JP2017101403A - Beam reinforcing material and beam reinforcing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcing material and a reinforcing structure, which can inhibit a shear fracture in a beam of reinforced concrete construction having a through-hole.SOLUTION: In a reinforcing material 13 for reinforcing a beam 11 of reinforced concrete construction having a through-hole 12, at least one of upper and lower parts of the through-hole 12 is provided with a horizontal reinforcement part 31 that is arranged in such a manner that an extension direction Y of the beam 11 is a longitudinal direction, and the horizontal reinforcement part 31 is made of shape steel and a steel plate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a reinforcing material for a reinforced concrete beam having a through hole and a reinforcing structure for the beam.

  When building a reinforced concrete structure, a through hole may be provided in a reinforced concrete beam for equipment piping and inspection. As a method to reinforce a beam having such a through hole, upper and lower reinforcement of the through hole surrounding the upper and lower main bars separately above and below the through hole where the stirrup (beam stirrup) surrounding the main bar becomes sparse There is a technique for arranging hardware (for example, Patent Document 1).

Japanese Patent Laid-Open No. 7-207837

By the way, when a through-hole is provided in the beam, the strength of the upper and lower portions of the through-hole is lowered, and there is a problem that shear failure easily occurs in this portion.
The present invention has been made paying attention to such problems. An object of the present invention is to provide a reinforcing material and a reinforcing structure capable of suppressing shear fracture in a reinforced concrete beam having a through hole.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A reinforcing material for a beam that solves the above problem is a reinforcing material for a reinforced concrete beam having a through hole, and the extending direction of the beam is a longitudinal direction at least one of the upper side and the lower side of the through hole. The horizontal reinforcing portion is formed of a shape steel or a steel plate.

  According to this configuration, the horizontal reinforcing portion made of the shape steel or the steel plate can increase the cross-sectional area that effectively acts on the shear failure of the reinforcing material in the portion where the through hole is provided in the beam. In a reinforced concrete beam having a hole, shear failure can be suppressed.

In the beam reinforcing member, it is preferable that a plurality of holes are provided in the horizontal reinforcing portion.
According to this configuration, since the concrete enters the plurality of holes provided in the horizontal reinforcing portion, the integrity of the horizontal reinforcing portion, which is a shape steel or a steel plate, and the concrete constituting the beam can be enhanced.

The beam reinforcing member preferably includes a shaft member inserted through the hole.
According to this configuration, the shaft member inserted through the hole provided in the horizontal reinforcing portion can enhance the integrity of the horizontal reinforcing portion and the concrete constituting the beam.

  A beam reinforcing material that solves the above problem is a reinforcing material that reinforces a reinforced concrete beam having a through hole, and is disposed so as to surround the horizontal reinforcing portion extending in the extending direction of the beam and the through hole. An annular reinforcing portion.

  According to this structure, it can suppress that a crack arises around a through-hole by the cyclic | annular reinforcement part arrange | positioned so that a through-hole may be enclosed. In addition, the horizontal reinforcement that extends in the extending direction can increase the cross-sectional area of the reinforcing material that effectively works against shear failure, so that shear failure is suppressed in reinforced concrete beams with through-holes. Can do.

In the beam reinforcing member, the annular reinforcing portion preferably has a horizontal portion extending in the extending direction.
According to this configuration, since the annular reinforcing portion has the horizontal portion extending in the extending direction, the shear failure can be effectively suppressed in the reinforced concrete beam having the through hole.

  A reinforcing structure for a beam that solves the above problem is a reinforcing structure for a reinforced concrete beam having a through hole, and the extending direction of the beam is a longitudinal direction at least one of the upper and lower sides of the through hole. The horizontal reinforcing portion is formed of a shape steel or a steel plate.

According to this structure, the same effect as the said reinforcing material can be obtained.
A reinforcing structure for a beam that solves the above problem is a reinforcing structure for a reinforced concrete beam having a through hole, and a horizontal reinforcing portion that extends in the extending direction of the beam, and an annular shape that is disposed so as to surround the through hole. A reinforcing portion.

  According to this structure, the same effect as the said reinforcing material can be obtained.

