JP4580361B2 - How to prevent falling pieces of structure - Google Patents

Description

  The present invention relates to a method for preventing fall of a peeled piece from a structure such as a tunnel or a bridge, and more particularly to a method for preventing the fall of a peeled piece of a structure to prevent an accident caused by a sudden drop of the peeled piece. .

  Among the methods that have been used in the past as a method for preventing the peeling of structures such as concrete, the “method of fixing metal nets, expanded metal, etc. with anchor bolts” is not only smoothing the mounting surface but also according to the laying surface shape. However, if there is an existing object such as a cable in the laying section, it will be complicated by fine processing each time, so the construction cost will not only be expensive, but also near the repair site There is also the risk that the reinforcing material will deteriorate and the reinforcing effect will be reduced if water is spilled out, and that electrical accidents will occur due to the use of metal. In addition, the “method of spraying and fixing carbon or vinylon fiber etc. with polymer cement mortar” is widely adopted, but the construction cost is expensive due to measures such as cleaning and smoothing the mounting surface, so the repair target is It must be limited. Furthermore, when a spring water path is created in the structure, the reinforcing layer such as mortar is easily peeled off, leaving a risk of peeling off.

  As a means for solving these problems, Patent Document 1 proposes “a method of fixing a grid-like fall prevention material, which is a mesh fabric or net made of a glass fiber bundle or the like, with an anchor bolt” or the like. However, 1) glass fibers have a weak point that they are liable to cause shear failure, so that they cannot be woven. When a net is used, it is difficult to ensure the fixing strength at the intersection, and the problem of misalignment easily occurs. ) There is a problem that the shape of the net of the net is elongated and deforms easily under load, and the installed net itself droops greatly. The drooping of the net is affected by changes in the wind pressure due to the train wind of the train passing through the tunnel, and there is concern about the long-term reliability of fatigue deterioration, and also makes it difficult to visually check the structure surface. .

JP 2004-293150 A

  Under such circumstances, the object of the present invention is a lattice-like fall prevention material laid on the inner wall of a structure such as a tunnel, and it is easy to visually recognize the structure surface because it does not hang down like a conventional net, and It is providing the peeling piece fall prevention method using the grid | lattice-like fall prevention material which is excellent in workability.

  As a result of intensive studies, the inventors of the present invention have used a rigid fiber bundle that has been given rigidity in the lateral direction, a flexible fiber bundle that has not been given rigidity in the vertical direction, and each intersection of both fiber bundles. The present invention has been completed by finding that the above object can be achieved by using a grid-like fall prevention material, which is a saddle-like long net to which is fixed.

That is, the present invention
(1) A method for preventing fall of a peeled piece of a structure formed by fixing a lattice-like fall prevention material on the structure surface, wherein the lattice-like fall prevention material uses a rigid fiber bundle imparted with rigidity in the lateral direction, A method for preventing fall of a peeled piece of a structure, which is a saddle-like long net to which each intersection of both fiber bundles is fixed using a flexible fiber bundle not given rigidity in the longitudinal direction;
(2) The method for preventing fall of the peeled piece of the structure according to (1) above, wherein the fiber bundle constituting the lattice-like fall prevention material is made of non-flammable or self-extinguishing and non-conductive fibers;
(3) The fiber bundle constituting the lattice-shaped fall prevention material is at least one fiber bundle selected from the group consisting of a glass fiber bundle, a carbon fiber bundle, an aramid fiber bundle, a vinylon fiber bundle, a nylon fiber bundle, and a super fiber bundle. (1) or (2) a method for preventing a peeling piece of the structure from falling off;
(4) In the structure according to any one of (1) to (3), the rigidity of the lateral fiber bundle and the fixing of the intersection of both fiber bundles are due to impregnation with a flame-retardant or self-extinguishing resin. How to prevent the peeling piece from falling;
(5) A method of preventing the peeling piece of the structure according to any one of the above (1) to (4) from falling, in which the lattice spacing of the lattice-shaped fall prevention material is 10 to 50 mm in both vertical and horizontal directions;
(6) A method for preventing fall of the peeled piece of the structure according to any one of (1) to (5), wherein a lattice-shaped fall prevention material is fixed to the surface of the structure with an anchor;
I will provide a.

