JP3197448B2 - Pin joint mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a pin joint for joining concrete structures, such as segments, which are joined together to form a cylindrical tunnel wall, for example, to a joint end face of the concrete structure. Regarding the structure.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional example of a structure in which concrete segments are joined together using a round bar-shaped pin joint. In this case, the pin joint 10 projecting from the joining end face 1a of one segment (concrete structure) 1 to be joined is attached to the other segment 1
The segments 1 are joined to each other by being inserted and locked into the concave locking member 20 provided on the bonding end face 1b.

[0003] The pin joint 10 is a rod-like body having a uniform diameter and having a threaded portion 10a formed at one end. The threaded portion 2a is screwed into an insert fitting 15 which is a cylindrical threaded material embedded in the joint end surface 1a. , The other end protrudes from the joint end face 1a by a predetermined length.

[0004] One concave locking member 20 is a casing 21 having a tapered peripheral wall 21a and a flat bottom 21b.
In this configuration, a wedge member 22 having a hollow insertion hole 22a is housed between elastic members 24. The wedge member 22 is divided into a plurality (about two to four pieces) of pieces 25 by a dividing surface along the axial direction, and can slide on the joining end face 1b side. (The insertion hole 22a) is narrowed. The resilient member 24 has an annular elastic portion 24b formed around a central protrusion 24a protruding inward.

[0005] To join the segments 1, the pin joint 10 is simply inserted into the insertion hole 22 a of the wedge 22. Then, the distal end of the pin joint 10 hits the central projection 24 a of the resilient member 24 and dents, and at the same time, the annular elastic portion 24.
b slides each piece 25 to the joining end face 1b side, and as a result, each piece 25 sandwiches and locks the pin joint 10. In this state, the joint end surfaces 1a and 1b of both segments 1 are set to be in close contact.

[0006]

Underground structures are usually subjected to pressure due to earth pressure, earthquakes, etc., and when this kind of pressure is applied to the above-mentioned segment 1, the seam (joint) is displaced. . In addition, the displacement of the seam may be caused by the weight of the segment. When a pressure (stress) for shifting the joint is applied, in the above-described pin joint structure, the connection state between the pin joint 10 and the concave locking member 20 is extremely fixed, and a buffering action for protecting the member is not provided. Since it does not work, for example, a problem is supposed that a stress is transmitted directly from the pin joint 10 to the segment 1 via the insert fitting 15 and cracks are generated in the concrete around the insert fitting 15.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pin joint mounting structure capable of preventing cracks in a concrete structure.

[0008]

According to the present invention, as a means for achieving the above object, a pin joint protrudingly attached to one joint end face is inserted into a concave locking member provided on the other joint end face. In joining concrete structures by locking, the pin joint is attached to the one joint end face, and is provided along the joint end face.
And a plate which is elastically deformed by receiving a predetermined load, and a pin insertion hole formed substantially at the center of the plate.
Hole was fixed to the plate in line with the pin insertion hole
A holder having a nut member is installed on the one joint end surface, and one end of the pin joint is inserted into the pin insertion hole.
And screwed into the nut member, the pin joint is fixed to the plate in a state protruding from the one joint end face, and the plate is elastically deformed by receiving a force acting on the joint pin. And

In addition, a cavity is formed around the nut member, or the nut member is fitted in a case made of a resilient material such as resin.

[0010]

According to the pin joint mounting structure of the present invention, when a stress causing a displacement at the seam of the concrete structure is applied, the stress is buffered by the deformation of the plate and does not act directly on the concrete, and cracks are generated. Is prevented beforehand. If the mounting part for attaching the pin joint is constituted by a pin insertion hole formed substantially in the center of the plate and a nut member fixed to the plate by matching the screw hole with the pin insertion hole,
The structure is simple and easy to manufacture. In the structure, if a cavity is formed around the nut member or the nut member is fitted in a case made of a resilient material such as resin, the behavior of the nut member is allowed and the deformation of the plate is not hindered.

[0011]

An embodiment of the present invention will be described below with reference to FIG. 1, the same components as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the pin joint 10 is attached to the holder 30 instead of the insert fitting 15.
This point is different from the conventional one.

The holder 30 includes an elastically deformable plate 31 and a mounting portion 3 provided substantially at the center of the plate 31.
2 is provided. The plate 31 is made of steel and has a rectangular shape, and in the center, a pin insertion hole 33 through which the pin joint 10 can be inserted.
Are formed. Side plates 34 are welded to both ends of one surface serving as the back surface of the plate 31.

The mounting portion 32 includes the pin insertion hole 33, a nut member 36 fixed to the back surface of the plate 31, and a bottomed cylindrical case 37. Nut member 36
Is a cap nut in which only one end of the screw hole 36a is opened,
The screw portion 10a of the pin joint 10 can be screwed into the screw hole 36a, and the screw hole 36a is inserted into the pin insertion hole 33.
The opening edge of the plate 31
Welded to the back of

The casing 37 covers the nut member 36 and has an opening edge welded to the back surface of the plate 31. In this state, an inner surface is formed with an outer surface of the nut member 36 and a cavity 38 to some extent. Thus, the nut member 3
The plate 31 to which the casing 6 and the case 37 are welded is buried at a predetermined position on the joining end face 1a with the surface thereof flush with the joining end face 1a. At the time of embedding, a reinforcing bar 39 for an anchor is welded to the outer surface of the side plate 34 in two upper and lower stages.
Further, a lubricating and releasing material such as grease is applied to the outer surface of the case 37.

