Column joint structure and column construction method

Abstract

To provide the jointing structure of a column allowing short time construction, and sure transmission of a force due to load between the column main reinforcement of a reinforced concrete column member and a steel frame column member, and a construction method.SOLUTION: The jointing structure 10 of a column is formed by jointing a steel frame column member 11 to an RC column member 16 arranged thereon. The RC column member 16 is precast concrete, and mechanical joints 17 fixing column main reinforcements 15 are buried in the RC column member 16. Lower parts of the column main reinforcements 15 are fixed to mechanical joints 12 welded to the steel frame column member 11, and the column main reinforcements 15 are fixed to the mechanical joints 17 of the RC column member 16.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a column joint structure formed by connecting a steel frame column member and a reinforced concrete column member, and a column construction method. [Background technology]

[0002] Conventionally, a column joint structure in which a reinforced concrete column member is connected to a steel column member is known. In this joint structure, a transition part made of steel reinforced concrete is provided around the steel column member by placing the column main bars of the reinforced concrete column member and then pouring concrete. This transition part requires pouring concrete on-site, which takes time.

[0003] Also, a column structure has been studied in which a reinforced concrete column member and a steel column member are connected without providing a switching portion made of steel reinforced concrete (for example, see Patent Document 1). The joint structure of the technology described in this document includes a first member and a second member. The first member includes a hollow tubular portion and a first concrete filled inside the hollow tubular portion. The second member includes a main reinforcement, one end of which is arranged inside the hollow tubular portion through the open end, a tie bar arranged to surround the periphery of the main reinforcement, and a second concrete poured to cover the portion of the main reinforcement and the tie bar that is not located inside the hollow tubular portion. Then, a slip-out prevention bar is provided, which is arranged from the outer periphery of the hollow tubular portion to the inside of the hollow tubular portion, to prevent the second member from slipping out of the first member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-132948 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, at the switching portion of the structure shown in Patent Document 1, it was necessary to provide a member to prevent the reinforcing bar from coming loose. For this reason, it took time to install the member to prevent the reinforcing bar from coming loose. [Means for solving the problem]

[0006] The column joint structure that solves the above-mentioned problems is a column joint structure formed by connecting a steel column member and a reinforced concrete column member, and includes an attachment member fixed by welding to a steel plate that constitutes the steel column member, and a mechanical joint arranged in the axial direction of the column main reinforcement of the reinforced concrete column member and welded to the attachment member, and the reinforced concrete column member is connected to the steel column member via the column main reinforcement fixed to the mechanical joint.

[0007] The method for constructing a column that solves the above problem is a method for constructing a column that is constructed by connecting a steel column member and a reinforced concrete column member. hand, The steel column member includes a mounting member fixed to a steel plate constituting the steel column member by welding, and a mechanical joint arranged in the axial direction of the column main reinforcement of the reinforced concrete column member and welded to the mounting member, The reinforced concrete column member has a central axis at a position shifted from the central axis of the steel column member, and the mounting member is disposed on the steel column member so as to be in a position where the column main reinforcement is fixed to the mechanical joint, The mechanical joint of the steel column member The above Column main reinforcement Fix Determine. Effect of the Invention

[0008] According to the present invention, construction can be performed in a short time, and forces such as normal forces due to loads can be reliably transmitted between the column main reinforcement of a reinforced concrete column member and a steel column member. [Brief description of the drawings]

[0009] [Figure 1] 1A and 1B are explanatory diagrams illustrating a column joint structure in the first embodiment, where (a) is a front view and (b) is a cross-sectional view taken along line 1b-1b in (a). [Diagram 2]FIG. 2 is an explanatory diagram for explaining a column connection method in the first embodiment, in which (a) shows a state in which a steel column member is placed, and (b) shows a state in which a column main bar is fixed to the steel column member. [Diagram 3] 3A and 3B are explanatory diagrams illustrating a column joint structure in a second embodiment, where (a) is a front view and (b) is a cross-sectional view taken along line 3b-3b in (a). [Figure 4] 11A and 11B are explanatory diagrams illustrating a method of constructing columns in a modified example, in which (a) shows a reinforced concrete column member in which the main column bars are directly embedded, and (b) shows a steel column member in which the main column bars are directly welded. [Diagram 5] 11A to 11D are explanatory diagrams illustrating the column joint structure in a modified example, where (a) is a front view, (b) is a cross-sectional view along line 5b-5b, (c) is a cross-sectional view along line 5c-5c, and (d) is a front view of the mounting member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (First embodiment) Hereinafter, a first embodiment embodying a column joint structure and a column construction method will be described with reference to Figs. 1 and 2.

