Beam structure, support member for beam reinforcement, and beam reinforcement method

Abstract

To accurately and easily position and support a beam main reinforcement with respect to a steel frame, to improve workability of reinforcement arrangement work, and to drastically reduce a working time required for beam construction.SOLUTION: A beam structure comprises: a steel frame 50 spanning between opposed columns; a plurality of beam main reinforcements 14 arranged above the steel frame 50 and extending along the longitudinal direction of the steel frame 50; concrete covering the steel frame 50 and the plurality of beam main reinforcements 14; and a support member 20 on top of the steel frame 50 that supports the plurality of beam main reinforcements 14 from below. In the case of a hybrid beam in which a central part of the steel frame 50 is a steel beam part and both ends are reinforced concrete beam parts, the support member 20 is provided at an end part on the steel frame beam part side of the steel frame 50 in the reinforced concrete beam part.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a beam structure, a support member for beam main reinforcing bars, and a method for arranging beam main reinforcing bars. [Background technology]

[0002] In recent years, composite beams (hereafter referred to as hybrid beams) made of reinforced concrete (RC) and steel (S) have been adopted as the beam framework of buildings to increase the span of parts or all of the buildings. This type of composite beam is made by connecting a steel frame covered with reinforced concrete at both ends between columns of reinforced concrete or other structures. Hereafter, the central section of the hybrid beam, which is made of steel, will be referred to as the steel beam section, and both ends covered with reinforced concrete will be referred to as the reinforced concrete beam section (RC beam section). In the reinforced concrete beam section of a hybrid beam, generally, multiple main beam bars and multiple transverse reinforcement bars surrounding the multiple main beam bars and the steel frame are arranged and embedded throughout the entire reinforced concrete beam section. This horizontal reinforcement also includes concentrated reinforcement bars with denser reinforcement at the column side end of the reinforced concrete beam section and the steel beam side end. Hybrid beams are attracting attention as a new construction method that allows for buildings to be constructed with long span beams because the beam's weight is reduced as the central section is made of steel and the beam depth is reduced. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-190102 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, when multiple beam main bars are arranged above the steel frame, there are no components supporting the multiple beam main bars at a distance above the steel frame at the end of the reinforced concrete beam section on the steel beam section side, making it difficult to position the beam main bars at the desired position relative to the steel frame and requiring separate fixing components for the beam main bars, increasing the number of steps in the reinforcement work. The present invention has been made in consideration of the above circumstances, and has an object to provide a beam structure that allows the beam main reinforcement to be accurately and easily positioned relative to a steel frame, and a support member for beam main reinforcement arrangement. Another object of the present invention is to provide a method for arranging main beam reinforcement bars that can improve the workability of the reinforcement work. [Means for solving the problem]

[0005] In order to achieve the above-mentioned object, the present invention is characterized in comprising a steel frame spanning between opposing columns, a plurality of main beam reinforcements arranged above the steel frame and extending along the longitudinal direction of the steel frame, concrete covering the steel frame and the plurality of main beam reinforcements, and a support member on the upper part of the steel frame that supports the plurality of main beam reinforcements from below. The present invention is also characterized in that the support member comprises a base having a vertical length and attached to the upper surface of the steel frame, and a beam main reinforcement support portion provided at the base and supporting the multiple beam main reinforcements. The present invention is also characterized in that the beam main reinforcement support portion comprises an elongated member provided at the base portion and extending above the steel frame in a direction intersecting the longitudinal direction of the steel frame, and a positioning portion provided on the elongated member for positioning the multiple beam main reinforcements in the beam width direction of the steel frame. In addition, the present invention is characterized in that the beam is a hybrid beam in which the central portion of the steel frame is a steel beam section and both ends are reinforced concrete beam sections, and the support member is provided at the end of the steel frame on the steel beam section side of the reinforced concrete beam section. The present invention also provides a support member that supports from below a plurality of main beam reinforcements arranged above a steel frame that constitutes a beam, the support member comprising a base having a length in the vertical direction and attached to the upper surface of the steel frame, and a beam main reinforcement support portion that is provided at the base and supports the plurality of main beam reinforcements. The present invention is also characterized in that the beam main reinforcement support portion comprises an elongated member provided at the base portion and extending above the steel frame in a direction intersecting the longitudinal direction of the steel frame, and a positioning portion provided on the elongated member for positioning the multiple beam main reinforcements in the beam width direction of the steel frame. In the present invention, the base is removably attached to the upper surface of the steel frame. The present invention is also characterized in that a support member for beam main reinforcement arrangement, which includes a base attached to a steel frame constituting a beam and a beam main reinforcement support portion provided at the base and supporting a plurality of beam main reinforcements above the steel frame, is attached to the upper surface of the steel frame, the plurality of beam main reinforcements are supported on the upper surface of the beam main reinforcement support portion while being positioned in the beam width direction of the steel frame, transverse reinforcement is arranged to surround the steel frame, the support member, and the plurality of beam main reinforcements, the transverse reinforcement is used to arrange the plurality of beam main reinforcements below the steel frame, and concrete is poured so as to embed the steel frame, the plurality of beam main reinforcements, and the transverse reinforcement. The present invention is also characterized in that the base of the support member is removably attached to the upper surface of the steel frame, and after the transverse reinforcement is arranged, the multiple main beam reinforcements arranged above the steel frame are fixed to the transverse reinforcement using fixing members, and after the support member is removed from the steel frame, the concrete is poured. Effect of the Invention

