JP4097028B2 - How to repair polygonal column structures - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a restoration of strength reduction due to deterioration of a polygonal column structure such as columns, beams, girders, and piers constructed of concrete, steel, etc., reinforcement, prevention of progression of deterioration, repair of a polygonal column structure such as seismic reinforcement, It relates to repair methods for polygonal column structures such as reinforcement and function improvement work.
[0002]
[Prior art]
Concrete structures and steel structures deteriorate over time due to various material and structural factors, causing cracks and corroding internal reinforcing bars, and cross-sectional defects due to corrosion, resulting in reduced structural strength. Therefore, it is necessary to make repairs and reinforcements as necessary.
Conventionally, in the repair method of polygonal column structures such as columns a and beams, a method of installing a precast concrete plate b, a method of installing a steel plate, a method of winding a chemical fiber sheet such as carbon fiber, a method of spraying mortar, Methods of applying chemical materials have been implemented.
In this method, in the method of installing the precast concrete plate b or the steel plate on the outer periphery of the pillar a or the like, the precast concrete plate b or the like produced or processed in advance at a factory or the like is brought into the site and installed.
Usually, the precast concrete slab b is manufactured with a prescribed dimension having an L-shaped cross section. This is a measure for suppressing the occurrence of a weak portion or a reinforcing portion having a large cross section at the corner portion because the joint portion is butt-joined when the precast concrete plate b or the like is installed, and the joint portion tends to be a weak portion.
And between the precast concrete plates b arrange | positioned for every corner | angular part of the pillar a is connected with the connection panel c for a connection.
[0003]
[Problems to be solved by the invention]
As described above, the conventional method for repairing a polygonal column structure has the following problems.
<A> The large precast concrete slab b is often manufactured with specified dimensions and angles, and is difficult to manufacture in accordance with the shape of the structure. For example, when the outer periphery is covered with concrete in accordance with the shape of the pillar a, the placement and formwork are manufactured on site without using the precast concrete plate b, and the cast-in-place concrete is placed. However, there are some sites where working hours can only be secured for several hours a day, such as railway construction, and the construction period is very long at such sites. In addition, when the work space is limited, it may not be possible to construct with this method.
<B> When the precast concrete slab b is used as a structural member, if a member with a very acute angle is produced, the structural yield strength is lowered, so that a flat plate member or an L-shaped member having a right angle or an obtuse angle is formed. On the other hand, the pillar a that requires refurbishment has been distorted due to external forces such as long-term use and earthquakes, corners were originally manufactured at angles other than right angles, and there were construction errors, Often does not match the shape of the precast concrete plate b. However, as described above, since it is difficult to manufacture the precast concrete slab b in accordance with the shape of the pillar a etc. from the viewpoint of production cost and process, the precast concrete slab b having a prescribed size is used. Become. It is difficult to install the precast concrete slab b of such a prescribed size in conformity with the corners of the non-standard shape. There is a risk of eroding structures (see FIG. 4). For this reason, it takes time to install the precast concrete slab b at the corners, resulting in poor work efficiency.
[0004]
OBJECT OF THE INVENTION
The present invention has been made to solve the above-described conventional problems, and an object thereof is to provide a method for repairing a polygonal column structure having excellent workability.
Moreover, it aims at providing the repair method of the polygonal column structure which can ensure the quality which matched the objective of the repair of the polygonal column structure easily.
Furthermore, it aims at providing the repair method of the polygonal column structure which can maintain the outer periphery of the repaired polygonal column structure in a plane, without a junction part becoming a weak part.
The present invention achieves at least one of these objects.
[0005]
[Means for Solving the Problems]
In order to achieve the above-described object, the polygonal column structure repair method of the present invention includes two polygonal column structure repair methods in which the outer periphery of the polygonal column structure having a plurality of corners is covered with a panel. A flat panel in which at least one of the end portions of the inner panel protrudes from the outer panel and the reinforcing layer is exposed is formed on the flat portion of the polygonal column structure. respectively arranged with a predetermined interval in the front, between the outer panel of the flat panel disposed across the corner, corner panel to suit and the angle of the corner has a reinforcing layer on the inside Is inserted, and a bonding material is filled between the polygonal column structure and the flat panel. Here, the polygonal column structure includes a quadrangular columnar or hexagonal columnar structure such as a column, a beam, a girder, a pier, a tank, or a chimney. In addition, the corner of the polygonal column structure means a portion where the extended surfaces of the plane portion intersect. Usually, the two corners forming the chamfered portion applied at the corner of the structure are one corner. Shall be included. For example, although a normal column is formed in a quadrangular column shape, if chamfered portions are provided in each of the four corners, it can be said that it is an octagonal column, but there are four corner portions.