  According to the present invention, shear failure can be suppressed in a reinforced concrete beam having a through hole.

The schematic diagram which shows 1st Embodiment of the reinforcement structure of a beam and a reinforcing material by a front view. The schematic diagram which shows the structure of the reinforcement structure and reinforcement material of FIG. The schematic diagram which shows the reinforcement structure of FIG. 1, and the structure of a reinforcing material by planar view. The front view which shows the 1st modification of the horizontal reinforcement part of the reinforcing material of 1st Embodiment. The front view which shows the 2nd modification of the horizontal reinforcement part of the reinforcing material of 1st Embodiment. The front view which shows the 3rd modification of the horizontal reinforcement part of the reinforcing material of 1st Embodiment. The side view of the horizontal reinforcement part of FIG. The schematic diagram which shows the 4th modified example of the reinforcement structure of 1st Embodiment, and a reinforcing material by a cross sectional view. The schematic diagram which shows the 5th modified example of the reinforcement structure of 1st Embodiment, and a reinforcing material by a cross sectional view. The schematic diagram which shows the 6th modified example of the reinforcement structure of 1st Embodiment, and a reinforcing material by a cross sectional view. The schematic diagram which shows the 7th modified example of the reinforcement structure of 1st Embodiment, and a reinforcing material by a cross sectional view. The schematic diagram which shows the reinforcement structure of 1st Embodiment, and the 8th modification of a reinforcing material by a cross sectional view. The schematic diagram which shows the 9th modified example of the reinforcement structure of 1st Embodiment, and a reinforcing material by a cross sectional view. The schematic diagram which shows 2nd Embodiment of the reinforcement structure and reinforcement material of a beam by a front view. The schematic diagram which shows the reinforcement structure of FIG. 14, and the structure of a reinforcing material by a cross sectional view. The schematic diagram which shows the reinforcement structure of FIG. 14, and the structure of a reinforcing material by planar view. The front view which shows the 10th modification of the horizontal reinforcement part of the reinforcing material of 2nd Embodiment. The front view which shows the 11th modification of the horizontal reinforcement part of the reinforcing material of 2nd Embodiment.

Hereinafter, embodiments of reinforcing members and reinforcing structures for reinforced concrete beams having through holes will be described with reference to the drawings.
(First embodiment)
As shown in FIG. 1, a reinforced concrete beam 11 has an extending direction Y in the horizontal direction, and a through hole 12 formed in an axial direction X that intersects the extending direction Y, and a reinforcement that reinforces the beam 11. A material 13, a main reinforcing bar 14 extending in the extending direction Y, a set-up reinforcing bar 15 arranged along the main reinforcing bar 14, and ribs 16 and 17 surrounding the main reinforcing bar 14 so as to be orthogonal to the main reinforcing bar 14. In addition, the beam 11 includes a concrete portion 18 that covers the reinforcing member 13, the main reinforcement 14, the setup reinforcing bars 15, and the stirrups 16 and 17.

  In the installed state of the beam 11, the axial direction X is the direction in which the axial center SC of the through hole 12 extends, and the axial direction X intersects (preferably orthogonally) the extending direction Y, and the axial direction X and the extending direction Each Y intersects the gravity direction Z (preferably orthogonal).

  The through-hole 12 of this embodiment is a hole for people provided in order to perform installation piping on the beam 11 and to inspect it. Although it is recommended that the diameter (outer diameter) of the through hole 12 be 1/3 or less of the beam length (the length from the top end to the bottom end of the beam 11), in this embodiment, the reinforcing material 13 Due to this reinforcing effect, the diameter (for example, 600 mm) of the through hole 12 can be reduced to 1/2 to 1 / 2.5 of the beam.

  If the portion in which the through hole 12 is formed in the extending direction Y of the beam 11 is an opening portion 19, the region away from the opening portion 19 in the extending direction Y is disposed so as to surround the upper and lower main bars 14. Beam stirrups 16 are arranged at predetermined intervals. In addition, in the opening portion 19, an opening portion streak 17 is disposed above and below the through-hole 12 so as to individually surround the upper and lower main reinforcing bars 14 (see also FIG. 2).

