JP2002070490A - Joint structure of concrete construction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint structure capable of increasing tension resistance so as to prevent the joint ends of a concrete construction from being separated from each other even if tensile force acts between connected concrete constructions and preventing the occurrence of a crack in the concrete construction. SOLUTION: The head of a bolt 7 or a nut 8 is locked with a segment 1 through a flat spring 2, the segment 1 includes a flange plate 3, and the flange plate 3 is clamped with the bolt 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure applied to a joint between segments of a concrete structure forming a tunnel or the like.

[0002]

2. Description of the Related Art As a structure for joining segments of a concrete structure constituting a tunnel or the like, for example, a bolt insertion hole which communicates with the joining end surfaces of the segments when the joining end surfaces of the segments come into contact with each other. Generally, a structure is used in which these segments are joined together by inserting a bolt into a bolt insertion hole of the joint plate where the joint plate is formed, and screwing a nut into the nut.

Underground structures such as tunnels are
It is common to receive pressure due to earth pressure or earthquake, etc. When this kind of pressure is received by the above segment, the joint (joint)
May be shifted. In a conventional segment, when a tensile force is strongly applied to the segments in a direction in which the segments are separated from each other, stress concentrates on a central portion of the joined joint plate, and the joint end faces of the segments are separated from each other, and cracks are generated in concrete. There was a fear of doing.
This is extremely important for water and sewage and water storage tanks that require water tightness, and also extremely important in that the structure of the water and sewage and water storage tank itself is weakened.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a concrete structure having a tensile strength so that even if a tensile force acts between the connected concrete structures, the joining end faces of the concrete structures are not separated from each other. It is another object of the present invention to provide a joint structure capable of preventing the occurrence of cracks in a concrete structure.

[0005]

In order to solve the above-mentioned problems, a joint structure for a concrete structure according to the first aspect of the present invention comprises a segment forming the concrete structure,
A joint structure for a concrete structure which is fastened and fixed to each other by bolts, wherein a head or a nut of the bolt is locked to the segment via a leaf spring.

In the joint structure for a concrete structure according to a second aspect of the present invention, the segment has a flange plate, and the flange plate is fastened by the bolt.

In the joint structure for a concrete structure according to a third aspect of the present invention, a bolt forming a segment forming the concrete structure so as to protrude from one joint end face of the segment is attached to the other segment. A joint structure for a concrete structure which is inserted into and locked to a concave locking member provided on a bonding end face and bonded to the concrete structure, wherein a head of the bolt is locked to the segment via a leaf spring.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
1 and 2 show an example of a joint structure of a concrete structure according to the present invention. The segments 1 constituting the concrete structure are joined to the adjacent segments 1 by the following method. The adjacent segments 1, 1 insert bolts 7 into bolt insertion holes 3 a of the flange plate 3 via leaf springs 2 from bolt boxes 5 for bolting work provided on one of the segments 1. A nut 8 is fastened to the tip 7a of the bolt from the bolt box 5 of the other segment 1 via the leaf spring 2 and joined.

The leaf spring 2 is usually formed of a spring steel such as a square or a rectangle so that its cross section is curved. The size of the leaf spring 2 is formed on the flange plate 3. It is appropriately determined according to the size of the groove 4 formed. Both ends 2 a of the curved shape of the cross section of the leaf spring 2 are directed toward the flange plate 3, and are fitted into grooves 4 formed in the flange plate 3.

The material of the leaf spring 2 is carbon steel, silicon steel, silicon-manganese steel, silicon-chromium steel, manganese-chromium steel, chromium-vanadin steel, silicon-chromium-vanadin steel, silicon-nickel-chromium steel, Nickel-chromium-
It is made of spring steel such as molybdenum steel or molybdenum steel, and is appropriately selected depending on its shape and size.

As shown in FIG. 3, when an external force due to an earthquake or the like is applied to the segment 1, a tensile force acts in a direction in which the segments 1 are separated from each other. The surface 3b is separated. In normal times, the flange plate 3 is joined as shown in FIG. 1, and the shape of the leaf spring 2 at this time is greatly curved. However, when the segments 1 receive an external force and are separated from each other, as shown in FIG. 3, both ends 2 a of the curved shape of the cross section of the leaf spring 2 extend in the direction of the side wall 4 a of the groove 4.

