JP5468988B2 - Seismic retrofit method for existing manholes - Google Patents

Description

  The present invention relates to a seismic improvement method for an existing manhole in which a sewer main is rigidly joined to a manhole side wall.

  In a conventional connection structure with a sewer pipe, the sewer pipe and the manhole side wall are rigidly joined (see Patent Document 1).

JP 2003-90077 A

The said patent document 1 has the following subject.
In the existing manhole where the sewer main is rigidly joined to the side wall of the manhole, when seismic motion is applied, the movement between the manhole and the sewer pipe will be different. If this difference in movement cannot be absorbed, the manhole and sewer pipe will be damaged.

At present, when a new sewerage facility (mainly manholes and sewerage pipes) is laid (new construction), it is generally connected via a flexible joint for earthquake resistance and water stoppage purposes.
However, the current situation is that flexible joints are not attached to manholes in previously installed sewerage facilities.
For this reason, in the Great Hanshin-Awaji Earthquake (occurred in January 1995), many damages were seen in the joint between the manhole and the sewer pipe, and the first sewer pipe from the manhole.

  When changing a conventional sewer pipe facility where the sewer pipe and manhole side wall are rigidly joined to an earthquake-resistant sewer pipe facility, the manhole and sewer pipe are once dug up from the ground and a flexible joint is attached. It is necessary to refill afterwards.

When a manhole or sewer pipe is dug up from the ground and a flexible joint is attached, the following problems arise.
Requires skill. Construction costs increase. It takes a work period. Causes traffic obstruction.

  An object of the present invention is to provide an existing manhole that can be easily made earthquake-resistant without digging up or backfilling an existing manhole or sewer pipe from the ground, where the sewer pipe and the manhole side wall are rigidly joined. The provision of earthquake resistance methods.

(About claim 1)
The existing manhole where the sewer main is rigidly connected to the side wall hole of the manhole side wall will be made earthquake resistant through the following process.
(Sewer main removal process)
In the existing manhole where the sewer main is rigidly joined to the side wall hole of the manhole, the pipe base of the sewer main of the rigid joint is removed leaving the vicinity of the outer wall to form a void.

(Spacer mounting process)
A spacer having a cylindrical portion whose cylindrical length is shorter than the length of the void and whose cylinder inner diameter is substantially equal to the inner diameter of the sewer main, and a plurality of fixtures for arranging the cylindrical portion coaxially with the sewer main is void. Attach to.

(Rehabilitation pipe making process)
A rehabilitation pipe having a pipe outer diameter equal to the inner diameter of the sewer main pipe and the inner diameter of the cylindrical section of the spacer is piped into the sewer main pipe through the cylindrical section of the spacer.
(Spacer removal process)
Unlock the fixture and remove the spacer from the void.

(Seismic joint installation process)
Install a seismic joint in the space around the base of the rehabilitation pipe.
(Filler filling process)
In order to ensure water tightness, the gap is filled by filling the inner wall of the vacant manhole with a filler.

(About claim 2)
The fixing tool for the spacer is a bolt nut and a camper.

(About claim 1)
In the sewer main pipe deletion process, the pipe base part of the sewer main pipe of the rigid joint portion is deleted leaving the vicinity of the outer wall.
For this reason, since the inside of a manhole does not connect with a natural ground, groundwater and earth and sand do not flow into a manhole. In addition, it does not hinder the flow of sewage from the sewer main to the manhole during construction.

  Even if the diameter of the sewer main is large, the portion near the outer wall remains, so the tube base portion of the rigid joint portion can be deleted with a simple tool.

In the existing manhole where the sewer main is rigidly joined to the side wall hole of the manhole side, the pipe base of the sewer main of the rigid joint part is deleted leaving the part near the outer wall, and a void is formed. A cylindrical portion having a cylindrical inner diameter equal to the inner diameter of the sewer main pipe and a spacer having a plurality of fixtures are attached.
For this reason, a rehabilitation pipe | tube can be accurately manufactured into a sewer main pipe | tube via the cylindrical part of a spacer.

