JP4308363B2 - Flexible joint - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flexible joint used for pipes such as box culverts and shield tunnels buried in the ground or underwater, wall surfaces of buildings, and the like, and prevents the intrusion of filler into the recesses of the flexible joint. The present invention relates to a flexible joint capable of reliably ensuring flexibility.
[0002]
[Prior art]
Conventionally, flexible joints that allow relative displacement between pipe bodies due to crustal movements and the like to stop groundwater and the like have been used at joints such as box culverts. As this type of flexible joint, as shown in FIG. 4, a watertight mounting portion 3 with a tubular body 5 is provided at both ends of a belt-like elastic member 2, and the space between both watertight mounting portions 3, 3 is semicircular. It has been known. Here, in the concrete pipe body 5 to which the flexible joint 1 is attached, a steel frame body 6 having an L-shaped cross-section is generally embedded in an end portion thereof. Then, the watertight mounting portions 3 and 3 at both ends of the flexible joint 1 are connected to the adjacent L-shaped steel frame bodies 6 and 6 with the nuts 7 and 7 in a watertight manner, thereby allowing a relative displacement while allowing joints. The part 8 is covered.
[0003]
That is, the flexible joint 1 here allows relative displacement in each direction of the concrete pipe 5 by the belt-like elastic member 2, and also prevents leakage of groundwater or the like. Such a function of the flexible joint 1 is exhibited only when the recess 4 formed by the belt-like elastic member 2 is present.
[0004]
However, when concrete is cast on the back side of the L-shaped steel frame 6 to form the tube 5, if the concrete enters the recess 4 of the flexible joint 1 and hardens, the belt-like elastic member 2 is free. Cannot be deformed, and flexibility cannot be exhibited. Therefore, in order to prevent the intrusion of concrete into the concave portion 4, the joint portion 8 is filled with a joint material 9 made of foamed rubber or bitumen material. The joint material 9 may move due to the placement pressure or the like, and the concrete may enter and flexibility may be impaired.
[0005]
[Problems to be solved by the invention]
The present invention is an improvement of such a conventional flexible joint, and when injecting a filler such as concrete, it prevents intrusion into the concave portion of the flexible joint so that the original function can be reliably maintained and exhibited. An object of the present invention is to provide a flexible joint.
[0006]
[Means for Solving the Problems]
The present invention has been made to solve the above problems, the gist of which is attached at the time of pouring concrete , embedded in the end of the continuous wall, and a steel frame constituting a joint part The cover is made of a band-shaped elastic member that is fixed to the steel frame, has a recess across the joint, and is open on the opposite side of the joint, and is provided with a lid-like body on the joint that prevents concrete from entering the recess. This relates to a flexible joint. And, the belt-like elastic member is a semicircular or bellows-like, made of fiber reinforced rubber, and the lid-like body is an air bag that adheres tightly in the recess, The present invention relates to a flexible joint that is a closed-cell foam that adheres closely to the inside of the recess, or is an elastic thin plate that covers the surface of the recess.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The flexible joint of the present invention is composed of a band-shaped elastic member having a concave portion, prevents the filler from entering the concave portion when the filler is injected, and the tubular body due to crustal deformation or the like in the joint portion such as a box culvert The occurrence of relative displacement between them can be reliably allowed. In addition, the flexible joint of the present invention is not limited to a tubular body, and can be widely used as long as it is a portion where relative displacement occurs, such as a joint portion of a building pressure plate.
[0008]
Here, the concave portion means a shape capable of exhibiting flexibility, specifically, a semicircular shape or a bellows shape. That is, the semicircular shape has one concave portion, and the bellows shape has a plurality of concave portions. However, in order to allow the relative displacement of the joint portion, the distance between the attachment portions on the flexible joint side (path) may be longer than the linear distance between the attachment portions on the wall surface side, It is not limited to a semicircular shape or a bellows shape, and it can be formed into a substantially cross-shaped cross-section by providing a folded portion, or has irregular wrinkles. In addition, the bellows-like thing may be deformed from a bellows shape to a semicircular shape by the action of groundwater pressure, but even in this case, there is no change in the function of the flexible joint. Needless to say.