Moreover, in the repair method of said polygonal column structure, it is preferable to join the edge parts of an inner side panel between the said panels for plane arrange | positioned on both sides of the said corner | angular part.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention relates to a method for repairing a polygonal column structure 1, and the polygonal column structure 1 includes a columnar structure such as a column 1 a, a beam 1 b, a girder, a bridge pier, a tank or a chimney, and a hexagonal columnar structure. It is. In addition, even if it is a substantially quadrangular prism-shaped structure, it may become an octagonal column correctly by chamfering etc. (refer FIG. 1), but such a shape is demonstrated as a quadrangular column.
[0007]
<A> Structural Panel The structural panel 2 is composed of a basic panel, a reinforcing layer 213, and an adhesive. The structural panel 2 is formed by sandwiching a reinforcing layer 213 between two basic panels and integrating them with an adhesive.
Different materials can be used for the basic panels sandwiching the reinforcing layer 213. The basic panel can also be formed by overlapping a plurality of panels.
The basic panel is a plate material used to protect the reinforcing layer 213 and increase the rigidity of the structural panel 2.
As the basic panel, high strength concrete, fiber reinforced concrete, flexible board, polyolefin fiber reinforced panel, or the like can be used.
If a cement-based material (such as concrete or mortar) such as high-strength concrete is used, the basic panel can be easily formed into an arbitrary shape. For this reason, even if the corner | angular part of the polygonal-pillar structure 1 is what kind of shape, the suitable basic panel can be shape | molded easily. For example, a high-strength, high-fluidity cement material in which water and premix cement and fine aggregate, polyolefin fiber, high-performance water reducing agent, etc. are mixed can be used.
[0008]
The flexible board has cement and organic fibers (pulp) as main components, and after kneading them, it is formed into a roll and dehydrated and pressed. As this high-strength flexible board, a well-known product can be used, and an easily available product is a standard product having a thickness of 3 mm to 6 mm.
The flexible board can be easily manufactured in the factory, the product quality is stable, the bending strength is as large as 30 (N / mm ² ) or more, the surface does not crack, and it has non-flammability. There is an advantage from the viewpoint.
Furthermore, there are also advantages from the viewpoint of workability such as easy processing and molding into a desired shape and ease of workability and transportation because the specific gravity is as light as 1.6 to 1.8.
[0009]
The polyolefin-based fiber reinforced panel is a panel formed by mixing polyolefin-based reinforcing fibers, cement, and organic fibers. Here, pulp or the like is used as the organic fiber.
The polyolefin-based fiber reinforced panel is a product having a thickness of about 3 mm to 15 mm, and is very thin and light compared to a normal precast concrete plate. For this reason, the size per panel can be increased and the workability is excellent. Further, forming such as bending can be easily performed.
[0010]
The polyolefin-based reinforcing fiber is a fiber material made of a polyolefin-based material such as polypropylene, polyethylene, or polybutene.
Among these, polyolefin-based reinforcing fibers using polypropylene as a raw material are particularly suitable.
The polyolefin-based reinforcing fiber is formed to a length of, for example, about 6 to 30 mm and used as a short fiber.
In addition, the surface of the polyolefin-based reinforcing fiber is subjected to a special embossing process so as to be uneven. As a result, it is difficult for the cement to come off and the bending toughness (stickiness) of the panel is improved.
Further, the surface shape of the polyolefin-based reinforcing fiber is subjected to a hydrophilic treatment to increase the interfacial adhesive force with the cement matrix. Polypropylene is hydrophobic so that its surface does not blend with water when it is untreated, so that the strength and toughness of the panel can be improved by applying a hydrophilic treatment.
The tensile strength of the polyolefin-based reinforcing fiber is 400 to 480 (N / mm ² ), and the strength characteristics and various physical properties of the panel can be improved.
Polyolefin-based reinforcing fibers made of polypropylene as a raw material have excellent alkali resistance, do not rust, and do not generate nitrogen, sulfur or chlorine-based harmful gases during combustion.
Furthermore, since the specific gravity is as light as 0.91, the panel can be reduced in weight.
[0011]
<B> Flat Panel The flat panel 21 is a panel constituting the structural panel 2. The structural panel 2 is constructed by joining a plurality of flat panels 21.
The flat panel 21 includes two basic panels and a reinforcing layer 213 sandwiched between them. The basic panel disposed on the polygonal column structure 1 side is referred to as an inner panel 211, and the basic panel disposed outside is referred to as an outer panel 212.
