Fixing structure for hammer-beam and fixing method for hammer-beam

Abstract

To provide a hammer-beam fixing structure and a hammer-beam fixing method that easily secure a degree of fixation of a hammer-beam.SOLUTION: A fixing structure for a hammer-beam consists of: a precast concrete beam member (precast section 14A) that is formed integrally with a column joint and whose ends are connected to each other to form a beam 14; and a steel hammer-beam 20 that is arranged along a direction intersecting with the beam 14, and whose middle part is fixed to a connection part (cast-in-place part 14B) between the beam members, and one end of which protrudes in a direction intersecting with the beam 14, and the other end is fixed to a building frame (beam 16).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fixing structure for a spring beam and a fixing method for a spring beam. [Background technology]

[0002] The following Patent Document 1 shows a method for joining a steel beam to a PCa girder. In this method, the end of the lower flange at the end of the steel beam is removed to form a web joint with a T-shaped cross section. Then, this web joint is inserted into a slit provided in the PCa girder and supported. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-81397 Summary of the Invention [Problem to be solved by the invention]

[0004] When joining a steel beam to a precast concrete member, it is necessary to take into consideration the interference between the steel beam and reinforcing bars inside the precast concrete member, such as column main bars, hoop bars, beam main bars, stirrup bars, etc. In addition, when joining the end of a steel beam to a precast concrete member as in the above Patent Document 1, it is necessary to ensure the rigidity of the joint. In this regard, in the above Patent Document 1, the PCa main girder and the steel sub-beam are joined by grout and a support material injected into the gaps of the slits. However, with this method, when the steel beam is used as a spring beam, there is room for improvement in terms of the degree of fixation.

[0005] In consideration of the above, an object of the present invention is to provide a fixing structure and a fixing method for a spring beam that can easily ensure the fixation degree of the spring beam. [Means for solving the problem]

[0006] The fixing structure of the protruding beam of claim 1 comprises a precast concrete beam member which is formed integrally with the column joint portion and has its ends connected to form a beam, and a steel protruding beam which is arranged along the direction intersecting with the beam, has an intermediate portion fixed to the connecting portion between the beam members, has one end protruding in the direction intersecting with the beam, and has the other end fixed to the building frame.

[0007] In the fixing structure of the cantilever beam of claim 1, the cantilever beam is fixed to the connection part between the beam members made of precast concrete. Therefore, it is not necessary to manufacture the precast concrete beam with the cantilever beam embedded in it.

[0008] This makes it easy to manufacture precast concrete beam members because there is no need to consider interference between the cantilever beams and reinforcing bars. Also, compared to forming a precast concrete beam with a cantilever beam embedded in it, the precast members are easier to transport.

[0009] The end of the spring beam opposite the spring direction is fixed to the building frame. Therefore, the spring beam is supported at two points, the building frame and the beam member. This makes it easy to ensure the degree of fixation of the spring beam.

[0010] The fixing structure of the protruding beam of claim 2 is the fixing structure of the protruding beam described in claim 1, and comprises lower end reinforcements protruding from the lower portions of each of the beam members whose end faces are arranged opposite to each other and connected by joints below the protruding beam, upper end reinforcements protruding from the upper portions of each of the beam members whose end faces are arranged opposite to each other and connected by joints to both ends of rear reinforcements arranged above the protruding beam, and cast-in-place concrete covering the protruding beam, the lower end reinforcements and the upper end reinforcements.

[0011] In the fixing structure of the spring beam of claim 2, a rear bar is arranged above the spring beam. This rear bar is connected to the upper end bar of the beam member. This allows the spring beam to be dropped in from above before the rear bar is arranged. This makes it easier to install than, for example, installing it by sliding it from the side.

[0012] The method for fixing a cantilever beam of claim 3 comprises the steps of: arranging the end faces of a precast concrete beam member formed integrally with a column joint portion so as to face each other; placing the central part of a steel cantilever beam between the end faces and arranging one end of the cantilever beam so as to protrude in a direction intersecting with the beam member; placing a rear reinforcing bar above the cantilever beam and connecting the rear reinforcing bar and the upper end reinforcing bar protruding from the end face with a joint; pouring concrete to cover the cantilever beam; and fixing the other end of the cantilever beam to the building frame.

