JP2004092288A - Cut-and-cover underground structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint structure for a cut-and-cover underground structure that has high watertightness and prevents a breaking accident even under large displacement. <P>SOLUTION: A cut-and-cover underground structure is buried underground and is equipped with a joint defined by a joint of concrete placing at every unit length so as to follow ground displacement. Water-swelling water stop rubber of extremely large elastic deformation covers in bridging band form the outer perimeter of the joint line forming the joint over substantially equal opposite distances from the joint line to seal the outer perimeter of the joint line, and a protective steel sheet covers the outer perimeter of the water-swelling waters stop rubber, so that the water-swelling water stop rubber blocks water from intruding into the cut-and-cover underground structure and that the protective steel sheet protects the water-swelling water stop rubber from ground variation and the like. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an open-cut underground structure constructed when a road or a railway is laid underground, and more particularly to a water-blocking structure for a joint portion.
[0002]
[Prior art]
FIG. 3 shows an example of a general open-cut underground structure. In the drawing, reference numeral 1 denotes a ground surface, 2 denotes an excavated structure constructed by excavating the ground surface, and 3 denotes an excavated underground structure constructed inside the excavated structure 2.
The excavated underground structure 3 is formed by pouring concrete into a mold inside the cut 2. Since a construction method of constructing the excavated underground structure 3 by repeating the construction of the formwork and the pouring of concrete is adopted, joints (joints) are formed at required distances.
[0003]
Although a joint is unavoidably formed due to the construction method, a joint having the following two functions has been used as a joint.
1. When the ground is displaced due to an earthquake or the like, a joint for displacing the open-cut underground structure 3 following the displacement of the ground,
2. When concrete shrinks and deforms, joints to prevent cracking,
And exists.
The former is generally called a structural joint and is formed at intervals of about 20 to 30 m. The latter are called induction joints and are formed at intervals of about 4 to 6 m. In FIG. 3, reference numeral 4 denotes a structural joint, and reference numeral 5 denotes an induced joint.
[0004]
FIG. 4 shows an example of the structure of the structural joint. The cross section shown in FIG. 4 is a cross section of any one of AA, BB, CC, and DD shown in FIG.
In the case of the structural joint 4, a joint material 6 such as elastite is filled between the structures 3-1 and 3-2, and a reaction force is generated between the structures 3-1 and 3-2. The main reinforcing bar 7-1 is stretched in the circumferential direction of the structures 3-1 and “3-2”, and the distribution bar 7-2 is stretched in the extending direction. The structures 3-1 and 3-2 are connected to each other by a force distributor 7-3 stored in a sheath tube. Both ends of the force distribution bar 7-3 are fixed to the concrete constituting the structures 3-1 and 3-2, and are stored in the sheath tubes at the joints of the structures 3-1 and 3-2. With this structure, when compressive load and tensile load are applied to each of the structures 3-1 and 3-2, the force distribution muscle 7-3 expands and contracts, and thereby each end face of the structures 3-1 and 3-2. The structure is such that an extreme load is prevented from being applied to the portion, and the end face portion is prevented from cracking due to expansion and contraction of the force-feeding muscle 7-3.
[0005]
Reference numeral 8 denotes a water stop plate provided at the joint. As shown in FIG. 6, the water stop plate is constituted by a cavity 8-1 and fins 8-2 protruding from both sides of the cavity 8-1, and is formed of an elastic body such as rubber. It is formed. The cavity part 8-1 is arranged at the joint part, and the fin part 8-2 is inserted and fixed in the concrete constituting the structures 3-1 and 3-2.
FIG. 5 shows a sectional structure of the induction joint 5. In the case of the induced joint 5, the joint is simply constituted by a concrete joint surface, and the water stop plate 8 is inserted across the joint surface.
[0006]
[Problems to be solved by the invention]
In the case of a joint structure using the conventional water stop plate 8, it is difficult to pour concrete tightly in contact with the water stop plate 8 particularly at the fin portion 8-2 at the time of pouring concrete. Often, cavities are formed in concrete. For this reason, there is a disadvantage that the water stoppage is poor. In addition, there is a disadvantage in that when the concrete is poured in close contact with the fin portion 8-2, it takes much time and the workability is poor.
Furthermore, although the water stop plate 8 is made of an elastic material such as rubber, there is also a disadvantage that an accident occurs in which the water stop plate 8 is broken at the time of an earthquake because the elastic deformation amount is insufficient for a large displacement.
