JP4491163B2 - Opening reinforcement structure for reinforced concrete plate members - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an opening reinforcing structure for a reinforced concrete plate member suitable for a reinforced concrete wall and a slab.
[0002]
[Prior art]
In general, when the opening 11 is provided in the reinforced concrete wall 10 as shown in FIG. 12, the rigidity changes suddenly at the corners 12, 12... Of the opening 11, so that the corners 12, 12,. Stress and strain are concentrated.
[0003]
Therefore, when distortion due to dry shrinkage of concrete or distortion due to stress during an earthquake occurs on the wall 10, these distortions are concentrated on the corners 12, 12. Cracks 13 often occur at 12.
[0004]
Therefore, conventionally, a linear reinforcing bar 14 is arranged in the vicinity of the corners 12, 12... Of the wall 10 at a portion where the crack 13 is expected to occur so as to be substantially orthogonal to the crack 13. It was. In FIG. 12, reference numeral 15 denotes a column, and 16 denotes a beam.
[0005]
[Problems to be solved by the invention]
However, although the reinforcement by the conventional reinforcing steel bar 14 is effective in reinforcing the ultimate strength, there is a problem that the effect is low in preventing the occurrence of the crack 13. In particular, when the strength of the concrete increases, the effect of preventing cracks by the reinforcing reinforcing bars 14 decreases.
[0006]
The object of the present invention is to solve such problems, and to provide an opening reinforcing structure for a reinforced concrete plate member capable of preventing cracks generated at the corners of the opening. Is a technical issue.
[0007]
[Means for Solving the Problems]
The present invention is an opening reinforcing structure for a reinforced concrete plate member, and is configured as follows in order to solve the above technical problem. That is, the present invention provides an opening reinforcing structure for a reinforced concrete plate member in which a reinforcing member is provided in the vicinity of a corner portion of the opening in order to reinforce a reinforced concrete plate member having a square opening. It is characterized in that it is formed in a predetermined shape by a rod-like member obtained by solidifying high-strength continuous fibers having a tensile rigidity of 2 times or more with respect to the tensile rigidity of the resin.
[0008]
In the invention, it is preferable that the reinforcing member includes a straight portion, a hook-like portion provided at both ends of the straight portion, and a ring-like portion provided substantially at the center of the straight portion. The portion is arranged so as to be substantially orthogonal to the virtual crack that is expected to occur in the vicinity of the entering corner portion, the reinforcing member is formed in an approximately L shape, and at the tip of the straight portion on both sides thereof A hook-shaped portion and a ring-shaped portion at the intersection of each straight portion, and each straight portion is disposed along the opening edges on both sides of the corner, the reinforcing member is substantially Each of the straight portions is formed in an L-shape, and linear portions on both sides thereof are formed in an elongated U-shape, and hook-shaped portions arranged at positions separated from each other at both ends of the U-shape. Is on both sides of the corner Being disposed along the opening edge, the reinforcing member that is formed in a mesh shape, the high-strength continuous fiber is carbon fiber, said resin is an epoxy resin, characterized by.
[0009]
According to the present invention, since the reinforcing member has a tensile rigidity more than twice the tensile rigidity of the reinforcing bar, the corners of the opening can be sufficiently reinforced, and even if the strength of the concrete is large, the crack is generated. Can be prevented. Further, by setting the shape of the reinforcing member to a predetermined shape, it is possible to increase the adhesion strength with the concrete, thereby increasing the reinforcing effect.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of an opening reinforcing structure for a reinforced concrete plate member according to the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is a view showing a reinforced concrete wall 5 of a first embodiment to which an opening reinforcing structure for a reinforced concrete plate member of the present invention is applied. The reinforced concrete wall 5 is provided with a square opening 51 at a substantially central portion thereof. Further, reinforcing members 53, 53... Described below are embedded in the vicinity of the four corners 52, 52. In addition, the code | symbol 54 in FIG. 1 is a pillar, 55 is a beam.
[0011]
The strong member 53 is a rod-shaped member obtained by solidifying carbon fiber, which is a kind of high-strength continuous fiber, with an epoxy resin into a predetermined shape. This rod-shaped member is provided with a number of irregularities, similar to the deformed reinforcing bar.
