JP3374327B2 - How to reinforce the shield tunnel - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for reinforcing a shield tunnel.

[0002]

2. Description of the Related Art A method of constructing a steel shield tunnel in the ground and then placing concrete inside to construct a steel shell concrete composite structure as a whole has been developed. If multiple concrete composite structures constructed in this way are connected in the ground, an extremely thick slab or wall surface can be built in the ground. If this slab or wall surface is used, a huge space with a side of several tens of meters can be formed in the ground.

In this case, a middle pillar is installed in the shield tunnel to be constructed first, and this middle pillar functions to resist the load of earth pressure and water pressure from the outer circumference of the tunnel. . However, there is a certain limit to the number that can be installed because it is necessary to secure a work space when constructing a shield tunnel. However, when it is tried to function as a shear-reinforced steel material after filling with concrete after that, the number is insufficient in number. For this reason, it is necessary to additionally install shear reinforcement steel inside the tunnel before placing concrete inside.

Conventionally, as shown in FIGS. 10 and 11, the method shown in FIGS. 10 and 11 has been used as a method for adding shear-reinforced steel. That is, two members having L-shaped processing a at one end and screw processing b at the other end are prepared. The tip of the L-shaped processing a is to the ceiling portion c of the shield tunnel and the through hole of the steel material in the floor portion d. ,
Insert each. A mechanical joint e is used to connect the threaded sides to provide shear reinforcement.

[0005]

The above-mentioned method of reinforcing a shield tunnel has the following problems. <A> A mechanical joint for joining upper and lower reinforcing bars is very expensive, and if used in a large amount, it becomes extremely uneconomical. <B> The L-shaped joint tends to come off due to the load from the inside. Therefore, there is a possibility that when the concrete is poured, it is pushed out by the pressure of the concrete and comes off. <C> The L-shaped joint is easily deformed when a tensile force is applied. Therefore, the tensile force that yields is deformed before it is applied, and the tensile force cannot be transmitted to the ceiling and the floor.

The present invention has been made to solve the above-mentioned conventional problems, and is a method for reinforcing a shield tunnel, which is inexpensive, can be easily installed, and can reliably transmit a tensile force. The purpose is to provide.

[0007]

In order to achieve the above object, the method for reinforcing a shield tunnel according to the present invention comprises:
In a method of arranging shear reinforcing bars between opposing surfaces inside a shield tunnel made of steel, the reinforcing bars are composed of a main material part and a mounting part at its tip, and the mounting part at one end is the main material part. Bend at a right angle with respect to the main material part, and then bend the tip at a right angle in a plane perpendicular to the main material part, and the mounting part at the other end is formed by forming a screw thread. It is characterized by a method of reinforcing a shield tunnel, which is carried out by engaging with the exposed openings of the vertical reinforcing ribs.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for reinforcing a shield tunnel according to the present invention will be described below with reference to the drawings.

<A> Reinforcing bar shape. The reinforcing bar 1 is a member for connecting the ceiling part and the floor part of the tunnel, or the wall surfaces on both sides, and is composed of a reinforcing bar. The reinforcing bar 1 is composed of a main material portion 11 at the center, a bending attachment portion 12 and a screw attachment portion 13 at the tip thereof.

<B> A mounting portion at one end. The bending attachment portion 12 at one end of the reinforcing bar 1 is formed by bending the reinforcing bar doubly into an L shape. That is, first, the main material portion 1
Bend at a right angle to 1. Next, the tip is bent at a right angle, and in particular, it is bent at a right angle in a plane orthogonal to the main material portion 11. In this way, the bending attachment portion 12 that is double-folded is completed.

<C> A mounting portion at the other end. The screw attachment portion 13 at the other end of the reinforcing bar 1 does not undergo a bending process in particular, and forms a screw thread on its outer periphery as a straight line. At the time of reinforcement, the nut 14 is tightened and fixed to this screw thread.

<D> Vertical reinforcing ribs. On the inner surface of the shield tunnel 2, vertical reinforcing ribs 3 made of an L-shaped steel material are exposed on the ceiling, floor, and wall surfaces.
"Vertical" means parallel to the traveling direction of the tunnel 2.
A large number of reinforcing ribs 3 oriented in the traveling direction are arranged inside the skin plate, and a center pillar 4 is arranged in the middle. Through holes 31 are opened at regular intervals on one side of the reinforcing rib 3, for example, an L-shaped rising surface of the reinforcing rib 3 on the ceiling. The diameter of the through hole 31 is set to be slightly larger than the diameter of the reinforcing bar 1 described above. On the other hand, a U-shaped groove 32 is opened on the side of the L-shaped plane in the reinforcing rib 3 on the floor facing the ceiling. The width of this opening is also made slightly larger than the diameter of the reinforcing bar 1.

