JPH0266296A - Construction of support for branch part in cylindrical wall body used in excavated hole covering work - Google Patents

Abstract

PURPOSE:To improve the operation efficiency by placing a support which supports the branching segments of a cylindrical wall body, between them and forming this support from a pair of support legs stuck to the branching segments. CONSTITUTION:Main wall parts 10, 10 are constructed in such a way that branching segments 11 are placed below a cylindrical wall body and RC segments 14 are tightened at the left and the right position of this segment 11 with bolts circumferentially. Then the segment 11 is set between the upper end parts of the main wall parts 10, 10 and the segment 14 of the main wall part 10 is bolted to the segment 11. Support legs 15, 16 are mounted to the segments 11, 11 placed on and under the cylindrical wall body via PC steel members 17, respectively and the base parts 15a, 16a of the upper and the lower support legs 16 are joined with each other via a joint tool 5. Thus the operability and the installation performance may be improved.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention is used for lining multiple drilled holes in which a plurality of drilled holes each having a circular cross section are formed such that their side portions overlap each other. The present invention relates to the structure of a branch support in a cylindrical wall assembled by segments.

"Prior Art" In recent years, a method called a rectangular special cross-section shield method has been used as a large-section shield method for constructing large-section tunnel structures such as railway tunnels. This construction method uses a shield excavator, which has a structure in which two cylindrical shield excavators are connected, to excavate the ground or the ground in a cross-sectional shape of two circles, with some of them overlapping. , RC segments are assembled on the inner surface of this excavated hole to form a cylindrical wall, and a plurality of these cylindrical walls are connected along the hole (primary lining), and the back side of the segment of this secondary lining. In other words, after filling the gap between the segment and the ground with a grouting material, concrete is rolled on the inner surface of the secondary lining (secondary lining), supporting the ground with them, and filling the specified area. It is said to constitute the sky.

Conventionally, as a cylindrical wall constructed by the above construction method, for example, the one shown in FIG. 5 is known.

The cylindrical wall shown in the figure has main walls 2, 2 each having a C-shaped cross section and an inverted C-shaped cross section by connecting arc-shaped RC segments 1, and between the upper ends of these main walls 2. and a branch R located above and below which connects the branch RC segments 3 and 3 between the lower ends.
A middle pillar 4 is built between the C segments 3, 3, and the eyeglass frame-shaped walls thus constructed are successively connected in the axial direction of the excavated hole.

RC segment 1 constituting the above-mentioned cylindrical wall body, branch part R
The C segment 3 and the middle pillar 4 are connected by bolts and nuts, and each of the above-mentioned members has a joint fitting 5.5 having a bolt insertion hole 5a formed as a connection part by the bolt and nut.
... is buried.

The branch RC segment 3 is integrally molded with concrete to have a Y-shaped appearance, and its specific configuration includes a base 3C with a square cross section whose end face is connected to the center column 4, and a base 3C that branches from this base 3C. and each end face is the main wall part 2
, 2 and connecting arms 3a, 3b having a rectangular cross section.

Here, among the two connecting arm parts 3a and 3b, the connecting arm part 3a is formed longer than the connecting arm part 3b, and
The connecting arm portion 3a has a distal end thereof extending in an arc shape with the same radius of curvature as the RC segment 1. Of the connecting arms 3a and 3b, one is long and the other is short, including segments 1.1..., branch segments 3, 3.
... are arranged in a staggered manner in the axial direction of the cylindrical wall (to distribute stress in the cylindrical wall by arranging them in a staggered manner).

"Problem to be Solved by the Invention" By the way, in constructing such a tubular wall for lining a double excavation hole, it is necessary to erect a middle pillar 4 between the branch segments 3. However, since the middle pillar 4 is larger than the segments forming the cylindrical wall, there is a problem in that it takes time and effort to assemble it.

Further, in the conventional cylindrical wall body, a branch segment 3 having a Y-shaped appearance is interposed between the segments l forming the main wall parts 2, 2, and a middle pillar 4 is arranged between these branch segments 3. Due to the positioning structure, the positional accuracy of the branch segment 3 is required, so there is also the problem that the workability is poor.

Furthermore, because the branch segment 3 has a structure in which three members such as the segments 1, 1 and the middle pillar 4 are connected to the connecting arms 3a+3b and the base 3a, the dimensional accuracy of the branch segment 3 itself must be good. However, there were problems such as high costs.

