JPH06248683A - Joint of culvert - Google Patents

Abstract

PURPOSE:To prevent frame bodies from being corroed and improve the durability by extending a part of guard members in space around the internal circumference of second ;even steps so as to cover the circumferential flanges of the frame bodies. CONSTITUTION:The internal circumference side flanges 4c and 4c' of frame bodies 4 and 4' are so arranged that they are extended to the circumference of second uneven steps 5 and 5' formed in the internal circumference side nearer than first uneven steps 3 and 3' in the ends of a pair of culverts 1 and 1'. After that, guard members 9 and 9' preventing swelling deformation in the direction of the axis of a flexible cut-off member 6 formed in a short cylindrical shape from an elastic material such as rubber/synthetic resin, etc., are provided. A part of the guard members 9 and 9' are extended in space around the circumference of the second uneven steps 5 and 5' so as to cover the internal circumference side flanges 4c and 4c'. According to the constitution, the surface of the internal circumference side flanges 4c and 4c' of the frame bodies 4 and 4' can be so prevented that it is not directly exposed to atomospheres in the culverts 1 and 1'.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underdrain joint used for connecting underdrain such as water and sewers, subways, common ditches, and caves.

[0002]

2. Description of the Related Art In a conventional underdrain joint, a cylindrical frame is anchored to the opposing ends of a pair of cylindrical underdrain which are opposed to each other, and a short tube is formed from an elastic body such as rubber or synthetic resin. Both ends of the flexible water blocking member formed in a shape are watertightly attached to the inner peripheral surface of the frame to absorb relative displacement of the underdrain due to uneven settlement of the ground, and between these underdrains. There is a type that is designed to stop water.

When such an underdrain joint is used to connect underdrains buried in the ground where external water pressure such as groundwater pressure acts, the flexible water stop member bulges and deforms inward. There is a possibility that the durability of the flexible water blocking member may be reduced or the flexible water blocking member may be damaged.

[0004] Therefore, as a joint of the underdrain for preventing such inward bulging deformation of the flexible water blocking member, there is one disclosed in Japanese Patent Publication No. Sho 63-58982 proposed by the present applicant. This joint is fitted with one, as shown in the cross-sectional view of FIG.
It is formed into a short tubular shape made of an elastic material such as rubber or synthetic resin, straddling step portions b and b ′ formed on the inner peripheral surfaces of the ends of the pair of underdrain a and a ′ which face each other. A flexible water blocking member e having an annular constricted portion c in the center and further having anchoring flange portions d and d ′ extending from both sides of the constricted portion c is fixed at the fixing flange portions d and d ′. Step b,
In the space formed between b ′ and the flexible water blocking member e, protective materials f and f ′ for preventing the flexible water blocking member e from bulging and deforming in the axial direction are arranged. is there.

This joint is provided with frame bodies g and g'fixed to the step portions b and b ', and these frame bodies g and g'are on the outer peripheral side facing the fixing flange portion of the flexible water blocking member. The flange members h and h ', the end surface portions i and i'facing the inner side surfaces of the protective materials f and f', and the inner surface of the underdrain a and a'are substantially flush with the inner surface of the underdrain. The exposed inner peripheral side flange portion j,
j ′ and. Note that k is a joint material.

According to this joint, even if a large external water pressure is applied to the flexible water blocking member e, the underdrain a,
It is possible to effectively prevent the swelling deformation of a'in the axial direction, and it is widely used in various underdrains at present.

[0007]

Generally, the inside of the underdrain such as water supply and sewerage, common ditch, etc. has extremely high humidity, and hydrogen sulfide is generated in the sewer, which is an environment where metal corrosion is severe. Regarding the joint of the underdrain described in Japanese Patent Publication No. 63-58982, in the currently used ones, iron frames are used as the frame members g and g '.
Regarding the surfaces of the inner peripheral side flanges j and j'exposed inside the underdrain, at present, corrosion is dealt with by painting, SUS plating, etc., but there is a demand for improving the durability of the skeleton concrete constituting the underdrain. At the same time, there is an increasing demand for improved durability of underdrain joints, and the countermeasures such as painting and plating as described above are not sufficient as corrosion countermeasures for many years, and the corrosion of the frame body is expected to continue for a longer period of time. It would be desirable to provide an underdrain joint without the risk of.

The present invention has been made in order to solve the problems of the above-mentioned conventional underdrain joints, and even if the frame is installed for a long time in a highly humid underdrain, the frame body is not corroded. The present invention seeks to provide an improved underdrain joint that is unlikely to occur.