[0006] According to the beam structure, support member for beam main reinforcement, and beam main reinforcement arrangement method of the present invention, the upper part of the steel frame is provided with a support member that supports multiple beam main reinforcements from below. Therefore, when arranging multiple beam main reinforcements above the steel frame, the beam main reinforcements can be accurately and easily positioned and supported relative to the steel frame, which is advantageous in improving the workability of the reinforcement arrangement work and significantly shortening the work time required for beam construction. In addition, even if the reinforcing bars are arranged in a crowded manner inside the beam, multiple main beam bars are reliably supported by the support members, which is advantageous in that it makes it possible to arrange the reinforcing bars easily and quickly even in a crowded area. Furthermore, if the support member is composed of a base that has a vertical length and is attached to the upper surface of the steel frame, and a beam main reinforcement support part that is provided at the base and supports multiple beam main reinforcements, the support member will be composed only of parts that have the parts necessary to support the beam main reinforcements, which is advantageous in preventing an increase in the weight of the beam and reducing its weight. Furthermore, if the beam main reinforcement support section is composed of an elongated member provided at the base and extending above the steel frame in a direction intersecting the longitudinal direction of the steel frame, and a positioning section provided on the elongated member and positioning multiple beam main reinforcements in the beam width direction of the steel frame, the simple configuration makes it possible to more accurately and easily position the multiple beam main reinforcements relative to the steel frame. In addition, in the present invention, if the support members are removably attached to the steel frame, the support members can be reused by removing them before pouring the concrete, which is advantageous in terms of reducing costs. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram of a hybrid beam. [Diagram 2] FIG. 2 is a side view of the reinforced concrete beam of the first embodiment. [Diagram 3] 3A is a cross-sectional view of the reinforced concrete beam part of the first embodiment taken along line AA in FIG. 1, and FIG. 3B is a cross-sectional view of the reinforced concrete beam part of the first embodiment taken along line BB in FIG. 3A. [Figure 4] FIG. 2A is a perspective view of a support member according to the first embodiment, and FIGS. 2B and 2C are perspective views of other support members. [Diagram 5] FIG. 11 is a perspective view of a support member according to a second embodiment. [Figure 6] FIG. 13 is a perspective view of a support member according to a third embodiment. [Figure 7] FIG. 13 is a perspective view of a support member according to a fourth embodiment. [Figure 8]FIG. 13 is a perspective view of a support member coupled to a steel frame in the fifth embodiment. [Figure 9] FIG. 13 is a side view of a support member according to the sixth embodiment. [Figure 10] FIG. 23 is an explanatory diagram of a case where a support member according to the sixth embodiment is disassembled. [Figure 11] 13(A), (B), and (C) are explanatory views showing the procedure of a method for installing a support member according to a sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (First embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, referring to FIG. 1, a typical hybrid beam 10 to which the present invention is applicable will be described. The hybrid beam 10 has a structure in which both ends of a steel frame 50 such as an I-beam or H-beam that is spanned between opposing columns 12 are covered with reinforced concrete. As shown in FIG. 2, and FIGS. 3(A) and (B), the steel frame 50 of this embodiment is an I-beam made up of a web 5002, an upper flange 5004, and a lower flange 5006. The center of the steel frame 50 is a steel beam section 10A, and both ends are reinforced concrete beam sections 10B, the steel frame 50 has an inside span, the ends of the steel frame 50 are located in contact with the side of the column 12, but do not penetrate into the column 12, and reference numeral 11A in Fig. 1 indicates a stud bolt, and reference numeral 11B indicates a floor slab. Note that the ends of the steel frame 50 may be located in the vicinity of the side of the column 12.

[0009] The reinforced concrete beam section 10B is made of cast-in-place concrete. The concrete may be either ordinary concrete or fiber-reinforced concrete. The reinforced concrete beam section 10B is reinforced by a plurality of main beam reinforcements 14 arranged above and below the steel frame 50 and extending along the longitudinal direction of the steel frame 50, and a plurality of transverse reinforcements 16 surrounding these main beam reinforcements 14, and the main beam reinforcements 14 are fixed to the column-beam joints by means of fixing hardware or bent fixing. In addition, at the end portion on the column-beam joint side of the reinforced concrete beam section 10B and the portion corresponding to the end portion on the steel beam section 10A side, the horizontal reinforcement bars 16 are particularly densely arranged as concentrated reinforcement bars 16A. As the horizontal reinforcement 16, welded closed type reinforcement, hooked reinforcement, spiral reinforcement, etc. can be appropriately used. Note that, as the concentrated reinforcement 16A, it is preferable to use welded closed type reinforcement made of high strength steel bars, since it is possible to increase the strength at the end of the hybrid beam. In addition, in the reinforced concrete beam section 10B, a steel frame 50, a plurality of main beam reinforcements 14, a plurality of lateral reinforcements 16, and concrete 18 filling the gaps between the support members 20 are provided. In this way, by providing concentrated reinforcement bars 16A at the parts corresponding to the end of the reinforced concrete beam section 10B on the column 12 side and the end of the steel beam section 10A side, stress is transmitted from the steel frame 50 to the reinforced concrete beam section 10B.

[0010] As shown in Figures 2, 3(A) and (B), in the reinforced concrete beam section 10B, a support member 20 that supports multiple beam main reinforcements 14 from below is provided on the upper part of the upper flange 5004 of the steel frame 50 on the steel beam section 10A side. In order to make it easier to see the main parts of the present invention in FIG. 2, multiple beam main reinforcements 14, lateral reinforcements 16, and concentrated reinforcements 16A are drawn with solid lines, and the steel frame 50 and support members 20 are drawn with dashed lines. As shown in Figure 4 (A), the support member 20 is composed of a base 22 having a vertical length and attached to the upper surface of the upper flange 5004 of the steel frame 50, and a beam main reinforcement support portion 24 provided on the base 22 and supporting multiple beam main reinforcements 14. In this embodiment, the base 22 and the beam main reinforcement support part 24 are each composed of a rectangular plate-shaped member, and the base 22 protrudes downward from the underside of the longitudinal center of the beam main reinforcement support part 24, and the base 22 and the beam main reinforcement support part 24 are perpendicular to each other. Here, the support member 20 may be constructed using a rectangular plate that contacts the upper flange 5004, but if it is constructed as in the support member 20 of this embodiment, it can be constructed using only parts that have the necessary parts, which is advantageous in preventing an increase in the weight of the beam and achieving weight reduction.

