CN212614721U

CN212614721U - Shield constructs steel negative ring structure that starts

Info

Publication number: CN212614721U
Application number: CN202020969213.6U
Authority: CN
Inventors: 赖泉昌; 冯德威; 华振; 李国华; 杨乾坤
Original assignee: CCCC First Highway Engineering Co Ltd; CCCC First Highway Xiamen Engineering Co Ltd
Current assignee: CCCC First Highway Engineering Co Ltd; CCCC First Highway Xiamen Engineering Co Ltd
Priority date: 2020-06-01
Filing date: 2020-06-01
Publication date: 2021-02-26
Anticipated expiration: 2030-06-01

Abstract

The utility model belongs to the technical field of tunnel construction, especially, shield structure steel burden ring structure of originating, including bottom standard block section of jurisdiction, first standard block section of jurisdiction and second standard block section of jurisdiction are installed respectively to the side about bottom standard block section of jurisdiction, first block section of jurisdiction and second adjacent block section of jurisdiction are installed respectively to the top of first standard block section of jurisdiction and the top of second standard block section of jurisdiction first adjacent block section of jurisdiction, first adjacent block section of jurisdiction and second adjacent block section of jurisdiction between installing and sealing a piece section of jurisdiction, bottom standard block section of jurisdiction, first standard block section of jurisdiction, second standard block section of jurisdiction, first adjacent block section of jurisdiction and sealing a piece section of jurisdiction's antetheca homogeneous body shaping has the grafting piece, this device can be carried out the staggered joint when installing between two sections burden ring structures through grafting groove and grafting piece The connection holes are aligned quickly.

Description

Shield constructs steel negative ring structure that starts

Technical Field

The utility model belongs to the technical field of tunnel construction, concretely relates to shield constructs steel negative ring structure of starting.

Background

The shield method is a fully mechanical construction method in the construction of the underground excavation method. The shield machine is propelled in the ground, and the surrounding rocks around the shield machine are supported by the shield shell and the duct pieces to prevent collapse into the tunnel. And simultaneously, excavating the soil body in front of the excavation surface by using a cutting device, conveying the soil out of the hole by using an excavating machine, jacking the soil body by pressing at the rear part by using a jack, and assembling precast concrete segments to form the mechanical construction method of the tunnel structure.

Compared with the prior art the problem that exists:

when the shield tunneling method is used for excavating a tunnel, an annular duct piece needs to be installed between a reaction frame and a shield jack when a shield tunneling machine starts to drive forward propelling acting force for the shield tunneling machine, connection between negative rings is connected and fixed in a staggered joint installation and connection mode under normal conditions, and connecting holes of the two negative rings are not easy to align when the two negative rings are installed in staggered joints, so that installation efficiency is affected.

SUMMERY OF THE UTILITY MODEL

To solve the problems set forth in the background art described above. The utility model provides a shield constructs steel negative ring structure of starting carries out quick alignment to its longitudinal connecting hole when setting up through inserting groove and grafting piece can carry out the stagger joint installation between two sections negative ring structures.

In order to achieve the above object, the utility model provides a following technical scheme: the utility model provides a shield constructs steel negative ring structure of originating, includes bottom standard block section of jurisdiction, first standard block section of jurisdiction and second standard block section of jurisdiction are installed respectively to the side about the bottom standard block section of jurisdiction, first block section of jurisdiction and second adjacent block section of jurisdiction are installed respectively to the top of first standard block section of jurisdiction and the top of second standard block section of jurisdiction, first adjacent block section of jurisdiction and second adjacent block section of jurisdiction between install the block section of capping piece section of jurisdiction, the left and right sides of block section of capping all inwards opens the block transverse connection hole that seals, both sides all inwards have the block longitudinal connection hole that seals around the block section of capping piece, the left and right sides of first adjacent block section of jurisdiction and second adjacent block section of jurisdiction all inwards open adjacent block transverse connection hole, first adjacent block section of jurisdiction and second adjacent block section of jurisdiction all inwards open adjacent block longitudinal connection hole that connects around, bottom standard block section of jurisdiction, The left and right sides of the first standard block pipe piece and the second standard block pipe piece are all inwards provided with standard block transverse connecting holes, the front and back sides of the bottom standard block pipe piece, the first standard block pipe piece and the second standard block pipe piece are all inwards provided with standard block longitudinal connecting holes, the front walls of the bottom standard block pipe piece, the first standard block pipe piece, the second standard block pipe piece, the first abutting block pipe piece, the second abutting block pipe piece and the top sealing block pipe piece are all inwards provided with inserting grooves, and the back walls of the bottom standard block pipe piece, the first standard block pipe piece, the second standard block pipe piece, the first abutting block pipe piece, the second abutting block pipe piece and the top sealing block pipe piece are all integrally formed with inserting blocks.

