JP2016160721A - Reinforced-concrete perforated beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforced-concrete perforated beam much excellent in aspects of cost reduction and workability.SOLUTION: A reinforced-concrete perforated beam 2 having an open hole 3 forming an opening comprises: beam main reinforcements 9, 10A and 10B which are the reinforcements extending along the beam's span direction and which are arranged in the beam's width direction at predetermined intervals; and hoop reinforcements 8A and 8B and 8C stretched around the beam main reinforcements. The beam main reinforcements 10A and 10B are arranged below the open hole 3 and the beam main reinforcement 10B is arranged outside a region W of the beam in the beam width direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a reinforced concrete perforated beam.

As shown in Patent Document 1, a beam of a reinforced concrete building may be provided with piping, wiring, or a personal opening (through hole). Moreover, as shown in Patent Document 2, the underground beam may be provided with a slab at the top and a pressure platen at the bottom.
In addition, the beam which has the above through-holes is called a reinforced concrete perforated beam in this specification. Further, the term “reinforced concrete” described in the present specification includes steel reinforced concrete, and is used to include all structures in which concrete is reinforced with reinforcing bars.

5 and 6 show an example of a reinforced concrete perforated beam (hereinafter simply referred to as “beam”) according to the prior art, and FIG. 5 shows a state in which the beam is cut along a plane perpendicular to the span direction of the beam. Sectional drawing (schematic diagram), FIG. 6 is a plan view (schematic diagram) showing the relationship between beam main bars and pile main bars. In FIG. 5, hatching is omitted in order to avoid complication of the drawing.
5 and 6, reference numeral 100 indicates a floor slab, reference numeral 200 indicates a beam, and reference numeral 400 indicates a pressure platen. A through hole 300 is formed in the beam 200.

  In the floor slab 100, reference numeral 60 indicates a floor slab line extending in the span direction of the beam 200 (the front and back direction in FIG. 5). The floor slab reinforcement 60 is arranged at an appropriate interval in the width direction of the beam 200 (left and right direction in the drawing) in FIG. In addition, while extending in the width direction of the beam 200 (left and right direction in FIG. 5), there is also provided a floor slab bar 60 provided at an appropriate interval in the span direction of the beam 200. In FIG. Omitted.

  In the pressure platen 400, reference numeral 70 indicates a pressure plate rebar extending in the span direction of the beam 200. The pressure-resistant plate reinforcing bars 70 are arranged at appropriate intervals in the width direction of the beam 200 in FIG. In addition, although the pressure | voltage resistant bar reinforcement 70 extended in the width direction of the beam 200 and extended in the beam 200 span direction is also provided, the illustration is abbreviate | omitted in FIG.

  In the beam 200, reference numeral 90 indicates a beam main bar extending in the span direction of the beam 200. The beam main bars 90 are arranged at an appropriate interval in the width direction of the beam 200 in FIG. The beam main bar 90 is provided on the upper side and the lower side with respect to the through hole 300, and a hoop bar 80 is hung around the beam main bar 90 arranged vertically.

  In FIG. 6, the code | symbol 120 has shown the pile. The pile 120 supports the beam 200 at the intersection of the beam 200. In the pile 120, reference numeral 130 denotes a pile main reinforcement, and the tip of the pile main reinforcement 130 enters the beam 200 and intersects the beam main reinforcement 90.

JP 2014-122504 A JP 05-79044 A

  In the event of an earthquake, stress concentrates on the beam end where the beam 200 and the pressure platen 400 intersect, so damage is likely to occur. On the other hand, for example, if the blame of the beam 200 is increased, the amount of excavation will increase. Even if the width is increased to improve the structural performance, the construction cost is increased, which is not preferable.

  Moreover, in the site | part which supports the beam 200 with the pile 120, since the beam main reinforcement 90 and the pile main reinforcement 130 cross | intersect closely, construction becomes impossible, or workability falls even if construction is possible. Problems arise.

  Then, this invention is made | formed in view of such a condition, The objective is to provide the reinforced concrete perforated beam which was further excellent in the surface of cost and workability.