[0012]
In addition, carbon fibers having a tensile rigidity more than twice that of a conventional reinforcing bar tensile rigidity of 205 GPa (Young's modulus, reinforced concrete structure calculation standard) are used.
[0013]
As such a carbon fiber, for example, “Torayka Yarn” (trade name) manufactured by Toray Industries, Inc. can be used. Among these “trade card yarns”, types M46J, M50J, and M55J have a tensile rigidity of 436 GPa to 588 GPa (Young's modulus), and have a tensile rigidity of about 2 to 3 times that of the reinforcing bar.
[0014]
In general, in order to prevent cracking of a reinforced concrete plate member, the higher the tensile rigidity of the reinforcing member is, the greater the effect. This is because when the same amount of strain occurs in the concrete and the reinforcing member, the reinforcing member generates a stress that is as large as the ratio of the tensile stiffness, and the surrounding concrete is constrained by this stress, thereby exerting a reinforcing effect. Therefore, the reinforcement effect becomes higher as the tensile rigidity of the reinforcing member is higher than the tensile rigidity of the concrete.
[0015]
The ratio of the tensile strength of the conventional reinforcing steel and concrete was about 10 times. However, the concrete used in current buildings is becoming stronger, and the tensile rigidity of the concrete is higher than before.
[0016]
For this reason, it is necessary to increase the tensile rigidity of the reinforcing reinforcing bars accordingly, but it is currently impossible to increase the tensile rigidity of the reinforcing reinforcing bars. The ratio of tensile rigidity between concrete and reinforced reinforcing bars is reduced to about 5 times, and the reinforcing effect is insufficient.
[0017]
Therefore, in the present invention, by using the reinforcing member 53 having a tensile rigidity more than twice that of the reinforcing bar as described above, the ratio of the tensile rigidity between the high-strength concrete and the reinforcing member 53 is increased to about 10 times, thereby increasing the normal strength. Of course, high-strength concrete as well as high-strength concrete can fully exert its reinforcing effect.
[0018]
On the other hand, the reinforcing effect of the reinforcing member 53 is exhibited by suppressing the increase in distortion of the concrete due to the tensile rigidity of the reinforcing member 53. Therefore, the higher the unity between the reinforcing member 53 and the concrete, the stronger the reinforcing effect. Becomes higher. Therefore, in the present embodiment, as described above, the material of the reinforcing member 53 is provided with a large number of irregularities such as a conventional deformed reinforcing bar, but it is considered difficult to exert a sufficient adhesion force only with the irregularities. .
[0019]
Therefore, as shown in FIG. 2, the reinforcing member 53 of the present embodiment includes a linear portion 60 having an appropriate length, and U-shaped hook-like portions 61 and 61 provided at both ends of the linear portion 60. A flat ring-shaped portion 62 provided at substantially the center of the straight portion 60 is provided.
[0020]
As shown in FIG. 3, the reinforcing member 53 has a straight portion 60 that is substantially perpendicular to a line 56 that is likely to crack in the vicinity of the corner 12 and a ring-shaped portion 62 that is It is arranged so as to overlap the line 56. Thereby, the integrity of the reinforcing member 53 and the concrete can be made as high as possible, and the reinforcing effect can be sufficiently exhibited.
[0021]
Thus, the reinforced concrete wall 5 of the present invention has a tensile strength of the reinforcing member 53 that is twice or more that of a conventional reinforcing bar, so that the reinforcing effect is sufficiently high, and not only ordinary concrete but also high strength Even when concrete is used, it becomes possible to prevent the occurrence of cracks.
[0022]
Further, since the reinforcing member 53 has hook-like portions 61 and 61 on both sides of the straight portion 60 and a flat ring-like portion 62 at the center of the straight portion 60, the adhesion force to the concrete is increased. The reinforcing effect is further increased.
[0023]
Furthermore, since the reinforcing member 53 has a tensile strength 5 to 10 times that of a normal reinforcing bar, a higher ultimate strength can be obtained with a smaller amount of use than a reinforcing bar.
[0024]
Moreover, in this embodiment, since the flat ring-shaped part 62 has been arrange | positioned on the line 56 which is easy to generate | occur | produce a crack, the cross-sectional area of the part which acts directly on reinforcement can be doubled, and the concrete mentioned above Combined with the improvement of the adhesion strength, a high reinforcing effect can be obtained.