  The reinforcing member 13 includes an annular reinforcing portion 21 disposed so as to surround the through hole 12 and a horizontal reinforcing portion 31 extending in the extending direction Y. That is, the reinforced concrete beam 11 having the through hole 12 has a reinforcing structure by the reinforcing material 13.

  The annular reinforcing portion 21 and the horizontal reinforcing portion 31 are preferably connected to each other by welding or the like. This connection may be performed on site, or a reinforcing member 13 integrated in advance by connection may be installed. In the case where the reinforcing member 13 integrated in advance is installed, it is possible to reduce the labor of arrangement compared to the case where the annular reinforcing portion 21 and the horizontal reinforcing portion 31 are individually installed.

  The annular reinforcing portion 21 is preferably formed so as to double surround the through hole 12 by bending one continuous reinforcing bar (preferably a high strength deformed reinforcing bar). In addition, the annular reinforcing portion 21 is located at the upper end portion and the lower end portion and extends in the extending direction Y, and the four side inclined portions 23 that obliquely intersect the gravity direction Z and the extending direction Y. It is preferable to have.

  The horizontal reinforcement part 31 of this embodiment consists of a plate-shaped steel material (steel plate) provided with a plurality of holes 32. By making the horizontal reinforcing portion 31 a steel plate, the cross-sectional area that effectively acts on the shear fracture of the horizontal reinforcing portion 31 in the opening portion 19 becomes larger than when the horizontal reinforcing portion 31 is a reinforcing bar, A high reinforcing effect can be obtained. Further, by providing a plurality of holes 32 in the steel material, the horizontal reinforcing portion 31 can be reduced in weight, and the concrete portion 18 is formed in the hole 32, so that the integrity of the horizontal reinforcing portion 31 and the concrete portion 18 is improved. Can be increased.

  In the present embodiment, a plurality of holes 32 are provided on both end sides in the extending direction Y avoiding the opening portion 19 of the horizontal reinforcing portion 31. In addition, it is also possible to change to the structure which does not equip the horizontal reinforcement part 31 with the hole 32. For example, when the through hole 12 is disposed at a position close to either the top end or the lower end of the beam 11, the horizontal reinforcing portion 31 is disposed only at either the upper side or the lower side of the through hole 12. It may be.

  Here, when shear stress acts on the beam 11, as a result of stress concentration around the through hole 12, first, cracks are generated in the direction of 45 degrees from the axial center SC of the through hole 12. In many cases, the beam 11 is ruptured by a crack in the tangential direction from the edge. Therefore, when the perpendicular line extending in the direction of 45 degrees with respect to the extending direction Y from the axis SC of the through hole 12 and perpendicularly intersecting the circumference of the through hole 12 is a virtual line CR1, the annular reinforcing portion 21 and the horizontal The reinforcing portion 31 is preferably arranged at a position that intersects the virtual line CR1.

  In particular, since the reinforcing effect is high when the reinforcing member 13 is orthogonal to the virtual line CR1, the inclined portion 23 is preferably arranged to be orthogonal to the virtual line CR1. Moreover, when providing the hole 32 in the horizontal reinforcement part 31, it is preferable to provide the hole 32 in the both ends side rather than the virtual line CR1.

  Thereby, even if a crack is generated in the direction of 45 degrees from the center of the through hole 12, it is possible to prevent the fracture of the beam 11 by suppressing the extension of the crack by the inclined portion 23 and the horizontal reinforcing portion 31. Moreover, since the toughness (stickiness strength) is increased by the horizontal reinforcing portion 31 and the horizontal portion 22, even if a crack is generated, a rapid breakage of the beam 11 is suppressed.

  Further, if the imaginary line extending in the tangential direction from the edge of the through hole 12 and extending to the opening 19 is defined as the imaginary line CR2, both the annular reinforcing part 21 and the horizontal reinforcing part 31 intersect with the imaginary line CR2. It is preferable to arrange the reinforcing material 13 on the surface. In particular, the annular reinforcing portion 21 is preferably arranged so that the horizontal portion 22 intersects the virtual line CR2 to enhance toughness.