The above is the combination of the through hole 31 and the U-shaped groove 32, but it is also possible to adopt a combination in which the through holes 31 and 33 are opened in the reinforcing ribs 3 on both sides as shown in FIG. In that case, the through hole 31 on the ceiling side is opened on the rising surface of the L-shaped reinforcing rib 3, and the through hole 33 on the floor side is opened on the flat side of the reinforcing rib.

[0014]

[Attachment Method] Next, a method of attaching the steel reinforcing bar 1 will be described.

<A> A combination of the through hole 31 and the U-shaped groove 32. (FIG. 5) First, the mounting portion on one side of the main member that is formed by bending is inserted into the through hole 31 of the vertical reinforcing rib 3 exposed on one surface of the shield tunnel 2, for example, the inner surface of the ceiling surface. Then, the bent portion in the plane orthogonal to the main member is inserted into the through hole 31. After that, the main material portion 11 is rotated. Then, the portion orthogonal to the main member is inserted into the through hole 31 and the engagement is completed. Since the other end of the main member is formed with a screw thread, its mounting portion is engaged with the U-shaped groove 32 of the vertical reinforcing rib 3 exposed on the opposing surface, for example, the inner surface of the floor surface.
Since the U-shaped groove 32 is open to one side, insertion from the side surface is easy. After insertion, screw the nut 14
The connection can be completed by screwing in. Thus, the tensile force acting on the reinforcing bar can be effectively transmitted to the surrounding structures via the vertical reinforcing ribs 3.

<B> A combination of the through hole 31 and the through hole 33. (FIG. 6) When the through holes 31, 33 are opened in the opposing vertical reinforcing ribs 3 on both sides, first, the mounting portion on the side where the screw thread is formed is attached to one side (in the embodiment of FIG. Side) The vertical reinforcing rib 3 is inserted into the through hole 33. At that time, the nut 14 is not yet fastened, but left in a free state. In that state,
The mounting part on the side formed by bending is the other side (ceiling side)
The vertical reinforcing rib 3 is inserted into the through hole 31. Then, by rotating the main material portion 11, the upper and lower sides of the reinforcing bar 1 can be engaged. After that, if the nut 14 is screwed into the mounting portion on the side where the threads are formed, the mounting is completed.

<C> Tilt arrangement. (FIGS. 7-9) It is also possible to attach the main member with an inclination. In that case, after inserting the mounting portion on the side formed by bending into the through hole 31 of the vertical reinforcing rib 3, the main material portion 11 is rotated and engaged, and the mounting portion on the side where the screw thread is formed is
It engages with the U-shaped groove 32 of the vertical reinforcing rib 3 on the opposite side. After that, when the nut 14 is screwed in, the nut 14 is screwed in with an inclined spacer 15 formed according to the inclination angle of the main material portion 11 interposed. This inclination angle is arranged in a direction orthogonal to the direction of the crack when it is highly likely that diagonal cracks will occur in the concrete due to shearing force.

[0018]

As described above, the reinforcing method of the shield tunnel 2 of the present invention arranges the reinforcing bar 1 as the shear reinforcement of the steel-shell concrete composite structure, thus forming a shear truss mechanism and effectively functioning. Can be made.
Therefore, the following effects can be obtained. <B> Since the shear reinforcing bar 1 is a lightweight member, it is not necessary to use a special device or machine, it can be easily set manually and can be constructed in a short time and at low cost. <B> Since the shape of the mounting portions at both ends of the shear reinforcing bar 1 is simple, the manufacturing and processing costs thereof are also low. <C> In many cases, the shield tunnel 2 is deformed by the earth pressure of the surroundings, and the size of the inner space is not accurate. However, according to the method of the present invention, since one end of the reinforcing bar 1 is a combination of the bolt and the nut 14, the size adjustment is extremely simple. <D> The attachment portion may be deformed when a tensile force enough to yield the shear reinforcing bar 1 is applied. However, the reinforcing bar 1 of the present invention is difficult to be deformed because its mounting portion is double processed, and the tensile force of the shear reinforcing bar is applied to the vertical reinforcing ribs 3.
Can be reliably transmitted. <E> Although diagonal cracks may occur in concrete due to shearing, the method of the present invention allows reinforcement in a direction orthogonal to the diagonal cracks, and the most effective shear reinforcement can be performed. <F> When filling the inside of a segment with concrete, it is difficult to work if many reinforcing bars are standing in a forest. However, according to the method of the present invention, the reinforcing bar 1
It is possible to penetrate only the upper end of the through hole 31 into the through hole 31 and lift the lower end to be temporarily fixed parallel to the ceiling. Therefore, the work does not become an obstacle and the work efficiency does not decrease. <G> Not only in the case of arranging the reinforcing bar 1 between the ceiling part and the floor part, but in the case of the vertical tunnel 2, the reinforcing bar 1 is arranged between the wall faces to expect the same effect. can do.

