JP6846147B2 - Reinforcement or repair method of stepped support and stepped support that has been reinforced or repaired - Google Patents

Description

The present invention relates to a method for reinforcing or repairing a stepped column, and a reinforced or repaired stepped column. More specifically, the present invention relates to reinforcement or repair of stepped columns in which columns having different outer peripheral diameters are connected to each other.

Metal or concrete such as carbon steel pipes for general structures is used for the columns of signs and lighting facilities called road accessories. It is known that cross-section defects due to corrosion progress in such columns as they age. It is desirable to rebuild such aging pillars as soon as possible, but the cost of rebuilding is generally high, and measures for reinforcement or repair are considered as a temporary extension of life until rebuilding.

It is important that reinforcement or repair is performed especially on the road surface boundary where there is a lot of contact with the cause of corrosion and the frequency of column corrosion is high from the viewpoint of preventing sudden collapse.
As a specific reinforcement or repair method for such a portion, a method of winding and adhering a steel plate around a support column has been known for some time. Further, as shown in FIG. 4 of Japanese Patent Application Laid-Open No. 2006-336393 (Patent Document 1), a method of attaching a reinforcing fiber sheet with a resin is also known.

On the other hand, a special structure (stepped portion) in which poles having different diameters at the top and bottom are connected to the metal columns used for road accessories, etc., as shown in Japanese Patent Application Laid-Open No. 7-26537 (Patent Document 2). A structure having a structure) is known.

Japanese Unexamined Patent Publication No. 2006-336393 Jikkenhei 7-26537

A strut having the above-mentioned special structure may crack at a corner of a stepped portion. Therefore, an object of the present invention is to provide a technique for reinforcing or repairing a stepped column by effectively reinforcing the stepped column having a special structure.

In order to achieve the above object, the present invention includes the following inventions.

(1)
The method for reinforcing or repairing a stepped column of the present invention includes a filler layer forming step and a fiber reinforced resin layer forming step.
In the filler layer forming step, the first strut and the second strut having different outer peripheral diameters have a stepped portion connected in the axial direction, and the outer peripheral diameter of the second strut is 1 of the outer peripheral diameter of the first strut. A layer of filler that smoothly connects the outer peripheral surface of the first column and the outer peripheral surface of the second column is formed at least in the corner of the stepped portion with respect to the stepped column that is 4 times or more and 5.0 times or less. To do.
In the fiber-reinforced resin layer forming step, a fiber-reinforced resin layer is formed along the outer peripheral surface of the first column and the surface of the second column and in contact with the filler layer.

By forming the fiber-reinforced resin layer by interposing a layer of the filler between at least the corners in this way, the stepped column can be effectively reinforced. Further, the filling of the filler layer between the fiber reinforced resin layer and the corner portion in the stepped portion avoids the mixing of air between the fiber reinforced resin layer and the corner portion, and is like dew condensation. It also makes it possible to prevent the occurrence of phenomena that cause deterioration. Furthermore, since at least the corners are covered with the filler layer and the fiber reinforced resin layer, the corners where deterioration factors (for example, water, flying objects, etc.) are naturally likely to accumulate and the risk of corrosion is high are effectively effective. Can be protected.

Reinforcement refers to a process for imparting mechanical characteristics improved from the sound state (non-deteriorated state) of the stepped column regardless of the degree of deterioration of the stepped column, and repair means stepping. A process for recovering the deterioration of mechanical properties due to deterioration of columns to the same level as in a healthy state (non-deteriorated state).

(2)
In the method of reinforcing or repairing the stepped column of the above (1), in the filler layer forming step, at least the corners of the stepped portion are coated with the filler to form the filler layer, and the fiber reinforced resin layer forming step is performed. In, a fiber reinforced resin sheet may be attached along the outer peripheral surface of the first column, the surface of the formed filler layer, and the outer peripheral surface of the second column to form the fiber reinforced resin layer.

In this case, the construction is easy because the filler is applied to the corners in advance. Further, since the fiber reinforced resin sheet is attached on the coated filler, it is difficult for bubbles to be formed between the filler and the fiber reinforced resin sheet.

(3)
In the method for reinforcing or repairing the stepped column of the above (1), the filler layer forming step may be performed after the fiber reinforced resin layer forming step. In this case, in the fiber-reinforced resin layer forming step, the fiber-reinforced resin cured product is used as the stepped column so as to form a space along the outer peripheral surface of the first column and the surface of the second column and where the filler layer is provided. In the step of fixing and forming the filler layer, the space is filled with the filler.

In this case, construction is easy in that a fiber-reinforced resin cured product that has been molded in advance into a shape that exerts a reinforcing effect is used.

(4)
The method for reinforcing or repairing the stepped column according to any one of the above (1) to (3) is a corner portion of the fiber reinforced resin layer formed along the filler layer in the cross section including the axis of the stepped column. The minimum radius of curvature in is 10 mm or more.