[0011] As shown in Fig. 1(a), a column joint structure 10 of this embodiment is composed of a steel column member 11 and a reinforced concrete column member (RC column member) 16 placed on top of the steel column member 11. In this embodiment, the central axis of the steel column member 11 and the central axis of the RC column member 16 are configured to coincide with each other. In addition, a steel beam 19 is provided at the upper end of the steel column member 11.

[0012] As shown in FIG. 1( b ), the horizontal cross sections of the steel column member 11 and the RC column member 16 are substantially square, and the horizontal cross section of the steel column member 11 is smaller than the horizontal cross section of the RC column member 16 . The steel column member 11 is a column member formed by combining four plate-like steel plates 11a into a square cylindrical shape.

[0013] As shown in Fig. 1(a), a plurality of mechanical joints 12 are welded to each steel plate 11a at a position that will be the upper part of the outer circumferential surface of the steel column member 11. For example, a screw-type mechanical joint is used as the mechanical joint 12. The mechanical joints 12 are provided at positions corresponding to the column main reinforcement bars 15 of the RC column member 16. The mechanical joints 12 are welded to the steel plate 11a in advance at a factory or the like.

[0014] The column main reinforcement 15 is threaded so as to be fixed to the mechanical joint 12. The RC column member 16 is a column member made of concrete with multiple column reinforcements built in, and is precast concrete prepared in advance in a factory or the like. A mechanical joint 17 is embedded in the end of the RC column member 16 on the side of the steel column member 11. A mortar-filled mechanical joint can be used as this mechanical joint 17. A main bar 18 of the column reinforcement built into the RC column member 16 is fixed to the upper part of this mechanical joint 17.

[0015] Next, a method for constructing the above-mentioned column joint structure 10 will be described with reference to Figs. First, as shown in Fig. 2(a), a steel column member 11 is erected. In this case, four steel plates 11a with mechanical joints 12 fixed to the upper part are assembled in advance at a factory or the like so that the mechanical joints 12 are arranged on the outside, and the steel column member 11 is constructed by welding the connection parts between the steel plates 11a.

[0016] 2(b), column main reinforcements 15 (connecting reinforcements) are inserted into the mechanical joint 12. In this case, the column main reinforcements 15 are fixed to the steel column member 11 by screwing the lower part of the column main reinforcements 15 into the mechanical joint 12.

[0017] Then, the RC column member 16 is placed so that the column main reinforcements 15 are inserted into the mechanical joints 17 of the RC column member 16. Then, mortar is injected into the mechanical joints 17 into which the column main reinforcements 15 have been inserted, thereby fixing the column main reinforcements 15 to the RC column member 16. In this way, the RC column member 16 is joined to the steel column member 11 and the RC column member 16 via the column main reinforcements 15.

[0018] According to this embodiment, the following effects can be obtained. (1-1) In this embodiment, the column main reinforcement 15 of the RC column member 16 is fixed to the mechanical joint 12 welded to the steel column member 11. As a result, the column main reinforcement 15 of the RC column member 16 and the steel column member 11 are connected via the mechanical joint 12, so that forces such as a vertical force due to a load applied to the column main reinforcement 15 can be reliably transmitted to the steel column member 11.

[0019] Normally, a steel column is finished with a fireproof coating, so the finished surface is larger than the outer periphery of the steel column. By making the cross-sectional area of ​​the steel column member 11 smaller than the cross-sectional area of ​​the RC column member 16, the finished surface of the steel column member 11 can be made flush with the finished surface of the RC column member 16 or located inside the finished surface of the RC column member 16, expanding the range of designs. For example, a large space floor can be formed using the steel column members 11, and a residential floor consisting of small rooms can be formed using the RC column members 16.

[0020] (1-2) In this embodiment, the RC column member 16 is formed of precast concrete. This eliminates the need to pour concrete on-site, making it possible to construct the column joint structure 10 in a short period of time.

[0021] (1-3) In this embodiment, the steel column member 11 is constructed using a steel plate 11a to which a mechanical joint 12 is welded in advance. This eliminates the need for on-site welding work, and allows the column joint structure 10 to be constructed in a short time.

[0022] Second embodiment Next, a second embodiment that embodies a column joint structure and a column construction method will be described with reference to Fig. 3. Since this embodiment is configured by only changing the steel column member 11 of the first embodiment, the same parts are given the same reference numerals and detailed descriptions thereof will be omitted.

[0023] As shown in FIG. 3(a), in a joint structure 20 of this embodiment, an RC column member 16 is connected onto a steel column member 21. As in the above embodiment, the central axis of the steel column member 21 is the same as the central axis of the RC column member 16, and the cross section of the steel column member 21 is smaller than the cross section of the RC column member 16. In addition, a steel beam 29 is provided at the upper end of the steel column member 21.