[0011] The lower part of the base 22 is joined to the upper surface of the upper flange 5004 of the steel frame 50 at the center in the width direction of the upper flange 5004 by welding or bolts. As a result, the beam main reinforcement support portion 24 is composed of an elongated member extending at a location above the steel frame 50 in a direction intersecting the longitudinal direction of the steel frame 50, in this embodiment in a direction perpendicular to the longitudinal direction of the steel frame 50 (the beam width direction of the steel frame 50). In other words, the rectangular plate-shaped member constituting the beam main reinforcement support portion 24 is composed of an elongated member having a width Y along the longitudinal direction of the steel frame 50 and a length X that is greater than the beam width direction of the steel frame 50. When the base 22 is welded to the steel frame 50, the base 22 is made of steel, but the beam main reinforcement support portion 24 may be made of either steel or synthetic resin. When the base 22 is connected to the steel frame 50 by bolts, the base 22 and the beam main bar support portion 24 may be made of either steel or synthetic resin.

[0012] Here, as shown in FIG. 4(B), the support member 20 may be attached to the steel frame 50 by inserting the base 22 between two plate-shaped auxiliary members 40A, 40B arranged parallel to each other on the upper surface of the upper flange 5004 of the steel frame 50. Also, as shown in FIG. 4(C), the support member 20 may be configured to have two bases 22A, 22B protruding parallel to each other from the underside of the beam main reinforcement support portion 24, and an auxiliary member 40 erected on the upper surface of the upper flange 5004 of the steel frame 50 may be inserted between the two bases 22A, 22B to attach the support member 20 to the steel frame 50. 4(B)(C), the bases 22, 22A, 22B of the support member 20 and the auxiliary members 40A, 40B, 40 erected on the upper surface of the upper flange 5004 of the steel frame 50 may be installed simply by inserting them into each other, without welding or bolting. In this case, the support member 20 can be easily removed and reused. In addition, in the case of the configuration shown in Figures 4(B) and (C), the base 22, 22A, 22B of the support member 20 and the auxiliary members 40A, 40B, 40 erected on the upper surface of the upper flange 5004 of the steel frame 50 may be joined to each other by welding, bolts, etc. Specifically, for example, when joining with bolts in the configuration shown in Fig. 4(B), base 22 is inserted between two plate-like auxiliary members 40A, 40B erected parallel to each other on the upper surface of upper flange 5004 of steel frame 50, and a bolt (not shown) is inserted from a bolt insertion hole provided in one of the auxiliary members to a bolt insertion hole in base 22 and screwed into a female thread provided in the other auxiliary member, joining support member 20 to steel frame 50. The same applies when joining with bolts in the configuration shown in Fig. 4(C).

[0013] In this manner, when the base 22 is connected to the steel frame 50 with bolts, the support member 20 can be removed from the steel frame 50 by removing the bolts. Therefore, after the main beam reinforcement 14 has been placed, the support member 20 can be removed before pouring concrete. The removed support members 20 can be attached to other steel frames and reused, which is advantageous in reducing the number of support members 20 and cutting costs. Furthermore, if the support member 20 is not removed from the steel frame 50 but is instead embedded in the hybrid beam 10, it is more advantageous to use a synthetic resin material than a steel material in order to reduce the weight of the hybrid beam 10.

[0014] Furthermore, by arranging multiple beam main reinforcements 14 at desired positions (for example, positions that have been marked out in advance) on the upper surface of beam main reinforcement support portion 24 and fixing them to beam main reinforcement support portion 24 with fixing members such as tie wires, they can be accurately and easily positioned and supported above the steel frame 50. Here, the fixing member refers to various conventionally known fasteners for fixing reinforcing bars, such as binding wires and wires, and in this embodiment, a configuration using binding wires will be described.

[0015] In this embodiment, as shown in Figures 2 and 3(B), a support member 20 that supports multiple beam main reinforcements 14 from below is provided on the upper part of the upper flange 5004 on the steel beam section 10A side of the steel frame 50, but a support member 20 that supports multiple beam main reinforcements 14 from below may also be provided on the upper part of the upper flange 5004 on the column 12 side.

[0016] Next, a conventional method for arranging beam main reinforcement and transverse reinforcement will be described. First, the steel frame is placed on the steel frame support, and then multiple beam reinforcement bars are positioned above the steel frame as follows: On the column side of the reinforced concrete beam, multiple beam reinforcements are placed on tie bars arranged in the column, and the beam reinforcements are fixed to the tie bars using tie wires or the like to determine their position. On the other hand, on the steel beam side, a plurality of beam main reinforcements are suspended and fixed to separately provided beam main reinforcement fixing members using cable ties or the like, and positioned above the steel beam. Then, after multiple main beam reinforcements are arranged above the steel frame, multiple transverse reinforcements are arranged using the multiple main beam reinforcements, and then multiple main beam reinforcements are arranged below the steel frame using the multiple transverse reinforcements.

[0017] In contrast, in the present embodiment, by using support members 20 to arrange multiple beam main reinforcements 14, it is not necessary to perform the task of suspending and fixing multiple beam main reinforcements 14 to a separately provided beam main reinforcement fixing member using cable ties or the like at the end portion on the steel beam section 10A side without support from below, and positioning them above the steel beam. As a result, even if the reinforcing bars are arranged in a crowded manner inside the beam, if a plurality of beam main reinforcements 14 are supported by the supporting members 20, it is advantageous in that construction can be easily performed in a short time even in the crowded reinforcing bars.