Preferably, four transverse connecting holes of the capping block, four transverse connecting holes of the adjacent block and four transverse connecting holes of the standard block are arranged, and two transverse connecting holes are arranged on the left side and the right side of each segment respectively.

Preferably, the longitudinal connecting holes of the capping blocks are two, and the front side and the rear side of the segment of the capping block are respectively provided with one.

Preferably, the adjacent block longitudinal connecting holes and the standard block longitudinal connecting holes are all provided with six, and the front side and the rear side of the first standard block pipe piece and the second standard block pipe piece, and the front side and the rear side of the first adjacent block pipe piece and the second adjacent block pipe piece are respectively provided with three.

Preferably, the cross section of the capping block pipe piece is isosceles trapezoid.

Preferably, the cross-sectional shapes of the first adjacent block pipe piece and the second adjacent block pipe piece are right-angled trapezoids.

Preferably, the number of the inserting grooves and the inserting blocks on the bottom standard block pipe piece, the first standard block pipe piece, the second standard block pipe piece, the first abutting block pipe piece, the second abutting block pipe piece and the capping block pipe piece is the same as the number of the standard block longitudinal connecting holes, the abutting block longitudinal connecting holes and the capping block longitudinal connecting holes which are positioned on the same side, and the standard block longitudinal connecting holes, the abutting block longitudinal connecting holes and the capping block longitudinal connecting holes are positioned on the same central axis.

Preferably, the other sides of the standard block transverse connecting hole, the abutting block transverse connecting hole, the capping block transverse connecting hole, the standard block longitudinal connecting hole, the abutting block longitudinal connecting hole and the capping block longitudinal connecting hole are communicated with the bolt through grooves, and the bolt is arranged on the inner side wall of the bottom standard block duct piece, the first standard block duct piece, the second standard block duct piece, the first abutting block duct piece, the second abutting block duct piece and the capping block duct piece through the grooves.

Compared with the prior art, the beneficial effects of the utility model are that: this device is through the setting of inserting groove and grafting piece, when carrying out the fissure of displacement installation with another section negative ring structure on one section negative ring structure of installing, each section of jurisdiction of the negative ring structure of will treating the installation aligns the insertion groove on its each section of jurisdiction and the grafting piece of each section of jurisdiction on the first section negative ring of installing with each section of jurisdiction of the first section negative ring of installing with the mode of fissure of displacement installation, can help it to fix a position the longitudinal connecting hole on each section of jurisdiction fast, make the standard block longitudinal connecting hole of two sections negative ring junctions, abut against a longitudinal connecting hole and carry out quick alignment with a longitudinal connecting hole of top sealing piece, use the standard block longitudinal connecting hole that the bolt will make two sections negative ring junctions, abut against a longitudinal connecting hole and a longitudinal connecting hole of top sealing piece and connect fixedly and can accomplish the connection between two sections negative ring structures and fix, and convenient and fast.

The parts of the device not involved are the same as or can be implemented using prior art.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view of the front cross-sectional structure of the present invention;

FIG. 2 is a schematic structural view of a capping segment, a first adjacent segment and a second adjacent segment of the present invention;

FIG. 3 is a schematic view of the structure of the bottom standard block segment of the present invention;

fig. 4 is the utility model discloses bottom standard block section of jurisdiction left side view cut-away schematic diagram.