This invention was made in view of the above circumstances, and its purpose is to provide a cover for excavated holes that can be easily constructed on site, improve work efficiency, and reduce costs. An object of the present invention is to provide a structure for a branch support in a cylindrical wall for construction.

"Means for Solving the Problem" In order to achieve the above object, the present invention provides a structure in which a plurality of excavated holes having a circular cross section overlap each other with their side parts.
The inside of the formed multiple drill holes is made up of circular arc-shaped segments assembled along the inner surface of the drill holes, and branch segments interposed at the overlapped portions of the drill holes. In a wall lining, a support body for supporting the branch segments is arranged between the branch segments of the cylindrical wall body, and this support body is attached to a pair of supports that are respectively fixed to the branch segments. The supporting legs are formed into a Y-shape in appearance, consisting of a base and two connecting arms branching from one end of the base along the inner surface of the branch segment. The present invention is characterized by a structure in which the base portions of the support legs are interconnected.

Furthermore, in order to achieve the same objective, a wall may be interposed between the bases of the support legs to connect these bases.

"Function" By assembling arc-shaped segments along the inner surface of the excavation hole while interposing the branch segment in the overlapping part of the excavation hole, a frame-shaped cylindrical wall body is constructed, and the branch segments arranged opposite to each other are assembled. By fixing the connecting arms of the Y-shaped support legs along each of the segments and connecting the bases of the support legs, a support for supporting the bifurcation segment is constructed.

Further, by interposing a wall material between the bases of the support legs and further dividing the support, it becomes possible to cope with an increase in the size of the cylindrical wall.

In addition, when the support body is constructed, the branch part of the cylindrical wall lining the excavation hole has a double structure with the branch part segment and the connecting arm part of the support leg body, so its strength is improved. , it becomes possible to reinforce the branch part.

"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, this embodiment is applied to a cylindrical wall body for lining the inside of a double-drilled hole formed by two drilled holes with circular cross sections overlapping their side parts. An example of applying the invention is shown.

FIG. 1 and FIG. 2 show an embodiment of the lining tubular wall body according to claim 1, and this lining tubular wall body has two horizontal sides.
The main walls 10.10 are constructed with a C-shaped cross section and an inverted C-shaped cross section on the left and right sides of the continuous excavation hole, and the main walls 10.10 are constructed with a C-shaped cross section and an inverted C-shaped cross section. The main components are a branch segment 11.11 that connects the branch segments 2.11 and a support 12 having the structure according to the present invention, which is disposed between the branch segments 2.11.

The main wall portion 10 is formed by fastening a plurality of arc-shaped RC segments 14 of the same shape with bolts and nuts via joint fittings 5 embedded in the end faces of these segments. It is what it is.

Further, bolt insertion holes 5 are provided on both sides of the RC segment 14 as connection parts using bolts and nuts as in the conventional case.
Joint fittings 5, 5, . . . formed with a are buried therein. In the illustrated example, the RC segment 14 is shown as the segment forming the main wall portion 10, but the present invention is not limited to this, and the main wall portion 10 may be constructed of steel segments.

The branch segment 11 is formed into a U-shape in which a portion of the cylindrical wall is curved inward, so as to join the main wall portion 10.10, which has a C-shaped cross section and an inverted C-shaped cross section. has been
Further, in the upper and lower joining end surfaces joined to the main walls 10, 10, joint fittings 5 each having a bolt insertion hole 5a are embedded as a connection part using bolts and nuts.

In the illustrated example, joint fittings 5 for connecting the branch segments 2 to each other are also provided on both sides of the branch segment 11.
is buried.

The support 12 has upper and lower branch segments 11.11
These branch segments 11.1 are interposed between
1, in the embodiment, the upper and lower branch segments 11. It is mainly composed of a pair of support legs 15 and 16 that are fixed to the ll and connected to each other.

The support leg 15.16 has a base 15a.

16a, and two connecting arms 1 branching from one end of the base 15a and 16a along the inner surface of the branch segment ll.
It is formed into a Y-shaped appearance consisting of 5b and 16b,
Further, these support legs 15 and 16 are each made of concrete with reinforcing steel bars embedded inside.

The base portions 15a and 16a extend in a flat plate shape so as to partition between the left and right main wall portions 1O110, and their tip surfaces 15c and 16c are respectively the base portions 15a.

16a has an inclined surface that is obliquely inclined along the longitudinal direction, and is designed to provide good operability when connecting these parts.