As a result, the curvature of the bent portion of the fiber reinforced resin layer corresponding to the corner portion becomes small, and stress concentration in the corner portion can be effectively avoided.

(5)
In the method for reinforcing or repairing the stepped column of the above (2), the fiber reinforced resin sheet may be a semi-cured prepreg sheet.

In this case, since the fiber-reinforced resin sheet is flexible, it is easy to form a curved surface such as a bent portion around a corner portion.

(6)
The method for reinforcing or repairing the stepped column according to any one of (1) to (5) above is such that the end portion of the fiber reinforced resin layer on the first strut side is thickened toward the end on the first strut side. It may be configured in.

As a result, at the end of the fiber-reinforced resin layer on the first strut side, a sudden change in rigidity in the longitudinal direction of the stepped strut is prevented, so that the occurrence of local buckling can be satisfactorily suppressed.

(7)
The method for reinforcing or repairing the stepped column according to any one of (1) to (6) above is performed on the axis of the first column of the outer surface of the fiber reinforced resin layer in the cross section including the axis of the stepped column. The length of the portion along the axis and the length of the portion along the axis of the second strut may be larger than the inherent fixing length of the fiber reinforced resin layer, respectively.

As a result, the reinforcing effect of the fiber reinforced resin layer can be more satisfactorily exhibited.

(8)
The reinforced or repaired stepped column of the present invention includes a stepped column, a filler layer, and a fiber reinforced resin layer.
The stepped strut has a stepped portion in which the first strut and the second strut having different outer peripheral diameters are connected in the axial direction, and the outer peripheral diameter of the second strut is 1.4 of the outer peripheral diameter of the first strut. It is more than double and 5.0 times or less.
The filler layer smoothly connects the outer peripheral surface of the first strut and the outer peripheral surface of the second strut, which are filled at least in the corners of the stepped portion.
The fiber reinforced resin layer is provided along the outer peripheral surface of the first strut, the surface of the filler layer, and the outer peripheral surface of the second strut.

By providing the fiber reinforced resin layer in this way, the stepped columns can be effectively reinforced in strength. Further, since the filler layer is filled between the fiber reinforced resin layer and the corner portion in the stepped portion, air is prevented from being mixed between the fiber reinforced resin layer and the corner portion, and dew condensation occurs. It is also possible to prevent the occurrence of a phenomenon that causes deterioration. Furthermore, since at least the corners are covered with a layer of filler and a fiber-reinforced resin layer, it is effective to use corners where deterioration factors (for example, water, flying objects, etc.) are inherently likely to accumulate and the risk of corrosion is high. Can be protected.

(9)
In the stepped column reinforced or repaired in (8) above, the minimum radius of curvature at the corner of the fiber reinforced resin layer provided along the filler layer is 10 mm or more in the cross section including the axis of the stepped column. It may be.

As a result, the curvature of the bent portion of the fiber reinforced resin layer corresponding to the corner portion becomes small, and stress concentration in the corner portion can be effectively avoided.

(10)
The stepped support column (8) or (9) above has a tapered shape in which the end portion of the fiber reinforced resin layer on the first column side decreases in thickness toward the end on the first column side. It's okay.

As a result, at the end of the fiber reinforced resin on the first strut side, a sudden change in rigidity in the longitudinal direction of the stepped strut is prevented, so that the occurrence of local buckling can be satisfactorily suppressed.

(11)
The stepped column reinforced or repaired according to any one of (8) to (10) above is located on the axis of the first column of the outer surface of the fiber reinforced resin layer in the cross section including the axis of the stepped column. The length of the portion along the axis and the length of the portion along the axis of the second strut may be larger than the inherent fixing length of the fiber reinforced resin layer, respectively.

As a result, the reinforcing effect of the fiber reinforced resin layer can be more satisfactorily exhibited.

A schematic cross-sectional view of the stepped column reinforced or repaired according to the first embodiment is shown. The schematic external perspective view of the stepped column to be reinforced or repaired in 1st Embodiment is shown. A schematic cross-sectional view of the stepped column reinforced or repaired according to the second embodiment is shown. A schematic cross-sectional view of the stepped column reinforced or repaired according to the third embodiment is shown. A schematic cross-sectional view (part) of the stepped column reinforced or repaired according to the fourth embodiment is shown. The schematic cross-sectional view (part) of the stepped column which was reinforced or repaired of the modified example of 4th Embodiment is shown. A schematic explanatory view of a method for reinforcing or repairing a stepped support according to a fifth embodiment is shown. A schematic explanatory view of the method for reinforcing or repairing the stepped column of the sixth embodiment is shown. A schematic cross-sectional view of the stepped columns in Examples 1 to 3 and Comparative Examples 1 and 2 and a partially enlarged view thereof are shown. The schematic cross-sectional view of the stepped column which was reinforced or repaired in Example 1 and Example 2 is shown. A partially enlarged view of a schematic cross-sectional view of the stepped column reinforced or repaired in Example 3 is shown.