[0009]
Moreover, as a strip | belt-shaped elastic member, although soft resin, rubber | gum, etc. can be used, it is preferable to set it as the rubber | gum especially reinforced with nylon or the polyester fiber. This is because the belt-like elastic member can be deformed in shape, but does not expand and contract itself, easily deforms, and withstands groundwater pressure or the like.
[0010]
Next, the lid-like body provided in the recess prevents the filler from entering the recess. That is, even when a pressure or the like at the time of placing concrete is applied, the space of the recess is secured and the flexibility is maintained. Specifically, an air bag or a closed cell foam that adheres closely to the inside of the concave portion, an elastic thin plate that covers the surface of the concave portion, or the like can be applied. Here, the air bag is to secure a space necessary for flexible deformation by its air chamber, and the closed cell foam is to ensure flexibility by bubbles while preventing the intrusion of the filler, The elastic thin plate completely prevents the filler from entering the recess.
[0011]
Further, the lid-like body can be molded not only in advance into the recess on the injection side of the filler but also integrally formed with the belt-like elastic member by adhesion or vulcanization. However, these lid-like bodies need only adhere to the recesses without gaps during the injection of the filler, and have sufficient strength to cover the surface of the recesses. There is no problem even if it is peeled from the inside of the recess, detached from the surface of the recess, or broken.
[0012]
【Example】
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view showing a flexible joint 1 of the present invention. Here, the flexible joint 1 is attached so as to cover the joint portion 8 of a tubular body (continuous wall) 5 formed by placing concrete (filler) on the back side of the steel frame body 6. That is, watertight attachment portions 3 with the steel frame 6 are provided at both ends of the belt-like elastic member 2 and are fixed to the anchor bolts with nuts 7. However, it can be attached by bonding or the like regardless of bolts and nuts.
[0013]
And the fiber reinforcing material shown with a dotted line is inserted in the inside of the strip | belt-shaped elastic member 2, and it is set as the strength member. Further, the distance (path) between the two watertight mounting portions 3, 3 of the belt-like elastic member 2 is semicircular so as to be longer than the linear distance L between the mounting portions of the adjacent steel frame bodies 6, 6. A recess is formed. Therefore, even if relative displacement occurs in the tubular body 5 due to crustal movement such as ground subsidence or earthquake, the belt-like elastic member 2 follows the shape deformed, and the displacement can be sufficiently allowed.
[0014]
In addition, an air bag (lid body) 10 that is in close contact with the gap-shaped elastic member without gaps is inserted in advance to prevent the concrete from entering the recess when placing concrete. That is, the pipe body 5 is formed by filling the joint portion 8 with the joint material 9 and then casting concrete on the back side of the steel frame 6. Even if the joint material 9 moves due to the installation pressure, the air bag 10 acts as a barrier so that the concrete does not enter the concave portion, and the flexible joint 1 is ensured with a space necessary for flexible deformation. In other words, the flexible performance can be exhibited.
[0015]
Therefore, in the present invention, since it is not necessary to use the joint material 9 for the purpose of preventing the concrete from entering the concave portion, it is not necessary to secure the mounting accuracy of the joint material 9 in the joint portion 8 and the workability is improved. Further, the joint material 9 also has a role of preventing the adjacent pipe bodies 5 from being integrated with each other in the concrete. However, in the present invention, if the joint of the pipe bodies 5 can be prevented, the joint material 9 can be prevented. It is also possible to omit itself.
[0016]
The concrete placed is hardened in the state shown in FIG. 1 by the air bag 10, but if it is hardened, even if a gap is formed between the recess and the air bag or the air bag 10 is punctured or the like. There is no problem in the flexibility performance.