Note that the tip surfaces 15c of these base portions 15a and 16a.

16c and both side surfaces (joint surfaces) are embedded with joint fittings 5 each having a bolt insertion hole 5a formed therein as a connection part for bolts and nuts.

On the other hand, the connecting arms 15b and 16b have their respective distal ends extending in an arc shape with a constant radius of curvature along the inner surface of the branch segment 11, and bolts and bolts are provided on their joint surfaces. A joint fitting 5 in which a bolt insertion hole 5a is formed is embedded as a connection part using a nut.

By the way, as a means for connecting the support legs 15, 16 and the branch segment 11, as shown in FIG. PC steel materials 17 are applied, and both ends of these PC steel materials 17 are connected to connecting arm portions 15.
16b and the inner surface of the branch segment 11, respectively, through fixing means such as a pressure grip.

Although the embodiment shows a method of connecting the support legs 15, 16 and the branch segment 11 using the PC steel material 17, the present invention is not limited to such means. For example, it is also possible to apply connection means such as joint fittings using bolts, nuts, etc.

Next, the function of the support structure configured as described above will be explained along with the method of constructing the lining cylindrical wall.

As shown in FIGS. 1 and 2, in order to construct the cylindrical wall, the branch segment 11 is first placed below the cylindrical wall, and the branch segment 11 is The main wall 10.10 is constructed by sequentially bolting the left and right RC segments 14 in the circumferential direction, and then the branch segment 11 is connected between the upper ends of the main walls 10, 10.
The RC segment 14 of the main wall portion 10 and the branch segment 11 are connected by bolts.

Then, the branch segment located above and below the cylindrical wall body) 1
1.11, the support legs 15 and 16 are attached with P (JM material 17, and the bases 15a of these upper and lower support legs 16,
When the 16a are connected to each other via the joint fittings 5, the cylindrical wall body shown in FIG. 2 etc. is completed.

In this construction, the branch segments 11 are first placed from below the cylindrical wall, the main wall 10 is assembled while connecting the RC segments 14, the branch segments 11 are assembled on top of this, and then the support After connecting the legs 15, 16 to the upper and lower branch segments) 11.11, these bases 15a.

This is the work of connecting the parts 16a with bolts and bolts, and since each member is precast molded to a certain standard and size, the workability and construction efficiency can be improved.

In particular, the support 12 supporting the branch segment t 1.1 t is formed by a pair of support legs 15 , 16 which are connected and fixed to the upper and lower branch segments 11 , 11 , and which The bodies 15 and 16 are constructed by attaching PC steel 1 to these branch segments t 1,1 i after assembling the branch segments 11.11 to the main wall 10.10.
7, it can be easily installed, so there is an advantage that assembly work can be easily carried out on site.

Furthermore, since these support legs 15 and 16 have a separate structure from the branch segment 11.11, after the cylindrical wall is assembled into a frame shape, the support legs 15 and 16 are provided with support inside the cylindrical wall. Since the positions of the legs 15 and 16 can be easily adjusted, there is an advantage that the workability can also be improved.

Thus, in a cylindrical wall constructed in this way, the supports 12 are arranged between the branch segments 11.11 and these branch segments 1-11.11 are connected to the cylindrical wall. It can be supported from the inside, and the branch of the cylindrical wall can be supported by the branch segment 11 and the support leg 15. ．．
Since it can be double-reinforced by the 16 connecting arms 15a, 16a, the strength of the branch part can be improved and a strong cylindrical wall body can be constructed.

Moreover, FIG. 3 and FIG. 4 show an embodiment of the lining cylindrical wall body according to claim 2.

This lining tubular wall body has a wall structure between a pair of support legs 15A and 16A, instead of the support body 12 having a two-part structure consisting of a pair of support legs 15 and 16 shown in FIG. 20 is interposed between the branch segment 1 and the support body 12A.
1.11.

The wall material 20 is formed into a flat concrete plate with necessary reinforcing reinforcing bars embedded inside, and
Needless to say, each joint end face is provided with a joint fitting 5 in which a bolt insertion hole 5a is formed as a connection part for bolts, nuts, etc.

It should be noted that even in a cylindrical wall body equipped with such a support body 12A, substantially the same effects as those of the previous embodiment can be obtained, and in addition, the support body 12A can be used as a support leg body 15A, 16A, and a wall material 20. Since it is composed of three members, each member can be made smaller, making it easier to transport and assemble on site.As a result, when the cylindrical wall becomes larger, the workability is improved. It has the advantage of being able to improve further.