  A first aspect of the present invention for solving the above-mentioned problem is a reinforced concrete perforated beam having an opening, which is a reinforcing bar extending along the span direction of the beam and arranged at a predetermined interval in the width direction of the beam. A beam main bar, and a beam hoop bar hung around the beam main bar, the beam main bar being arranged on the upper side and the lower side with respect to the opening and the beam main bar arranged on the lower side At least a part of is arranged outside the region of the beam in the width direction.

  According to this aspect, in the reinforced concrete perforated beam having an opening, the beam main bars are arranged on the upper side and the lower side with respect to the opening, and at least a part of the beam main bars arranged on the lower side are arranged in the beam width direction. Therefore, it is possible to avoid overcrowding by widening the arrangement interval of the beam main bars, and to improve the workability.

  In addition, at least a part of the beam main bars arranged on the lower side is arranged outside the beam area in the width direction, and hoop bars are wound around the beam main bars. Therefore, the concrete reinforcement effect by the beam main bar and the hoop bar acts not only in the beam width region but also outside the beam width region, for example, at the part where the beam and the pressure plate intersect (particularly at the beam end and the lower part of the opening). The strength can be effectively increased.

  According to a second aspect of the present invention, in the first aspect, a pressure platen is formed on a lower side of the beam, and a beam main bar arranged outside the region of the beam is arranged in the pressure platen. It is characterized by that.

  According to this aspect, the pressure platen is formed in the lower part of the beam, and the beam main bars arranged outside the region of the beam are arranged in the pressure platen, so that the pressure platen is formed in the lower part of the beam. In the constructed structure, overcrowding can be avoided, and workability can be improved. In addition, it is possible to effectively increase the strength of the portion where the beam and the pressure platen intersect (particularly the beam end portion and the opening lower portion).

  According to a third aspect of the present invention, in the first aspect, a beam-shaped main bar arranged outside the region of the beam is formed with a base portion extending in the width direction below the beam. Are arranged in the platform.

  According to this aspect, the base part formed by extending in the width direction is formed in the lower part of the beam, and the main beam bars arranged outside the region of the beam are arranged in the base part. Therefore, in the configuration in which the base portion is formed in the lower part of the beam, it is possible to avoid overcrowding and to improve the workability.

  In addition, the accessibility to the opening formed in the beam is improved. That is, when the opening is formed as a through hole and the opening is at a high position, the inspector needs to access the opening using a ladder or a stand. However, since the trapezoidal portion is formed, the trapezoidal portion can be used as a lifting platform, and as a result, the accessibility to the opening can be improved.

According to a fourth aspect of the present invention, in the third aspect, the upper surface of the base portion is located at a position lower than a lower edge of the opening.
According to this aspect, since the upper surface of the trapezoidal portion is located at a position lower than the lower edge of the opening, the trapezoidal portion does not erode the opening and prevents a decrease in accessibility to the opening. be able to.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the lower part of the beam is supported by a pile, and is provided in the beam main bar and the pile arranged in the region of the beam in the width direction. It is characterized by the crossing of the main pile bars.

  According to this aspect, the lower part of the beam is supported by the pile, and the beam main bar disposed in the region of the beam in the width direction intersects with the pile main bar provided in the pile. According to the first aspect, Since overcrowding of the beam main bars is avoided, interference between the beam main bars and the pile main bars can be avoided. As a result, the workability can be improved.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, a reinforcing metal fitting is disposed around the opening.
According to this aspect, since the reinforcing metal fitting is arranged around the opening, it is possible to suppress cracks around the opening when an earthquake occurs. In addition, reinforcement for reinforcement is extremely easy.

  According to a seventh aspect of the present invention, in the sixth aspect, the reinforcing bracket includes a reinforcing bar extending in a direction of approximately 45 ° with respect to the span direction and the beam direction of the beam.

  According to this aspect, since the reinforcing metal fitting is provided with the reinforcing bar extending in a direction of approximately 45 ° with respect to the span direction and the beam ridge direction of the beam, it more reliably counters the shearing force applied to the opening. be able to.