[0017]
Moreover, FIG. 2 is sectional drawing which shows the Example which applied the flexible joint in this invention to the foundation of the pressure | voltage resistant board of a building. That is, in FIG. 2, the lower wall plate 11 and the upper wall plate 12 are connected by the flexible joint 1. Further, a precast concrete 14 is placed between the lower wall plate 11 and the natural ground 13. Then, post-cast concrete (not shown) is placed between the upper wall plate 12 and the natural ground 13.
[0018]
However, since the closed-cell foam 10 'that is in close contact with the gap in the flexible joint 1 in FIG. 3 is inserted in advance, the intrusion of the concrete into the recess when the post-cast concrete is placed is prevented. The Therefore, after the placement of post-cast concrete, the flexibility of the flexible joint 1 is exhibited by the deformation of the closed cell foam 10 '.
[0019]
Furthermore, FIG. 3 is sectional drawing which shows the Example which applied the flexible joint in this invention to the primary water stop part of the flexible segment. That is, in FIG. 3, the segments 15 and 15 are connected by the flexible joint 1, and the recesses are covered with the elastic thin plate 10 "made of rubber. Even if concrete is poured back into the concrete, the concrete does not enter the recess, and flexibility is exhibited.
[0020]
The elastic thin plate 10 ″ may be attached to the surface of the concave portion by adhesion as shown in FIG. 3, but may be sandwiched between the belt-like elastic member 2 and the segment 15 to cover the concave portion. The elastic thin plate 10 ″ can withstand the concrete pouring pressure, but can be easily expanded or contracted when the relative displacement occurs between the segments 15 and 15, or the flexible joint 1 can be broken. It is necessary to secure.
[0021]
【The invention's effect】
The present invention is a flexible joint used for a joint portion of a continuous wall formed by injecting a filler on the back side, and is composed of a band-shaped elastic member having a recess across the joint, and the filler enters the recess This is a flexible joint provided with a lid-like body that prevents the intrusion of concrete and other fillers into the concave portion of the flexible joint, ensuring that the space necessary for flexible deformation is secured. The function can be reliably maintained and exhibited. Moreover, since it is not necessary to ensure the mounting accuracy of the joint material, the workability can be improved, and further, the joint material itself can be omitted.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a flexible joint according to the present invention.
FIG. 2 is a cross-sectional view showing another embodiment of the flexible joint according to the present invention.
FIG. 3 is a cross-sectional view showing still another embodiment of the flexible joint according to the present invention.
FIG. 4 is a cross-sectional view showing a flexible joint in a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Flexible joint 2 ... Strip | belt-shaped elastic member 3 ... Mounting part 4 ... Recessed part 5 ... Continuous wall (tubular body)
6. Steel frame 7 Nut 8 Joint 9 Joint material 10, 10 ', 10 "Lid (air bag, closed cell foam, elastic thin plate)
11. Continuous wall (lower wall plate)
12 ... Continuous wall (upper wall plate)
13 ··················· 14 ··················· 15

Claims (6)

Use joints is a joint of a continuous wall formed by injecting concrete into the back, an imperial Ru flexible joint mounted upon injection of the concrete,
A steel frame that is embedded in the end of the continuous wall and forms a joint, and a belt-like elasticity that is fixed to the steel frame, has a recess across the joint, and is open on the opposite side of the joint A flexible joint comprising a member and a lid-like body that prevents concrete from entering the concave portion on the joint portion side .   The flexible joint according to claim 1, wherein the belt-like elastic member is a semicircular member and is made of fiber reinforced rubber.    The flexible joint according to claim 1, wherein the belt-like elastic member has a bellows shape and is made of rubber reinforced with fibers.    The flexible joint according to any one of claims 1 to 3, wherein the lid-like body is an air bag that adheres tightly in the recess.    The flexible joint according to any one of claims 1 to 3, wherein the lid-like body is a closed-cell foam that adheres closely to the recess.    The flexible joint according to claim 1, wherein the lid-like body is an elastic thin plate that covers a surface of the concave portion.

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