  In addition, since it is necessary to also make the height (length of the weight direction Z) of the annular reinforcement part 21 low if the beam length is made low with respect to the diameter of the through-hole 12, a horizontal part is provided at the upper end and the lower end of the annular reinforcement part 21. The provision of 22 is also advantageous in terms of downsizing the reinforcing material 13 in the gravity direction Z. On the other hand, both ends of the annular reinforcing portion 21 in the extending direction Y intersect with a crack virtual line extending in a tangential direction from the edge of the through hole 12 toward the outside of the opening portion 19 when the inclined portion 23 is elongated. The inclined portion 23 can be disposed at the position. Therefore, it is better not to provide portions extending in the gravity direction Z at both end portions in the extending direction Y of the annular reinforcing portion 21.

  As shown in FIGS. 2 and 3, a plurality of reinforcing members 13 may be arranged so as to be aligned in the axial direction X of the through hole 12. In the present embodiment, the horizontal reinforcing portion 31 is disposed on the inner side in the axial direction X than the annular reinforcing portion 21. Note that the numbers and arrangement order of the annular reinforcing portions 21 and the horizontal reinforcing portions 31 arranged in the axial direction X can be arbitrarily changed.

Next, the operation of the reinforcing member 13 and the reinforcing structure of the present embodiment will be described.
According to the reinforcing member 13 and the reinforcing structure of the present embodiment, cracks of the beam 11 due to the presence of the through hole 12 can be suppressed. Even if cracks occur around the through hole 12 in the beam 11, the toughness of the beam 11 is increased by the horizontal portion 22 and the horizontal reinforcing portion 31, so that it is possible to prevent abrupt destruction of the beam 11.

  And if reinforcement is carried out with the reinforcing material 13 in this way, the beam is made lower with respect to the through hole 12 so that the diameter ratio of the through hole 12 becomes larger than the recommended value (1/3 or less of the beam). Therefore, the cost can be reduced and the construction period can be shortened accordingly.

  In addition, by reinforcing the opening 19 with the reinforcing member 13, the number of the opening stirrups 17 can be reduced. Thereby, the effort which constructs the hole part rib 17 can be reduced.

According to the embodiment detailed above, the following effects are exhibited.
(1) The horizontal reinforcing portion 31 made of a steel plate can increase the cross-sectional area that effectively acts on the shear failure of the reinforcing member 13 in the portion where the through-hole 12 is provided in the beam 11. In the reinforced concrete beam 11 having the above, shear failure can be suppressed.

  (2) When the concrete enters the plurality of holes 32 provided in the horizontal reinforcing portion 31, the integrity of the horizontal reinforcing portion 31 that is a steel plate and the concrete constituting the beam 11 can be enhanced.

  (3) The annular reinforcing portion 21 disposed so as to surround the through hole 12 can suppress the occurrence of cracks around the through hole 12. Further, the horizontal reinforcing portion 31 extending in the extending direction Y can increase the cross-sectional area of the reinforcing member 13 that effectively acts on the shear failure. Therefore, in the reinforced concrete beam 11 having the through holes 12, the shearing is performed. Destruction can be suppressed.

  (4) Since the annular reinforcing portion 21 has the horizontal portion 22 extending in the extending direction Y, the shear failure can be effectively suppressed in the reinforced concrete beam 11 having the through hole 12.

(Example of change)
The embodiment described above can be modified and embodied as follows.
As in the first modification shown in FIG. 4, two or three or more holes 32 provided in the horizontal reinforcing portion 31 (31 </ b> B) constituting the reinforcing member 13 may be arranged vertically. In addition, the position and number of the holes 32 provided in the horizontal reinforcing portion 31 can be arbitrarily changed.

  As in the second modification shown in FIG. 5, the top edge and the bottom edge of the horizontal reinforcing portion 31 (31 </ b> C) constituting the reinforcing member 13 in the vicinity of the center in the extending direction Y including the opening portion 19 of the beam 11. You may provide the recessed part 33 in an edge. Thereby, the horizontal reinforcement part 31 can be reduced in weight.