[1. 1st Embodiment-Reinforced or repaired stepped column]
FIG. 1 shows a stepped strut (hereinafter, stepped strut reinforcing body) reinforced or repaired according to the first embodiment as a schematic cross-sectional view on a surface including an axial center of the stepped strut. FIG. 2 shows a schematic external perspective view of a stepped column to be reinforced or repaired according to the present embodiment.

The stepped column reinforcing body 100 shown in FIG. 1 includes a stepped column 900, a filler layer 200, and a fiber reinforced resin layer 300.

[1-1. Stepped support]
The stepped stanchion 900 may be a road attachment, more specifically including stanchions for signs and lighting facilities. The material of the stepped support 900 is not particularly limited as long as it is corrosive, and may be, for example, metal or concrete.
As shown in FIGS. 1 and 2, the stepped column 900 includes an upper column 910 and a lower column 920. The outer peripheral diameters of the upper strut 910 and the lower strut 920 are different from each other, and the outer peripheral diameter R2 of the lower strut 920 (excluding the outer peripheral diameter around the upper end 921 described later) is 1.4 times or more the outer peripheral diameter R1 of the upper strut 910. It is 0 times or less. The lower strut 920 is configured such that the outer peripheral diameter gradually decreases toward the upper end 921 around the upper end 921, and the corner portion 952 forms a smooth curved surface. In the present embodiment, the curved surface is configured so that the minimum radius of curvature r _e of the corner portions of the fiber-reinforced resin layer 300 to be described later becomes a predetermined range. The outer peripheral diameter of the upper end 921 of the lower strut 920 substantially matches the outer peripheral diameter of the upper strut 910.

In this way, the upper strut 910 and the lower strut 920, which have different outer peripheral diameters, are connected in the axial direction, so that the connecting portion constitutes a stepped portion. The stepped portion constitutes a corner portion 951 when viewed from the outer peripheral surface side. In the present embodiment, the corner angle θ is an angle formed by the outer surface of the upper strut 910 and the contact surface at the upper end 921 of the outer surface of the lower strut 920 on the cut surface including the axial center of the stepped strut 900. The corner angle θ _i is not particularly limited and may be, for example, 90 degrees or more.

[1-2. Filler layer]
In the present embodiment, the filler layer 200 is provided at the corner 951 of the stepped portion. As shown in FIG. 1, the filler layer 200 smoothly connects the outer surface of the upper strut 910 and the outer surface of the lower strut 920 to soften the step at the corner 951. Smoothly connecting in the present invention means connecting with a smooth surface (curved surface or flat surface) so that the outer peripheral diameter of the filler layer 200 filled in the corner 951 always increases from the top to the bottom. ..

The filler layer 200 is composed of, for example, a cured product of a filler selected from the group consisting of a resin composition and a cement composition. The resin composition is not particularly limited as long as it has an adhesive ability to both the stepped column 900 and the fiber reinforced resin layer 300. A resin composition containing an epoxy resin as a main component is preferable. Cement compositions include cement, mortar and concrete.

[1-3. Fiber reinforced plastic layer]
The fiber reinforced resin layer 300 is provided along the outer peripheral surface of the upper strut 910, the surface of the filler layer 200, and the outer peripheral surface of the lower strut 920. The surface of the fiber reinforced resin layer 300 also forms a smooth curved surface. Minimum radius of curvature _{r i} at the corners of the fiber-reinforced resin layer 300 formed along the filler layer 200, 10 mm or more, preferably 20mm or more. As a result, the curvature of the bent portion of the fiber reinforced resin layer 300 corresponding to the corner portion 951 is reduced, and stress concentration on the bent portion can be effectively avoided. Thereby, the compressive strength or the tensile strength of the fiber reinforced resin layer 300 can be effectively exhibited. The maximum value of the minimum curvature within a radius r _i in the corners is not limited, infinite (i.e. the curvature is zero) it may be.

Minimum curvature radius _{r e} of the corner portions of the fiber-reinforced resin layer 300, 10 mm or more, preferably 20mm or more. As a result, it is possible to more effectively prevent a decrease in strength due to bending of the reinforcing fibers.

The fiber reinforced resin layer contains a reinforcing fiber and a cured body of the resin impregnated therein. The reinforcing fiber is not particularly limited, and examples thereof include glass fiber, aramid fiber, and carbon fiber. The reinforcing fibers are preferably long fibers oriented in the vertical direction. This facilitates the formation of a smooth curved surface shape of the filler layer 200 at the corner 951 and facilitates the development of reinforcing reinforcement. The resin is not particularly limited, but may be, for example, an epoxy resin.