[0018] Next, a method of constructing the reinforced concrete beam portion 10B of the hybrid beam 10 of this embodiment will be described. First, the steel frame 50 is placed on a steel frame support material (not shown), and the support member 20 is attached to the steel frame 50 by welding or bolting the base 22 of the support member 20 to the upper surface of the upper flange 5004 in the area that will later become the end portion of the steel beam portion 10A of the steel frame 50.

[0019] Then, a plurality of beam main reinforcements 14 are arranged above the steel frame 50, and the positions of the plurality of beam main reinforcements 14 are determined above the steel frame 50. Specifically, the regions of the multiple beam main reinforcements 14 that will later become the ends on the steel beam section 10A side are supported from below by the upper surface of the beam main reinforcement support section 24 of the support member 20, and the ends of the multiple beam main reinforcements 14 on the column 12 side are placed on tie bars (not shown) arranged in the column 12. Next, the multiple beam main reinforcements 14 are adjusted to the desired positions, and the ends on the steel beam section 10A side are tied and fixed to the beam main reinforcement support section 24 with a tie wire or the like, and the ends on the column 12 side are tied and fixed to the tie bars. In addition, the ends of the multiple beam main reinforcements 14 on the column 12 side may be tied and fixed to any component that constitutes the column 12, not just to tie reinforcements, or may be extended and bent downward into the column 12. Furthermore, without being limited to the above process, the end portions of the multiple beam main reinforcements 14 on the column 12 side may be placed on tie bars (not shown) arranged in the column 12, and then the area of ​​the multiple beam main reinforcements 14 that will later become the end portions on the steel beam section 10A side may be placed on the upper surface of the beam main reinforcement support section 24 of the support member 20.

[0020] Next, the horizontal reinforcement bars 16 are temporarily placed on the multiple main beam reinforcements 14 arranged above the steel frame 50, and then a lower formwork (not shown), which is a lower concrete formwork used when pouring concrete, is installed below the horizontal reinforcement bars 16. A spacer (not shown) made of synthetic resin or steel is placed on the upper surface of the installed lower formwork to maintain a distance from the horizontal reinforcing bars 16.

[0021] Next, a plurality of beam main reinforcements 14 are arranged below the steel frame 50, above the horizontal reinforcement bars 16 and above the spacer, and the positioning of the plurality of beam main reinforcements 14 is determined below the steel frame 50. Specifically, the areas of the multiple main beam reinforcements 14 that will later become the ends on the steel beam section 10A side are placed on the transverse reinforcement bars 16 located below the steel frame 50 and supported from below by the transverse reinforcement bars 16, and the ends of the multiple main beam reinforcements 14 on the column 12 side are placed on tie bars (not shown) arranged in the column 12. In addition, without being limited to the above process, the end portions of the multiple beam main reinforcements 14 on the column 12 side may be placed on tie bars (not shown) arranged in the column 12, and then the area of ​​the multiple beam main reinforcements 14 that will later become the end portions on the steel beam section 10A side may be placed on the horizontal reinforcement bars 16 located below the steel frame 50. Then, a plurality of horizontal reinforcement bars 16 are rearranged at predetermined intervals so as to surround the steel frame 50, the support member 20, and the plurality of main beam reinforcements 14 above and below the steel frame 50.

[0022] Next, the multiple main beam reinforcements 14 above the steel frame 50 and the upper transverse reinforcements 16 are tied and fixed together with a tie wire or the like, and the multiple main beam reinforcements 14 below the steel frame 50 and the lower transverse reinforcements 16 are tied and fixed together with a tie wire or the like. This fixation connects the upper beam main bars 14 of the steel frame 50 with the lower beam main bars 14 and the horizontal reinforcement bars 16 to form a reinforcing bar assembly, which is less likely to deform due to the connections and can maintain its shape.

[0023] Then, left and right formwork (not shown) for concrete are placed on the left and right sides of the horizontal reinforcement bars 16. Concrete is filled into a concrete formwork consisting of a bottom formwork and left and right side formwork, and the concrete is poured so as to embed the steel frame 50, the support members 20, the multiple main beam reinforcements 14 arranged above and below the steel frame 50, and the transverse reinforcements 16. Once the concrete has hardened, the concrete formwork is removed and the hybrid beam 10 is completed.

[0024] In the above-described construction method, after the upper beam main reinforcement 14 of the steel frame 50 is arranged, the lower formwork and spacers are installed in that order, and after the lower beam main reinforcement 14 is tied to the horizontal reinforcement 16, the formwork on the left and right sides is installed; however, the timing of installing the concrete formwork and spacers can be changed as appropriate. That is, for example, the lower formwork and spacers may be installed together with the left and right side formworks. In addition, in the above description, when tying the beam main reinforcement bars 14 and the transverse reinforcement bars 16 together, the upper beam main reinforcement bars 14 of the steel frame 50 are first tied to the transverse reinforcement bars 16, and then the lower beam main reinforcement bars 14 are tied to the transverse reinforcement bars 16 to secure them in place. However, the reverse procedure may be used, that is, the lower beam main reinforcement bars 14 of the steel frame 50 are first tied to the transverse reinforcement bars 16, and then the upper beam main reinforcement bars 14 are tied to the transverse reinforcement bars 16 to secure them in place.

[0025] Here, a case where the support member 20 is removably attached to the steel frame 50 will be described. As described above, by tying and fixing the upper multiple beam main reinforcements 14 and the upper transverse reinforcements 16 of the steel frame 50, and tying and fixing the lower multiple beam main reinforcements 14 and the lower transverse reinforcements 16, a steel bar assembly consisting of the upper beam main reinforcements 14, the lower beam main reinforcements 14, and the transverse reinforcements 16 is created. A spacer (not shown) made of synthetic resin or steel is placed on the upper surface of the installed lower formwork to maintain a distance from the horizontal reinforcing bars 16. Therefore, by subsequently releasing the connection between the beam main reinforcement support part 24 and the multiple beam main reinforcements 14 above the steel frame 50, the support member 20 can be removed while maintaining the shape of the upper and lower beam main reinforcements 14 and the horizontal reinforcement bars 16. If the support member 20 is removed before pouring concrete, it can be reused.