  The present invention relates to a grid-like fall prevention material using a rigid fiber bundle imparted with rigidity in the lateral direction, a flexible fiber bundle not imparted with rigidity in the longitudinal direction, and each intersection of both fiber bundles being fixed. By using this, it is possible to prevent accidental dropping of peeled pieces of structures such as concrete and to prevent falling off like conventional nets. is there. In addition, since it is a bowl-shaped long net, it is easier to wind in a roll shape than conventional nets, and it is easy to lay the inner wall of a structure such as a tunnel, and there are few fixed points with anchor bolts or the like. It is excellent in workability.

The method for preventing fall of the peeled piece of the structure of the present invention uses a rigid fiber bundle imparted with rigidity in the transverse direction, a flexible fiber bundle not imparted with rigidity in the longitudinal direction, and each of the two fiber bundles. It is characterized by using a grid-like fall prevention material to which the intersection is fixed.
That is, the lattice-like fall prevention material (hereinafter sometimes referred to as “net”) used in the present invention is a lattice of warp and weft made of fiber bundles of non-flammable or self-extinguishing and non-conductive long fibers. It is manufactured as a long net, and the entire width of the weft and the intersection of the warp and weft are solidified with a flame-retardant or self-extinguishing resin.

  In the present invention, the fiber used for the fiber bundle of non-flammable or self-extinguishing and non-conductive long fibers includes glass fiber, carbon fiber, aramid fiber, vinylon fiber, nylon fiber, super fiber (PBO fiber, PPS fiber) , Polyimide fiber) and the like, and glass fiber is preferably used from the viewpoint of cost.

  In addition, as the flame retardant or self-extinguishing resin, a flame retardant resin mainly composed of polyvinyl chloride or the like can be used. These flame retardant or self-extinguishing resins are used in a solution dissolved in a solvent, if necessary.

The weft of the lattice fall prevention material of the present invention is a rigid fiber bundle in which a large number of long fiber bundles are impregnated with resin to give rigidity, and the cross-sectional shape is not particularly limited, and may be a circle, an ellipse, a quadrangle, etc. The shape can take a shape, and the size is preferably about 0.5 to 4 mm in diameter when circular, and about 1.5 mm × 0.5 mm to 3.8 mm × 3.8 mm when square. In addition, the length of the weft (effective width of the hook-shaped net) is preferably about 1000 mm or about 2000 mm from the viewpoint of workability when installing the fall prevention material.
The warp is a flexible fiber bundle that has not been given rigidity, and its thickness is not particularly limited, as long as it has a strength that constitutes a lattice-like fall prevention material.

  The distance between the vertical and lateral eyes of the lattice-shaped fall prevention material is preferably about 15 to 25 mm from the standpoint of preventing the peeling pieces from falling and the visibility of the structure surface.

Although the manufacturing method of the lattice-shaped fall prevention material of this invention is not specifically limited, For example, it can manufacture as follows.
In the weft production process, a large number of long fiber bundles are impregnated into a resin bath under tension, dried and solidified, and cut into a predetermined length of the weft. In the net manufacturing process, an adhesive is applied to the intersection of the weft yarns with the warp yarns, and the weft yarns and warp yarns arranged so as to have a predetermined mesh interval are adhered to each other, thereby producing a hook-like long net. .
Alternatively, a net is woven using wefts pre-impregnated and dried with resin and warp yarns pre-impregnated with a small amount of resin or pre-impregnated with resin, and the entire net is impregnated in the resin impregnation tank. Then, by passing through a compression roll or the like and then drying, it is possible to produce a long net having a hook shape in which the weft and the warp are fixed (the weft is more rigid than the warp).

In the present invention, the lattice-like fall prevention material is fixed to the surface of a structure such as a tunnel with an anchor. As the anchor, either a metal anchor or an adhesive anchor may be used, or both may be mixed. . The procedure for fixing the lattice-shaped fall prevention material to the surface of the structure is, for example, as follows.
Roll-out nets are unrolled from the laying auxiliary device along the curved surface of the tunnel, and after checking the close contact with the wall surface, the net end is aligned with the net fixed end that has been determined in advance below the tunnel, either directly or for bonding After the resin is applied, anchors are placed so that the upper and lower ends of the net are fixed, the net is temporarily fixed, and the stainless steel is used in the longitudinal direction of the net (to strengthen the connection between the ends of the net and to connect the anchors). The connecting plate is pressed along the curved surface from the lower end portion to the upper end portion, and the anchors are sequentially fixed to the long holes formed in the stainless steel connecting plate at an equal pitch.
The anchor bolt or the anchor pin is preferably placed at a substantially central position of the stainless connecting plate oblong hole at an interval of 500 to 700 mm, and the washer has a size of 40 to 60 mm according to the size of the grid of the net and the stainless connecting plate. Is preferred.