Of the outer surface of the fiber reinforced resin layer 300, the length L1 of the portion along the axis of the upper strut 910 and the length L2 of the portion along the axis of the lower strut 920 are unique to the fiber reinforced resin layer 300, respectively. It is preferably larger than the fixing length. More preferably, the length L1 and the length L2 may be 200% or more of the fixing length, respectively. As a result, the reinforcing effect of the fiber reinforced resin layer 300 can be more satisfactorily exhibited.

[2. 2nd Embodiment-Reinforced or repaired stepped column]
FIG. 3 shows the stepped column reinforcing body of the second embodiment as a schematic cross-sectional view of the surface including the axial center of the stepped column.
The stepped column reinforcing body 100a shown in FIG. 3 is provided on the entire outer surface of the stepped column 900 covered with the fiber reinforced resin layer 300a as well as the corner 951 of the filler layer 200a. It is the same as the first embodiment.

In the present embodiment, at the upper end 311a of the fiber reinforced resin layer 300a, it is preferable that the thickness of the filler layer 200a interposed between the fiber reinforced resin layer 300a and the stepped column 900 is as small as possible. As a result, it is possible to prevent foreign substances such as water and dust from accumulating on the upper end 311a surface of the fiber reinforced resin layer 300.

In this embodiment, the filler layer 200a is interposed between the fiber reinforced resin layer 300a and the stepped column 900 in both the corner portion 951 and the other portions, but the present embodiment is not limited to this embodiment. As a modification, a cured layer of an adhesive different from the filler may be interposed in a portion other than the corner portion 951.

[3. Third Embodiment-Reinforced or repaired stepped column]
FIG. 4 shows the stepped column reinforcing body of the third embodiment as a schematic cross-sectional view of the surface including the axial center of the stepped column.
The stepped column reinforcing body 100b shown in FIG. 4 is the same as that of the first embodiment except that the structure of the lower column of the stepped column to be reinforced is different.

The stepped support 900b in the stepped support reinforcing body 100b includes an upper support 910 and a lower support 920b. The upper end 921b of the lower support 920b forms a tubular wall, and the upper support 910 is connected to the central hole of the tubular wall. The corner angle θ _i b of the corner 951 b and the corner angle θ _e b of the corner 952 b are both 90 degrees.

In the present embodiment, since the corner portion 952b forms the corner portion angle θ _e b as described above, in the filler layer 200b, the minimum radius of curvature at the corner portion of the fiber reinforced resin layer 300b is the above-mentioned minimum radius of curvature. It is formed so as to form the r _e.

[4. Fourth Embodiment-Reinforced or repaired stepped column]
FIG. 5 shows a schematic partially enlarged view of the stepped support support body of the fourth embodiment, and FIG. 6 shows a modified example thereof. 5 and 6 show an enlarged portion (near the upper end portion of the fiber reinforced resin layer) corresponding to the square box portion in FIG. 1.

The stepped support support body 100c shown in FIG. 5 is the same as that of the first embodiment except that the upper end portion 310c of the fiber reinforced resin layer 300c is formed in a tapered shape in which the thickness decreases toward the upper end 311c. Is. Since the upper end portion 310c of the fiber reinforced resin layer 300c is tapered in this way, the upper end portion 310c of the fiber reinforced resin layer 300c prevents a sudden change in rigidity in the longitudinal direction of the stepped column 900. .. Therefore, the occurrence of local buckling can be satisfactorily suppressed.

The stepped support support body 100d shown in FIG. 6 is the same as that of the first embodiment except that the upper end portion 310d of the fiber reinforced resin layer 300d is configured to decrease in thickness toward the upper end 311d. is there. The fiber-reinforced resin layer 300d is a laminate of a plurality of fiber-reinforced resin layers, and each fiber-reinforced resin layer is laminated so that the upper end 311d side becomes shorter toward the outside. As a result, the upper end portion 310d of the fiber reinforced resin layer 300d prevents a sudden change in rigidity in the longitudinal direction of the stepped column 900. Therefore, the occurrence of local buckling can be satisfactorily suppressed.

[5. Fifth Embodiment-Reinforcement or repair method of stepped column]
FIG. 7 shows a schematic view illustrating a method of reinforcing or repairing the stepped column of the fifth embodiment. FIG. 7 shows a method of reinforcing or repairing the stepped column 900 to construct the stepped column reinforcing body 100 of the first embodiment. The outer surface of the stepped column 900 may be surface-treated in advance to remove rust and dirt by polishing.

In the method of the present embodiment, the filler layer forming step and the fiber reinforced resin layer forming step are performed.
In the filler layer forming step, the filler 200'is applied to the corner portion 951. The filler 200'is selected from the group consisting of resin compositions and cement compositions.