[0026] In this way, in the first embodiment, a support member 20 that supports a plurality of beam main reinforcements 14 from below is provided at the upper part of the end part of the steel frame 50 on the steel beam section 10A side. Therefore, when arranging the plurality of beam main reinforcements 14 above the steel frame 50, the plurality of beam main reinforcements 14 can be accurately and easily positioned and supported relative to the steel frame 50, which is advantageous in improving the workability of the reinforcement work and significantly shortening the work time required for beam construction. In addition, even if the reinforcing bars are arranged in a crowded manner inside the beam, the multiple beam main reinforcements 14 are securely supported by the support members 14, which is advantageous in that the reinforcement bars can be arranged easily and quickly even in crowded areas. In addition, since the support member 22 is simply constructed of the base portion 22 and the beam main reinforcement support portion 24, it is advantageous in suppressing an increase in the weight of the beam and achieving weight reduction. Furthermore, if the support members 22 are provided so as to be removable from the steel frame 50, they can be removed before pouring concrete and attached to other steel frames 50 for reuse, which reduces the number of support members 22 to be prepared and is advantageous in terms of cutting costs.

[0027] (Second embodiment) In the first embodiment, the upper surface of the beam main reinforcement support portion 24 of the support member 22 is flat, whereas in the second embodiment, a recess is provided on the upper surface of the beam main reinforcement support portion as a positioning portion for positioning multiple beam main reinforcements in the width direction of the steel beam. In the following description of the embodiment, the same parts and members as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and the description will focus on the parts that are different from the first embodiment.

[0028] As shown in FIG. 5, the support member 20 is composed of a base portion 22 attached to a steel frame 50 and a beam main bar support portion 26 provided on the base portion 22 and supporting a plurality of beam main bars 14 . The configuration of the base portion 22 is similar to that of the first embodiment.

[0029] The beam main reinforcement support part 26 is provided on the base 22 and is configured to include an elongated member 2602 extending above the steel frame 50 in the beam width direction of the steel frame 50 (the α direction in Figure 5), and a plurality of recesses 2604 provided in the elongated member 2602 as positioning parts for positioning a plurality of beam main reinforcements 14 in the α direction. A plurality of recesses 2604 are provided on the upper surface of the elongated member 2602 at predetermined intervals in the α direction, and a plurality of beam main reinforcements 14 are housed therein so as to be immovable in the α direction. The number of recesses 2604 is the same as the number of beam main reinforcements 14 to be arranged. The recess 2604 in this embodiment is formed with a cylindrical surface, but may be any shape, such as a triangular or rectangular cross section, that allows the beam main reinforcement 14 to be engaged. By accommodating and arranging multiple beam main reinforcements 14 in recesses 2604 provided on the upper surface of the beam main reinforcement support part 26 and fixing them to the beam main reinforcement support part 26 with tie wires, the multiple beam main reinforcements 14 can be more accurately and easily positioned and supported relative to the steel frame 50.

[0030] According to the support member 20 of the second embodiment, a plurality of recesses 2604 are provided on the upper surface of the elongated member 2602 of the beam main reinforcement support portion 26 in the beam width direction of the steel frame 50. Therefore, in addition to the effects of the first embodiment, the simple configuration makes it possible to more accurately and easily position and support a plurality of beam main reinforcements 14 relative to the steel frame 50, which is advantageous in improving the workability of the reinforcement work and further shortening the work time required for beam construction. In addition, the recess 2604 reduces the volume of the support member 20, which is advantageous in terms of reducing the weight of the support member 20.

[0031] (Third embodiment) In the second embodiment, multiple recesses 2604 are provided on the upper surface of the elongated member 2602 of the beam main reinforcement support part 26, whereas in the third embodiment, a protrusion is provided on the upper surface of the elongated member as a positioning part for positioning in the width direction of the steel beam. As shown in FIG. 6, the support member 20 is composed of a base portion 22 attached to a steel frame 50 and beam main bar support portions 28 that are provided on the base portion 22 and support a plurality of beam main bars 14 . The beam main reinforcement support part 28 is provided on the base 22 and is configured to include an elongated member 2802 extending above the steel frame 50 in the beam width direction of the steel frame 50 (the α direction in Figure 6), and a plurality of protrusions 2804 provided on the elongated member 2802 as positioning parts for positioning a plurality of beam main reinforcements 14 in the α direction. A plurality of protrusions 2804 are provided on the upper surface of the elongated member 2802 at predetermined intervals in the α direction, and a plurality of beam main reinforcements 14 are locked between them so as to be immovable in the α direction. In other words, a plurality of beam main reinforcements 14 are retained by being fitted between two protrusions 2804, and the number of protrusions 2804 is twice the number of beam main reinforcements 14 to be arranged. The projection 2804 in this embodiment has a cross section shaped like a part of an ellipse with a curved line, but it may have a cross section of any shape, such as a triangle or rectangle, that can engage the beam main reinforcement 14. By arranging multiple beam main reinforcements 14 between protrusions 2804 provided on the upper surface of the beam main reinforcement support portion 28 and fixing them to the transverse reinforcement bars 16 with tie wires, the multiple beam main reinforcements 14 can be more accurately and easily positioned and supported relative to the steel frame 50.

[0032] According to the support member 20 of the third embodiment, a plurality of protrusions 2804 are provided on the upper surface of the elongated member 2802 of the beam main reinforcement support portion 28 in the beam width direction of the steel frame 50. Therefore, in addition to the effects of the first embodiment, the simple configuration makes it possible to more accurately and easily position and support a plurality of beam main reinforcements 14 relative to the steel frame 50, which is advantageous in improving the workability of the reinforcement work and further shortening the work time required for beam construction.