[0013] In the method for fixing the cantilever beam of claim 3, the cantilever beam is fixed to the connection between the beam members made of precast concrete. Therefore, it is not necessary to manufacture the precast concrete beam with the cantilever beam embedded in it.

[0014] This makes it easy to manufacture precast concrete beam members because there is no need to consider interference between the cantilever beams and reinforcing bars. Also, compared to forming a precast concrete beam with a cantilever beam embedded in it, the precast members are easier to transport.

[0015] The end of the spring beam opposite to the spring direction is fixed to the building frame. Therefore, the spring beam is supported at two points, the building frame and the beam member. This makes it easy to ensure the degree of fixation of the spring beam.

[0016] In addition, in this method of fixing the spring beam, a rear bar is placed above the spring beam. This rear bar is connected to the upper end bar of the beam member. This allows the spring beam to be dropped in from above before the rear bar is placed. This makes the installation easier than, for example, installing it by sliding it from the side. Effect of the Invention

[0017] According to the present invention, it is easy to ensure the degree of fixation of the spring beam. [Brief description of the drawings]

[0018] [Figure 1] 1 is a plan view partially showing a building to which a spring beam fixing structure according to an embodiment of the present invention is applied. [Diagram 2] 2 is a cross-sectional view taken along line 2-2 in FIG. 1, showing the configuration of a connection portion of a beam member in a fixing structure of a spring beam according to an embodiment of the present invention. [Diagram 3] (A) is an elevational view showing the state in which two beam members are arranged opposite each other in a method of fixing a protruding beam according to an embodiment of the present invention, (B) is an elevational view showing the state in which a protruding beam is arranged, and (C) is an elevational view showing the state in which reinforcement is placed at the connecting portion. [Figure 4] FIG. 1A is an elevation view showing a state in which two beam members are arranged opposite each other in a method for fixing a protruding beam according to a modified embodiment of the present invention, and FIG. 1B is an elevation view showing a state in which the protruding beam is arranged. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, a description will be given of a fixing structure and a fixing method of a spring beam according to an embodiment of the present invention with reference to the drawings. Components indicated by the same reference numerals in each drawing are the same components. However, unless otherwise specified in the specification, each component is not limited to one, and may be present in a plurality of components.

[0020] In addition, explanations of configurations and symbols that are duplicated in each drawing may be omitted. Note that the present disclosure is not limited to the following embodiments, and may be implemented by making appropriate modifications, such as omitting configurations, replacing them with different configurations, or combining one embodiment and various modified examples, within the scope of the purpose of the present disclosure.

[0021] <Building> 1 shows a building 10 to which a spring beam fixing structure according to an embodiment of the present invention is applied. The building 10 has a column-beam frame formed with a column 12 and beams 14 and 16.

[0022] The columns 12 are columns made of precast concrete. The beams 14 are beams made of precast concrete that are spanned across the columns 12 on at least a portion of the periphery of the building 10. "At least a portion of the periphery" refers to the portion of the periphery of the building 10 where a cantilever beam 20, which will be described later, is provided. The beams 16 are beams other than the beams 14, and are made of reinforced concrete. The beams 16 may be made of precast concrete. Furthermore, the beams 16 may be made of steel.

[0023] Cantilever beams 20 and 22 that form balconies and eaves are fixed to at least a portion of the periphery of the building 10. A "cantilever beam" refers to a cantilever beam with one end not fixed to a column or beam. A tip beam 24 is fixed to the tips (the ends facing the outdoors) of the cantilever beams 20 and 24.

[0024] <Fixing structure of the protruding beam> (Cross beam) The spring beams 20 are formed of H-shaped steel, and multiple spring beams 20 are arranged at predetermined intervals along the axial direction of the beam 14. The spring beams 20 are arranged in a direction intersecting with the beam 14, with their middle parts penetrating the beam 14, one end protruding in the direction intersecting with the beam 14, and the other end fixed to the beam 16 which is the framework of the building.

[0025] The spring beams 22 are formed of H-shaped steel, and a plurality of them are arranged at predetermined intervals along the axial direction of the beam 14. The spring beams 22 are arranged alternately with the spring beams 20. The spring beams 22 are arranged in a direction intersecting with the beam 14, with one end protruding in the direction intersecting with the beam 14 and the other end fixed to the column 12 which is the framework of the building.

