Manhole structure constructing method, manhole structure water-stop flexible joint and manhole structure

Abstract

A method is disclosed for constructing a manhole structure in which a manhole and a pipe are joined together by using a waterproof flexible joint. The joint includes a rigid cylindrical portion and a cylindrical flexible portion that has a covering portion to be fixed around an outer periphery of said pipe, a fixing portion fixed to an outer periphery of said rigid cylindrical portion and to be fixed to the manhole and a connecting portion connecting the covering portion to the fixing portion and made of an elastic material being capable of absorbing a displacement between the manhole and the pipe. The waterproof flexible joint is located around the outer periphery of the pipe, and the covering portion is fixed around the outer periphery of the pipe. Then, a filler for the manhole is poured around an outer periphery of the fixing portion.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a method for constructing manhole structures, waterproof flexible joints for such manhole structures and the manhole structures thus constructed.

[0003] 2. Related Art Statement

[0004] There are a digging/reburying construction method, a jacking construction method, etc. as pipe-paving technique. According to the jacking construction method, a starting vertical hole and an arrival vertical hole are first dug, and then a sewer pipe is pushed into horizontally from the start vertical hole by means of a jack, while a horizontal hole is being dug by a horizontal boring machine.

[0005] FIG. 4 is a vertical sectional view of a part of a conventional manhole structure 41. As shown in FIG. 4, a manhole 42 is placed in a vertical hole. In order to minimize working, a steep pipe is generally used as an earth-retaining wall when such a vertical hole is dug. In the construction of the manhole, a steel casing pipe serves as an outer mold frame 44, and the manhole 42 is formed between the outer mold frame 44 and an inner mold frame 45.

[0006] When the manhole 42 is constructed within such a vertical hole, an end portion of a pipe 43 such as sewer pipe, as previously placed, is buried in a concrete wall 46 of the manhole as required from an installation space for the manhole 42.

[0007] Further, as shown in FIG. 4, an interface 47 between the pipe 43 and the concrete wall 46 of the manhole is likely to serve as a passage for leaking water. Under these circumstances, a sand-attached short pipe in which sand 48 is glued around an outer peripheral surface 43a of the pipe 43 is often used.

[0008] In the manhole structure 41 shown in FIG. 4, the concrete 46 is rigidly joined to the pipe 43, so that there is the possibility that the pipe 43 may be broken on earthquake or the like. Particularly when the pipe 43 is a Hume pipe or porcelain pipe, it is likely to be broken on ground displacement.

[0009] When the pipe 3 is a flexible pipe such as a resin pipe, it is less likely to be broken by ground displacement, but there is still a high possibility that it may be broken. Further, the resin pipe is not bonded to the concrete, so that a water passage is formed when a sand-attached short pipe is not used. Thus, the resin pipe has a problem in waterproof.

[0010] As shown in FIG. 4, in the case of the sand-attached short pipe, a fine gap 49 or the like is formed under the pipe 43 due to the dewatering sink before curing of the concrete 43 or after drying shrinkage of the concrete 46 with lapse of years, thereby causing water leakage.

[0011] Since the flexible pipe such as the resin pipe is particularly flexible, it is likely to become flat due to ground pressure or the like, so that formation of water passage cannot be completely prevented even by using the sand-attached short pipe.

SUMMARY OF THE INVENTION

[0012] It is an object of the present invention to form a soft connection of the manhole structure through joining the manhole to the pipe with the water-proof flexible joint, so that the pipe can be prevented from being broken on earthquake or the like.

[0013] Further, it is another object of the present invention to completely prevent water leakage between the manhole and the pipe.

[0014] The present invention relates to a method for constructing a manhole structure in which a manhole and a pipe are joined together, said method comprising: preparing a waterproof flexible joint for the manhole structure, said waterproof flexible joint comprising a rigid cylindrical portion and a cylindrical flexible portion, said cylindrical flexible portion comprising a covering portion to be fixed around an outer periphery of said pipe, a fixing portion to be fixed to said manhole and a connecting portion connecting the covering portion to the fixing portion, said fixing portion being fixed to an outer periphery of said rigid cylindrical portion, said connecting portion being made of an elastic material being capable of absorbing a displacement between the manhole and the pipe; locating the waterproof flexible joint around the outer periphery of the pipe; fixing the covering portion around the outer periphery of the pipe; and pouring a filler for the manhole around an outer periphery of the fixing portion.

[0015] Further, the present invention relates to a waterproof flexible joint for the manhole structure to be used in the above construction method as well as to the manhole structure obtained by the above method.