[0033] (Fourth embodiment) In the first embodiment, the base 22 of the support member 22 is rectangular plate-shaped, whereas in the fourth embodiment, the base is configured by combining two rectangular plate-shaped members. As shown in FIG. 7, the support member 20 is composed of a base 30 attached to a steel frame 50 and a beam main reinforcement support portion 24 provided on the base 30 and supporting a plurality of beam main reinforcements 14, and the support member 20 may be made of steel or synthetic resin. The configuration of the beam main reinforcement support portion 24 is the same as that in the first embodiment.

[0034] The base 30 is composed of a mounting portion 3002 in the form of a rectangular plate that is elongated in the beam width direction of the steel frame 50 for mounting the support member 20 to the steel frame 50, and a connecting portion 3004 in the form of a rectangular plate that is provided near the longitudinal center of the upper surface of the mounting portion 3002 and has a length in the vertical direction. Both longitudinal ends of the mounting portion 3002 are provided with female threads 30A to which bolts are fastened when the mounting portion 3002 is mounted to the steel frame 50. In this embodiment, a bolt insertion hole (not shown) is provided in the upper flange 5004 of the steel frame 50 at a position that matches the female thread 30A when the support member 20 is disposed. The beam main reinforcement support part 24 has its longitudinal center part connected to the upper part of the connection part 3004.

[0035] The support member 20 is attached to the upper surface of the upper flange 5004 by having the lower surface of the mounting portion 3002 placed on the upper surface of the upper flange 5004 of the steel frame 50, and a bolt inserted into the bolt insertion hole of the upper flange 5004 from below the upper flange 5004 is connected to the female thread 30A of the mounting portion 3002. By arranging multiple beam main reinforcements 14 at desired positions on the upper surface of the beam main reinforcement support portion 24 and fixing them to the transverse reinforcement bars 16 with tie wires, they can be accurately and easily positioned and supported above the steel frame 50. In addition, when removing the support member 20 from the steel frame 50, after fixing the multiple beam main reinforcements 14 to the transverse reinforcement bars 16 with tie wires, the bolts are removed from the upper flange 5004 and the support member 20, and the support member 20 is slid in the longitudinal direction of the steel frame 50 toward the steel beam section 10A to move it away from the reinforcement point of the concentrated reinforcement bars 16A, and it can be removed by pulling it out through the gaps in the transverse reinforcement bars 16. Therefore, the removed support member 20 can be attached to another steel frame and reused, which is advantageous in terms of reducing costs.

[0036] According to the support member 20 of the fourth embodiment, in addition to the effects of the first embodiment, the support member 20 can be easily attached to the steel frame 50 due to its simple configuration, and the support member 20 can be attached to the steel frame 50 in a stable state. In addition, since the support members 20 are connected to the steel frame 50 by bolts, after the multiple main beam reinforcements 14 are fixed to the transverse reinforcements 16 with tie wires, they can be removed before pouring concrete, and the removed support members 20 can be reused in other steel frames 50, which is advantageous in terms of reducing costs.

[0037] (Fifth embodiment) Whereas in the fourth embodiment, the mounting portion 3002 is placed on the upper flange 5004 of the steel frame 50 and attached with bolts, the fifth embodiment differs in that the upper flange 5004 of the steel frame 50 is clamped and fixed by the support member 20.

[0038] As shown in FIG. 8, the support member 20 is composed of a base 32 attached to a steel frame 50 and a beam main reinforcement support portion 24 provided at the base 32 and supporting a plurality of beam main reinforcements 14. The support member 20 may be made of steel or synthetic resin. The base 32 is composed of a mounting portion 3202, which is a bent rectangular plate for attaching the support member 20 to the steel frame 50, and a rectangular plate-shaped connecting portion 3204 having a vertical length provided at the upper part of the mounting portion 3202. The longitudinal center of the beam main reinforcement support part 24 is supported by the upper part of the connection part 3204. The mounting portion 3202 is composed of a first plate portion 3202A placed on the upper surface of the upper flange 5004 of the steel frame 50, a second plate portion 3202B bent from the end of the first plate portion 3202A and extending downward, and a third plate portion 3202C bent from the lower end of the second plate portion 3202B and facing the underside of the upper flange 5004 at a point below the underside of the upper flange 5004. The third plate portion 3202C is provided with a female thread 32A into which the bolt 34 is screwed.

[0039] In addition, in Figure 8, one mounting portion 3202 is provided on the support member 20, and one end of the upper flange 5004 of the steel frame 50 is clamped and fixed by the mounting portion 3202. However, it is also possible to provide two mounting portions 3202 on the support member 20, and clamp and fix both ends of the upper flange 5004 by the two mounting portions 3202.

[0040] The support member 20 is attached and detached as follows. When attaching the support member 20 , first, the upper flange 5004 of the steel frame 50 is inserted into the space surrounded by the first plate portion 3202 A, the second plate portion 3202 B, and the third plate portion 3202 C of the attachment portion 3202 of the support member 20 . Next, the bolt 34 is screwed into the female thread 32A of the third plate portion 3202C from below the third plate portion 3202C, and the shaft portion of the bolt 34 is caused to protrude upward from the upper surface of the third plate portion 3202C. Then, the upper flange 5004 is clamped between the tip of the shaft of the bolt 34 and the lower surface of the first plate portion 3202A, whereby the support member 20 is attached to the upper flange 5004. When removing the support member 20 , the bolts 34 are loosened and the mounting portion 3202 of the support member 20 is pulled out from the upper flange 5004 . According to the support member 20 of the fifth embodiment, the simple configuration allows it to be securely connected to the steel frame 50, and the support member 20 can be attached to the steel frame 50 in a stable state. Furthermore, the support member 20 can be removed and reused, thereby achieving the same effects as the fourth embodiment.