[0024] As shown in Figure 3(b), a mechanical joint 22 is welded to the steel plate 21a that constitutes the steel column member 21 at a position corresponding to the column main reinforcement 15 of the RC column member 16, at a position that forms the upper part of the inner surface of the steel column member 11. In this embodiment, the column joint structure 20 is constructed in the same manner as in the first embodiment.

[0025] According to this embodiment, in addition to the effects similar to those described in (1-1) to (1-3) above, the following effects can be obtained. (2-1) In this embodiment, the mechanical joint 22 is provided on the inside of the steel plate 21a. This makes it possible to make the outer surface of the steel column member 21 smooth, facilitating finishing processing.

[0026] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. In the first embodiment, the mechanical joint 12 is welded to the outside of the steel column member 11, and in the second embodiment, the mechanical joint 22 is welded to the inside of the steel column member 21. The position where the mechanical joint 12 is provided is not limited to the inside or outside. For example, depending on the position of the column main reinforcement 15 embedded in the reinforced concrete column member and the shape of the steel column member, some of the mechanical joints may be welded to the inside of the steel column member 11 and the remaining mechanical joints may be welded to the outside of the steel column member 11.

[0027] In each of the above embodiments, the RC column member 16 is made of precast concrete in which the mechanical joint 12 for fixing the column main reinforcement 15 is embedded. Instead of the mechanical joint 12, the RC column member 16 may be made of precast concrete in which the column main reinforcement 15 is directly embedded. Specifically, as shown in FIG. 4(a), the reinforced concrete column member (RC column member) 26 may be made of precast concrete in which the column main reinforcement 26a protrudes downward. In this case, since the multiple column main reinforcement 26a of the RC column member 26 cannot be rotated individually, a mortar-filled mechanical joint is used as the mechanical joint 32 welded to the steel column member 11.

[0028] In the above embodiment, the column main reinforcement 15 is fixed to the steel column members 11, 21 via the mechanical joints 12, 22. The method of fixing the column main reinforcement to the steel column members is not limited to the method of fixing the column main reinforcement to the steel column members via the mechanical joints, and the mechanical joints may be omitted. Specifically, as shown in FIG. 4(b), the column main reinforcement 25 is welded to the steel column member 31. Then, the column main reinforcement 25 is inserted into the mechanical joint 17 embedded in the RC column member 16.

[0029] In the above embodiment, a screw-type mechanical joint or a mortar-filled mechanical joint is used as the mechanical joints 12, 22, 32 provided in the steel column members 11, 21. Also, a mortar-filled mechanical joint is used as the mechanical joint 17 embedded in the RC column member 16. As long as the steel column members 11, 21 and the column main reinforcement of the RC column member 16 can be fixed, the type of mechanical joint is not limited.

[0030] In the joint structures 10 and 20 of the above embodiments, the central axis of the steel column member 11 and the central axis of the RC column member 16 are aligned. The arrangement of the steel column member 11 and the RC column member 16 is not limited to this. For example, the joint structure may be one in which the central axis of the steel column member and the central axis of the reinforced concrete column member are offset from each other.

[0031] For example, a joint structure 40 shown in Fig. 5(a) is composed of a steel column member 41 and a reinforced concrete column member (RC column member) 46 provided on the steel column member 41. The steel column member 41 is arranged so that the cross section becomes larger at the joint where a steel beam 49 is connected according to the position of the RC column member 46. Fig. 5(b) is a cross-sectional view taken along line 5b-5b, and Fig. 5(c) is a cross-sectional view taken along line 5c-5c.

[0032] The steel column member 41 includes a steel plate 41a, a mounting member 41b, a reinforcing member 41c, and a diaphragm 43. The steel plate 41a is a plate-like member that forms the outer periphery of the steel column member 41. The mounting member 41b and the reinforcing member 41c are plate-like members that are disposed directly below the RC column member 46, and support the weight of the RC column member 46. Furthermore, both ends of the mounting member 41b and the reinforcing member 41c are welded to the steel plate 41a, and transmit the weight of the RC column member 46 to the steel plate 41a.

[0033] 5(d), the upper end of the mounting member 41b is provided with a notch S1 corresponding to the position of the mechanical joint 42. This notch S1 ensures a space for the mechanical joint 42 when welding the mechanical joint 42. Similarly to the mounting member 41b, the upper end of the reinforcing member 41c is provided with a notch corresponding to the position of the mechanical joint 42.