-Like the 3rd modification shown in FIG. 6, the shape and arrangement | positioning of the hole 32 provided in the horizontal reinforcement part 31 (31D) which comprise the reinforcing material 13 can be changed arbitrarily.
As shown in FIGS. 6 and 7, in the third modified example, the protruding portion 34 that protrudes along the axial direction X by cutting and raising from the horizontal reinforcing portion 31 (31 </ b> D) extending in the extending direction Y and the gravity direction Z. May be provided. Thereby, while improving the integrity of the horizontal reinforcement part 31 and the concrete part 18, a yield strength can be improved.

  -Like the 4th modification shown in Drawing 8, shape reinforcements, such as H section steel or I section steel, may be sufficient as horizontal reinforcement part 31 (31E) which constitutes reinforcement material 13. Thereby, the horizontal reinforcement part 31 (31E) can exhibit higher proof stress with respect to stress, such as a tension | pulling, bending, and compression, than a steel plate.

  -Like the 5th modification shown in FIG. 9, the horizontal reinforcement part 31 (31F) which comprises the reinforcing material 13 may be channel steel. Thereby, the horizontal reinforcement part 31 (31F) can exhibit higher proof stress than a steel plate.

  As in the sixth modification shown in FIG. 10, the horizontal reinforcing portion 31 (31 </ b> G) constituting the reinforcing member 13 may be angle steel. Thereby, the horizontal reinforcement part 31 (31G) can exhibit higher proof stress than a steel plate.

  -Even if the shaft member 35 such as a reinforcing bar is inserted into a part or all of the hole 32 provided in the horizontal reinforcing portion 31 (31H) constituting the reinforcing member 13 as in the seventh modified example shown in FIG. Good. That is, the reinforcing member 13 and the reinforcing structure may include a shaft member 35 inserted through the hole 32. Thereby, while being able to improve the integrity of the horizontal reinforcement part 31 and the concrete part 18, the horizontal reinforcement part 31 can exhibit higher proof stress. Further, by inserting one shaft member 35 into the holes 32 of the plurality of horizontal reinforcing portions 31 arranged in the axial direction X, the plurality of horizontal reinforcing portions 31 arranged in the axial direction X are integrated, and higher strength is exhibited. be able to.

-You may weld the headed stud 36 to the horizontal reinforcement part 31 (31I) which comprises the reinforcing material 13, like the 8th modification shown in FIG.
As in the ninth modification shown in FIG. 13, a shaft member 35 such as a reinforcing bar is inserted into the hole 32 provided in the horizontal reinforcing portion 31 (31 I) constituting the reinforcing member 13, and both surfaces of the horizontal reinforcing portion 31 are attached. The two nuts 37 may be screwed into the shaft member 35 so as to be sandwiched, and the shaft member 35 may be fixed to the horizontal reinforcing portion 31 by the two nuts 37. Thereby, the shaft member 35 and the horizontal reinforcing portion 31 can be easily integrated.

  -As shown in FIGS. 11-13, the horizontal reinforcement part 31 and the cyclic | annular reinforcement part 21 which consist of steel materials do not need to be mutually connected. 11 to 13, three or more horizontal reinforcing portions 31 may be arranged in the axial direction X.

(Second Embodiment)
Next, a description will be given of a second embodiment of a reinforcing material and a reinforcing structure for a reinforced concrete beam having a through hole.

  In the second embodiment, components having the same reference numerals as those in the first embodiment have the same configuration as those in the first embodiment, and thus the description thereof will be omitted. In the following, description will be made focusing on differences from the first embodiment. Do.

  As shown in FIG. 14, the beam 11 of the present embodiment is different from the first embodiment in that the horizontal reinforcing portion 31 includes a horizontal reinforcing portion 31K. The horizontal reinforcing portion 31K of the present embodiment is made of a reinforcing bar that has a bent portion 38 in which both ends in the extending direction Y are bent in a hook shape, thereby increasing the adhesion to the concrete portion 18. In addition, the shape of the bending part 38 can be changed arbitrarily.

  The horizontal reinforcing portion 31K is disposed at a position closer to the upper end of the through hole 12 than the top end of the beam 11 in consideration of the length of the opening portion stirrup 17 in the gravity direction Z. Further, the bent portion 38 of the horizontal reinforcing portion 31K may be disposed at a position overlapping the through hole 12 in the gravity direction Z (between the upper end and the lower end of the through hole 12).