[0041] (Sixth embodiment) Whereas in the fourth and fifth embodiments the support member 20 is fixed to the steel frame 50 with bolts and is removable, the sixth embodiment differs in that the support member can be disassembled into multiple parts and assembled to fit the width of the flanges of the steel frame.

[0042] As shown in Figures 9 and 10, the support member 20 is composed of bases 62A, 62B arranged on either side of the upper flange 5004 of the steel frame 50, a beam main reinforcement support portion 64 provided on the upper portion of the bases 62A, 62B and supporting a plurality of beam main reinforcements 14, lower angles 66A, 66B provided on the inside of the bases 62A, 62B and placed on the upper surface of the upper flange 5004, and upper angles 68A, 68B provided on the outside of the bases 62A, 62B and on which the beam main reinforcement support portion 64 is placed, and the support member 20 may be made of steel or synthetic resin.

[0043] The bases 62A, 62B are each formed of a rectangular plate-like member, and are arranged such that the largest rectangular faces face each other when assembled. The beam main reinforcement support portion 64 is constituted by a rectangular plate-shaped member, and is provided so as to extend in the beam width direction of the steel frame 50 above the steel frame 50 during assembly. The beam main reinforcement support portion 64 has a plurality of insertion holes 6402 for fitting wedge bolts 70 at equal intervals in the beam width direction of the steel frame 50, and during assembly, the wedge bolts 70 are fitted from above into any two of the insertion holes 6402 to match the width of the upper flange 5004.

[0044] The lower angles 66A, 66B are formed by bending a rectangular plate-shaped member at a right angle, with one plate-shaped member 6602A, 6602B being provided at an opposing position on the inner surface of the base 62A, 62B, and the other plate-shaped member 6604A, 6604B being provided perpendicular to the base 62A, 62B. The upper angles 68A, 68B are formed by bending a rectangular plate-shaped member at a right angle, with one plate-shaped member 6802A, 6802B being provided on the upper part of the outer surface of the base 62A, 62B, and the other plate-shaped member 6804A, 6804B being perpendicular to the base 62A, 62B and arranged so that the upper surfaces of the plate-shaped members 6804A, 6804B are at the same height as the upper surfaces of the bases 62A, 62B. Furthermore, the plate-like members 6804A, 6804B are provided with insertion holes 6806A, 6806B for fitting the wedge bolt 70 therein, and the wedge bolt 70 is fitted from above during assembly.

[0045] When dismantling the support member 20 shown in Figure 9, by removing the wedge bolt 70, it can be disassembled into part 60A consisting of base 62A, lower angle 66A, and upper angle 68A, part 60B consisting of base 62B, lower angle 66B, and upper angle 68B, beam main reinforcement support part 64, and two wedge bolts 70, as shown in Figure 10.

[0046] Next, with reference to FIGS. 11(A), (B), and (C), a case will be described in which the parts in FIG. 10 are assembled and the support member 20 is installed on the steel frame 50. As shown in FIG. 11(A), part 60A and part 60B are placed on the upper surface of upper flange 5004 of steel frame 50 so as to face each other. That is, parts 60A and 60B are provided at positions where the lower surfaces of plate members 6604A and 6604B of lower angles 66A and 66B contact the ends of the upper surface of upper flange 5004, and the ends of upper flange 5004 abut against the inner surfaces of bases 62A and 62B. This allows the bases 62A and 62B to be installed so as to sandwich the upper flange 5004 in accordance with the length of the upper flange 5004 in the beam width direction.

[0047] Next, as shown in FIG. 11(B), the beam main bar support portion 64 is placed on the upper surfaces of the parts 60A and 60B. That is, the lower surface of the beam main reinforcement support part 64 contacts the upper surfaces of the plate-shaped members 6804A, 6804B of the upper angles 68A, 68B and the upper surfaces of the bases 62A, 62B, and is placed so that the insertion holes 6806A, 6806B of the plate-shaped members 6804A, 6804B are aligned with the insertion hole 6402 of the beam main reinforcement support part 64. At this time, it is desirable to position the center of the steel frame 50 in the beam width direction at the beam main reinforcement support portion 64 above the web 5002 for stability.

[0048] Then, as shown in FIG. 11(C), two wedge bolts 70 are inserted from above into the two insertion holes 6402 of the beam main reinforcement support part 64, and the insertion holes 6806A and 6806B of the plate members 6804A and 6804B, in that order, and fitted in place. This joins the parts 60A, 60B to the beam main reinforcement support portion 64, and attaches the support member 20 to the steel frame 50.

[0049] According to the support member 20 of the sixth embodiment, in addition to the effects of the first embodiment, the support member 20 is installed on the steel frame 50 while assembling the parts 60A, 60B to match the width of the steel frame 50, and therefore, it can be used to match the length of the upper flange 5004 of the steel frame 50 in the beam width direction. Furthermore, the support member 20, which is made up of multiple components, can be assembled and attached to the steel frame 50 by the simple task of fitting the wedge bolts 70 from above. In addition, the support members 20 are assembled and connected to the steel frame 50 by wedge bolts 70, and after multiple beam main reinforcements 14 are fixed to the transverse reinforcements 16 with tie wires, they can be dismantled by removing the wedge bolts 70 before pouring concrete, and the support members 20 can be removed as parts. In addition, the removed support members 20 can be reused for other steel frames 50 of different widths, which is advantageous in terms of reducing costs.

[0050] The upper surface of the beam main reinforcement support portion 24 of the support member 20 in the fourth and fifth embodiments is configured as a flat surface as in the first embodiment, but it is optional to provide a beam main reinforcement positioning portion consisting of a recess 2604 or a protrusion 2804 as in the second and third embodiments. Moreover, if a fitting recess with a structure in which the beam main reinforcement bars 14 fit and do not come out is provided as a positioning part instead of the recess 2604 in the second embodiment, the placed beam main reinforcement bars 14 will be integrated with the support member 20, eliminating the need for the task of fixing the multiple beam main reinforcement bars 14 to the beam main reinforcement support part 26 with tie wires. In this case, the support member 20 will not be removed, but will remain embedded in the concrete inside the beam.