[0025]
Moreover, since the specific gravity of carbon fiber is about 1/5 or less of steel materials, the reinforcement member 53 can be made very lightweight. Furthermore, since the reinforcing member 53 has a higher strength than a normal reinforcing bar and can be equal to or less than the same diameter as the reinforcing bar, the reinforcing member 53 can be better accommodated with the wall bars and the slab bars, and does not hinder concrete placement. . Therefore, the reinforcing member 53 can be easily transported and attached, and the workability is very good.
(Second Embodiment)
FIG. 4 shows a reinforced concrete wall 7 of the second embodiment to which the present invention is applied. This reinforced concrete wall 7 is obtained by arranging substantially L-shaped reinforcing members 70, 70... In place of the reinforcing member 53 of the reinforced concrete wall 5 of FIG. Similar to the wall 5.
[0026]
As shown in FIG. 5, the reinforcing member 70 of the reinforced concrete wall 7 is a rod-shaped member formed by solidifying carbon fiber with an epoxy resin in a substantially L shape, and ends of straight portions 71 and 71 on both sides thereof. The part is provided with U-shaped hook-like portions 72, 72. A substantially circular ring-shaped portion 73 is provided at the intersection of the straight portions 71 and 71.
[0027]
As shown in FIG. 6, both the straight portions 71, 71 of the reinforcing member 70 are arranged along the opening edges 57, 58 on both sides of the entrance corner 52 of the opening 51.
[0028]
The reinforced concrete wall 7 has the same effects as the reinforced concrete wall 5 described above.
(Third embodiment)
FIG. 7 shows a reinforced concrete wall 8 according to a third embodiment to which the present invention is applied. The reinforced concrete wall 8 is the same as the reinforced concrete wall 5 except that the reinforcing member 53 of the reinforced concrete wall 5 in FIG. 1 is replaced with a substantially L-shaped reinforcing member 80.
[0029]
As shown in FIG. 8, the reinforcing member 80 has linear portions 81, 81 on both sides formed in an elongated U shape. These straight portions 81 and 81 are joined to portions slightly inside the U-shaped bent end portion, and hook-like portions 82a and 82b disposed at positions separated from each other at both ends. Is provided.
[0030]
As shown in FIG. 9, in the reinforcing member 80, the straight portions 81 and 81 are arranged along the opening edges 57 and 58 on both sides of the corner portion 52.
[0031]
This reinforced concrete wall 8 also has the same effects as the reinforced concrete wall 5 described above.
(Fourth embodiment)
FIG. 10 shows a reinforced concrete wall 9 according to a fourth embodiment to which the present invention is applied. This reinforced concrete wall 9 is the same as the reinforced concrete wall 5 except that the reinforcing member 53 of the reinforced concrete wall 5 in FIG. 1 is replaced with a mesh-like reinforcing member 90.
[0032]
As shown in FIG. 11, the reinforcing member 90 is formed by sticking a plurality of long side members 91 and a plurality of short side members 92 in a mesh shape with a pitch of about 50 mm vertically and horizontally. The shape is a rectangular sheet.
[0033]
As shown in FIG. 10, the reinforcing member 90 has a long side member 91 substantially orthogonal to a virtual crack 56 (FIG. 3) that is expected to be generated in the vicinity of the corner portion 52, and The long side member 91 is disposed so that the substantially central portion thereof is on the virtual crack 56.
[0034]
The reinforced concrete wall 9 has the same effects as the reinforced concrete wall 5 described above, and is characterized by the ease of manufacturing the reinforcing member 90.
[0035]
In the first to fourth embodiments, the case where the present invention is applied to the reinforced concrete walls 5, 7, 8, and 9 has been described. However, the present invention can be applied to plate members such as reinforced concrete slabs. it can.
[0036]
Moreover, in the above-mentioned embodiment, although the rod-shaped member which hardened the carbon fiber with the epoxy resin was used as the reinforcement members 53, 70, 80, 90, it replaced with carbon fiber and has high tensile rigidity more than twice as much as a reinforcing bar. High-strength continuous fibers can be used, and an appropriate resin that can harden the high-strength continuous fibers into a rod shape can be used instead of the epoxy resin.