[0026] The cantilever beam 22 has a smaller cross section than the cantilever beam 20, and the proportion of the load acting from the balcony, eaves, etc. is smaller than that of the cantilever beam 20. Therefore, the cantilever beam 22 may have a smaller degree of fixation at the end compared to the cantilever beam 20.

[0027] In this regard, the spring beam 22 is fixed to the column 12 via a base plate 22A and an anchor bolt 22B. The anchor bolts 22B are arranged in the column 12 with a number and cross-sectional dimensions that do not interfere with the arrangement of the column main reinforcement bars and hoop reinforcement bars (not shown) inside the column 12. Therefore, the spring beam 22 is unlikely to be an obstacle when manufacturing the column 12.

[0028] (Fixing structure of the spring beam) The beam 14 through which the spring beam 20 penetrates includes a precast portion 14A and a cast-in-place portion 14B. The precast portion 14A is a beam member formed integrally with the column 12. The cast-in-place portion 14B is a connecting portion that connects the precast portions 14A to each other.

[0029] In the following description, the portion formed by the precast section 14A, which is a beam member, and the column 12 may be referred to as the unit 10A. The unit 10A is formed with one column 12 and two precast sections 14A protruding from two opposing side surfaces of the column 12, and is manufactured, for example, in a factory. The unit 10A is disposed on the outer periphery of the building 10 in a portion where the protruding beam 20 is provided.

[0030] The column 12 may be formed by separately forming the column body and the joint. In this case, the precast portion 14A is formed integrally with the joint of the column 12.

[0031] The beam 14 is formed by connecting the precast sections 14A of the adjacent units 10A by cast-in-place sections 14B. The spring beam 20 passes through the cast-in-place sections 14B and is fixed to the cast-in-place sections 14B.

[0032] (Configuration of the connecting part) In Fig. 2, the boundary between the precast section 14A and the cast-in-place section 14B as a connecting section is shown by a dashed line. In this figure, for the convenience of explaining the configuration, the internal structure of the precast section 14A and the cast-in-place section 14B is shown by a solid line.

[0033] The precast portion 14A is provided with beam reinforcement bars 30A and stirrup reinforcement bars 30B. The beam reinforcement bars 30A protrude from the precast portion 14A.

[0034] Of the beam main reinforcements 30A protruding from the adjacent precast sections 14A, the lower end reinforcements are joined at the cast-in-place section 14B by mechanical joints 40. As a result, the lower end reinforcements of the adjacent precast sections 14A are joined at the cast-in-place section 14B.

[0035] Of the main beam reinforcements 30A protruding from adjacent precast sections 14A, the upper end reinforcements are joined by mechanical joints 40 and rear reinforcements 32A in the cast-in-place section 14B.

[0036] Specifically, rear-insertion bars 32A are arranged above the spring beam 20, and both ends of the rear-insertion bars 32A are inserted into the mechanical joints 40. The upper end bars of the adjacent precast sections 14A are inserted into these two mechanical joints 40, respectively. As a result, the upper end bars of the adjacent precast sections 14A are joined to each other at the cast-in-place sections 14B.

[0037] In addition, stirrups 32B are arranged in the cast-in-place section 14B. The stirrups 32B are arranged to avoid the spring beams 20.

[0038] <How to fix the protruding beam> In a method of fixing the spring beam 20, first, the end faces of the precast portion 14A formed integrally with the column 12 (see FIG. 1) are arranged to face each other as shown in FIG. 3(A).

[0039] Then, as shown in Figure 1, the central portion of the protruding beam 20 is placed in the area sandwiched between the end faces of the precast portion 14A, and the end portion of the protruding beam 20 is positioned so that it protrudes in a direction intersecting with the precast portion 14A (a direction perpendicular to the axial direction of the precast portion 14A).

[0040] At this time, as shown in FIG. 3(A), the spring beam 20 is placed by dropping it from above the precast portion 14A into between the precast portions 14A.

[0041] 3(B), the rear bars 32A are placed above the cantilever beam 20, and the rear bars 32A and the upper end bars of the beam main bars 30A protruding from the end face of the precast section 14A are connected with mechanical joints 40. The lower end bars of the beam main bars 30A protruding from the end face of the precast section 14A are also connected with mechanical joints 40.

[0042] In addition, the lower end bars of the beam main bars 30A may be connected to each other with a mechanical joint 40 before the projection beam 20 is arranged.