In the figure: 11 bottom standard block pipe piece, 12 first standard block pipe piece, 13 second standard block pipe piece, 101 standard block transverse connecting hole, 102 standard block longitudinal connecting hole, 21 first abutting block pipe piece, 22 second abutting block pipe piece, 201 abutting block transverse connecting hole, 202 abutting block longitudinal connecting hole, 3 capping block pipe piece, 31 capping block transverse connecting hole, 32 capping block longitudinal connecting hole, 4 inserting groove, 5 inserting block, 6 bolt passing groove.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Example 1

Referring to fig. 1-4, the present invention provides the following technical solutions: a shield starting steel negative ring structure comprises a bottom standard block pipe piece 11, wherein a first standard block pipe piece 12 and a second standard block pipe piece 13 are respectively arranged on the left side and the right side of the bottom standard block pipe piece 11, a first adjacent block pipe piece 21 and a second adjacent block pipe piece 22 are respectively arranged on the top of the first standard block pipe piece 12 and the top of the second standard block pipe piece 13, a capping block pipe piece 3 is arranged between the first adjacent block pipe piece 21 and the second adjacent block pipe piece 22, capping block transverse connecting holes 31 are inwards formed in the left side and the right side of the capping block pipe piece 3, capping block longitudinal connecting holes 32 are inwards formed in the front side and the rear side of the capping block pipe piece 3, adjacent block transverse connecting holes 201 are inwards formed in the left side and the right side of the first adjacent block pipe piece 21 and the right side of the second adjacent block pipe piece 22, adjacent block longitudinal connecting holes 202 are inwards formed in the front side and the rear side of the first adjacent block pipe piece 21 and the second adjacent block 22, the left and right sides of the bottom standard block pipe piece 11, the first standard block pipe piece 12 and the second standard block pipe piece 13 are all inwards provided with standard block transverse connecting holes 101, the front and back sides of the bottom standard block pipe piece 11, the first standard block pipe piece 12 and the second standard block pipe piece 13 are all inwards provided with standard block longitudinal connecting holes 102, the front walls of the bottom standard block pipe piece 11, the first standard block pipe piece 12, the second standard block pipe piece 13, the first abutting block pipe piece 21, the second abutting block pipe piece 22 and the top sealing block pipe piece 3 are all inwards provided with inserting grooves 4, and the rear walls of the bottom standard block pipe piece 11, the first standard block pipe piece 12, the second standard block pipe piece 13, the first abutting block pipe piece 21, the second abutting block pipe piece 22 and the top sealing block pipe piece 3 are all integrally formed with inserting blocks 5.