Sectional drawing of the beam which concerns on one Embodiment of this invention. The front view of the beam which concerns on one Embodiment of this invention. The top view which shows the relationship between the beam reinforcement and the pile reinforcement of the beam which concerns on one Embodiment of this invention. Sectional drawing of the beam which concerns on other embodiment of this invention. Sectional drawing of the beam which concerns on a prior art. The top view which shows the relationship between the beam reinforcement and the pile reinforcement according to a prior art.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same structure in each figure, and the overlapping description will be avoided.
First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a beam 2 according to the first embodiment of the present invention, FIG. 2 is a front view of the beam 2, and FIG. 3 shows a relationship between beam main bars 10A and 10B of the beam 2 and a pile main bar 13 of the pile 12. It is a top view. FIG. 4 is a cross-sectional view of a beam 2A according to another embodiment of the present invention, which will be described later. Each figure is a schematic diagram, and hatching etc. are omitted in order to avoid complication of the drawing.

  1 and 2 show a reinforced concrete beam / floor structure. This reinforced concrete beam / floor structure includes a beam 2, a floor slab 1 formed on the upper portion of the beam 2, and a pressure-resistant panel 4 formed on the lower portion of the beam 2.

  In the floor slab 1, reference numeral 6 indicates a floor slab line extending in the span direction of the beam 2 (the front and back direction in FIG. 1 and the left and right direction in FIG. 2). The floor slab reinforcement 6 is arranged at an appropriate interval in the width direction of the beam 2 (left and right direction in the drawing) in FIG. The floor slab muscle 6 is configured in two stages in this embodiment. A floor slab bar 6 extending in the width direction of the beam 2 and provided at an appropriate interval in the span direction of the beam 2 is also provided, but is not shown in FIG.

  In the pressure plate 4, reference numeral 7 indicates a pressure plate reinforcing bar extending in the span direction of the beam 2. The pressure-resistant bar reinforcing bars 7 are arranged at an appropriate interval in the width direction of the beam 2 in FIG. In the present embodiment, the pressure-resistant bar reinforcement 7 is configured in two stages. In addition, although the pressure-resistant bar reinforcement 7 extended in the width direction of the beam 2 and extended in the span direction of the beam 2 is provided, the illustration is abbreviate | omitted in FIG.

  In the beam 2, reference numerals 9, 10 </ b> A, and 10 </ b> B indicate beam main bars extending in the span direction of the beam 2. The main beam bars 9, 10A, 10B are arranged at appropriate intervals in the width direction of the beam 2 in FIG. The beam main bars 9, 10A, 10B are configured in two stages in this embodiment. Among these, the upper stage of the beam main reinforcement 9 is located in the area | region of the floor slab 1 in the beam ridge direction (up-down direction of FIG.1 and FIG.2). Further, the main beam bars 10A and 10B are located in the region of the pressure-resistant platen 4 in the beam chamfer direction.

The beam main bar 9 is provided on the upper side with respect to the through hole 3, and a hoop bar 8 A is wound around the beam main bar 9. The main beam bars 10A and 10B are provided on the lower side with respect to the through hole 3, and a hoop bar 10A is hung around the main beam bar 10A. A hoop bar 8C is wound around the beam main bar 10B. In FIG. 2, reference numeral 8 </ b> D denotes a hoop line provided outside the region of the through hole 3 in the beam span direction.
A plurality of hoop muscles 8A, 8B, 8C, and 8D are arranged at appropriate intervals in the span direction of the beam 2 as shown in FIG.

  For the beam main bars 9, 10A and 10B, for example, reinforcing bars having a diameter of 25 to 41 mm can be used. Moreover, the floor slab reinforcement 6 and the pressure | voltage resistant board reinforcement 7 can use the reinforcing bar of diameter 10-19 mm, for example. That is, reinforcing bars having a diameter larger than that of the floor slab bar 6 and the pressure-resistant bar bar 7 are used for the main beam bars 9, 10A, 10B.

  In the beam 2, reference numeral 3 indicates a through-hole penetrating in the width direction of the beam 2, and openings are formed on both sides of the beam 2 in the width direction by the through-hole 3. A reinforcing metal fitting 5 is arranged around the through hole 3. The reinforcing metal fitting 5 is formed in an annular shape, and more specifically, a reinforcing bar extending in a direction of approximately 45 ° with respect to the span direction of the beam 2 (left-right direction in FIG. 2) and the beam ridge direction (up-down direction in FIG. 2). It is configured with.