In each of the illustrated examples, a segment having a structure in which a part of the concrete body is curved in a U-shape is used as the branch segment 11, but the present invention applies to the branch segment I- It is not limited to 1, 1, but one of the upper and lower branch segments is formed into a small U-shape, and the other is thick (using the formed pair of branch segments, these can be connected to the main wall). 10.10, and the segments may be arranged in a staggered manner.

"Effects of the Invention" As explained above, according to the structure of the branch support in the cylindrical wall for lining an excavation hole according to the present invention, the following various excellent effects can be achieved.

(1) The present invention as set forth in claim 1 is a method for assembling the inside of a multiple drill hole, which is formed by a plurality of drill holes having a circular cross section and overlapping their side portions, along the inner surface of the drill hole. In the case of lining with a cylindrical wall body consisting of a circular arc-shaped segment and a branch segment interposed at the overlapped part of the excavation hole, there are A support for supporting the bifurcation segment is arranged, and the support comprises a pair of support legs each fixed to the bifurcation segment, and the support legs are connected to a base and one end of the base. The supporting legs are formed in a Y-shape in appearance, consisting of two connecting arms branching out along the inner surface of the branching segment, and the bases of the supporting legs are interconnected.
After constructing the frame-shaped cylindrical wall body, a support body can be assembled inside the frame-shaped cylindrical wall body, and its workability can be improved.

Particularly, according to the present invention, the branch segment is supported by assembling the Y-shaped support leg to the cylindrical wall, so the position of the support leg is determined separately from the branch segment. Can be adjusted and installed,
Workability on site can be improved.

In addition, when the support body is constructed, the branch part of the cylindrical wall lining the excavation hole has a double structure with the branch part segment and the connecting arm part of the support leg body, so its strength is improved. , it also has the advantage of making it possible to reinforce the branch section.

(2) In the structure of the branch support body of the present invention according to claim 2, a wall body connecting the base parts is interposed between the base parts of the support leg bodies, so that the support body is further divided into smaller parts. Since the structure is formed, it is possible to downsize the members constituting the support body, and there are effects such as ease of construction on site and improvement of work efficiency.

Particularly, according to the present invention as set forth in claim 2, there is an excellent advantage that the applicability when the cylindrical wall body is increased in size can be improved, and the workability thereof can be further improved.

(2) Furthermore, according to the present invention, the structure of the branch portion of the cylindrical wall body can be simplified, so there is an advantage that costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 show an example of the structure of the branch part support body in the lining tubular wall body according to claim 1,
Figure 1 is a perspective view showing the state in which the lining cylindrical wall body is constructed;
FIG. 2 is a front view thereof, FIGS. 3 and 4 show an example of the structure of the branch part support body in the lining tubular wall body according to claim 2, and FIG. 3 is a front view of the lining. FIG. 4 is a perspective view showing a state in which the cylindrical wall for lining has been constructed, FIG. 4 is a front view thereof, and FIG. 5 is a front view showing an example of the structure of a conventional cylindrical wall for lining. 5... Joint fitting, 5a... Bolt insertion hole, 10... Main wall, 11... Branch segment, 12... Support body, 14...RC segment, 15.16... Support leg body, 15A, 16A... Support leg body, 15a, 16a
...Base, 5b, 16b...Connecting arm portion 7...PC steel material, 8...Fixing hole, 0...Wall body.

Claims (1)

[Scope of Claims] 1) A circular arc assembled along the inner surface of the drilled hole, which is formed by a plurality of drilled holes having a circular cross section and overlapped with each other on their sides; In the case where the lining is made of a cylindrical wall body consisting of a plate-shaped segment and a branch segment interposed at the position of the overlapped part of the excavation hole, there are A support is disposed for supporting the bifurcation segment, and the support includes a pair of support legs each secured to the bifurcation segment, and the support legs extend from the base and one end of the base. The excavation is characterized in that it is formed in a Y-shape in appearance and consists of two connecting arms branching along the inner surface of a branch segment, and that the bases of the support legs are interconnected. Structure of a branch support in a cylindrical wall for lining a hole. 2) The structure of a branch support in a cylindrical wall for lining an excavated hole according to claim 1, characterized in that a wall is interposed between the bases of the support legs to connect these bases. .