After the rehabilitated pipe is manufactured, the seismic joint can be easily attached to the space around the base of the rehabilitated pipe by releasing the fixing of the fixture and removing the spacer from the space.
Since the seismic joint is installed in the space around the base of the rehabilitation pipe, the existing manhole can be made earthquake resistant.

(About claim 2)
The cylindrical portion of the spacer is divided into a plurality. For this reason, it becomes easy to remove the spacer from the void in the spacer removing step.
(Claim 3)
Bolt nuts and campers that are readily available can be used for the spacer fixture.

(A) is explanatory drawing which shows the sewer main removal process of the seismicization method of the existing manhole which concerns on Example 1 of this invention, (b) is the seismicization method of the existing manhole which concerns on Example 1 of this invention It is explanatory drawing which shows a spacer attachment process. It is explanatory drawing which shows the renovated pipe pipe manufacturing process of the earthquake resistance method of the existing manhole which concerns on Example 1 of this invention. (A), (b) is explanatory drawing which shows the earthquake-resistant joint attachment process of the earthquake-proofing method of the existing manhole which concerns on Example 1 of this invention, (c) is the earthquake resistance of the existing manhole which concerns on Example 1 of this invention It is explanatory drawing which shows the filler filling process of the conversion method. (A) is explanatory drawing which shows the other example of a fixing tool, (b) is explanatory drawing which shows the example which attached the positioning plate. It is explanatory drawing which shows the malfunction which arises when not using a spacer. (A) is explanatory drawing which shows the spacer removal process of the seismicizing method of the existing manhole which concerns on the modification of this invention, (b) is the seismic joint attachment process of the seismicizing method of the existing manhole which concerns on the modification of this invention (C) is explanatory drawing which shows the filler filling process of the earthquake resistance method of the existing manhole which concerns on the modification of this invention. It is explanatory drawing which shows the modification of a spacer.

The existing manhole where the sewer main is rigidly joined to the manhole side wall will be made earthquake resistant through the following process.
Delete the base of the sewer main of the existing manhole where the sewer main is rigidly connected to the side wall hole of the manhole, leaving a portion near the outer wall, forming a void (sewer main deletion process) ).

  A spacer having a cylindrical portion whose cylindrical length is shorter than the length of the gap and whose cylindrical inner diameter is equal to the inner diameter of the sewer main, and a plurality of fixtures for arranging the cylindrical portion coaxially with the sewer main is attached to the space ( Spacer mounting process).

  A rehabilitation pipe having a pipe outer diameter substantially equal to the inner diameter of the sewer main pipe and the cylindrical part of the spacer is piped into the sewer main pipe through the cylindrical part of the spacer (rehabilitation pipe making process).

Release the fixture and remove the spacer from the void (spacer removal process).
Install an earthquake-resistant joint in the space around the base of the rehabilitated pipe (earthquake-resistant joint installation process).
Fill the empty manhole inner wall with a filler to close the gap (filler filling process).

  This method of making an existing manhole earthquake-proof can be easily made earthquake-resistant without digging up or refilling manholes or sewer pipes.

[Example 1]
A method of making an existing manhole earthquake-proof according to Embodiment 1 (corresponding to claims 1 and 3) of the present invention will be described with reference to FIGS.
The existing manhole (made of concrete) buried in the soil is formed by rigidly joining the sewer main pipe 2 (fume pipe) to the side wall hole 13 of the manhole side wall 12 erected from the edge of the bottom slab 11. After that, it is renovated to earthquake-proof manhole A.

  The earthquake-resistant manhole A, which has been refurbished using the seismic method for existing manholes, has a manhole body 1, a sewer main 2 in which the pipe base of the rigid joint portion has been removed leaving the vicinity of the outer wall, and the sewer main 2 The rehabilitation pipe 3 is formed in a hollow space 14 and the earthquake-resistant joint 4 is disposed in the space 14 and the gap is closed with a manhole filler m {see FIG. 3 (c)}.