[0016] The present invention is based on the knowledge that the manhole structure in which the joint portion between the pipe in the jacking method and the concrete manhole cast on site is made as a soft connection can be obtained by using the specific waterproof flexible joint for the manhole structure.

[0017] According to the present invention, the manhole structure, which comprises the manhole, the pipe and the waterproof flexible joint for the manhole structure, is constructed by fixing the waterproof flexible joint around the outer periphery of the pipe and then pouring the manhole filler around the joint.

[0018] The waterproof flexible joint according to the present invention comprises the rigid cylindrical portion and the cylindrical flexible portion. The rigid cylindrical portion is located on a radially outer side of the cylindrical flexible portion and serves to fix the cylindrical flexible portion to the manhole.

[0019] The cylindrical flexible portion comprises the covering portion to be fixed around the outer periphery of the pipe, the fixing portion to be fixed to the manhole, and a connecting portion connecting the covering portion to the fixing portion.

[0020] According to the present invention, the fixing portion of the cylindrical flexible portion is fixed to the outer periphery of the rigid cylindrical portion. The rigid cylindrical portion serves to fix the fixing portion of the cylindrical flexible portion to the manhole.

[0021] According to the present invention, the manhole structure can be constructed by fixing the covering of the cylindrical flexible portion to the outer periphery of the pipe and pouring the manhole filler around the outer periphery of the fixing portion of the cylindrical flexible portion.

[0022] In the present invention, the filler for manhole (hereinafter referred to as “manhole filler”) includes concrete to be poured into a mold frame for constructing the wall of the manhole on site or a filler to be filled in a space between an inner face of a hole formed in the wall of an assembled manhole or the like and the waterproof flexible joint for fixing the waterproof flexible joint to the face of the hole.

[0023] In the present invention, the connecting portion of the cylindrical flexible portion is made of the elastic material capable of absorbing displacement between the manhole and the pipe. This connecting portion is located between the manhole and the pipe, and serves to absorb the displacement between the manhole and the pipe.

[0024] In the present invention, the rigid cylindrical portion supports the fixing portion of the cylindrical flexible portion and fix the fixing portion to the manhole when the manhole filler is poured around the outer periphery of the fixing portion of the cylindrical flexible portion.

[0025] In the present invention, the rigid cylindrical portion keeps a space between the fixing portion and the covering portion of the cylindrical flexible portion, and the connecting portion of the cylindrical flexible portion absorbs displacement between the manhole and the pipe within this space.

[0026] According to the present invention, after the waterproof flexible joint for manhole structure is fixed around the outer periphery of the pipe, the manhole filler is poured around the outer periphery of the waterproof flexible joint. Thus, the manhole structure having the manhole and the pipe joined together by the soft connection can be extremely effectively constructed.

[0027] These and other objects, features and effects of the invention will be apparent upon reading the following description of the invention in conjunction with the attached drawings, with the understanding that any modifications, variations and changes can be made to the invention by the skilled person in the art to which the invention pertains.

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] For a better understanding of the invention, reference is made to the attached drawings, wherein:

[0029] FIG. 1 is a vertical sectional view of a part of one embodiment of the manhole structure according to the present invention;

[0030] FIG. 2 is a perspective view of a waterproof flexible joint for the manhole structure according to the present invention;

[0031] FIG. 3 is a vertical sectional view of a part of another embodiment of the manhole structure according to the present invention; and

[0032] FIG. 4 is a vertical sectional view of a part of a conventional manhole structure.

DETAILED DESCRIPTION OF THE INVENTION

[0033] The present invention will be explained below in more detail.

[0034] (1) Manhole

[0035] In the present invention, manholes made of concrete cast on site as well as other manholes produced preliminarily in factories, such as make-up assembling manholes, can be used as manholes.

[0036] In the case of the make-up assembling manhole, a hole for the connection with the pipe may be formed in the wall of the manhole on site, but the hole is preferably formed in a factory or the like having well controlled quality management.

[0037] In the present invention, the manhole made of the concrete cast on site can be formed by pouring the manhole filler in a mold frame on site of the vertical hole.

[0038] (2) Pipe

[0039] In the present invention, the pipe is a pipe for connecting one manhole to another manhole or the like. Typically, the pipe is a sewer pipe. Such pipes can be placed between at least two vertical holes by the jacking method.

[0040] (3) Manhole Filler

[0041] In the present invention, the manhole filler is used to construct the manhole on site or fixing the waterproof flexible joint to the inner face of the hole of the make-up assembled manhole.