In the present embodiment, the filler 200'is applied so as to be placed on the corner 951, and before the fiber-reinforced resin sheet 300' described later is attached, the surface of the applied filler 200'is applied to the surface of the upper support column 910 and the surface of the upper column 910. A layer of filler 200'may be formed by leveling so as to smoothly connect to the surface of the lower support column 920. In this case, the fiber reinforced resin layer forming step is performed after the filler layer forming step.
Alternatively, the filler 200'is applied so as to be placed on the corner 951 and roughly leveled, and when the fiber reinforced resin sheet 300' described later is attached, the surface of the filler 200' is topped above the fiber reinforced resin sheet 300'. A layer of filler 200'may be formed by leveling the surface of the support column 910 and the surface of the lower support column 920 so as to be smoothly connected to each other. In this case, the filler layer forming step and the fiber reinforced resin layer forming step are not separate steps but are performed in the same step.

In the fiber reinforced resin layer forming step, the fiber reinforced resin sheet 300'is attached. The fiber reinforced resin sheet 300'is a semi-cured prepreg sheet impregnated with an uncured resin. Since the fiber-reinforced resin sheet 300'is flexible, it can be easily attached and a curved surface can be easily formed. Therefore, there is a high degree of freedom regarding the outer surface shape of the stepped column. Further, since the fiber-reinforced resin sheet 300'is flexible, it becomes easy to prevent air bubbles from being mixed. Further, since the fiber reinforced resin sheet 300'itself has adhesiveness, it can be directly attached to the stepped column 900 of the portion where the filler 200' is not applied.

After the filler layer forming step and the fiber reinforced resin layer forming step are completed, the filler 200'layer and the fiber reinforced resin sheet 300' are cured by curing, respectively, and the filler layer 200 and the fiber reinforced resin layer are cured. Form 300 (see FIG. 1).

The method of this embodiment is a method of constructing the stepped column reinforcing body 100 of the first embodiment, but when the stepped column reinforcing bodies 100b, 100c, 100d of the third embodiment and the fourth embodiment are constructed. Is applied in the same way.
On the other hand, when the stepped support support body 100a of the second embodiment is constructed, the filler 200'is applied not only to the corner portion 951 but also to the portion to which the fiber reinforced resin sheet 300'is to be attached. In this case, the filler to be applied may be applied so as to slightly protrude from the area to be applied of the fiber reinforced resin sheet 300'. As a result, it is difficult for a gap to be formed between the fiber reinforced resin sheet 300'and the stepped column 900.
Further, in this case, the fiber reinforced resin sheet 300'may be a sheet having no surface adhesiveness.

[6. Sixth Embodiment-Reinforcement or repair method of stepped column]
FIG. 8 shows a schematic view illustrating a method of reinforcing or repairing the stepped column of the sixth embodiment. FIG. 8 shows a method of reinforcing or repairing the stepped column 900 to construct the stepped column reinforcing body 100a of the second embodiment.

In the present embodiment, the fiber reinforced resin layer forming step and the filler layer forming step are performed in this order. In the fiber reinforced resin layer forming step, the fiber reinforced resin cured body 300a ″ is fixed to the stepped column 900. The fiber-reinforced resin cured product 300a ″ is preformed into a shape capable of forming a space S along the outer peripheral surface of the upper support column 910 and the surface of the lower support column 920 and in which a layer of a filler is provided. The fiber-reinforced resin cured body 300a ″ can be fixed by applying a filler or an adhesive applied to the surface of the stepped column 900 and further using a fixing member such as a band 390a ″ if necessary. The filler or adhesive to be applied may be applied so as to slightly protrude from the planned coating area of the fiber-reinforced resin cured product 300a''. As a result, it is difficult for a gap to be formed between the fiber-reinforced resin cured body 300a'' and the stepped support 900.
In the filler layer forming step, the filled space S is filled with the filler to form a layer of the filler.