(Sewer main removal process)
Using a machine or a tool, delete the pipe base of the sewer main 2 of the existing manhole where the sewer main 2 is rigidly joined to the side wall hole 13 of the manhole side wall 12 leaving the vicinity of the outer wall, A void 14 is formed {see FIG. 1 (a)}.

(Spacer mounting process)
A cylindrical part 51 whose cylindrical length is shorter than the length of the void 14 and whose cylindrical inner diameter d is equal to the inner diameter D of the sewer main pipe 2, and four fixtures for arranging the cylindrical part 51 coaxially with the sewer main pipe 2. The spacer 5 having 52 is attached to the space 14 {see FIG. 1 (b)}.

In the present embodiment, the fixture 52 is a nut 53 fixed to four locations of the cylindrical portion 51 and a bolt 54 that is screwed into the nut 53.
Specifically, the head portion of the bolt 54 is rotated with a wrench or the like, and the spacer 5 is positioned so that the cylindrical portion 51 is coaxial with the sewer main pipe 2.

(Rehabilitation pipe making process)
With the spacer 5 attached to the empty space 14, the rehabilitation pipe 3 having a pipe outer diameter equal to the inner diameter D of the sewer main pipe 2 and the cylindrical inner diameter d of the spacer 5 is piped into the sewer main pipe 2 through the inside of the cylindrical portion 51. (See FIG. 2).
If the spacer 5 is not used, as shown in FIG. 5, the rehabilitation pipe 3 spreads and the seismic joint 4 cannot be attached to the space 14.

(Spacer removal process)
The head of the bolt 54 is loosened by turning it with a wrench or the like, the cylindrical portion 51 is removed from the rehabilitation pipe 3, and the spacer 5 is removed from the space 14.

(Seismic joint installation process)
From the manhole body 1, the seismic joint 4 is pushed in and attached to the space 14 on the outer periphery of the base of the rehabilitated pipe 3 {see (a, b) in FIG. 3}.

The earthquake-resistant joint 4 includes a long-diameter small cylindrical portion 41 whose inner circumference is substantially equal to the outer circumference of the rehabilitated pipe 3, a short-diameter large cylindrical portion 42 whose outer circumference is substantially equal to the inner wall of the cavity 14, and a connecting portion 43 that connects the two. A joint main body 40 (made of rubber), a steel cylinder 44 fitted into the short diameter large cylindrical portion 42, a steel ring 45 fitted around the long diameter small cylindrical portion 41, and a short diameter large cylindrical portion. And a stainless steel band 36 attached to the outer periphery of 42.
The earthquake-resistant joint is not limited to the earthquake-resistant joint 4 and may have a structure other than this.

(Filler filling process)
The manhole filler m is filled into the manhole inner wall side of the space 14 where the seismic joint 4 is fitted to close the gap {see (c) of FIG. 3}.

The seismicizing method for an existing manhole in Example 1 has the following advantages.
Method of removing the pipe base of the sewer main 2 of the existing manhole where the sewer main 2 is rigidly joined to the side wall hole 13 of the manhole side wall 12 using a machine or a tool, leaving the portion near the outer wall. Therefore, a large cutting machine is not required.
In addition, since the manhole does not communicate with the natural ground, groundwater and earth and sand from the natural ground do not flow into the manhole during the earthquake resistance construction. Furthermore, it does not hinder the flow of sewage from the sewer main 2 into the manhole.
Even if the diameter of the sewer main 2 is large, the pipe base portion of the sewer main 2 can be removed with a simple tool while leaving the vicinity of the outer wall.

The existing manhole where the sewer main pipe 2 is rigidly joined to the side wall hole 13 of the manhole side wall 12 is removed by removing the pipe base portion of the sewer main pipe 2 of the rigid joint portion leaving the vicinity of the outer wall, and forming a void 14. A spacer 5 having a cylindrical portion 51 and four fixing members 52 having a cylindrical inner diameter d equal to the inner diameter D of the sewer main pipe 2 is attached to the space 14.
For this reason, the rehabilitation pipe 3 can be accurately manufactured into the sewer main pipe 2 through the cylindrical portion 51 of the spacer 5.

