JP2818807B2 - Construction method of duct extension in manhole - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a duct extension opening in a manhole, and more particularly to a method of fixing an extension duct sleeve to a through hole for providing an extension hole. .

[Conventional technology]

Conventionally, on a side wall of an existing underground structure such as a manhole, a place for providing a duct extension port is prepared in advance, a through hole is opened at the time of extension, and piping for inserting a communication cable or the like into the through hole is performed. Construction methods are known. A resin layer is attached to the outer periphery of an additional duct sleeve having a flange portion having a diameter slightly larger than the diameter of the through hole at one end of the through hole for providing the duct addition port, and the resin attachment surface The present applicant has proposed a construction method in which a threaded surface is formed on a threaded surface, and a tightening ring is screwed and fixed to the threaded surface.

[Problems to be solved by the invention]

By the way, in the existing duct opening in the existing manhole, `` protective concrete '' is cast outside to protect the duct opening, its thickness is not constant, and in the case of the above-mentioned conventional construction method, The length of the duct sleeve may be insufficient, so that the socket (tightening ring) cannot be screwed from the outside, and the adhesive filled between the outer surface of the duct sleeve and the opposing surface of the through-hole will not be removed. Before curing, it is not possible to insert or connect a conduit for inserting a communication cable or the like. If the conduit is forcibly inserted and connected, there is a problem that the duct sleeve may fall out of the side wall of the manhole. Therefore, it is necessary to wait for the next work until the adhesive is cured, and there is a problem that the work time is long.

The present invention has been made to solve the above problems.

[Means for solving the problem]

In order to achieve this object, the present invention provides a through hole at a predetermined portion of an underground structure such as an existing manhole, and a duct expansion opening which is used to perform a pipe for inserting a communication cable or the like into the through hole. An O-ring, an adhesive accommodating groove, and a longitudinal direction of the sleeve are provided on an outer peripheral portion of the extension duct sleeve which is fitted into the through hole from the inside to the outside of the manhole and is fixed to the manhole. And a plurality of elastic support pieces and the like disposed along the holes are inserted into and fixed to the through holes.

[Action]

According to the above-mentioned method, the additional duct sleeve is stably and firmly supported by the elastic support piece when inserted into the through-hole, and a duct for inserting a communication cable or the like is immediately inserted and connected to the duct sleeve. The installation of the duct sleeve can be followed by the installation work of the pipeline and the insertion work of the communication cable, etc., and the construction time can be shortened.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 5, reference numeral 1 denotes an existing manhole provided underground, and a number of existing pipelines 2 for laying a communication cable or the like are laid between the manholes 1 and 1.
The pipeline 2 is provided in a plurality of stages vertically and a plurality of rows in the horizontal direction. In addition to the existing pipeline 2, the manhole 1 is expected to be expanded in the future. A space 3 to be added is provided above the pipe 2.

When a duct expansion port is provided at the position of the space 3 to be expanded, a through hole 4 of a predetermined size is formed with an appropriate drilling tool.
(See FIG. 4). The additional duct sleeve 5 shown in FIGS. 1 to 3 is fitted into the through hole 4. The duct sleeve 5 is made of, for example, vinyl chloride. One end of the duct sleeve 5 is inserted into the through hole 4, and the joint 6 is formed on the other end. On the side of the additional duct sleeve 5 inserted into the through hole 4, a resin layer 7 is coated on the outer periphery of the length of the through hole 4, that is, the length substantially corresponding to the thickness of the side wall 1 a of the manhole 1. Is being worn. The resin layer 7 has an outer diameter substantially equal to the inner diameter of the through hole 4,
On its outer circumference, O-rings 8, 8 are provided at two locations in the length direction.
An adhesive accommodating groove 9 for accommodating an adhesive made of an impregnated body is formed, and three iron rubbers 10 made of urethane-based resin are arranged in a portion near the joint portion 6 along the length direction of the sleeve at a constant interval. It is arranged in. This iron rubber
Reference numeral 10 projects outward from the surface of the resin layer 7 as shown in FIG. 1, and its height, length, width, number, etc. may be changed as appropriate.