[0037]
【The invention's effect】
As described above, according to the present invention, since the reinforcing member has a tensile rigidity more than twice that of the reinforcing bar, the corners of the opening can be sufficiently reinforced, and the strength of the concrete can be increased. Even when is large, the occurrence of cracks can be prevented. Moreover, since the adhesion strength with concrete can be increased by setting the shape of the reinforcing member to a predetermined shape, the reinforcing effect can be further increased.
[Brief description of the drawings]
FIG. 1 is a view showing a reinforced concrete wall according to a first embodiment to which an opening reinforcing structure for a reinforced concrete plate member according to the present invention is applied.
FIG. 2 is a view showing a reinforcing member of the first embodiment according to the present invention.
FIG. 3 is a view showing the arrangement of reinforcing members according to the first embodiment of the present invention.
FIG. 4 is a view showing a reinforced concrete wall according to a second embodiment to which an opening reinforcing structure for a reinforced concrete plate member according to the present invention is applied.
FIG. 5 is a view showing a reinforcing member according to a second embodiment of the present invention.
FIG. 6 is a view showing the arrangement of reinforcing members according to a second embodiment of the present invention.
FIG. 7 is a view showing a reinforced concrete wall according to a third embodiment to which an opening reinforcing structure for a reinforced concrete plate member according to the present invention is applied.
FIG. 8 is a view showing a reinforcing member according to a third embodiment of the present invention.
FIG. 9 is a view showing the arrangement of reinforcing members according to a third embodiment of the present invention.
FIG. 10 is a view showing a reinforced concrete wall according to a fourth embodiment to which an opening reinforcing structure for a reinforced concrete plate member according to the present invention is applied. FIG. 11 is a view showing a reinforcing member according to the fourth embodiment according to the present invention. It is.
FIG. 12 is a view showing an opening reinforcing structure for a reinforced concrete wall according to a conventional example.
[Explanation of symbols]
5, 7, 8, 9 Reinforced concrete wall 51 Opening 52 Entrance corner 53, 70, 80, 90 Reinforcing member 56 Virtual crack 57, 58 Opening edge 60, 71, 81 Straight portion 61, 72, 82 Hook-like portion 62, 73 Ring-shaped part

Claims (3)

Have a opening of rectangular, for reinforcing the reinforced concrete plate member high strength concrete is used, in the opening reinforcing structure reinforced concrete plate member provided with a reinforcing member in the vicinity of the inner corner portion of the opening,
The reinforcing member is formed by a rod-shaped member obtained by solidifying high-strength continuous fibers having a tensile rigidity of 2 times or more with respect to the tensile rigidity of the reinforcing bars constituting the reinforced concrete plate member ,
The reinforcing member includes a straight portion, hook-shaped portions provided at both ends of the straight portion, and a ring-shaped portion provided at substantially the center of the straight portion, and the straight portion is the corner portion. An opening reinforcing structure for a reinforced concrete plate member , wherein the ring-shaped portion is arranged so as to overlap the virtual crack, and is arranged so as to be substantially orthogonal to a virtual crack expected to occur in the vicinity of . In order to reinforce a reinforced concrete plate member having a square opening and using high-strength concrete, in the opening reinforcing structure of the reinforced concrete plate member provided with a reinforcing member in the vicinity of the corner of the opening,
The reinforcing member is formed by a rod-shaped member obtained by solidifying high-strength continuous fibers having a tensile rigidity of 2 times or more with respect to the tensile rigidity of the reinforcing bars constituting the reinforced concrete plate member,
The reinforcing member is substantially L-shaped, has hook-shaped portions at the ends of the straight portions on both sides thereof, and has ring-shaped portions at the intersections of the straight portions, and the straight portions have the corners. are arranged along the sides of the opening edge parts, the ring-shaped portion, the opening reinforcement structure of reinforced concrete plate member, characterized in that it is arranged to overlap the virtual crack. The opening reinforcing structure for a reinforced concrete plate member according to claim 1 or 2 , wherein the high-strength continuous fibers are carbon fibers and the resin is an epoxy resin.

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