[0009]

Means for Solving the Problems An underdrain joint for achieving the above object of the present invention is fixed to a first step portion formed on the inner peripheral surface of the end portions of a pair of opposed underdrain pipes. An annular outer peripheral side flange part, an end face part extending from the outer peripheral side flange part toward the shaft center of the underdrain, and an inner peripheral side of the step part from the end face part at the end parts of the pair of underdrain A frame body having an annular inner peripheral side flange portion extending to the peripheral surface of the formed second step portion, and a short tubular shape made of an elastic material such as rubber or synthetic resin, and having an annular constriction in the center A flexible waterproof member having a portion and further extending from both sides of the constricted portion and fixed to the outer peripheral side flange portion of the frame body, an end face portion of the frame body, and the flexible water blocking member. The flexible water blocking member is disposed in a space formed between the water blocking member and prevents the flexible water blocking member from bulging in the axial direction. And a protective material to a portion of said protective material, characterized in that so as to cover the inner flange portion of the frame body extending into the space of the peripheral surface vicinity of the second step portion.

[0010]

The flange on the inner peripheral side of the frame body is arranged so as to extend to the peripheral surface of the second stepped portion formed on the inner peripheral side of the first stepped portion at the ends of the pair of underdrains. Since a part of the protective material covers the inner peripheral side flange and extends into the space near the peripheral surface of the second step portion, the surface of the inner peripheral side flange of the frame body is directly exposed to the atmosphere in the underdrain. Since it is not exposed, there is no risk of corrosion of the frame even if the joint is left for a long time in a high humidity underdrain.

[0011]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 shows an underdrain joint 1 according to the present invention.
FIG. 2 is a sectional view of an embodiment, FIG. 2 is a perspective view of an underdrain to which the joint of the present invention is applied, and FIG. 3 is a partially enlarged perspective view of a push plate.

In FIG. 2, reference numerals 1 and 1'denominate concrete conduits having a circular cross section. The opposing ends of the pair of underdrain 1, 1 ′ are connected to each other by the underdrain joint 2 according to the present invention.
Connected by.

The underdrain joint 2 is, as shown in FIG.
The stepped portion 3 is formed on the inner peripheral surface side edge of the opposite ends of the underdrain 1, 1 ′.
3'is formed and the cylindrical frame bodies 4 and 4'are fixed. Although FIG. 2 is shown in a cross-sectional view in which the cutting position is shifted left and right, in reality it is left-right symmetry, so some reference numerals are omitted on the left and right sides, but for the sake of explanation, it is assumed that they are left-right symmetry. .

Since the shape of the frame body 4'and the structure for attaching it to the underdrain 1'are exactly the same as those of the frame body 4, the reference numerals used for the frame body 4 and the like will be denoted by the numbers with dashes. The description of ′ etc. is omitted.

The frame body 4 is made of iron, and has an annular outer peripheral side flange portion 4a fixed to a first step portion 3 formed on the inner peripheral surface of the end portion of the underdrain 1 and an outer peripheral side flange portion 4a. The end surface portion 4b extending toward the axial center of the first step portion 4 and the peripheral surface 5a of the second step portion 5 formed on the inner peripheral side of the first step portion 3 at the end portion of the underdrain 1 from the end surface portion 4b. It has an annular inner peripheral side flange portion 4c that extends. 4d is the outer flange 4
It is a rising portion protruding outward from a.

The outer peripheral flange portion 4 of the frame bodies 4 and 4 '
A flexible water blocking member 6 made of rubber, synthetic resin or the like and formed in a short tube shape is disposed between a and 4a '. The flexible water blocking member 6 has an annular constricted portion 6 having a substantially U-shaped cross section at the center thereof.
a, and the outer circumference of the constricted portion 6a is an annular recess 6c that opens outward.

Anchoring flange portion 6 extending from both sides of the constricted portion 6a and closely contacting with the outer peripheral flange portion 4a of the frame body 4.
b is integrally formed.

The anchoring flange portions 6b provided on both sides of the flexible water blocking member 6 and extending in the axial direction are formed by screwing a nut 7 into a bolt 14 penetrating this portion and attaching the nut 7 and the anchoring flange portion. By interposing a pressing plate 8 between the pressing plate 8 and 6b and tightening a nut 7, the pressing plate 8 is brought into close contact with the inner peripheral surface of the outer peripheral flange portion 4a of the frame body 4, and is fixed in a watertight manner.

