in the eco-friendly tunnel shank construction method using the mini-pipe loop according to the embodiment of the present invention, first, the tunnel shaft position is determined considering the tunnel shape and the tunnel size, (S110). 10 (a) is a side view, and Fig. 10 (b) is a front view. The ground for forming the tunnels is ordinarily in the order of weathered soil, weathered rock and bedrock, and the vegetation area 110 is formed on the upper part , The location of the tunnel shaft is selected considering the tunnel type and the tunnel size.

Next, a vegetation-growing site 120 corresponding to the tunnel excavation area is formed (S120). 11 (a) is a side view, and FIG. 11 (b) is a front view showing a tunnel excavation area 120 by removing only the vegetation area 110 corresponding to the tunnel excavation area, Work can be excluded and minimized.

Next, as shown in FIGS. 12A and 12B, the tunnel shaft is to be embedded in the natural slope without being exposed to the natural slope. 130) (S130).

13 (a) and 13 (b), a tunnel shaft portion is drilled to the lower portion of the mini-pipe loop 130 to form a tunnel shaft excavation region 140, and a tunnel shaft excavation region 140, a high strength steel beam 150 for reinforcement of a natural slope is installed on the tunnel slab portion 140 so that a construction gantry is partially exposed through the natural slope of the tunnel shaft portion S140. Thus, a tunnel shaft excavation region 140 is formed by excavating the tunnel shaft portion, and a construction gantry is constructed by the high strength steel beam 150.

Next, as shown in Figs. 14A and 14B, the main road tunnels are successively excavated and the support 160 is installed (S150). 14B, the section A-A shows a main-line tunnel in which the support 160 is installed, and a support 160 is installed at a lower portion of the mini-pipe loop 130. As shown in FIG. Therefore, it is not necessary to stop the tunnel excavation every 6.0m for the general steel pipe reinforcement grouting construction.

Next, as shown in FIGS. 15A and 15B, only the upper part of the partially exposed gantry is removed in accordance with the slope of the tunnel slope natural slope (S160). Specifically, as shown in Fig. 15 (b), the BB cross-section indicates that the tunnel shoring part construction gantry girder beam 150 having L = 3.0 to 5.0 m is to be removed. When installing the tunnels inside the main tunnel, Only the upper portion of the gantry girder beam 150 is removed. 16 (b) is a plan view of the plate 170 and the anchor bolts 180 (FIG. 16 (a)) installed at the lower portion of the steel girder 150 16 (c) specifically shows aa cross section shown in Fig. 16 (b). 17 (a) and 17 (b) show the cutting length of the steel girder 150 in the changing portion as the gantry for construction.

Next, as shown in Figs. 18A and 18B, the main tunnel tunnel concrete lining 190 is installed (S170). Specifically, the cross section C-C shown in Fig. 18 (b) shows that the concrete lining 190 is installed in the main tunnel.

Next, as shown in Figs. 19 (a) and 19 (b), the unfolded tunnel 200 and the gantry 200 are formed on the gantry for demolishing the upper part, and the rebate 210 is installed (S180). Concretely, the section D-D shown in FIG. 19 (b) shows that the concrete is laid to form the opening tunnel and the gates 210.

According to the eco-friendly tunnel shoring method using the mini-pipe loop according to the embodiment of the present invention, a high-strength mini-pipe loop is maintained at a long depth outside the tunnel excavation line while the natural slope of the tunnel shaft is maintained without excavation After securing the stability of the tunnel shaft, the cross section of the tunnel is continuously excavated to exclude or minimize the shaft section cut area to avoid the occurrence of the slip of the shaft, thereby satisfying the design standard of the existing tunnel shaft section. By using the equipment, it is possible to secure the stability of the shaft, the workability, the shortening of the air and the economical efficiency.

In addition, a mini-pipe loop on the natural slope of the tunnel shaft was connected to the outside of the tunnel excavation line in the horizontal direction (L = 30.0 ~ 40.0m) in one or two stages before the tunnel excavation according to the ground conditions. And sufficient grouting curing time, the stability of the ground around the tunnel is greatly improved, and the stability of the natural slope has been stabilized for a long time. Therefore, the tunnel shaft of the mini pipe loop is excavated continuously without additional reinforcement, And the construction period can be shortened.

In addition, according to the topography of the tunnel shafts, the ground conditions, the risk of slope descending slopes, and the type of gantry, it is necessary to adjust the external free length of the mini pipe loop and to apply the demolition equipment The position of the unfolded tunnel can be adjusted inside the tunnel.

Meanwhile, according to the method of constructing an eco-friendly tunnel shaft using a mini-pipe loop according to an embodiment of the present invention, the position of the unfolded tunnel can be adjusted according to the topography, construction conditions, and operation purpose of the tunnel shaft.

20A to 20D are views for explaining conditions for installing a tunnelled inside tunnel in a method of constructing an eco-friendly tunnel shank using a mini-pipe loop according to an embodiment of the present invention, wherein FIG. 20A is a plan view, 20C is a front view of the tunnel view, and FIG. 20D is a front view of the NATM view.

As shown in FIGS. 20A to 20D, as a condition for installing a tunnelled tunnel inside a main tunnel for applying an eco-friendly tunnel shank construction method using a mini-pipe loop according to an embodiment of the present invention, When the tunnels of the tunnel are secured by the steep slopes of the rock slopes and the stability of the rock slopes is secured, if it is necessary to secure the economical efficiency by reducing the tunnel length, A tunnelled tunnel can be installed inside the main tunnel.