The application of the resin layer 7 to the duct sleeve 5 is performed in advance, and the mounting of the O-ring 8, the storage of the impregnated adhesive in the adhesive storage groove 9, the selection of the iron rubber 10, and the like may be performed at a construction site. . In the above embodiment, the diameter of the through hole 4 is 128.5 mm, the maximum diameter of the duct sleeve 5 is 124 mm, the outer diameter of the resin layer 8 is 125.5 mm, and the outer diameter of the iron rubber 10 is 130.5 mm.
Met. In addition, the length of the duct sleeve 5 is set to be longer than the thickness even when the protective concrete is cast.

In the above embodiment, the resin layer 7 is omitted, and the O-rings 8, 8 and the adhesive accommodating groove 9,
Iron rubber 10 or the like may be provided in diameter.

In the construction described above, when constructing the duct addition opening, first, a through hole 4 is opened in the space 3 where the manhole 1 is to be added, and the resin layer 7 is formed in the duct sleeve 5 as shown in FIGS. O-ring 8, 8
Is inserted, the impregnated adhesive is accommodated in the adhesive accommodating groove 9, and the iron rubber 10 is provided. Then, the iron rubber 10 is inserted into the through hole 4 with the joint portion 6 facing forward. The end is hit by, for example, to insert the manhole 1 to the wall surface. In this state, the duct sleeve 5
The iron rubber 10 elastically deforms, and the duct sleeve 5 is uniformly supported in the circumferential direction with respect to the through hole 4 so that the duct sleeve 5 is stably formed. And it is strongly supported. The impregnated adhesive cures with the passage of time and bonds the duct sleeve 5 and the through hole 4.

Therefore, as shown in FIG. 4, the duct 2 such as a steel pipe or a vinyl chloride pipe is connected to the joint 6 of the duct sleeve 5 in a state where the duct sleeve 5 is inserted into the through-hole 4, and after the pipe is laid. The work of inserting a communication cable or the like into the conduit 2 can be performed continuously. Further, when the impregnating adhesive cures, the connection between the duct sleeve 5 and the through hole 4 becomes stronger, and since the O-rings 8, 8 are adhered, the duct sleeve 5 extends from the expanded portion into the manhole 1. Water leakage is reliably prevented.

〔The invention's effect〕

As described above in detail, according to the method of constructing the duct addition opening in the manhole of the present invention, the following effects can be obtained.

. Just insert the additional duct sleeve into the through hole,
The duct sleeve is stably and firmly supported in the through-hole by the elastic support piece, so that the work of connecting the pipeline can be performed immediately and the construction time can be reduced. Moreover, the duct sleeve can be securely mounted without being affected by the thickness of the manhole wall, the presence or absence of protective concrete, the thickness thereof, and the like.

. Since the end of the duct sleeve does not protrude into the manhole, it does not hinder the installation of the jig during the subsequent work, for example, the work of pulling out the communication cable.

. The structure can be simpler than the conventional duct sleeve, and the price can be reduced.

[Brief description of the drawings]

1 is a side sectional view of an additional duct sleeve of the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, FIG. 3 is an enlarged sectional view of a portion A in FIG. 1, and FIG. FIG. 5 is a side sectional view showing a state in which the additional duct sleeve of the present invention is inserted into a through hole formed in a manhole, and FIG. 5 is a schematic side view showing a piping state of an existing manhole. DESCRIPTION OF SYMBOLS 1 ... Manhole, 2 ... Pipe line, 3 ... Space to be added, 4 ... Through-hole, 5 ... Duct sleeve, 6 ... Joint part, 7 ... Resin layer, 8 ... O-ring, 9 ... … Adhesive accommodating groove, 10… iron rubber.

Continued on the front page (72) Inventor Tsuneo Tsuneo 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Takashi Sakuma 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone (56) References JP-A-63-48115 (JP, A) JP-A-1-105821 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02G 9/00 -9/12

Claims (1)

(57) [Claims] A through hole is provided at a predetermined portion of an existing underground structure such as a manhole, and a duct extension port through which a communication cable or the like is inserted through the through hole is provided. An O-ring, an adhesive accommodating groove, and a lengthwise direction of the sleeve are provided on an outer peripheral portion of the extension duct sleeve, which is inserted from the inside to the outside and fixed to the manhole, facing the inner peripheral surface of the through hole. A method for constructing a duct extension opening in a manhole, wherein a plurality of elastic support pieces are provided and fitted and fixed in through holes.