After the filler layer forming step and the fiber reinforced resin layer forming step are completed, the filler layer is cured by curing to form a filler layer 200a (see FIG. 3), respectively.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.
[Example 1]
(Assumed stepped support)
As the stepped support 900e (see FIG. 9), a steel structure with reference to JIL1002, explanatory diagram 1, and joining method 1 was assumed. Specifically, the stepped support 900e has two straight pipes having different outer diameters (upper support straight pipe A: outer diameter 89.1 mm, length 3228 mm; lower support straight pipe B: outer diameter 165.2 mm, The length 1712 mm) is arranged so that it is coaxial and the overlap of both axes is 177 mm, and the diameter-reduced pipe C (the outer surface has a radius of 38.05 mm) connecting the straight pipe B for the lower strut to the straight pipe A for the upper strut. The axis of the rotating surface is a straight line parallel to the straight line connecting the end and the center of the arc and separated by 44.55 mm from the straight line, and is straight for the upper strut. It is connected by a pipe A and a straight pipe B for the lower support (corresponding to the axis). The outer surface of the reduced diameter pipe C is smoothly continuous with the surface of the straight pipe B for the lower strut, while the outer surface of the reduced diameter pipe C and the surface of the straight pipe A for the upper strut are connected in an orthogonal state. A weld bead is assumed for the connection between the outer surface of the reduced diameter pipe C and the surface of the straight pipe A for the upper strut, and the bead portion D has a cross section including the axis of the stepped strut 900e centered on the intersection line I on both sides. It has a fan-shaped shape with a radius of 5 mm.
As described above, in the stepped support 900e, the exposed portion of the upper support straight pipe A is formed as the upper support 910e, and the welded body of the lower support straight pipe B and the reduced diameter pipe C is formed as the lower support 920e. .. For the structure of the portion where the straight pipe A for the upper strut and the straight pipe B for the lower strut overlap inside the stepped strut 900e, the above standard was referred to.

In the load test described later, the stepped support 900e is loaded with the load F in the horizontal direction with respect to the crown. The lower end of the lower support 920e was treated as a fixed end. The material of the stepped support 900e was assumed to be SS400, and the physical properties were an elastic modulus of 200 GPa, a Poisson's ratio of 0.29, a density of 7820 kg / m ³ , and a strength of 400 MPa.

(Assumed stepped support reinforcement)
It is assumed that the stepped column reinforcing body 100e is provided with the filler layer 200a (similar to that in FIG. 3) and the fiber reinforced resin layer 300e on the stepped column 900e. The fiber reinforced resin layer 300e has a two-layer structure with an adhesive layer AD interposed therebetween. FIG. 10 shows a cross-sectional view of the stepped support support body 100e with a surface including an axial center.
The longitudinal dimension of the fiber reinforced resin layer 300e is the length from the position corresponding to the upper end of the straight pipe B for the lower column to the lower end of the fiber reinforced resin layer 300e on the lower column 920e side (corresponding to L2 in FIG. 10). On the upper strut 910e side, the surface of the fiber reinforced resin layer 300e from the vicinity of the corner 951e to the upper end 311e of the fiber reinforced resin layer 300e is along the axis of the straight pipe A for the upper strut. (Length corresponding to L1 in FIG. 10) was set to 192.14 mm. The circumferential dimension of the fiber reinforced resin layer 300a is determined so that the inner layer of the two layers is the peripheral length of the outer surface of the filler layer 200a, and the outer layer is the inner laminated layer AD. It was determined to be the circumference of the outer surface of the layer.

Stepped strut reinforcement 100e, the fiber-reinforced resin layer 300e minimum radius of curvature ri is 15mm in the corners 951E, the arc center angle θs in contact with the outer surface of the radius _{r i} fiber reinforced resin layer 300e has a 72. It was 36 °.

The fiber reinforced resin layer 300e is assumed to be a cured product of a CFRP sheet in which the reinforcing fibers are oriented only in the longitudinal direction of the stepped column 900e and the matrix resin is an epoxy resin, and the physical properties of each layer of the fiber reinforced resin layer 300e are The elastic modulus was 60 GPa, the Poisson's ratio was 0.3, the density was 1.36 kg / m ³ , and the strength was 880 MPa.

Further, it is assumed that the filler layer 200a is provided with a thickness of 0.3 mm except for the corner portion 951e. It is assumed that the adhesive layer AD is provided with a thickness of 0.3 mm. The materials of the filler layer 200a and the adhesive layer AD were the same, and the elastic modulus was 2 GPa, the Poisson's ratio was 0.3, the density was 1.1 kg / m ³ , and the strength was 65 MPa. It was assumed that the fiber reinforced resin layer 300a and the surface of the stepped support support body 100e were fixed to each other via the filler layer 200a and the adhesive layer AD (the analysis of the peeling behavior in consideration of the physical properties related to adhesion was omitted). ..

(Load test)
When a constant load F (load 606N) is applied in the horizontal direction to the climbing portion of the stepped column reinforcing body 100e assumed as described above, the stepped column reinforcing body 100e, the fiber reinforced resin layer 300e, the filler layer 200a, and the adhesive The maximum generated stress of the material layer AD was determined by analysis. The analysis was performed by FEM (finite element method) analysis using Abaqus / Standard 6.14.

[Example 2]
Fiber-reinforced resin layer 300e minimum radius of curvature _{r i} of about 40.5mm of the corners 951E, that the central angle θs of the arc in contact with the outer surface of the fiber reinforced resin layer 300e has the radius _{r i} and 45 ° Except for this, the analysis was performed assuming a stepped column reinforcing body 100e in the same manner as in Example 1. The length corresponding to L1 (see FIG. 10) was 152.31 mm.