In this way, the reinforcing metal fitting 5 is configured to include a reinforcing bar extending in a direction of approximately 45 ° with respect to the span direction and the beam stalk direction of the beam 2, and therefore, against the shearing force applied to the opening of the through hole 3. It can be countered more reliably. Further, by using such a reinforcing metal fitting 5, it is very easy to arrange reinforcing bars. However, the reinforcing metal fitting 5 can be omitted in the reinforced concrete beam / floor structure according to the present invention.
In addition, the reinforcing bar shown by the code | symbol 11 distribute | arranged to the upper and lower sides of the through-hole 3 is an opening reinforcement.

In FIG. 1, symbol D indicates a beam, symbol H indicates the diameter of the through hole 3, symbol F indicates a step between the pressure plate 4 and the through hole 3, and symbol E indicates the height of the pressure plate 4. It shows. Reference numeral W denotes an area occupied by the beam 2 in the width direction.
If the diameter H of the through-hole 3 exceeds 1/3 of the beam D and is 1/2 or less, the penetration depth can be suppressed, and a reinforced concrete beam / floor structure suitable for construction and cost is obtained. be able to.
For example, the diameter H of the through hole 3 can be set to 600 to 800 mm, and the beam length D can be set to 1200 to 1600 mm.
At this time, for example, the width W of the beam 2 can be set to 750 mm.

Further, for example, when the beam is D = 1200 mm and the through-hole diameter H = 600 mm, the height E of the pressure-resistant platen 4 can be set to 200 mm and the step F = 100 mm.
Alternatively, for example, in the case where the beam is D = 1600 mm and the through-hole diameter H = 800 mm, the height E of the pressure platen 4 can be 300 mm and the step F can be 100 mm.

  The reinforced concrete beam / floor structure having the above-described configuration can be constructed by, for example, placing concrete for the pressure platen 4, placing concrete for the beam 2, and then placing concrete for the floor slab reinforcement 1. .

A feature of the reinforced concrete beam / floor structure having the above-described configuration is the arrangement of the beam main bar 10B. That is, the main beam bars 10B arranged below the through hole 3 forming the opening are arranged outside the region W of the beam 2 in the width direction of the beam 2.
Thereby, an overcrowding arrangement | positioning can be avoided by expanding the arrangement | positioning space | interval of beam main reinforcement 10A, 10B, and the improvement of workability | operativity can be aimed at.

  For example, in FIG. 3, the code | symbol 12 has shown the pile. The pile 12 supports the beam 2 at the intersection of the beam 2. In the pile 12, the code | symbol 13 has shown the pile main reinforcement, the front-end | tip of the pile main reinforcement 13 enters the beam 2, and cross | intersects the beam main reinforcement 10A. Since the beam main reinforcement 10B is arranged outside the region of the beam 2, it does not intersect with the pile main reinforcement 13. That is, since the beam main bar 10B is arranged outside the region of the beam 2, it is possible to avoid overcrowding of the beam main bar, avoid interference between the beam main bar and the pile main bar 13, and ensure good workability. Can do.

For convenience of illustration, in FIG. 3 (and FIG. 6), the pile main bars 13 are not arranged at regular intervals along the outer periphery of the pile 12, but in actual construction, they are often arranged at regular intervals. The beam main bars 10A and 10B are arranged so as to avoid the pile main bars 13 arranged at equal intervals. Moreover, although the pile main reinforcement 13 is arrange | positioned near the outer periphery of the pile 12, you may arrange | position near the center of the pile 12. FIG.
In addition, when a pile diameter is 1500 mm, the pile main reinforcement 13 can use a reinforcing bar with a diameter of 38 mm, for example, and can make a number into about 24-36 pieces.

  Moreover, it is good also as a structure which provides a footing in the cross | intersection part of the beam 2, and the pile 12 supports a footing. In the case of such a configuration, interference between the pile main bars 13 and the footing main bars (not shown) can be avoided, and good workability can be ensured.

  A hoop bar 8C is hung around the beam main bar 10B. Therefore, the concrete reinforcement effect by the beam main bar 10B and the hoop bar 8C acts not only in the beam width region but also outside the beam width region, for example, a portion where the beam 2 and the pressure platen 4 intersect (particularly, the beam end portion and the penetration). It is possible to effectively increase the strength of the lower portion of the hole 3.