In this embodiment: including bottom standard block section of jurisdiction 11, first standard block section of jurisdiction 12, second standard block section of jurisdiction 13, first adjacency block section of jurisdiction 21, second adjacency block section of jurisdiction 22 and block of capping section of jurisdiction 3, first standard block section of jurisdiction 12 and second standard block section of jurisdiction 13 are installed respectively to the left and right sides of bottom standard block section of jurisdiction 11, first adjacency block section of jurisdiction 21 and second adjacency block section of jurisdiction 22 are installed respectively to the top of first standard block section of jurisdiction 12 and the top of second standard block section of jurisdiction 13, block section of jurisdiction 3 is installed to first adjacency block section of jurisdiction 21 and second adjacency block section of jurisdiction 22, block transverse connection hole 31 is sealed to the left and right sides of block section of jurisdiction 3 all inwards opened, block longitudinal connection hole 32 is sealed to both sides around block section of jurisdiction 3, the left and right sides of first adjacency block section of jurisdiction 21 and second adjacency block section of jurisdiction 22 all inwards opened adjacency block transverse connection hole 201, both sides around first adjacency block section of jurisdiction 21 and second adjacency block 22 all inwards opened adjacency block longitudinal connection hole 202 The left and right sides of the bottom standard block pipe piece 11, the first standard block pipe piece 12 and the second standard block pipe piece 13 are all inwards provided with standard block transverse connecting holes 101, the front and back sides of the bottom standard block pipe piece 11, the first standard block pipe piece 12 and the second standard block pipe piece 13 are all inwards provided with standard block longitudinal connecting holes 102, the front walls of the bottom standard block pipe piece 11, the first standard block pipe piece 12, the second standard block pipe piece 13, the first adjacent block pipe piece 21, the second adjacent block pipe piece 22 and the capping block pipe piece 3 are all inwards provided with inserting grooves 4, the rear walls of the bottom standard block pipe piece 11, the first standard block pipe piece 12, the second standard block pipe piece 13, the first adjacent block pipe piece 21, the second adjacent block pipe piece 22 and the capping block pipe piece 3 are integrally formed with inserting blocks 5, the standard block transverse connecting holes 101 on two sides of the bottom standard block pipe piece 11 are respectively aligned with the standard block transverse connecting holes 101 on the right side of the first standard block pipe piece 12 and the left side of the second standard block pipe piece 13, bolts are inserted into the standard block transverse connecting holes 101 at the positions through the grooves 6 by bolts and tightened by nuts, so that the first standard block pipe piece 12, the bottom standard block pipe piece 11 and the second bottom standard block pipe piece 13 are fixed, a first adjacent block pipe piece 21 is arranged at the other end of the first standard block pipe piece 12, a second adjacent block pipe piece 22 is arranged at the other end of the second standard block pipe piece 13, the standard block transverse connecting hole 101 and the adjacent block transverse connecting hole 201 at the joint of the first standard block pipe piece 12 and the first adjacent block pipe piece 21 and the standard block transverse connecting hole 101 and the adjacent block transverse connecting hole 201 at the joint of the second standard block pipe piece 13 and the second adjacent block pipe piece 22 are aligned, the first standard block pipe piece 12 and the first adjacent block pipe piece 21 as well as the second standard block pipe piece 13 and the second adjacent block pipe piece 22 can be fixed by tightening the bolts, finally, the capping block pipe piece 3 is placed between the first adjacent block pipe piece 21 and the second adjacent block pipe piece 22, the capping block transverse connecting holes 31 on the left side and the right side of the capping block pipe piece 3 are respectively aligned with the adjacent block transverse connecting holes 201 on the right side of the first adjacent block pipe piece 21 and the left side of the second adjacent block pipe piece 22 and then are fixed through bolts, and therefore installation of one section of negative ring can be completed, the inserting block 5 is used for being connected with the inserting groove 4 and can help the inserting groove to be quickly positioned, the standard block longitudinal connecting holes 102, the adjacent block longitudinal connecting holes 202 and the capping block longitudinal connecting holes 32 at the joint of the two sections of negative rings are quickly aligned, and the standard block longitudinal connecting holes 102, the adjacent block longitudinal connecting holes 202 and the capping block longitudinal connecting holes 32 at the joint of the two sections of negative rings are connected and fixed through.

The capping block transverse connecting holes 31, the adjoining block transverse connecting holes 201 and the standard block transverse connecting holes 101 are four in number, and the left side and the right side of each segment are two in number.

Two longitudinal connecting holes 32 are formed in the top sealing block, and one longitudinal connecting hole is formed in the front side and the rear side of the top sealing block pipe piece 3, so that staggered joint installation can be conveniently conducted between the two sections of negative ring structures.

The adjacent block longitudinal connecting holes 202 and the standard block longitudinal connecting holes 102 are six, the front side and the rear side of the first standard block pipe piece 12 and the second standard block pipe piece 13 and the front side and the rear side of the first adjacent block pipe piece 21 and the second adjacent block pipe piece 22 are respectively provided with three, and staggered joint installation is conveniently carried out between two sections of negative ring structures.

The cross section of the capping block pipe piece 3 is isosceles trapezoid.

The cross-sectional shapes of the first adjoining block segment 21 and the second adjoining block segment 22 are right-angled trapezoids.

The number of the inserting grooves 4 and the inserting blocks 5 on the bottom standard block pipe piece 11, the first standard block pipe piece 12, the second standard block pipe piece 13, the first abutting block pipe piece 21, the second abutting block pipe piece 22 and the capping block pipe piece 3 is the same as that of the standard block longitudinal connecting holes 102, the abutting block longitudinal connecting holes 202 and the capping block longitudinal connecting holes 32 which are positioned on the same side, and the inserting grooves 4 and the inserting blocks 5 are positioned on the same central axis line, so that when two sections of negative rings are connected, the connecting positions of the two sections of negative rings can be aligned with the standard block longitudinal connecting holes 102, the abutting block longitudinal connecting holes 202 and the capping block longitudinal connecting holes 32 which are opposite to the connecting positions of the two sections of negative rings by inserting any inserting the inserting groove 4 and any inserting block 5.