At least one end of the inner panel 211 protrudes from the outer panel 212. FIG. 1 and FIG. 2 show an embodiment in which both ends of the inner panel 211 protrude from the outer panel 212. When constructing the structural panel 2, the adjacent inner panels 211 are joined together. The joining between the inner panels 211 may be via a known joint joint.
Further, the joining of the inner panels 211 in the vicinity of the corners of the polygonal column structure 1 is a cross joining. For example, as shown in FIG. 1, the cross-joining is a joining in which the corners of the inner panel 211 are abutted against each other. As shown in FIG. 2, one inner panel 211 covers the end surface of the other inner panel 211. It may be.
[0012]
<C> Corner panel 22 The basic panel installed in the gap between the outer panels 212 and 212 generated when the planar panels 21 and 21 are joined at the corner of the polygonal column structure 1 is the corner panel 22. It is. A reinforcing layer 213 may be attached to the inside of the corner panel 22 as necessary.
The corner panel 22 is formed in accordance with the angle of the corner of the polygonal column structure 1, that is, the angle at which the extended surfaces of the plane portions intersect. Since the basic panel processed into the corner panel 22 as described above can be easily bent, the corner panel 22 may be processed according to the angle of the corner of the polygonal column structure 1. The corner panel 22 is a dedicated panel manufactured for placement at the corner, and is small in size and can be easily placed at the corner.
According to this connection method, the corner panel 22 and the planar panel 21 are integrated to form the structural panel 2. Moreover, since the junction part between the plane panels 21 and 21 is covered with the corner | angular part panel 22, the structural panel 2 can be firmly integrated and constructed | assembled.
In addition, when the junction part between the panels 21 and 21 for planes generate | occur | produces in a plane part, a flat basic panel should be used as a connection panel, and it should just fit in the clearance gap between the outer side panels 212 and 212. FIG.
[0013]
<D> Reinforcing layer The reinforcing layer 213 is a sheet-like or plate-like material arranged to increase the strength of the structural panel 2.
For the reinforcing layer 213, for example, a carbon fiber sheet, an aramid fiber sheet, a polyethylene fiber sheet, a polypropylene fiber sheet, a glass fiber sheet, a vinylon fiber sheet, or the like can be used. Here, various fiber sheets can use a well-known single orientation sheet, what laminated | stacked the single orientation sheet alternately like a plywood, a cross-shaped thing, etc. can be used.
When various fiber sheets are used as the reinforcing layer 213, it is necessary to use a material or a weaving method in which at least the adhesive penetrates in order to impregnate the adhesive. Here, the impregnation means that a liquid substance (adhesive) is infiltrated into the voids in order to modify the porous object (fiber sheet). The impregnation with the adhesive may be performed in advance before the flat panel 21 or the corner panel 22 is manufactured, or may be performed during the manufacturing.
[0014]
Here, the carbon fiber sheet is lightweight with a specific gravity of 1.7 to 1.8, and has a property that does not rust, and in the fiber direction, it is 5000 to 6000 (N / mm ^2), which is about 5 to 6 times the reinforcing bar. ) Has a large tensile strength.
Therefore, a structural strength equal to or higher than that of reinforced concrete can be obtained with a thin film by disposing a carbon fiber sheet between high-strength basic panels.
Note that the reinforcing layer 213 can be formed by stacking a plurality of the above-described sheets.
[0015]
<E> Adhesive The adhesive may be any material as long as it can be integrally formed by firmly joining the basic panel and the reinforcing layer 213 and the reinforcing layer 213 and the corner panel 22. Although good, an epoxy resin is preferred from the viewpoint of adhesive strength and workability.
Other adhesives include vinyl acetate resin, EVA (ethylene vinyl acetate copolymer resin), acrylic resin, and other rubber adhesives, and chloroprene rubber, styrene / butadiene rubber, and other rubber adhesives. It is also possible to use an adhesive or a water / air-hard adhesive such as cement or gypsum.
[0016]
<F> Joining material The joining material 3 is a material that is interposed between the structural panel 2 and the polygonal column structure 1 to integrate them. Any material can be used as long as it can be integrated, but high strength non-shrink mortar is preferable from the viewpoint of adhesive strength and workability.
Other bonding materials 3 include epoxy resin, EVA (ethylene vinyl acetate copolymer resin), polymer resin, vinyl acetate resin, silicone, acrylic resin, and other adhesives such as chloroprene. It is also possible to use rubber-based adhesives such as rubber-based or styrene / butadiene rubber-based or water / air-based adhesives such as cement-based or gypsum-based.
[0017]
[Example 1]
Hereinafter, an embodiment of a method for repairing the columnar polygonal column structure 1a will be described with reference to FIGS.