[0007]
For this reason, a waterproof rubber having an Ω-shaped cross-sectional shape has been proposed, but a waterproof rubber having an Ω-shaped cross-sectional shape is expensive, and it is economical to use it in large quantities for long-distance excavated underground structures. Difficult.
An object of the present invention is to propose a joint structure of an excavated underground structure having a high water stopping performance, excellent workability at the time of construction, and excellent functions without any breakage accident.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, in an open-cut underground structure buried underground and provided with a joint for each unit length to follow the displacement of the ground, the joint is straddled on the outer periphery of the joint serving as the joint. A cut-off structure that covers the outer periphery of the joint by applying a water-swelling water-stopping rubber in a belt shape over almost the same distance from the joint, and covering the outer peripheral surface of the water-swelling water-stopping rubber with a protective steel plate. Propose an underground structure.
According to a second aspect of the present invention, in the open-cut underground structure according to the first aspect, a water-swelling waterproof rubber is also applied to the inner periphery of the joint, and the inner peripheral surface of the water-swelling waterproof rubber is covered with a protective steel plate. An open-cut underground structure characterized by a structure is proposed.
[0009]
According to a third aspect of the present invention, there is provided the underground underground structure according to any one of the first and second aspects, wherein the water-swelling waterproof rubber is made of non-vulcanized rubber. According to a fourth aspect of the present invention, in any of the excavated underground structures according to any one of the first to third aspects, the excavated underground structures connected at the joint portion are connected to each other by a force bar. Propose an underground structure.
According to a fifth aspect of the present invention, in any of the open-cut underground structures according to any one of the first to fourth aspects, the joints of the open-cut underground structures connected to each other at the joint portion are connected to each other by a distribution muscle stored in a sheath tube. An open-cut underground structure characterized by this is proposed.
[0010]
Action <br/> a structure for sealing the substantially equal intervals in the deposited water expansion water stop rubber joint outer circumference of joint across the joint to at least the outer periphery of the joint to be joint according of the present invention, further water-swelling Since the outer periphery of the water-stopping rubber is covered with the protective steel plate, the sealing performance is high and high water-stopping performance can be obtained.
In particular, when a non-vulcanized rubber is used as the water-swelling waterproof rubber, the non-vulcanized rubber has a high affinity for concrete, and a strong adhesive force can be obtained. As a result, strong sealing performance can be obtained.
[0011]
Further, since the non-vulcanized rubber has a tensile elongation performance of 1000% or more, there is no possibility that a breakage accident will occur even if the joint is largely deformed. As a result, a highly reliable water shutoff structure can be provided.
Furthermore, according to the present invention, since the structure is not inserted into the interior of the concrete, an advantage of good workability can be obtained.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an embodiment of an open-cut underground structure according to the present invention. The cross section shown in FIG. 1 also shows any one of the cross sections AA, BB, CC, and DD shown in FIG. In the present invention, the joint structure according to the present invention is applied at intervals of 4 to 6 m without distinction between the structural joint 4 shown in FIG. 4 and the induction joint 5 shown in FIG.
In the embodiment shown in FIG. 1, the power distribution bar 7-2 is inserted between the structures 3-1 and 3-2, and the structures 3-1 and 3-2 are connected by the power distribution bar 7-2, The outer periphery of the joint is covered with the water-swelling waterproof rubber 11-1 over substantially the same distance over the joint, and the outer periphery of the water-swelling waterproof rubber 11-1 is covered with a protective steel plate 12-1. is there.
[0013]
The non-vulcanized rubber is used as the water-swelling waterproof rubber 11-1. Non-vulcanized rubber has the property of reacting with concrete and hydrating with concrete, and strongly adhering to the concrete surface. Non-vulcanized butyl rubber is straddled over joints and is approximately equidistant (extending direction of structures 3-1 and 3-2), for example, the outer peripheral surfaces of structures 3-1 and 3-2 over a width of about 70 to 80 mm from the joints. To both sides. The thickness is about 20 mm. In the embodiment shown in FIG. 1, the water-swelling waterproof rubber 11-2 is also applied to the inner peripheral surfaces of the structures 3-1 and 3-2, and the inner peripheral surface thereof is further covered with a protective steel plate 12-2. The following shows the case. As the protective steel plates 12-1 and 12-2, a band-shaped zinc steel plate having a thickness of about 3 mm and a width w of about 200 mm can be used.