The other sides of the standard block transverse connecting hole 101, the adjacent block transverse connecting hole 201, the capping block transverse connecting hole 31, the standard block longitudinal connecting hole 102, the adjacent block longitudinal connecting hole 202 and the capping block longitudinal connecting hole 32 are communicated with the bolt through a groove 6, the bolt is arranged on the inner side walls of the bottom standard block pipe piece 11, the first standard block pipe piece 12, the second standard block pipe piece 13, the first adjacent block pipe piece 21, the second adjacent block pipe piece 22 and the capping block pipe piece 3 through the groove 6, the bolt can be inserted into the standard block transverse connecting hole 101, the adjacent block transverse connecting hole 201, the capping block transverse connecting hole 31, the standard block longitudinal connecting hole 102, the adjacent block longitudinal connecting hole 202 and the capping block longitudinal connecting hole 32 through the groove 6, and the pipe pieces and negative rings of different sections are connected and fixed.

The working principle and the using process of the invention are as follows: the device firstly installs the bottom standard block pipe piece 11, respectively aligns the standard block transverse connecting holes 101 at two sides of the bottom standard block pipe piece 11 with the standard block transverse connecting holes 101 at the right side of a first standard block pipe piece 12 and the left side of a second standard block pipe piece 13, inserts bolts into the standard block transverse connecting holes 101 at the positions through a groove 6 by bolts and tightens the bolts by nuts so as to fix the first standard block pipe piece 12, the bottom standard block pipe piece 11 and the second bottom standard block pipe piece 13, installs a first adjacent block pipe piece 21 at the other end of the first standard block pipe piece 12, installs a second adjacent block pipe piece 22 at the other end of the second standard block pipe piece 13, and aligns the standard block transverse connecting holes 101 at the connecting position of the first standard block pipe piece 12 and the first adjacent block pipe piece 21 with the adjacent block transverse connecting holes 201, and aligns the standard block transverse connecting holes 101 at the connecting position of the second standard block pipe piece 13 and the second adjacent block pipe piece 22 with the adjacent block transverse connecting holes 201, the first standard block segment 12 and the first adjacent block segment 21, the second standard block segment 13 and the second adjacent block segment 22 can be fixed by tightening and fixing the two segments through bolts, finally, the capping block segment 3 is placed between the first adjacent block segment 21 and the second adjacent block segment 22, the capping block transverse connecting holes 31 on the left side and the right side of the capping block segment 3 are respectively aligned with the adjacent block transverse connecting holes 201 on the right side of the first adjacent block segment 21 and the left side of the second adjacent block segment 22 and then fixed by using bolts, so that the installation of one section of negative ring can be completed, the inserting grooves 4 on each segment of the other section of negative ring are aligned and inserted with the inserting blocks 5 of each segment on the first negative ring in a staggered installation mode with each segment of the first section of negative ring, the quick positioning of the segments can be facilitated, and the standard block longitudinal connecting holes 102 at the connecting part of the two sections of negative rings can be ensured, The longitudinal connecting holes 202 of the adjacent blocks and the longitudinal connecting holes 32 of the capping blocks are quickly aligned, and the longitudinal connecting holes 102 of the standard blocks, the longitudinal connecting holes 202 of the adjacent blocks and the longitudinal connecting holes 32 of the capping blocks at the connecting positions of the two sections of negative rings are fixedly connected by bolts.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing embodiments, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a shield constructs steel negative ring structure that starts which characterized in that: the sealing device comprises a bottom standard block pipe piece (11), wherein a first standard block pipe piece (12) and a second standard block pipe piece (13) are respectively installed on the left side and the right side of the bottom standard block pipe piece (11), a first abutting block pipe piece (21) and a second abutting block pipe piece (22) are respectively installed on the top of the first standard block pipe piece (12) and the top of the second standard block pipe piece (13), a capping block pipe piece (3) is installed between the first abutting block pipe piece (21) and the second abutting block pipe piece (22), capping block transverse connecting holes (31) are inwards formed in the left side and the right side of the capping block pipe piece (3), capping block longitudinal connecting holes (32) are inwards formed in the front side and the rear side of the capping block pipe piece (3), abutting block transverse connecting holes (201) are inwards formed in the left side and the right side of the first abutting block pipe piece (21) and the second abutting block pipe piece (22), the front and back sides of the first adjacent block pipe piece (21) and the second adjacent block pipe piece (22) are internally provided with adjacent block longitudinal connecting holes (202), the left and right sides of the bottom standard block pipe piece (11), the first standard block pipe piece (12) and the second standard block pipe piece (13) are internally provided with standard block transverse connecting holes (101), the front and back sides of the bottom standard block pipe piece (11), the first standard block pipe piece (12) and the second standard block pipe piece (13) are internally provided with standard block longitudinal connecting holes (102), the front walls of the bottom standard block pipe piece (11), the first standard block pipe piece (12), the second standard block pipe piece (13), the first adjacent block pipe piece (21), the second adjacent block pipe piece (22) and the top sealing block pipe piece (3) are internally provided with inserting grooves (4), and the front walls of the bottom standard block pipe piece (11), the first standard block pipe piece (12) and the top sealing block pipe piece (3) are internally provided with inserting grooves (4), The back wall of the second standard block pipe piece (13), the first adjacent block pipe piece (21), the second adjacent block pipe piece (22) and the capping block pipe piece (3) is integrally formed with an inserting block (5).