As shown in FIGS. 15 and 16, the horizontal reinforcing portion 31 </ b> K is disposed outside the annular reinforcing portion 21 in the axial direction X.
And according to 2nd Embodiment, the effect of said (3), (4) is exhibited.

(Example of change)
The second embodiment can be embodied with the following modifications.
-Like the 10th modification shown in Drawing 17, horizontal reinforcement part 31 (31L) which constitutes reinforcing material 13 may be an annular reinforcing bar.

  When the horizontal reinforcing portion 31 is a reinforcing bar, the reinforcing member 13 may be configured in an integrated state by bending the horizontal reinforcing portion 31 and the annular reinforcing portion 21 into one continuous reinforcing bar. In this case, since the reinforcing member 13 is made of a single member, it is possible to reduce the installation effort as compared with the case where the annular reinforcing portion 21 and the horizontal reinforcing portion 31 are made separately.

  As in the eleventh modification shown in FIG. 18, the horizontal reinforcing portion 31 (31 </ b> M) constituting the reinforcing member 13 may be formed by screwing nuts 37 in the vicinity of both ends of a linear reinforcing bar. Moreover, the horizontal reinforcement part 31 which comprises the reinforcing material 13 is a linear reinforcing bar, Comprising: You may not provide the nut 37 near both ends.

  For example, when the through hole 12 is disposed at a position close to either the top end or the lower end of the beam 11, the horizontal reinforcing portion 31 is disposed only on either the upper side or the lower side of the through hole 12. May be. Or the horizontal reinforcement part 31 of 1st Embodiment may be arrange | positioned to either one of the upper direction or the downward direction of the through-hole 12, and the horizontal reinforcement part 31 of 2nd Embodiment may be arrange | positioned to the other.

  When the steel plate or the steel plate is adopted as the horizontal reinforcing portion 31, the annular reinforcing portion 21 may not be provided. For example, instead of the annular reinforcing portion 21, cracking may be suppressed by combining the plurality of reinforcing bars around the through hole 12 to form the inclined portion 23.

  DESCRIPTION OF SYMBOLS 11 ... Beam, 12 ... Through-hole, 13 ... Reinforcement material, 14 ... Main reinforcement, 15 ... Set-up reinforcement, 16, 17 ... Stirrup, 18 ... Concrete part, 19 ... Opening part, 21 ... Annular reinforcement part, 22 ... Horizontal , 23 ... inclined part, 31 ... horizontal reinforcing part, 32 ... hole, 33 ... recess, 34 ... projection, 35 ... shaft material, 36 ... stud with head, 37 ... nut, 38 ... bent part, X ... axial direction , Y: extending direction, Z: gravity direction, CR1: imaginary line, CR2: imaginary line, SC: axis.

Claims (7)

Reinforcing material for reinforced concrete beams with through holes,
A horizontal reinforcing portion is disposed on at least one of the upper and lower sides of the through hole so that the extending direction of the beam is a longitudinal direction,
The horizontal reinforcing portion is made of a shape steel or a steel plate. The beam reinforcing member according to claim 1, wherein the horizontal reinforcing portion is provided with a plurality of holes. The beam reinforcing member according to claim 2, further comprising a shaft member inserted through the hole. A reinforcing material for reinforcing a reinforced concrete beam having a through hole,
A horizontal reinforcing portion extending in the extending direction of the beam;
An annular reinforcing portion disposed so as to surround the through hole;
A beam reinforcing material comprising: The said annular reinforcement part has a horizontal part extended in the said extending direction. The reinforcement material of the beam of Claim 4 characterized by the above-mentioned. A reinforcing structure of a reinforced concrete beam having a through hole,
A horizontal reinforcing portion is disposed on at least one of the upper and lower sides of the through hole so that the extending direction of the beam is a longitudinal direction,
The horizontal reinforcing portion is made of a shape steel or a steel plate. A reinforcing structure of a reinforced concrete beam having a through hole,
A horizontal reinforcing portion extending in the extending direction of the beam;
An annular reinforcing portion disposed so as to surround the through hole;
A reinforcing structure for a beam, comprising:

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