[0051] In addition, in the above-described embodiment, the support member 20 is used at the end of the reinforced concrete beam section 10B of the hybrid beam 10 on the steel beam section 10A side, but it may also be provided and used at the end on the column 12 side. In addition, in the above-described embodiment, the support member 20 is used in the reinforced concrete beam portion 10B of the hybrid beam 10, but it may also be used in other structures, such as beams made of steel reinforced concrete (SRC), and may be used at both ends of the steel frame or, if the steel frame is long, in the middle of the steel frame in the longitudinal direction. [Explanation of symbols]

[0052] 10 Hybrid beams 10A Steel beam section 10B Reinforced concrete beam 14 Main beam reinforcement 16 Transverse reinforcement 16A Concentrated reinforcement 18 Concrete 20 Support member 22, 30, 32, 62A, 62B base 24, 26, 28, 64 Beam main reinforcement support section 50 Steel Frame 66A, 66B Lower angle 68A, 68B Upper angle 70 Wedge Bolt 2602, 2802 Long and thin members 2604 Recess 2804 Protrusion 3002, 3202 mounting part 3004, 3204 Connection

Claims

1. The steel beams are placed between the opposing pillars, A plurality of beam main reinforcements arranged above the steel frame and extending along the longitudinal direction of the steel frame; Concrete covering the steel frame and the plurality of beam reinforcements; A support member is provided at an upper portion of the steel frame to support the plurality of beam main reinforcements from below, The support member includes a beam reinforcement support portion that extends above the steel frame in a direction intersecting the longitudinal direction of the steel frame and supports the plurality of beam reinforcements, and a pair of parts that are arranged at both ends of the upper surface of the steel frame in the width direction and across which the beam reinforcement support portion is suspended and that are removably attached to the upper surface of the steel frame, The beam main reinforcement support portion is provided with a second insertion hole, and a positioning portion for positioning the plurality of beam main reinforcements in the beam width direction of the steel frame is provided on an upper surface of the beam main reinforcement support portion, The pair of parts each have a base portion that abuts against an end side surface in the width direction of the upper surface of the steel frame and extends upward from below the end side surface, facing each other in the width direction of the upper surface of the steel frame, a lower angle portion provided in the middle portion of the extending direction of the base portion and placed on the end portion in the width direction of the upper surface of the steel frame, and an upper angle portion that extends from the upper end of the base portion outward in the width direction of the upper surface of the steel frame, has an upper surface parallel to the upper surface of the steel frame, and is provided with a first insertion hole; The beam main reinforcement support portion is placed at both ends in the longitudinal direction on the upper surfaces of the upper angles of the pair of parts, and is attached to the upper surfaces of the pair of upper angles by wedge bolts that are detachably fitted into the first insertion holes and the second insertion holes, The second insertion holes are provided at intervals in the longitudinal direction of the beam main reinforcement support portion. A beam structure characterized by:

2. The positioning portion is composed of a plurality of recesses formed on the surface of the beam main reinforcement support portion at intervals in the width direction of the steel frame, 2. The beam structure according to claim 1.

3. The positioning portion is composed of a pair of protrusions formed on the surface of the beam main reinforcement support portion at intervals in the width direction of the steel frame, 2. The beam structure according to claim 1.

4. The beam is a hybrid beam in which the central portion of the steel frame is a steel beam portion and both ends are reinforced concrete beam portions, The support member is provided at an end of the steel beam portion side of the steel frame in the reinforced concrete beam portion, 2. The beam structure according to claim 1.

5. A support member that supports a plurality of beam main reinforcements arranged above a steel frame constituting a beam from below, The support member includes a beam reinforcement support part that is made of a plate-like member and extends above the steel frame in a direction intersecting the longitudinal direction of the steel frame to support the plurality of beam reinforcements, and a pair of parts that are arranged at both ends of the upper surface of the steel frame in the width direction and across which the beam reinforcement support part is suspended and that are removably attached to the upper surface of the steel frame, The beam main reinforcement support portion is provided with a second insertion hole, and a positioning portion for positioning the plurality of beam main reinforcements in the beam width direction of the steel frame is provided on an upper surface of the beam main reinforcement support portion, The pair of parts each have a base portion that abuts against an end side surface in the width direction of the upper surface of the steel frame and extends upward from below the end side surface, facing each other in the width direction of the upper surface of the steel frame, a lower angle portion provided in the middle portion of the extending direction of the base portion and placed on the end portion in the width direction of the upper surface of the steel frame, and an upper angle portion that extends from the upper end of the base portion outward in the width direction of the upper surface of the steel frame, has an upper surface parallel to the upper surface of the steel frame, and is provided with a first insertion hole; The beam main reinforcement support portion is placed at both ends in the longitudinal direction on the upper surfaces of the upper angles of the pair of parts, and is attached to the upper surfaces of the pair of upper angles by wedge bolts that are detachably fitted into the first insertion holes and the second insertion holes, The second insertion holes are provided at intervals in the longitudinal direction of the beam main reinforcement support portion. A support member for beam main reinforcement, characterized in that

6. The positioning portion is composed of a plurality of recesses formed on the surface of the beam main reinforcement support portion at intervals in the width direction of the steel frame, The support member for beam reinforcement according to claim 5.

7. The positioning portion is composed of a pair of protrusions formed on the surface of the beam main reinforcement support portion at intervals in the width direction of the steel frame, The support member for beam reinforcement according to claim 5.

8. The beam is a hybrid beam in which the central portion of the steel frame is a steel beam portion and both ends are reinforced concrete beam portions, The support member is provided at an end of the steel beam portion side of the steel frame in the reinforced concrete beam portion, The support member for beam reinforcement according to claim 5.

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