2. The shield starting steel negative ring structure of claim 1, wherein: the top sealing block transverse connecting holes (31), the adjoining block transverse connecting holes (201) and the standard block transverse connecting holes (101) are four in number, and the left side and the right side of each segment are respectively provided with two.

3. The shield starting steel negative ring structure of claim 1, wherein: two longitudinal connecting holes (32) of the top sealing block are arranged, and one longitudinal connecting hole is arranged on each of the front side and the rear side of the top sealing block pipe piece (3).

4. The shield starting steel negative ring structure of claim 1, wherein: the connecting structure is characterized in that six longitudinal connecting holes (202) of the adjacent blocks and six longitudinal connecting holes (102) of the standard blocks are arranged, and the front side and the rear side of the first standard block pipe piece (12) and the second standard block pipe piece (13) and the front side and the rear side of the first adjacent block pipe piece (21) and the second adjacent block pipe piece (22) are respectively provided with three longitudinal connecting holes.

5. The shield starting steel negative ring structure of claim 1, wherein: the cross section of the capping block pipe piece (3) is isosceles trapezoid.

6. The shield starting steel negative ring structure of claim 1, wherein: the cross-sectional shapes of the first adjoining block pipe piece (21) and the second adjoining block pipe piece (22) are right-angled trapezoids.

7. The shield starting steel negative ring structure of claim 1, wherein: the number of the inserting grooves (4) and the inserting blocks (5) on the bottom standard block pipe piece (11), the first standard block pipe piece (12), the second standard block pipe piece (13), the first adjacent block pipe piece (21), the second adjacent block pipe piece (22) and the capping block pipe piece (3) is the same as that of the standard block longitudinal connecting holes (102), the adjacent block longitudinal connecting holes (202) and the capping block longitudinal connecting holes (32) which are positioned on the same side of the bottom standard block pipe piece, the first standard block pipe piece (12) and the second standard block pipe piece, and the second standard block pipe piece and the capping block pipe piece (3) are positioned on.

8. The shield starting steel negative ring structure of claim 1, wherein: the standard block transverse connecting hole (101), the abutting block transverse connecting hole (201), the capping block transverse connecting hole (31), the standard block longitudinal connecting hole (102), the abutting block longitudinal connecting hole (202) and the capping block longitudinal connecting hole (32) are all communicated with a bolt through a groove (6), and the bolt is arranged on the inner side wall of the bottom standard block pipe piece (11), the first standard block pipe piece (12), the second standard block pipe piece (13), the first abutting block pipe piece (21), the second abutting block pipe piece (22) and the capping block pipe piece (3) through the groove (6).