FIGS. 21A to 21D are views for explaining conditions for installing tunnels outside the tunnels in a method of constructing an eco-friendly tunnel shafts using a mini-pipe loop according to an embodiment of the present invention, wherein FIG. 21A is a plan view, FIG. 21C is a front view of the tunnel view, and FIG. 21D is a front view of the NATM view.

As shown in FIGS. 21A to 21D, as a tunnel installation condition outside the main tunnel for applying the eco-friendly tunnel tunnel construction method using the mini-pipe loop according to the embodiment of the present invention, If the tunnel shaft is required to form a gentle slope with a gentle slope, a fall-off is expected during the operation of the tunnel, and a bird-beak gantry installation is required, and a bell mouth type gantry installation is required to suppress the occurrence of the atmospheric pressure Roads are planned to be located above tunnel shafts, and tunnels can be installed outside the main tunnels in special cases such as the need to extend the tunnels.

FIGS. 22A to 22D are views for explaining conditions for installing the eccentric shafts in the eco-friendly tunnel shank construction method using the mini pipe loop according to the embodiment of the present invention, wherein FIG. 22A is a plan view, FIG. 22B is a longitudinal section view , FIG. 22C is an AA sectional view, and FIG. 22D is a front view of a NATM view.

As shown in FIG. 22A, a mini pipe loop conforming to a superslanted terrain type is installed as a condition for forming a super thin thread shaft portion for applying an eco-friendly tunnel shank construction method using a mini pipe loop according to an embodiment of the present invention, By adjusting the extension of the tunnel, as shown in Fig. 22B, it can be seen that the sloped slope of the tunnel shaft portion is not formed.

As a result, according to the embodiment of the present invention, it is possible to construct a substantially environmentally friendly tunnel shaft section satisfying the design standard of the current tunnel shaft section, and it is possible to construct by the tunnel equipment which is actually operating in the domestic market, And the shortening of the air can be ensured. Further, the position of the unlocking tunnel can be provided both inside and outside the main tunnel according to the topography of the shafts, the construction conditions, and the purpose of the operation.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

110: Vegetation area
120: vegetation opening area
130: Mini pipe loop
140: Tunnel shaft excavation area
150: High-strength steel girder beam (gantry for construction)
160: Support material
170: Plate
180: Anchor bolt
190: Concrete lining
200: Opening tunnels and gates
210: backfill material

Claims (9)

a) selecting the position of the tunnel shaft considering the tunnel linearity and the tunnel size;
b) forming a vegetation opening area 120 corresponding to the tunnel excavation area;
c) constructing a mini pipe loop (130) in the vegetation opening area (120) with a straight hole on the outside of the tunnel excavation line up to a planned depth considering the ground condition of the tunnel shaft so that it is buried without being exposed to the natural slope of the tunnel shaft ;
d) a tunnel shaft portion is drilled to a lower portion of the mini-pipe loop 130 to form a tunnel shaft excavation region 140, and a high strength steel beam 150 for reinforcing a tunnel slope natural slope is formed in a tunnel shaft excavation region 140 A step of installing a construction gantry so as to partially expose a tunnel slope natural slope;
e) continuously drilling the step-by-step mains tunnel and installing the support material 160;
f) removing only the upper portion of the partially exposed gantry to meet the inclination of the natural slope of the tunnel shaft;
g) casting the main tunnel tunnel concrete lining 190; And
h) forming an unfolding tunnel and a gantry (200) on the upper part of the construction gantry demolished and laying backfill material (210)
In step c), while maintaining the tunnel slope natural slope without excavation, the mini-pipe loop 130 of high strength is pivoted to the outside of the tunnel excavation line at a long depth to secure the stability of the tunnel shank, , And only the upper part of the gantry girder beam (150) for construction is demolished by using a steel beam bobbin removing device to adjust the position of the opening tunnel to the inside of the tunnel. delete The method according to claim 1,
The length of the steel pipe of the mini pipe loop 130 in the step c) is 30 to 40 m, and it is determined according to the required strength according to the size of the tunnel in the field and the load

165 mm,

216 mm and

315 mm. ≪ RTI ID = 0.0 > 31. < / RTI > The method according to claim 1,
In the step c), a mini-pipe loop is installed on the natural slope of the tunnel shaft at the first or second stage before tunnel excavation according to the ground conditions. The tunnel is horizontally oriented (L = 30.0 ~ 40.0m) Wherein a rigidity of the pipe loop and a sufficient grouting curing time are ensured. The method according to claim 1,
Wherein the tunnels are continuously excavated in the tunnel shaft portion provided with the mini-pipe loop in the step d) without additional reinforcement. delete The method according to claim 1,
The external free length of the mini pipe loop 130 is adjusted in step c) in order to form a necessary tunnel shank in accordance with the topography of the tunnel shaft, the ground condition, the risk of the slope slope failure, and the gate type. Construction method of eco - friendly tunnel shaft using mini - pipe loop. 8. The method of claim 7,
Wherein the gantry type is capable of installing any type of gantry including a face wall type, a cylindrical incision type, a bell mouth type, and a bead buck type. A tunnel structure constructed by an eco-friendly tunnel shank construction method using the mini-pipe loop according to claim 1.

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