[Brief description of drawings]

FIG. 1 is an explanatory view of an example of the structure of a steel shield tunnel.

[Fig. 2] Reinforcing bar 1 used to reinforce the shield tunnel
Illustration of an example

FIG. 3 is an explanatory diagram of a ceiling side reinforcing rib 3 of a shield tunnel.

FIG. 4 is an explanatory view of a floor side reinforcing rib 3 of the shield tunnel.

FIG. 5 is an explanatory view of a method for attaching reinforcing bars.

FIG. 6 is an explanatory diagram of another method of attaching reinforcing bars.

[Fig. 7] An explanatory view of a mounting state of diagonal reinforcing bars

FIG. 8 is an explanatory view of a mounting state of diagonal reinforcing bars.

FIG. 9 is an explanatory view of a mounting state of diagonal reinforcing bars.

FIG. 10 is an explanatory diagram of a conventional reinforcing method.

FIG. 11 is an explanatory diagram of a conventional reinforcing method.

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) E21D 13/00-13/04 E21D 11/10 E21D 11/14

Claims (4)

(57) [Claims] Claim: What is claimed is: 1. A method of arranging shear reinforcing bars between opposing surfaces inside a shield tunnel made of steel, wherein the reinforcing bars are composed of a main material portion and a mounting portion at its tip, and a mounting portion at one end. Is bent at a right angle to the main material portion, and the tip is further bent at a right angle in a plane orthogonal to the main material portion, and the mounting portion at the other end is formed by forming a screw thread. A method of reinforcing a shield tunnel that engages with the openings of the vertical reinforcing ribs exposed on the inner surface of the shield tunnel. 2. A method of arranging shear reinforcing bars between opposing surfaces inside a shield tunnel made of steel, wherein the reinforcing bars are composed of a main material portion and a mounting portion at its tip, and a mounting portion at one end. Is bent at a right angle to the main material portion, and the tip is bent at a right angle in a plane orthogonal to the main material portion, and the mounting portion at the other end is formed by forming a screw thread and is formed by bending. The mounting part on the side is inserted into the through hole of the vertical reinforcing rib exposed on the inner surface of the shield tunnel, and then the main material part is rotated to engage, and the mounting part on the side where the screw thread is formed is the inner surface of the shield tunnel. A method for reinforcing shield tunnels, which involves screwing a nut into the U-shaped groove of the vertical reinforcing rib exposed at the bottom. 3. A method of arranging a shear reinforcing bar between opposing surfaces inside a shield tunnel made of steel, wherein the reinforcing bar is composed of a main material portion and a mounting portion at its tip, and a mounting portion at one end. Is bent at a right angle to the main material, and the tip is bent at a right angle in a plane orthogonal to the main material, and the mounting portion at the other end is formed by forming a screw thread to form a screw thread. The mounting part on the side that was inserted was inserted into the through hole of the vertical reinforcing rib exposed on the inner surface of the shield tunnel, and the mounting part on the side that was bent was inserted into the through hole of the vertical reinforcing rib exposed on the inner surface of the shield tunnel. Later, the main tunnel is rotated and engaged, and then the nut is screwed into the mounting part on the side where the threads are formed. 4. A method of arranging shear reinforcing bars between opposing surfaces inside a shield tunnel made of steel, wherein the reinforcing bars are composed of a main material portion and a mounting portion at its tip, and a mounting portion at one end. Is bent at a right angle to the main material portion, and the tip is bent at a right angle in a plane orthogonal to the main material portion, and the mounting portion at the other end is formed by forming a screw thread and is formed by bending. The mounting part on the side is inserted into the through hole of the vertical reinforcing rib exposed on the inner surface of the shield tunnel, and then the main material part is rotated to engage, and the mounting part on the side where the screw thread is formed is the inner surface of the shield tunnel. A method of reinforcing a shield tunnel in which a nut is screwed in through a slope spacer formed according to the inclination angle of the main material portion after engaging with the U-shaped groove of the vertical reinforcing rib exposed at the.