[Example 3]
It is assumed that the stepped column reinforcing body 100f is provided with the fiber reinforced resin layer 300f on the stepped column 900e. FIG. 11 shows a cross-sectional view of the upper end portion 310f of the stepped support support body 100f. The inner layer of the fiber reinforced resin layer 300f has a length such that the upper end 311f is located approximately 226 mm upward from the intersection line I between the outer surface of the straight pipe A for the upper strut and the outer surface of the reduced diameter pipe C, and the outer layer is The length is set so that the upper end is located 40 mm below the upper end 311f. The stepped column reinforcing body 100f was analyzed in the same manner as in Example 1. The length corresponding to L1 (see FIG. 11) was 212.14 mm.

[Comparative Example 1]
The stepped support 900e not provided with the fiber reinforced resin layer was analyzed in the same manner as in Example 1.

[Comparative Example 2]
The analysis was performed in the same manner as in Example 1 except that the adhesive layer was provided instead of the filler layer 200a. This adhesive layer was provided at the corner portion 951e with a thickness of 0.3 mm along the outer surfaces of the straight pipe A for the upper strut, the diameter-reduced pipe C, and the bead portion D. In this comparative example, since the fiber reinforced resin layer is attached along the outer surface of the bead portion D, there is no configuration corresponding to the filler layer at the corner portion 951e, and the minimum radius of curvature r at the corner portion 951e. _i is 0 mm. The length corresponding to L1 (see FIG. 10) was 199.06 mm.

[Analysis result]
Table 1 shows the FEM analysis results of Examples 1 to 3 and Comparative Examples 1 and 2 described above. The positions a to e indicating the position where the maximum generated stress is generated are as follows.
a: Near the intersection of the outer surface of the straight pipe A for the upper strut and the outer surface of the bead portion D b: Near the upper end of the fiber reinforced resin layer c: The outer surface of the straight pipe A for the upper strut and the reduced diameter pipe C Around 100 mm upward from the intersection line I with the outer surface d: Around 55 mm upward from the intersection line I between the outer surface of the straight pipe A for the upper strut and the outer surface of the reduced diameter pipe C e: The inner layer of the fiber reinforced resin layer Near the upper end

In the stepped column 900e (Comparative Example 1) in which the fiber reinforced resin layer is not provided, the maximum stress of 235 MPa is generated at the position a, whereas the fiber reinforced resin layer and the filler layer at the corners are provided. In both Examples 1 and 3, the stress was 156 MPa at the position a and 117 MPa at the position c in Example 2, and it was found that the generated stress could be significantly relaxed in each of the examples. Further, it was found that in Examples 1 and 3 and Example 2, the generated stress can be more significantly relaxed in Example 2 in which the minimum radius of curvature is larger.
On the other hand, in Comparative Example 2 in which the fiber reinforced resin layer was provided but the filler layer at the corner was not provided, the maximum generated stress at the position a was 207 MPa, which was still a high value.

Further, the maximum generated stress of the filler layer of the inner layer of the fiber reinforced resin layer in Examples 1 and 3 is both near the upper end of the fiber reinforced resin layer, and the magnitude of the stress is smaller in Example 3. Therefore, by staggering the upper ends of the inner layer and the outer layer, the stress generated in the filler layer is alleviated, and peeling from the upper end of the fiber reinforced resin layer, which is generally assumed fracture, is suppressed. It was suggested that it could be done.

Preferred embodiments of the present invention are as described above, but the present invention is not limited thereto, and various other embodiments that do not deviate from the gist of the present invention are made.

[Correspondence between each part in the embodiment and the modified example and each component of the claim]
In the present specification, the stepped column reinforcing bodies 100, 100a, 100b, 100c, 100d, 100e correspond to the "reinforced or repaired stepped column" in the claim, and the filler 200'corresponds to the" filler ". , Filler layers 200, 200a, 200b correspond to "filler layer", fiber reinforced resin sheet 300'corresponds to" fiber reinforced resin sheet ", and fiber reinforced resin cured body 300a'' corresponds to "fiber reinforced resin curing". The fiber reinforced resin layers 300, 300a, 300b, 300c, 300d, 300e, 300f correspond to the "body", the upper end portions 310b, 310c, 310f correspond to the "ends on the first strut side". 311a, 311c, 311d, 311e, 311f correspond to the "first strut side end", and the stepped strut 900, 900b, 900e correspond to the "stepped strut", and the upper strut 910, 910e corresponds to the "first strut", the lower strut 920, 920b, 920e corresponds to the "second strut", the corners 951, 951b correspond to the "corner of the stepped portion", and the outer peripheral diameter R1 is Corresponding to the "outer circumference diameter of the first strut", the outer circumference diameter R2 corresponds to the "outer circumference diameter of the second strut", and the length L1 corresponds to the "length of the portion along the axis of the first strut". the length L2 corresponds to the "length of a portion along the axis of the second support column", the minimum radius of curvature r _i is equivalent to the "minimum radius of curvature at the corner portion of the fiber-reinforced resin layer", space S " It corresponds to "a space where a layer of filler is provided".