<Manufacture of lattice fall prevention material>
In the weft production process, each long fiber bundle is set in a tensioned state and then impregnated with a vinyl chloride resin. After that, 20 mm pitch (net mesh) is applied to one surface of the weft (cross section 1.7 mm × 3.5 mm). A semi-elliptical depression (depth of about 0.8 mm) is added to each interval), and then dried and cured, and trimmed so that the effective width is 1000 mm for the weft.

In the next step, the wefts in which the adhesive resin is applied to the surface with the semicircular depression sandwich the warp yarns from both the upper and lower sides in one set. The position where the warp yarn is sandwiched is an elliptical recess formed by combining a pair of up and down semi-elliptical recesses of the weft yarn. All warp yarns on the production line are regularly manufactured at an equal pitch of 20 mm. Will be.
Due to the depressions forming the intersections, a sufficient amount of resin is held so that the warp yarns intersect with the weft yarns at an accurate pitch and are securely bonded at the intersections. Further, since the oval depression does not compress the warp, even a glass fiber that is weak against bending and twisting that occurs when the peeling piece is dropped can secure the required strength without being broken.
Thus, a bowl-shaped long net is manufactured.

<Construction of grid-like fall prevention material on the inner wall of railway tunnel>
The net is unwound while rotating the net horizontal holding tool of the net laying auxiliary device, and pulled down along the curved surface of the tunnel while sliding on the arc-shaped net holding tool. After the net reaches the fixed bottom end of the tunnel curved surface, push up the entire net laying auxiliary device to make sure that the net is in close contact with the correct mounting position of the tunnel curved surface. After the stainless steel connecting plate is set so as to be perfectly aligned with the center line in the longitudinal direction of the net, the top anchor is loosely temporarily fixed, and an adhesive resin is applied to the portion of the net where the back surface of the stainless connecting plate hits. After the application is completed, the temporary anchor is permanently tightened and fixed.
Next, the bottom end of the stainless steel connecting plate is pushed upward, and after confirming that the tunnel curved surface, the net, and the stainless steel connecting plate are in close contact with each other, the anchor at the bottom end is driven and fixed. Drill the holes of all remaining anchors for fixing the stainless steel connecting plate, and fix the anchors.
After completing the above-mentioned operation of fixing the stainless steel connecting plate for fixing the center line in the longitudinal direction of the net, attach and fix the stainless steel connecting plate to the lap portion with the already installed net in the same procedure as above. .

Claims (6)

  A method for preventing fall of a peeling piece of a structure in which a lattice-shaped fall prevention material is fixed to the surface of the structure, wherein the lattice-like fall prevention material uses a rigid fiber bundle having rigidity in the lateral direction, and in the longitudinal direction. A method for preventing fall of a peeled piece of a structure, which is a saddle-like long net to which each intersection of both fiber bundles is fixed using a flexible fiber bundle not imparted with rigidity.   The method for preventing fall of a peeled piece of a structure according to claim 1, wherein the fiber bundle constituting the lattice-like fall prevention material is made of non-flammable or self-extinguishing and non-conductive fibers.   2. The fiber bundle constituting the lattice-shaped fall prevention material is at least one fiber bundle selected from the group consisting of a glass fiber bundle, a carbon fiber bundle, an aramid fiber bundle, a vinylon fiber bundle, a nylon fiber bundle, and a super fiber bundle. Or the fall prevention method of the peeling piece of the structure of 2.   The fall of the exfoliation piece of the structure according to any one of claims 1 to 3, wherein the rigidity of the transverse fiber bundle and the fixation of the intersection of both fiber bundles are due to impregnation with a flame-retardant or self-extinguishing resin. Prevention method.   The method for preventing fall of the peeled piece of the structure according to any one of claims 1 to 4, wherein both the vertical and horizontal eye intervals of the lattice-shaped fall prevention material are 10 to 50 mm.   The method for preventing fall of the peeled piece of a structure according to any one of claims 1 to 5, wherein a lattice-like fall prevention material is fixed to the surface of the structure with an anchor.