In order to attach the pin joint 10 to the holder 30, the screw portion 10 a is inserted into the pin insertion hole 3 of the plate 31.
3 and screwed into the screw hole 36a of the nut member 36 to engage. In this state, the other end portion side opposite to the screw portion 10a protrudes from the joint end surface 1a by a predetermined length.

Then, in order to join the segments 1 together, the wedge member 22 sandwiches and locks the joint pin 10 by simply inserting the pin joint 10 into the insertion hole 22a of the wedge member 22 as described above. This is done by:

As described above, the pin joint 10 is
When the segment 1 is subjected to the stress that the seam shifts due to the pressure due to earth pressure, earthquake, etc.
The stress is buffered by the deformation of the plate 31 of the holder 30. Stress is roughly classified into two types: "separation stress" acting in the direction of separating the segments 1 from each other and "shift stress" acting in the direction of displacing along the joint end surfaces 1a and 1b. When a separation stress is applied, the plate 31
0 and is deformed so as to be separated from the joint end face 1b. When a shear stress is applied, the plate 31 bends around the pin insertion hole 33 and deforms.

These deformations are caused by the side plates 34 of the plate 31.
Occurs in the area between them. Plate 31 is segment 1
Although it is buried in concrete, it is not firmly bonded, and the connection with concrete is lost due to the above-mentioned stress, so that separation or deformation is possible. As described above, the reason why grease or the like is applied to the outer surface of the case 37 as a lubricating and releasing agent is to prevent the case 37 from being bonded to the concrete and preventing the deformation of the plate 31 when a separating stress is applied. . In addition, in the case of a shear stress, the cavity 31 is provided between the nut member 36 and the case 37 and the behavior of the nut member 36 is allowed, so that the plate 31 can be deformed. These prevent the plate 31 from being damaged.

The strength of the plate 31 (depending on the thickness etc.)
Is set so as to buffer the displacement occurring between the segments 1 and to prevent itself from being damaged, and the deformation may be either within the range of elastic deformation or may reach plastic deformation. .

As described above, the stress that causes a shift at the joint of the segment 1 is buffered by the deformation of the plate 31 of the holder 30, and the stress is directly applied to the segment 1.
It does not work on concrete and attenuates greatly, preventing cracks in concrete.

FIG. 2 shows a holder 40 according to another embodiment of the present invention.
Is shown. In this embodiment, a normal nut member 41 having both ends open is used in place of the nut member 36 of one embodiment, and a case 42 made of an elastic resin is used in place of the case 37. The member 41 is fitted in the case 42 without a cavity therebetween.

According to this embodiment, the case 42 fulfills the function of the cavity 38 of the above embodiment. That is, when the above-mentioned shift stress is applied to the nut member 41, the case 42 is deformed by elasticity, so that the plate 31 can be deformed.

[0023]

As described above, according to the pin joint mounting structure of the present invention, a plate elastically deformed by receiving a predetermined load, and a mounting portion provided substantially at the center of the plate are provided. The holder is installed on the joint end face of one concrete structure, and one end of the pin joint is engaged with the mounting portion. The stress is buffered by the deformation of the plate and is greatly attenuated,
As a result, there is an effect that cracks are prevented from occurring in concrete.

[Brief description of the drawings]

FIG. 1 is a side sectional view of one embodiment of the present invention.

FIG. 2 is a side sectional view of another embodiment of the present invention.

FIG. 3 is a side sectional view showing an example of a conventional pin joint structure.

[Explanation of symbols]

1 ... segment (concrete structure), 1a, 1b ...
Joint end face, 10: pin joint, 20: concave locking member, 30
... Holder, 31 ... Plate, 32 ... Mounting part, 33 ... Pin insertion hole, 36, 41 ... Nut member, 38 ... Cavity, 42 ...
Case.

Continued on the front page (72) Inventor Nobuo Suzuki 2-3 Odagashi-cho, Chiyoda-ku, Tokyo Tokyo Obayashi-gumi Tokyo head office (72) Inventor Shoji Okamoto 2-3-Kandajicho, Chiyoda-ku Tokyo Headquarters (56) Reference Literature 52-153323 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16B 5/00-5/12 F16B 37/04 E21D 11/08

Claims (3)

(57) [Claims] When joining a concrete structure by inserting and locking a pin joint protrudingly attached to one joint end face into a concave engaging member provided on the other joint end face, a structure for attaching the joining end face of the one, the plate is elastically deformed by receiving a predetermined load is provided along the joining end face, the shape substantially at the center of the plate
The formed pin insertion hole and the screw hole coincide with the pin insertion hole
And a holder having a nut member fixed to the plate is set on the one joint end face, and the pin is inserted into the pin insertion hole.
Insert one end of the pin joint and screw it into the nut member
The pin joint is fixed to the plate in a state where the pin joint protrudes from the one joint end face, and the plate is elastically deformed by receiving a force acting on the joint pin. Construction. 2. A cavity is formed around the nut member.
The pin joint installation according to claim 1, wherein
Construction. 3. The nut member has elasticity such as resin.
Characterized by being fitted into a case made of material
The pin joint mounting structure according to claim 1.