As shown in FIG. 3, the push plate 8 has bolts 1
4 through holes 8a are provided at appropriate intervals. Also, the push plate 8
Threaded portions 8b are provided on one surface at appropriate intervals. In the present embodiment, the threaded portion 8b is shown by welding a bulky bolt, but the invention is not limited to this, and the protective material 9 described later such as one in which the push plate 8 is directly threaded is screwed into the bolt 10. Anything that can be fastened to the push plate 8 by fitting them together may be used.

Further, the threaded portion 8b is for fastening the protective member 9 with the bolt 10, and since a large external force does not act thereon, it may be smaller than the number of the bolt insertion holes 8a.

A protective material 9 is provided in the space formed between the frame body 4 and the flexible water blocking member 6.

The protective material 9 has a push plate 8 and a screwing portion 8 on the outer peripheral end surface.
A groove 12 for accommodating the nut b and the nut 7 is provided, and a groove 13 for accommodating the head of the bolt 10 is provided on the inner peripheral end surface 9b.

The protective member 9 is provided with a bolt insertion hole (not shown) for inserting the bolt 10.

The outer peripheral end surface of the protective member 9 contacts the anchoring flange portion 6b of the flexible water blocking member 6, the outer surface 9c contacts the end surface portion 4b of the frame body 4, and the inner side surface of the flexible water blocking member 6. Constriction 6
It abuts the side surface of a and is indirectly fixed to the outer peripheral flange portion 4 a of the frame body 4. That is, the protective material 9 is the bolt 10
Is fixed to the outer peripheral flange portion 4a of the frame body 4 by the fastening bolts 14 and nuts 7 and is indirectly fixed to the outer peripheral flange portion 4a.

In this embodiment, the grooves 12 and 13 are shown to be continuous, but the present invention is not limited to this and may be discontinuous.

The material of the protective material 9 has sufficient strength to support the flexible water blocking member due to external water pressure and prevent its bulging and deformation, and it also corrodes over a long period of time due to the high humidity atmosphere inside the underdrain. It is necessary that the material is not present, and rubber, synthetic resin, hard foam, etc. are preferable.

A space formed near the peripheral surface 5a of the second step portion 5 of the underdrain 1 so that a part 9a of the protective material 9 on the inner peripheral surface side covers the inner peripheral flange portion 4c of the frame body 4. It is formed so as to project inward. As a result, the inner peripheral surface of the inner peripheral side flange portion 4c of the frame body 4 is not directly exposed to the atmosphere in the underdrain 1 and corrosion is prevented from occurring for a long period of time.

Since the protective member 9 is fixed to the push plate 8 by the bolts 10, it can be detached from the inside of the underdrain 1 with a tool such as a torque wrench, and by removing the protective member 9, the flexible water blocking member can be removed. Replacing 6 can also be done easily.
However, if this is not necessary, it is possible to prevent corrosion of the head of the bolt 10 by, for example, fitting a cap into the groove 13 in which the head of the bolt 10 is accommodated or filling resin. Good.

Reference numeral 16 in the drawing denotes an anchor having one end welded to the head of the fastening bolt 5 and embedded in the axial direction of the underdrain 1.

The anchor 16 more firmly secures the frame 4 to the underdrain 1
The frame 4 is not limited to the one in the embodiment as long as it is used for fixing to the end of the
The method of coupling with and the shape are arbitrary.

A joint material 17 is a sponge member made of rubber, synthetic resin or the like for preventing dirt and sand from entering the recess 6c of the flexible water blocking member 6 and allowing relative movement between the underdrain 1 and 1 '. Is.

The push plate 8 and the protective member 9 are preferably divided into a plurality of pieces in consideration of handling and the like.

Next, the function of the joint 2 having the above structure will be described. Even if the underdrain 1, 1 ′ is buried in the ground where groundwater pressure acts, the flexible water stop member 6 for water stopping connecting these prevents leakage into the underdrain 1, 1 ′. Moreover, the flexible water blocking member 6 has the constricted portion 6a at the center, and the underdrain 1, 1 '
A large inward deformation is hardly generated.

In addition, because the ground is unevenly submerged, the underdrain 1,1 '
Is relatively displaced, the constricted portion 6 of the flexible water blocking member 6
a extends and absorbs the displacement of the underdrain 1,1 '. Further, since the flexible water blocking member 6 has the constricted portion 6a having a U-shaped cross section, therefore, the flexible water blocking member itself of the flexible water blocking member 6 associated with the displacement of the underdrain 1, 1 '. Almost no internal stress is generated in the flexible water blocking member 6 which has a small elongation and impairs the durability, and the displacement resistance of the joint is very small.