  As described above, by arranging the beam main reinforcing bars 10B outside the beam width region, it is possible to avoid overcrowding and to ensure good workability. In addition, in the said embodiment, although the beam main reinforcement 10B was arrange | positioned in the pressure | voltage resistant board 4 outside a beam width area | region, this invention is not limited to such an embodiment.

For example, as shown in FIG. 4, the beam main reinforcing bars 10 </ b> B may be arranged on a platform portion 14 that extends in the beam width direction at the lower part of the beam 2.
In this way, in the configuration in which the lower portion of the beam 2 is integrated with the base portion 14, overcrowding can be avoided, and workability can be improved.

In addition, the accessibility to the through hole 3 formed in the beam 2 is improved. That is, when the through hole 3 is formed as a human through hole and the lower edge 3a of the through hole 3 is at a high position, the inspector accesses the through hole 3 using a ladder or a stand. There is a need to. However, since the trapezoidal portion 14 is formed, the trapezoidal portion 14 can be used as a lifting platform, and as a result, the accessibility to the through hole 3 can be improved.
The trapezoidal portion 14 may be formed over the entire span direction of the beam 2 or may be formed only in a predetermined range including the lower side of the through hole 3.

  In the present embodiment, the upper surface 14 a of the base portion 14 is at a position lower than the lower edge 3 a of the through hole 3. Thereby, the base-like part 14 does not erode the through-hole 3 and can prevent the accessibility to the through-hole 3 from being lowered. However, the upper surface 14a of the base portion 14 and the lower edge 3a of the through hole 3 can be set to the same height.

  Moreover, although the trapezoidal part 14 is formed in one step in this embodiment, when the level | step difference between the upper surface 14a of the trapezoidal part 14 and the lower edge 3a of the through-hole 3 is large, for example, trapezoidal It is also possible to form a step between the upper surface 14a of the portion 14 and the lower edge 3a of the through hole 3.

DESCRIPTION OF SYMBOLS 1 Floor slab 2 Reinforced concrete perforated beam 3 Through-hole 4 Pressure-resistant board 5 Reinforcement metal fitting 6 Floor slab reinforcement 7 Pressure-resistant board reinforcement 8A, 8B, 8C Hoop reinforcement 9 Beam main reinforcement 10A, 10B Beam reinforcement 11 Opening reinforcement 12 Pile 13 Pile main reinforcement 14 Trapezoid

Claims (7)

A reinforced concrete perforated beam with an opening,
A reinforcing bar extending along the span direction of the beam, which is arranged at a predetermined interval in the width direction of the beam;
A beam hoop line hung around the beam main bar,
The beam main bars are arranged on the upper side and the lower side with respect to the opening, and at least a part of the beam main bars arranged on the lower side are arranged outside the beam region in the width direction.
Reinforced concrete perforated beam. In the reinforced concrete perforated beam according to claim 1, a pressure platen is formed under the beam,
Beam main bars arranged outside the beam area are arranged in the pressure platen,
Reinforced concrete perforated beam. In the reinforced concrete perforated beam according to claim 1, a trapezoidal portion extending in the width direction is formed on the lower side of the beam,
The main beam bars arranged outside the beam area are arranged in the platform.
Reinforced concrete perforated beam. In the reinforced concrete perforated beam according to claim 3, the upper surface of the trapezoidal portion is at a position lower than the lower edge of the opening.
Reinforced concrete perforated beam. In the reinforced concrete perforated beam according to any one of claims 1 to 4, a lower portion of the beam is supported by a pile,
The beam main bars arranged in the region of the beam in the width direction intersect with the pile main bars provided in the pile,
Reinforced concrete perforated beam. In the reinforced concrete perforated beam according to any one of claims 1 to 5, a reinforcing metal fitting is disposed around the opening.
Reinforced concrete perforated beam. The reinforced concrete perforated beam according to claim 6, wherein the reinforcing bracket includes a reinforcing bar extending in a direction of approximately 45 ° with respect to the span direction and the beam direction of the beam.
Reinforced concrete perforated beam.

Images