  If the bolt 54 is loosened and the spacer 5 is removed from the void 14 after the rehabilitated tube 3 is manufactured, the earthquake-resistant joint 3 can be easily fitted and attached to the void 14 on the outer periphery of the base of the rehabilitated tube 3. In addition, since the fixture of the spacer 5 is the volt | bolt 54 and the nut 53, it can obtain easily and is cheap.

  Since the seismic joint 3 is fitted and attached to the space 14 on the outer periphery of the base portion of the rehabilitation pipe 3, the existing manhole can be made earthquake resistant. There is no need to dig up manholes or sewer pipes from the ground or refill them.

(Modification)
a. The spacer 5 may be composed of the cylindrical portion 51 and the camper 55. In the spacer mounting step, the camper 55 is press-fitted from the manhole body 1 into the void 14 on the outer periphery of the base portion of the cylindrical portion 51 (see FIG. 4A).
The cylindrical portion 51 may be omitted, the camper 55 may be used as a ring to form the spacer 5, and the handle 56 may be pulled out after the pipe production (see FIG. 7).
Further, the spacer 5 may be a split type such as a half crack.

b. When the spacer 5 is attached to the space 14 in the spacer attaching step, the positioning plate 6 (thin plate) may be provided at a plurality of positions across the inner wall of the cylindrical portion 51 and the inner wall of the base of the sewer main pipe 2. {See (b) of FIG. 4}.
With this configuration, the inner wall of the cylindrical part 51 of the spacer 5 and the inner wall of the base part of the sewer main pipe 2 are connected by the positioning plate 6, so that the spacer 5 can be easily arranged coaxially with the sewer main pipe 2. The rehabilitated pipe 3 can be made into the sewer main pipe 2 more easily.

c. The earthquake-resistant joint 4 includes a long-diameter small cylindrical portion 41 whose inner circumference is substantially equal to the outer circumference of the rehabilitated pipe 3, a short-diameter large cylindrical portion 42 whose outer circumference is substantially equal to the inner wall of the cavity 14, and a connecting portion 43 that connects the two. A joint body 40 (made of rubber), a steel cylinder 44 fitted into the short diameter large cylindrical portion 42, and a stainless steel band attached to the outer periphery of the long diameter small cylindrical portion 41 and the outer periphery of the short diameter large cylindrical portion 42. 35 and 36 may be used (see FIG. 6).

  If this seismicization method for existing manholes is adopted, a conventional existing manhole in which a sewer pipe is rigidly joined to the side wall hole of the manhole side wall can be changed to an earthquake-proof manhole without digging up the ground.

A Seismic-proof manhole m Manhole filler 1 Manhole body 2 Sewer main 4 Seismic joint 12 Manhole side wall

Claims (3)

A sewer main deletion process in which the base part of the sewer main of the existing manhole, where the sewer main is rigidly joined to the side wall hole of the manhole side wall, is deleted leaving the vicinity of the outer wall, forming a void. ,
A cylindrical portion having a cylindrical length shorter than the length of the void and having a cylindrical inner diameter equal to the inner diameter of the sewer main, and a spacer having a plurality of fixtures for arranging the cylindrical portion coaxially with the sewer main A spacer mounting process for mounting in a void;
A rehabilitating pipe producing step for producing a renovated pipe having a pipe outer diameter substantially equal to the inner diameter of the sewer main pipe and the cylindrical part of the spacer into the sewer main pipe through the cylindrical section;
A spacer removal step of releasing the fixation of the fixture and removing the spacer from the void;
An earthquake-resistant joint mounting step for attaching an earthquake-resistant joint to the void in the outer periphery of the base of the rehabilitated pipe;
A method for seismicizing an existing manhole, comprising a filling material filling step of filling the inner wall side of the empty manhole with a filling material to close a gap.   The method of claim 1, wherein the cylindrical portion of the spacer is divided into a plurality of parts.   The method for making an existing manhole earthquake resistant according to claim 1 or 2, wherein the fixture of the spacer is a bolt nut or a camper.

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