As described above, when the segment 1 is subjected to an external force, both ends 2a of the cross section of the leaf spring 2 extend in the direction of the side wall 4a of the groove 4, and the segment 1
Absorb the stress applied to Thereby, it is possible to prevent the segment 1 from being cracked. The fastening bolts 7 of the segments 1 are made of a material having a short length and a small elongation, so that the stress cannot be sufficiently absorbed. Therefore, using the leaf spring 2 in this way is very effective.

When the segment 1 receives an external force,
In order to make the leaf spring 2 stretch and easily absorb the stress, the surface of the groove 4 is subjected to a surface treatment so that the both ends 2 a of the curved shape of the cross section of the leaf spring 2 become slippery. Further, by fitting the leaf spring 2 into the groove 4, it is possible to prevent the leaf spring 2 from being stretched by receiving a stress, and to obtain a large spring characteristic.

As described above, the segment 1 is formed by using the leaf spring 2.
By joining them, not only can the segment 1 be prevented from cracking, but also the bolt 7 can be prevented from breaking. Therefore, the weakening of the entire concrete structure can be prevented.

Next, FIG. 4 shows another example of a joint structure for a concrete structure according to the present invention. In this example, a structure in which concrete segments 1 are joined to each other using bolts (hereinafter, referred to as “pin joints”) 10 is shown.
In this case, the pin joint 10 protruding and attached to the joining surface 1a of one segment 1 to be joined is inserted and locked into the concave locking member 20 provided on the joining end surface 1b of the other segment 1 so that the segment 1 , 1 are joined together.

The pin joint 10 is a rod having a uniform diameter and a threaded portion 10a formed at one end thereof.
It is inserted from the side a into the insertion hole 11 via two O-rings 12 made of rubber or the like. In addition, the pin joint 10
Is fixed by a washer 16 and a nut 17 previously joined to a side wall 14a of a groove 14 opposite to the insertion hole 11 formed in the bolt box 13. The leaf spring 2 is fitted into the groove 15 on the side of the insertion hole 11 formed in the bolt box 13, and the leaf spring 2 is fixed with the washer 16 and the nut 17, and in this state, the other end of the pin joint 10 is joined. It protrudes from the end face 1a by a predetermined length.

On the other hand, the 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 material 22a is divided into a plurality (about 2 to 4 pieces) of pieces 25 from a division surface along the axial direction, and can slide on the joining end face 2b 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.

To join the segments 1 and 1, the pin joint 10 is simply inserted into the insertion hole 22a of the wedge member 22. Then, the tip of the pin joint 10 hits the central projecting portion 24a of the resilient member 24 and dents, and at the same time, the annular elastic portion 2
4b slides each piece 25 toward the joint end face 1b,
As a result, each piece 25 is engaged by pinching and locking the pin joint 10. In this state, the joint end surfaces 1a and 1b of both segments 1 are set so as to be in close contact.

In the joint structure of this embodiment, first, the pin joint 10
Is inserted into the concave locking member 20, the repulsive force received from the segment 1 on the side where the pin joint 10 is inserted is received by the side wall 14 a of the groove 14. Therefore, the leaf spring 2 may be fitted into the groove portion 14 in order to prevent the segment 1 from being cracked by the repulsive force at the time of joining. When the segment 1 is subjected to an external force due to an earthquake or the like and a tensile force acts in a direction in which the segments 1 are separated from each other, both ends 2 a of the cross-sectional shape of the leaf spring 2 become thicker in the groove 15. The pin joint 10 stretches and / or absorbs stress by the O-rings 12,12,
This prevents the segment 1 from cracking.

As in the example shown in FIG. 1, the surfaces of the grooves 14 and 15 are formed so that when the segment 1 is subjected to an external force, the leaf spring 2 is stretched and the stress is easily absorbed. The both ends 2a of the curved shape of the cross section are surface-treated so as to be slippery. Further, by fitting the leaf spring 2 into the grooves 14 and 15, it is possible to prevent the leaf spring 2 from being stretched by receiving a stress, and to obtain large spring characteristics.

Next, FIG. 5 shows another example of the joint structure of the concrete structure of the present invention. The present embodiment differs from that shown in FIG. 4 in that the casing 31 of the bolt box 30 containing the concave locking member 20 shown in FIG. Further, the pin joint 35 is attached so as to protrude from the joint surface 1a of the segment 1, and is inserted and locked by the concave locking member 20 provided in the bolt box 30 of the other segment 1 to join the segments 1 together. That is the point.