[0042] As such a manhole filler, concrete, mortar concrete or the like can be used at various quality levels without particular limitations. If the space is narrow between the outer periphery of the rigid cylindrical body and the inner face of the hole of the manhole, particularly non-shrinkable mortar, resin mortar, epoxy resin or the like may be favorably used.

[0043] In the present invention, after the pipes are laid between at least two vertical holes by the jacking method, the manhole is constructed by assembling make-up concrete members inside the vertical hole and the manhole structure is constructed by fixing the waterproof flexible joint to the inner face of the cut hole of the assembled manhole with the manhole filler after fixing the joint around an end portion of the pipe.

[0044] (4) Waterproof Flexible Joint for Manhole Structure

[0045] In the present invention, the waterproof flexible joint for manhole structure comprises the rigid cylindrical portion and the cylindrical flexible portion.

[0046] In the present invention, in the case of the manhole to be constructed on site, the waterproof flexible joint can be attached to an end portion of the pipe placed by the jacking method or the like before forming the manhole wall of the concrete manhole.

[0047] Further, according to the present invention, in the case of the assembled make-up concrete manhole, after the manhole wall is formed, the waterproof flexible joint can be attached to the pipe placed by the jacking method. In this case, after another pipe is additionally joined to an end of the pipe placed by the jacking method such that an end of another pipe may extend inside the manhole through the hole, the waterproof flexible joint can be inserted between the hole of the manhole wall and another pipe.

[0048] (5) Cylindrical Flexible Portion

[0049] In the present invention, the cylindrical flexible portion is fixed to the outer periphery of an end of the pipe, and comprises the covering portion to cover that end of the outer periphery of the pipe, the fixing portion to be fixed to the manhole, and the connecting portion to connect the covering portion to the fixing portion.

[0050] The fixing portion of the cylindrical flexible portion is fixed to the rigid cylindrical portion. The fixing portion can be fixed to the rigid cylindrical portion by any of various fixing means without particular limitations. As the fixing means, bonding or the like may be used. If durability or stability is considered, particularly a fastening band or a tightening band may be favorably used.

[0051] The covering portion of the cylindrical flexible portion covers and is fixed to the outer periphery of an end of the pipe. The covering portion may be fixed to that end of the outer peripheral portion of the pipe by any of various fixing means. Particularly a tightening band can be favorably used.

[0052] As the connecting portion of the cylindrical flexible portion, various members may be used without limitation on their shape, etc. so long as the members are made of elastic materials capable of absorbing displacement between the manhole and the pipe within a space formed between the rigid cylindrical portion and the pipe.

[0053] In the present invention, the manhole is formed by pouring the manhole filler around the outer periphery of the fixing portion of the cylindrical flexible portion attached around the pipe.

[0054] In the present invention, the space between the inner face of the hole of the preliminarily formed manhole and the rigid cylindrical portion can be buried by pouring the manhole filler around the outer periphery of the fixing portion of the cylindrical flexible portion attached around the pipe.

[0055] In the present invention, the fixing portion and the covering portion of the cylindrical flexible portion are fixed to the manhole and the pipe, respectively. By doing so, the constant space can be kept between the manhole and the pipe. Further, even if the manhole and the pipe exhibit different displacements to form a positional deviation, the cylindrical flexible portion can effectively absorb such displacements to prevent the joining portion from being broken.

[0056] In the present invention, the cylindrical flexible portion can be formed from an elastic material. Any elastic material does without particular limitations so long as it is soft enough to absorb displacement between the manhole and the pipe. Cylindrical flexible portions made of various materials such as rubber may be used.

[0057] The cylindrical flexible portion may have a structure having double cylindrical portions folded back midway. The double cylindrical portions of the cylindrical flexible portion serve as a covering portion and a fixing portion, respectively. The double cylindrical portions is connected together by a connecting portion.

[0058] The cylindrical flexible portion may be provided with the rigid cylindrical portion at an inner side of the outer cylindrical portion so that the outer cylindrical portion may not be folded inside.

[0059] (6) Rigid Cylindrical Portion

[0060] In the present invention, the rigid cylindrical portion can be made of any of various materials in any of various forms without particular limitations. In the present invention, a rigid pipe may be used. As such a pipe, a corrosion-resistant pipe made of stainless steel or the like may be favorably used.

[0061] The rigid cylindrical portion ensures the space to receive the connecting portion of the cylindrical flexible portion between the rigid cylindrical portion and the pipe. For this purpose, the rigid cylindrical portion preferably has strength that makes it difficult to be deformed with pressure of cast concrete, etc. In the present invention, the rigid cylindrical portion made of the same material as that of the pipe may be used.