[0018]
<A> Installation of flat panel First, the deteriorated portion of the surface of the polygonal column structure 1a is removed as necessary.
And the panel 21 for a plane is each arrange | positioned to the plane part of the polygonal-pillar structure 1a. For example, when repairing the square columnar pillar structure 1a, the flat panel 21 is disposed on each of the four plane portions serving as the side portions (see FIGS. 1 and 2).
The flat panel 21 is arranged at a predetermined interval from the polygonal column structure 1a. For example, it is preferable to attach a spacing member 4 made of angle steel, channel steel, or the like to the inner surface of the inner panel 211 so that a predetermined spacing is maintained when it is disposed in front of the flat surface (see FIG. 2). ).
[0019]
<B> Installation of corner panel When the flat panel 21 is installed on each plane portion of the polygonal column structure 1a, a junction between the plane panels 21 and 21 is formed at the corner of the polygonal column structure 1a. The corner panel 22 is disposed so as to cover the joint.
The corner panel 22 is disposed so as to be fitted between the outer panels 212 of the planar panels 21 and 21, and the planar panel 21, the adhesive applied to the corner panel 22 and the reinforcing layer 213, anchor bolts, or the like. 21 is fixed.
Since the corner panel 22 is a relatively small dedicated member manufactured for the corner, it is easy to handle and can be easily disposed at the corner. Moreover, since it shape | molds according to the angle of the corner | angular part of the polygonal-pillar structure 1a, it can attach in a short time.
[0020]
<C> Filling the bonding material Finally, the bonding material 3 is filled between the structural panel 2 including the flat panel 21 and the corner panel 21 and the polygonal column structure 1a (see FIG. 1).
A protrusion such as a bevel can be attached to the surface of the inner panel 211 on the side of the polygonal column structure 1a as necessary to increase the adhesion.
[0021]
[Example 2]
Next, an embodiment of a method for repairing the beam-shaped polygonal column structure 1b will be described with reference to FIG.
The repair method is basically the same whether the columnar polygonal column structure 1a or the beam-shaped polygonal column structure 1b described in the first embodiment.
However, the beam-like polygonal column structure 1b is often used as a girder, and the structure panel 2 may not be arranged so as to surround the outer periphery of the polygonal column structure 1b. In such a case, the surface exposed as the polygonal column structure 1b may be covered with the structural panel 2 constituted by the flat panel 21 and the corner panel 22 (see FIG. 3).
[0022]
【The invention's effect】
Since the method for repairing a polygonal column structure according to the present invention is as described above, the following effects can be obtained.
<B> After the flat panel is disposed on the flat surface of the polygonal column structure, the joint between the flat panels may be covered with the corner panel. For this reason, it is possible to arrange the panels at the corners in a short time, and the work can be efficiently performed even when the work time for subway construction or the like can be ensured only for several hours.
<B> Since high-quality panels produced in the factory can be used, work on site is minimized and high-quality repairs can be made.
<C> Since the corner panel is fitted between the outer panels to cover the joint portion of the flat panel, the corner portion serving as the joint portion does not become too large, and the joint portion is unlikely to become a weak portion.
<D> Since a panel having a composite structure is used, the strength and material can be freely adjusted according to the required strength, shape, or usage environment.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of an embodiment of a method for repairing a polygonal column structure according to the present invention.
FIG. 2 is a cross-sectional view of an embodiment of a method for repairing a polygonal column structure according to the present invention.
FIG. 3 is an explanatory diagram of an embodiment of a method for repairing a beam-like polygonal column structure.
FIG. 4 is an enlarged cross-sectional view of a corner portion in an embodiment of a conventional column repair method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Polygonal column structure 1a .. Polygonal column structure 1b .. Polygonal column structure 2 ... Structural panel 21 .. Plane panel 211. Inner panel 212. Outer panel 213. Reinforcement layer 22 .. Corner Panel 3 for joints

Claims (2)

In the repair method of the polygonal column structure that covers the outer periphery of the polygonal column structure having a plurality of corners with a panel,
A structural panel having a reinforcing layer sandwiched between two basic panels, wherein at least one of the end portions of the inner panel protrudes from the outer panel and the reinforcing layer is exposed, the planar panel is a plane of the polygonal column structure. Each with a predetermined interval in front of the part,
Between the outer panel of the flat panel disposed across the corner, fitted corners panel to suit and the angle of the corner has a reinforcing layer on the inside,
Filling a bonding material between the polygonal column structure and the flat panel,
How to repair polygonal column structures. In the repair method of the polygonal column structure according to claim 1,
The planar panels arranged across the corners are joined at the ends of the inner panels,
How to repair polygonal column structures.

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