[0043] Next, as shown in Fig. 3(C), stirrups 32B are arranged between the precast sections 14A. After that, the formwork is assembled and concrete is poured between the precast sections 14A to form the cast-in-place sections 14B shown in Fig. 2. As a result, the center of the cantilever beam 20 is fixed to the beam 14 as shown in Fig. 1.

[0044] The end of the protruding beam 20 (the end on the side that does not protrude) is fixed to the beam 16. This fixing method is arbitrary, but for example, a fixing bracket may be joined to the beam 16, and the protruding beam 20 may be fixed to this bracket.

[0045] <Action and Effects> In the fixing structure and fixing method of the spring beam according to the embodiment of the present invention, the spring beam 20 is fixed to the cast-in-place part 14B which is the connecting part between the precast parts 14A, as shown in Fig. 1. Therefore, it is not necessary to manufacture the precast concrete beam 14 with the spring beam 20 embedded in it.

[0046] This makes it easy to manufacture the precast section 14A, since there is no need to consider interference between the reinforcing bars and the cantilever beam 20. Also, compared to the case of forming a precast concrete beam with the cantilever beam 20 embedded in it, the precast member is easier to transport.

[0047] The end of the retractable beam 20 opposite to the retracting direction is fixed to the building frame, i.e., the beam 16. Therefore, the retractable beam 20 is supported at two points, the beam 14 and the beam 16. This makes it easy to ensure the degree of fixation of the retractable beam 20.

[0048] In addition, in the fixing structure of the spring beam according to the embodiment of the present invention, as shown in Fig. 2, a rear bar 32A is arranged above the spring beam 20. This rear bar 32A is connected to the upper end bar of the beam main bar 30A of the precast portion 14A.

[0049] 3A, the spring beam 20 can be dropped in from above before the rear reinforcement bars 32A are placed. This makes the installation easier than, for example, installing the spring beam by sliding it from the side.

[0050] In the present invention, it is not necessarily required to install the spring beam 20 by dropping it from above. The spring beam 20 may be installed by sliding it from the side.

[0051] In this case, for example, as shown in Figures 4(A) and (B), the precast sections 14A can be manufactured so that through holes are formed for passing the spring beams 20 through when they are arranged opposite each other. To connect these precast sections 14A, a mechanical joint 40 is placed on one end face of the precast sections 14A, and the beam main reinforcement 30A protruding from the other end face is inserted into this mechanical joint 40.

[0052] According to this embodiment, it is only necessary to fill the area around the through hole and the protruding beam 20 with concrete, thereby reducing the labor required for pouring in-situ concrete.

[0053] In the above embodiment, the spring beam 22 is provided in addition to the spring beam 20, but the embodiment of the present invention is not limited to this. For example, the spring beam 22 may be omitted. In this way, the present invention can be embodied in various forms. [Explanation of symbols]

[0054] 10. Building 12 Pillars 14 Beam 16 Beam (frame) 14A Precast section (beam member) 14B Cast-in-place section (connection section) 20 Cantilever beam 30A Beam main reinforcement (upper end reinforcement, lower end reinforcement) 32A Back muscle 40 Mechanical joints (joints)

Claims

1. A precast concrete beam member that is integrally formed with the column joint and has its ends connected to each other to form a beam; A steel-framed protruding beam is arranged along a direction intersecting with the beam, has an intermediate portion fixed to a connecting portion between the beam members, has one end protruding in a direction intersecting with the beam, and has the other end fixed to a building frame; A fixing structure for a spring beam.

2. A lower end bar protruding from a lower portion of each of the beam members whose end faces are arranged opposite to each other and connected by a joint below the protruding beam; An upper end bar protruding from the upper portion of each of the beam members whose end faces are arranged opposite to each other and connected to both ends of the rear bar arranged above the protruding beam by a joint; Cast-in-place concrete covering the spring beam, the lower end bar and the upper end bar; The fixing structure of claim 1 .

3. a step of arranging end faces of precast concrete beam members formed integrally with the column joint portions so as to face each other; A step of arranging a central portion of a steel-framed protruding beam in a portion sandwiched between the end faces, and arranging one end of the protruding beam so as to protrude in a direction intersecting with the beam member; A process of arranging a rear bar above the protruding beam and connecting the rear bar and the upper end bar protruding from the end surface with a joint, pouring concrete to cover the spring beam; Fixing the other end of the spring beam to a building frame; A method for fixing a spring beam comprising:

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