100, 100a, 100b, 100c, 100d, 100e Stepped support reinforcement (reinforced or repaired stepped support)
200'Filler 200, 200a, 200b Filler layer 300' Fiber reinforced resin sheet 300a'' Fiber reinforced resin cured product 300, 300a, 300b, 300c, 300d, 300e, 300f Fiber reinforced resin layer 310b, 310c, 310f Upper end (End on the first support column side)
311a, 311c, 311d, 311e, 311f Upper end (first strut side end)
900, 900b, 900e Stepped columns 910,910e Upper columns (first column)
920, 920b, 920e Lower support (second support)
951,951b Corner R1 outer diameter of stepped portion (outer diameter of first strut)
R2 outer diameter (outer diameter of the second support)
L1 length (length of the part along the axis of the first column)
L2 length (length of the part along the axis of the second support)
r _i minimum radius of curvature (minimum radius of curvature at the corner portion of the fiber-reinforced resin layer)
S space (space where a layer of filler is provided)

Claims (9)

The first strut and the second strut having different outer peripheral diameters have a stepped portion connected in the axial direction, and the outer peripheral diameter of the second strut is 1.4 times or more the outer peripheral diameter of the first strut. Filling that forms a layer of a filler that smoothly connects the outer peripheral surface of the first strut and the outer peripheral surface of the second strut at least in the corner of the stepped portion with respect to the stepped strut which is 0.0 times or less. Material layer formation process and
A fiber-reinforced resin layer forming step of forming a fiber-reinforced resin layer along the outer peripheral surface of the first support column and the surface of the second support column and in contact with the filler layer.
Only including,
A method for reinforcing or repairing a stepped column, wherein the minimum radius of curvature at a corner of the fiber reinforced resin layer is 10 mm or more in a cross section including the axis of the stepped column. In the filler layer forming step, the filler is applied to at least the corners of the stepped portion to form the filler layer.
In the fiber-reinforced resin layer forming step, the fiber-reinforced resin sheet is attached along the outer peripheral surface of the first strut, the surface of the formed filler layer, and the outer peripheral surface of the second strut, and the fiber is formed. The method for reinforcing or repairing a stepped column according to claim 1, wherein a reinforced resin layer is formed. The filler layer forming step is performed after the fiber reinforced resin layer forming step,
In the fiber-reinforced resin layer forming step, the fiber-reinforced resin cured product is stepped so as to form a space along the outer peripheral surface of the first column and the surface of the second column and where the filler layer is provided. Fixed to the support,
The method for reinforcing or repairing a stepped column according to claim 1, wherein the space is filled with a filler in the filler layer forming step. The method for reinforcing or repairing a stepped column according to claim 2, wherein the fiber-reinforced resin sheet is a semi-cured prepreg sheet. The aspect according to any one of claims 1 to 4 , wherein the end portion of the fiber reinforced resin layer on the first strut side is configured to decrease in thickness toward the end on the first strut side. How to reinforce or repair stepped columns. In the cross section including the axis of the stepped column, the lengths of the portion of the outer surface of the fiber reinforced resin layer along the axis of the first column and the length of the portion along the axis of the second column are respectively. The method for reinforcing or repairing a stepped column according to any one of claims 1 to 5 , which is larger than the inherent fixing length of the fiber reinforced resin layer. The first strut and the second strut having different outer peripheral diameters have a stepped portion connected in the axial direction, and the outer peripheral diameter of the second strut is 1.4 times or more the outer peripheral diameter of the first strut. With stepped columns that are less than 0.0 times
A filler layer that smoothly connects the outer peripheral surface of the first column and the outer peripheral surface of the second column, which is filled at least in the corner of the stepped portion.
A fiber reinforced resin layer provided along the outer peripheral surface of the first support column, the surface of the filler layer, and the outer peripheral surface of the second support column,
Only including,
A reinforced or repaired stepped column having a minimum radius of curvature of 10 mm or more at a corner of the fiber reinforced resin layer in a cross section including the axis of the stepped column. The reinforced or repaired stepped strut according to claim 7 , wherein the end portion of the fiber reinforced resin layer on the first strut side is tapered toward the end on the first strut side. In the cross section including the axis of the stepped column, the lengths of the portion of the outer surface of the fiber reinforced resin layer along the axis of the first column and the length of the portion along the axis of the second column are respectively. The reinforced or repaired stepped column according to claim 7 or 8 , which is larger than the inherent fixing length of the fiber reinforced resin layer.

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