[0034] As shown in Fig. 5(b), a mechanical joint 42 is welded to the steel plate 41a and mounting member 41b protruding from the right side of the steel column member 41 at the connection portion. The column main reinforcement 46a of the RC column member 46 is fixed to these mechanical joints 42. This ensures that forces such as the vertical force caused by the load of the column main reinforcement 46a of the RC column member 46 can be transmitted to the steel column member 41 without aligning the central axis C2 of the RC column member 46 with the central axis C1 of the steel column member 41. This allows the arrangement of the steel column member 41 and the RC column member 46 to be changed, increasing the freedom of design of the interior space. Furthermore, a mechanical joint may be embedded in the RC column member 46 instead of the column main reinforcement 46a, and the column main reinforcement fixed to the mechanical joint may be directly welded to the steel plate 41a or the mounting member 41b of the steel column member 41.

[0035] In each of the above embodiments, the steel column members 11, 21 are constructed by assembling four steel plates 11a, 21a. The construction of the steel column members 11, 21 is not limited to assembling steel plates, and may be constructed, for example, by steel pipes. Furthermore, instead of the steel column members 11, 21, a concrete filled steel tube structure (CFT) in which concrete is poured may be used to construct a column joint structure.

[0036] In the above embodiments, the horizontal cross sections of the steel column members 11, 21 and the RC column member 16 are substantially square. The cross-sectional shapes of these columns are not limited to this, and may be circular or elliptical. Furthermore, the steel column members 11, 21 and the RC column member 16 may be formed with different cross-sectional shapes.

[0037] In the above embodiment, the RC column member 16 is connected on top of the steel column members 11, 21. However, this is not limited to the above, and a column joint structure in which a steel column member is connected on top of a reinforced concrete column member may be used. In this case, precast concrete with embedded column main bars protruding upward may be used as the reinforced concrete column member.

[0038] In each of the above embodiments, the column main reinforcement 15 of the RC column member 16 is fixed to the mechanical joints 12, 22 provided in the steel column members 11, 21 by welding. The method of fixing the column main reinforcement of the RC column member to the mechanical joints provided in the steel column member or directly to the steel column member is not limited to welding.

[0039] Next, the technical ideas that can be understood from the above embodiment and other examples will be described below. (a) the reinforced concrete column member is made of precast concrete; The column joint structure according to claim 1, characterized in that the column main reinforcement embedded in the precast concrete or the main reinforcement fixed to a mechanical joint embedded in the precast concrete is connected to the steel column member. (b) A column joint structure as described in (a) or (b), characterized in that the reinforced concrete column member is placed on the steel column member. (c) the steel column member includes a mounting member welded and fixed to a steel plate constituting the steel column member; 2. A column joint structure according to claim 1, (a) or (b), characterized in that the mechanical joint or the column main reinforcement is welded to the mounting member. (d) A steel column member constituting a column, A steel column member characterized by being provided with mechanical joints fixed by welding in correspondence with the arrangement of main column reinforcements embedded in a reinforced concrete column member. [Explanation of symbols]

[0040] C1, C2...central axis, S1...notch, 10, 20, 40...joint structure, 11, 21, 31, 41...steel column member, 11a, 21a, 41a...steel plate, 12, 17, 22, 32, 42...mechanical joint, 15, 25, 26a, 46a...column main reinforcement, 16, 26, 46...reinforced concrete column member (RC column member), 18...main reinforcement, 19, 29, 49...steel beam, 41b...mounting member, 41c...reinforcing member, 43...diaphragm.

Claims

1. A column joint structure formed by connecting a steel column member and a reinforced concrete column member, A mounting member fixed by welding to a steel plate constituting the steel column member; a mechanical joint arranged in the axial direction of the column main reinforcement of the reinforced concrete column member and welded to the mounting member; The reinforced concrete column member has a central axis at a position shifted from the central axis of the steel column member, The mounting member is disposed on the steel column member so as to be at a position where the column main reinforcement is fixed to the mechanical joint, A column joint structure, characterized in that the reinforced concrete column member is connected to the steel frame column member via a column main bar fixed to the mechanical joint.

2. A method for constructing a column by connecting a steel column member and a reinforced concrete column member, comprising the steps of: The steel column member is A mounting member fixed by welding to a steel plate constituting the steel column member; a mechanical joint arranged in the axial direction of the column main reinforcement of the reinforced concrete column member and welded to the mounting member; The reinforced concrete column member has a central axis at a position shifted from the central axis of the steel column member, The mounting member is disposed on the steel column member so as to be at a position where the column main reinforcement is fixed to the mechanical joint, A column construction method comprising fixing the column main reinforcement to the mechanical joint of the steel column member.

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