[0062] (7) Protective Member

[0063] In the present invention, a protective member may be used to prevent unfavorable flow-in of the manhole filler or to assuredly form the space to receive the connecting portion of the cylindrical flexible portion.

[0064] Such a protective member keeps a specific space between the rigid cylindrical portion and the pipe, between the rigid cylindrical portion and the covering portion of the cylindrical flexible portion or between the manhole and the pipe.

[0065] Thus, the protective member may be provided between the rigid cylindrical portion and the covering portion of the cylindrical flexible portion or between the inner mold frame to receive the manhole filler and the connecting portion of the cylindrical flexible portion, for example.

[0066] In the present invention, the protective member may be removed after the manhole filler is poured and the manhole is formed.

[0067] (8) Jaw Portion

[0068] In the present invention, a jaw portion may be provided at the outer periphery of the fixing portion of the cylindrical flexible portion. Such a jaw portion bites into the manhole filler so that it may fix the fixing portion of the manhole. Further, the jaw portion serves to enhance adhesion between the fixing portion and the manhole filler.

[0069] Any material and any shape may be employed for the jaw portion so long as it bites into the manhole filler and is fixed inside the manhole filler. The jaw portion is preferably made difficult to be deformed by the pressure of the cast manhole filler.

[0070] In the present invention, an adhesive or a pressure-sensitive adhesive to bond the jaw portion to the manhole filler may be applied to that surface of the jaw portion which contacts the manhole filler.

[0071] As the adhesive, a water-swelling rubbery adhesive, a non-vulcanizing butyl rubber-based adhesive or a water-swelling sealant may be used. The non-vulcanizing butyl rubber-based adhesive is preferred.

[0072] In the case of the waterproof flexible joint having the fixing portion with the jaw portion and the adhesive attached to the outer surface thereof, when the jaw portion to which the adhesive is applied at the outer periphery of the fixing portion is buried in the manhole filler, water permeation between the manhole and the rigid cylindrical portion can be prevented, and water leakage through the interface of the manhole filler can be completely prevented.

[0073] The present invention will be explained in more detail with reference to the attached drawings.

[0074] FIG. 1 is a vertical sectional view of a part of one embodiment of the manhole structure according to the present invention. FIG. 2 is a perspective view of a waterproof flexible joint for the manhole structure according to the present invention. FIG. 3 is a vertical sectional view of a part of another embodiment of the manhole structure according to the present invention.

[0075] As shown in FIGS. 1 and 2, the manhole structure 1 has a manhole 2, a pipe 3 and a waterproof flexible joint 4 for the manhole structure.

[0076] In the present invention, the manhole structure 1 is constructed by fixing the waterproof flexible joint 4 around the outer periphery of the pipe 3 and then pouring the manhole filler around the outer periphery of the waterproof flexible joint 4.

[0077] The manhole structure 1 is provided with the waterproof flexible joint around the outer periphery of the pipe 3. The waterproof flexible joint 4 comprises a rigid cylindrical portion 5 and a cylindrical flexible portion 6.

[0078] The cylindrical flexible portion 6 comprises a covering portion 6a to cover the outer periphery of the pipe 3, a fixing portion 6b to be fixed to the manhole 2 and a connecting portion 6c connecting the covering portion 6a to the fixing portion 6b.

[0079] The fixing portion 6b is fixed to the outer periphery of the rigid cylindrical portion 5. The connecting portion 6c is made of an elastic material capable of absorbing displacement between the manhole 2 and the pipe 3.

[0080] The covering portion 6a is fixed around the outer periphery of the pipe 3. The manhole 2 is formed by pouring the manhole filler around the outer periphery of the fixing portion 6b.

[0081] In the present invention, the fixing portion 6b may be provided with a jaw portion 7 as shown in FIGS. 1 and 2. The jaw portion 7 has a non-vulcanizing butyl rubber layer 8 at its surface. The jaw portion 7 bites into the manhole 2.

[0082] In the present invention, the covering portion 6a can be fixed to the outer periphery of the pipe 3 by using a pipe-tightening band 9 as shown in FIGS. 1 and 2. The fixing portion 6b can be fixed to the rigid cylindrical portion 5 by using a rigid cylindrical portion-tightening band 10.

[0083] The manhole structure 1 of FIG. 1 is constructed in a vertical hole, and an earth-retaining casing 11 may be used as a mold frame for the manhole filler.

[0084] FIG. 3 shows another embodiment of the manhole structure according to the present invention.

[0085] The manhole structure 21 is almost the same as the manhole structure 1 except that a waterproof flexible joint 24 for manhole structure is used.