The pin joint 35 has a rod shape having a uniform diameter, and is inserted from the bolt box 30 provided in the segment 1 through two O-rings 12 and 12 made of rubber or the like.
6 is inserted. The head 35 of the pin joint 35
a, the leaf spring 2 is locked to the bottom 31b of the casing of the bolt box 30, a concave locking member 20 is provided at the rear end of the head 35a, and the bolt box 30 is covered with the lid 32 to form a concave. The locking member 20 is fixed.

As shown in FIG. 6, the lid 32 has an insertion hole 32a for the pin joint 10 formed at the center thereof, and has a rectangular outer shape. Further, the shape of the casing 21 of the concave locking member 20 is a square as shown in FIG. 6A or a circular as shown in FIG. 6B.

In the joint structure of this example, similarly to the example shown in FIG. 4, when the pin joint 35 is first inserted into the concave locking member 20, the segment 1 into which the pin joint 35 is inserted is inserted. The repulsive force received from the segment 1 is absorbed by the bottom 21 b of the casing 21 of the concave locking member 20. Further, the repulsive force received from the segment 1 on the side where the pin joint 35 is inserted is absorbed by the leaf spring 2 fitted into the bolt box 30 on the side where the pin joint 35 is inserted. When the segment 1 receives an external force due to an earthquake or the like and a tensile force acts in a direction in which the segments 1 are separated from each other, both ends 2 of the cross-section of the leaf spring 2 have a curved shape.
a extends in the thickness direction of the segment 1 in the groove portion 15 and the pin joint 35 extends and / or the O-ring 1
The stresses are absorbed by 2 and 12 to prevent the segment 1 from cracking.

The surface of the bottom 31b of the casing of the bolt box 30 is formed so that when the segment 1 receives an external force, the leaf spring 2 is stretched and the stress is easily absorbed, as in the example shown in FIG. The both ends 2a of the curved shape of the cross section of the leaf spring 2 are surface-treated so as to be slippery. Further, the leaf spring 2 is connected to the casing 3 of the groove bolt box 30.
By fitting the plate spring 1, the leaf spring 2 is prevented from being stretched by receiving a stress, and a large spring characteristic can be obtained.

[0026]

As described above, in the joint structure of a concrete structure according to the present invention, when an external force due to an earthquake or the like is applied and a tensile force acts in a direction in which the segments are separated from each other, the leaf spring is activated. It can absorb stress, prevent cracks in the segments, and prevent weakening of the entire concrete structure. Further, even if the amount of the material used for the leaf spring is small, a large spring characteristic can be obtained, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a joint structure of a concrete structure according to the present invention.

FIG. 2 is a view illustrating an example of a joint structure of a concrete structure according to the present invention, and is a view illustrating a state where a leaf spring is fitted into a groove formed in a flange plate.

FIG. 3 is a sectional view showing an example of a joint structure of a concrete structure according to the present invention.

FIG. 4 is a sectional view showing another example of the joint structure of the concrete structure according to the present invention.

FIG. 5 is a sectional view showing another example of the joint structure of the concrete structure of the present invention.

FIG. 6 is a view showing the shapes of a lid and a concave locking member used in another example of the joint structure for a concrete structure according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Segment, 2 ... Leaf spring, 2a ... Leaf spring end part, 3 ...
Flange plate, 3a ... bolt insertion hole, 3b ... flange plate joint, 4 ... flange plate groove, 4a ...
Groove side wall, 5, 13, 30 ... bolt box, 6, 16
... washers, 7, 17 ... bolts, 7a ... bolt screw parts,
8 nut, 10, 35 pin joint, 11, 36 insertion hole, 12 O-ring, 14, 15 groove, 14a, 15
a ... groove side wall, 18 ... lid, 31 ... bolt box casing, 32 ... bolt box lid, 32a ... insertion hole, 33
… Anchor reinforcement

Claims (3)

[Claims] 1. A joint structure for a concrete structure in which segments constituting the concrete structure are fastened and fixed to each other by bolts and joined, wherein a head or a nut of the bolt is locked to the segment via a leaf spring. A joint structure for a concrete structure, characterized in that it is made. 2. The joint structure according to claim 1, wherein the segment has a flange plate, and the flange plate is fastened with the bolt. 3. A bolt forming a concrete structure and protruding from one joint end face of the segment and attaching the bolt to a concave engaging member provided on the joint end face of the other segment. A joint structure for a concrete structure to be joined, wherein a head of the bolt is locked to the segment via a leaf spring.