[0014]
Further, in this embodiment, a case is shown in which a joint portion is filled with a joint material 6 such as, for example, an extrude to give a mutual reaction force between the adjacent structures 3-1 and 3-2. By filling the joint material 6 in this way and providing a structure in which adjacent structures 3-1 and 3-2 exert a mutual reaction force, the end faces of the structures 3-1 and 3-2 against a compressive load are formed. Can be prevented from being damaged.
As a construction method for covering the water-swelling water-stop rubbers 1-1 and 11-2 and the protective steel plates 12-1 and 12-2, a water-swelling water-stop rubber is provided on the hardened side of concrete, for example, at the end of the structure 3-1. 11-1 and 11-2 are adhered, and the outer periphery is further covered with protective steel plates 12-1 and 12-2. In this state, the water-swelling waterproof rubbers 11-1 and 11-2 to be applied to the structure where concrete is to be cast are held by the protective steel plates 12-1 and 12-2. The concrete of the structure 3-2 to be constructed next is cast on the surface of the water-swelling waterproof rubber 11-1 and 11-2 held by the and 12-2 to construct the structure 3-2.
[0015]
As described above, according to the present invention, since the waterproof rubbers 11-1 and 11-2 are not structured to be inserted into the concrete, the concrete placing operation can be performed easily, and the workability is smaller than that of the conventional case. Greatly improved.
FIG. 2 shows a modified embodiment of the present invention. In this embodiment, a case is shown in which the distribution muscle connecting the structures 3-1 and 3-2 is the distribution muscle 7-3 stored in the sheath tube 13. In other words, both ends of the distribution bar 7-3 are fixed to the concrete of the structures 3-1 and 3-2, and the distribution bar 7-3 is stored in the sheath tube 13 at the joint, and the distribution force is distributed inside the sheath tube 13. This shows a case where the muscle 7-3 has a structure capable of freely expanding and contracting.
[0016]
According to this structure, as described with reference to FIG. 4, when compressive load and tensile load are applied to the structures 3-1 and 3-2, the structures 3-1 and 3--3 are expanded and contracted by the distribution bars 7-3. An accident in which the end face of No. 2 is damaged can be prevented. As another structure, in this embodiment, there is shown a case in which an end face reinforcing bar 14 is provided to reinforce the strength of each end face of the structures 13-1 and 13-2. Since the structure of the other parts is the same as that of FIG. 1, further description is omitted here.
[0017]
【The invention's effect】
As described above, according to the present invention, the water-stopping performance is high, and even if the joints are greatly deformed, the water-swelling water-stopping rubbers 11-1 and 11-2 do not break. An excavated underground structure can be provided.
[Brief description of the drawings]
FIG. 1 is a sectional view for explaining an embodiment of the present invention.
FIG. 2 is a sectional view for explaining a modified embodiment of the present invention; FIG. 3 is a perspective view for explaining a general structure of an open-cut underground structure;
FIG. 4 is a cross-sectional view illustrating a structural joint used in a conventional open-cut underground structure.
FIG. 5 is a cross-sectional view for explaining a structure of an induced joint used in a conventional open-cut underground structure.
FIG. 6 is a perspective view for explaining the structure of a conventional water blocking plate.
[Explanation of symbols]
3-1, 3-2 Structure 6 Joint material 7-1, 7-2 Distributor 7-3 Distributor 11-1, 11-2 stored in the sheath tube 12-2 Protection steel plate

Claims (5)

In an open-cut underground structure buried underground and constructed with joints provided for each unit length to follow the displacement of the ground,
A water-swelling water-stopping rubber is applied in a band shape over substantially the same distance from the joints over the joints to serve as the joint to seal the outer periphery of the joints, and an outer peripheral surface of the water-swelling water-stopping rubber. An open-cut underground structure, characterized in that it is covered with a protective steel plate. 2. The open cut underground structure according to claim 1, wherein a water-swelling waterproof rubber is also applied to the inner periphery of the joint, and the inner peripheral surface of the water-swelling waterproof rubber is covered with a protective steel plate. Excavation underground structure. 3. The open cut underground structure according to claim 1, wherein the water-swelling waterproof rubber is made of non-vulcanized rubber. The open cut underground structure according to any one of claims 1 to 3, wherein the open cut underground structures connected at the joint portion are connected to each other by a force bar. The excavated underground structure according to any one of claims 1 to 4, wherein the excavated underground structures connected at the joints are connected to each other by a distribution muscle stored in a sheath tube. Underground structure.

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