[0086] The waterproof flexible joint 24 comprises a rigid cylindrical portion 25 and a cylindrical flexible portion 26.

[0087] The cylindrical flexible portion 26 comprises a covering portion 26a to cover a outer periphery of a pipe 23, a fixing portion 26b to be fixed to a manhole 22 and a connecting portion 26c connecting the covering portion 26a to the fixing portion 26b.

[0088] The covering portion 26a at an inner side of the cylindrical flexible portion 26 is fixed to a pipe 23 as a projected pipe by means of a tightening band 29.

[0089] Protective members 33a and 33b are inserted between the rigid cylindrical portion 25 and the covering portion 26a and among an inner mold frame 34 for the manhole filler, and the connecting portion 26c, respectively.

[0090] The manhole filler such as concrete is poured between an earth-retaining casing 31 as an outer mold frame and an inner mold frame 34, thereby forming a concrete wall of the manhole.

[0091] In the manhole structure of FIG. 3, a jaw portion 27 is provided at the fixing portion 26 on the outer side of the cylindrical flexible portion 26, and the non-vulcanizing butyl rubber or water-swelling sealant 28 is set at a surface of the jaw portion 27, which bonds the jaw portion to the manhole filler. Thereby, waterproof can be enhanced.

[0092] In the present invention, waterproof can be also enhanced by attaching the non-vulcanizing butyl rubber or water-swelling sealant to the outer periphery of the fixing portion of the cylindrical flexible portion or the rigid cylindrical portion without providing the jaw portion.

[0093] According to the present invention, the manhole structure in which the manhole and the pipe are joined together via the soft connection can be easily constructed by fixing the waterproof flexible joint for the manhole structure around the pipe and then pouring the manhole filler around the outer periphery of the waterproof flexible joint.

Claims

1. A method for constructing a manhole structure in which a manhole and a pipe are joined together, said method comprising:

preparing a waterproof flexible joint for the manhole structure, said waterproof flexible joint comprising a rigid cylindrical portion and a cylindrical flexible portion, said cylindrical flexible portion comprising a covering portion to be fixed around an outer periphery of said pipe, a fixing portion to be fixed to said manhole and a connecting portion connecting the covering portion to the fixing portion, said fixing portion being fixed to an outer periphery of said rigid cylindrical portion, said connecting portion being made of an elastic material being capable of absorbing a displacement between the manhole and the pipe;

locating the waterproof flexible joint around the outer periphery of the pipe;

fixing the covering portion around the outer periphery of the pipe; and

pouring a filler for the manhole around an outer periphery of the fixing portion.

2. The constructing method set forth in claim 2, wherein said manhole is a concrete manhole cast on site, said manhole is constructed by said filler.

3. The constructing method set forth in claim, wherein said manhole is a make-up constructed manhole, a hole is formed in a peripheral wall of the manhole, and said filler is poured into a space between the outer periphery of the fixing portion and a face of the hole.

4. The constructing method set forth in any one of claims 1 to 3, wherein said fixing portion has a jaw portion, and said jaw portion bites into the manhole.

5. A waterproof flexible joint for use in a manhole structure, said joint being adapted to join a manhole and a pipe and comprising a rigid cylindrical portion and a cylindrical flexible portion, said cylindrical flexible portion comprising a covering portion to be fixed around an outer periphery of said pipe, a fixing portion to be fixed to said manhole and a connecting portion connecting the covering portion to the fixing portion, said fixing portion being fixed to an outer periphery of said rigid cylindrical portion, said connecting portion being made of an elastic material being capable of absorbing a displacement between the manhole and the pipe, the manhole being constructed by pouring a manhole filler around the outer periphery of the filing portion.

6. A manhole structure constructed by the method according to any one of claims 1 to 4, said manhole structure comprising a manhole and a pipe joined together.

7. A manhole structure comprising a manhole, a pipe and a waterproof flexible joint for the manhole structure, the manhole and the pipe being joined together by the waterproof flexible joint, said joint being adapted to join a manhole and a pipe and comprising a rigid cylindrical portion and a cylindrical flexible portion, said cylindrical flexible portion comprising a covering portion to be fixed around an outer periphery of said pipe, a fixing portion to be fixed to said manhole and a connecting portion connecting the covering portion to the fixing portion, said fixing portion being fixed to an outer periphery of said rigid cylindrical portion, said connecting portion being made of an elastic material being capable of absorbing a displacement between the manhole and the pipe, said covering portion being fixed to an outer periphery of said pipe, and a filler for the manhole being poured around said fixing portion.