A protective material 9 is provided in the space formed between the frame 4 and the flexible water blocking member 6, and the inner surface of the protective material 9 is the side surface of the constricted portion 6 a of the flexible water blocking member 6. Since the flexible water blocking member 6 is in contact with the external water pressure, the flexible water blocking member 6 is prevented from bulging and deforming in the axial direction of the underdrain 1 by the protective material 9 and is supported by the external water pressure. As a result, since the flexible water blocking member 6 alone can maintain a small withstand pressure width for receiving an external pressure, the load on the flexible water blocking member 6 can be reduced, and the displacement of the flexible water blocking member 6 that tends to extend toward the inside of the underdrain is protected. Since it is dispersed and supported at the contact portion with the material 9, a large stress is generated when a large external pressure is applied, and the increase in load on the anchoring flange portion 6b of the flexible water blocking member 6 that impairs watertightness is reduced. To do.

The joint 2 having the above-described structure has no portion directly exposed to the atmosphere in the underdrain of the middle and high humidity of the frame 4 made of iron, and the constituent elements of the joint 2 are directly exposed to the atmosphere in the underdrain. Flexible waterproofing member 6 made of a material that is resistant to corrosion such as synthetic resin 6
Since only the protective material 9 is used, the durability of the joint 2 as a whole can be significantly improved.

In the above embodiment, the protective material 9 is formed as a solid material, but it is not limited to this, and it may be hollow or may have a groove on the outer surface to reduce the weight of the protective material. Various shapes can be adopted.

If necessary, a reinforcing cloth may be embedded in the flexible water blocking member to enhance the strength.

In the above embodiment, an example in which the underdrain joint 2 is applied to the connection of a concrete underdrain has been shown, but the underdrain joint 2 is not limited to a concrete underdrain and is also applied to other underdrain. You may.

The cross-sectional shape of the underdrain 1, 1'is not limited to a circle, and may be any of ellipse, quadrangle and polygon, and the underdrain 1, 1'may be an integral product. ,
The dividing member may be assembled and configured.

Further, the flexible water blocking member is not limited to the one having a straight cylindrical shape, but may have various shapes such as a bellows shape and a cylindrical body having a hollow portion in the circumferential direction.

[0042]

As described above, according to the present invention, the inner peripheral side flange of the frame body is formed on the inner peripheral side with respect to the first stepped portion at the ends of the pair of underdrains. The frame is provided so as to extend to the peripheral surface of the step portion, and a part of the protective material extends into the space near the peripheral surface of the second step portion so as to cover the inner peripheral side flange. The surface of the inner flange of the body is not directly exposed to the atmosphere in the underdrain, so there is no danger of corrosion to the frame even if it is left installed in the underdrain with high humidity for a long time It is possible to provide an excellent underdrain joint.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a joint for an underdrain according to the present invention.

FIG. 2 is a perspective view of an underdrain to which the embodiment is applied.

FIG. 3 is a partially enlarged perspective view of a push plate.

FIG. 4 is a cross-sectional view showing an example of a conventional underdrain joint.

[Explanation of symbols]

 1,1 'Underdrain 2 Joint 3 First step portion 4 Frame 4a Outer peripheral side flange portion 4b End surface portion 4c Inner peripheral side flange portion 5 Second step portion 6 Flexible water stop member 6a Constricted portion 6b Anchored flange portion 9 Protective material 9a Part of protective material

Claims (1)

[Claims] 1. An annular outer peripheral flange portion fixed to a first step portion formed on an inner peripheral surface of an end portion of a pair of opposed underdrain, and an outer peripheral flange portion and a shaft of the underdrain. An end surface portion extending toward the center, and an annular inner circumference extending from the end surface portion to the peripheral surface of a second step portion formed on the inner peripheral side of the step portion at the end portions of the pair of underdrain Formed in a short tubular shape made of an elastic material such as rubber and synthetic resin, and a frame body having a side flange portion,
And having a ring-shaped constricted portion in the center, further extending from both sides of the constricted portion, a flexible water stop member having an anchoring flange portion fixed to the outer peripheral side flange portion of the frame body, of the frame body A protective member disposed in a space formed between the end surface portion and the flexible water blocking member to prevent the flexible water blocking member from bulging and deforming in the axial direction; The underdrain joint is characterized in that the portion extends into the space near the peripheral surface of the second step portion so as to cover the inner peripheral side flange portion of the frame body.