Connection structure, connection method

Abstract

To provide a connection structure and connection method that facilitates the connection of structural parts made of different materials. [Solution] A connection structure 60 between a reinforced concrete column 20 and a steel column 40, comprising a protruding portion 21a from which the threaded reinforcing bars, which are the main reinforcement bars 21 of the reinforced concrete column 20, protrude from the upper end of the reinforced concrete column 20, and a plate 42 located at the upper end of the reinforced concrete column 20 to which the steel column 40 is fixed, wherein the protruding portion 21a and the plate 42 are fastened together.

Description

Technical Field

[0001] The present disclosure relates to a connection structure and a connection method.

Background Art

[0002] Conventionally, in a building structure, it is sometimes necessary to join structural parts made of different materials. For example, Patent Document 1 discloses a column base structure in which the lower end of a threaded deformed bar is fixed to a fixing plate embedded in the foundation concrete, while the upper end of the threaded deformed bar is exposed upward from the foundation concrete, and a steel plate is fixed to the exposed part of the threaded deformed bar with a plate nut.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Incidentally, it is sometimes necessary to use different materials for columns between upper and lower floors or for beams within the same floor. In this case, since reinforcing bars are already embedded in the structural parts made of reinforced concrete, there is little space for installing anchor bolts for connecting structural parts made of steel.

Means for Solving the Problems

[0005] A connection structure according to one aspect of the present disclosure is a connection structure between a first structural part made of reinforced concrete and a second structural part made of steel, having a protruding part where a threaded deformed bar, which is a main reinforcing bar of the first structural part, protrudes from an end of the first structural part, and a plate located at the end of the first structural part to which the second structural part is fixed, and the protruding part and the plate are fastened.

Effects of the Invention

[0006] According to this disclosure, it is easy to connect structural parts made of different materials. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic diagram showing a part of a building. [Figure 2] Figure 2 shows the connection structure between reinforced concrete columns and steel columns as viewed from above. [Figure 3] Figure 3 shows the connection structure assuming that the line is cut along the 3-3 indicator shown in Figure 2. [Figure 4] Figure 4 shows the method of connecting reinforced concrete columns and steel columns. [Figure 5] Figure 5 shows the connection structure between a reinforced concrete beam and a steel beam. [Figure 6] Figure 6 shows the connection structure assuming that the line is cut along the 6-6 indicator shown in Figure 5. [Figure 7] Figure 7 shows the connection structure between a reinforced concrete beam and a steel beam as viewed from the side. [Figure 8] Figure 8 shows a method for connecting a reinforced concrete beam to a steel beam. [Figure 9] Figure 9 shows the connection structure between the reinforced concrete beam and the steel beam in the modified example. [Figure 10] Figure 10 is a schematic diagram showing a part of the building in the example of the modification. [Modes for carrying out the invention]

[0008] The following describes a connection structure and connection method relating to one aspect of this disclosure. [First Embodiment] <Overview of the building> As shown in Figure 1, the building 10 has a first floor section 11 containing one or more floors, and a second floor section 12 that is continuous with the upper part of the first floor section 11 and also contains one or more floors. Hereinafter, the vertical direction will be referred to as the Z direction, and the two directions perpendicular to the horizontal plane perpendicular to the Z direction will be referred to as the X direction and the Y direction, respectively. In each direction, one direction will be indicated with a + sign, and the opposite direction will be indicated with a - sign. The +Z direction is the upward direction, and the -Z direction is the downward direction. Also, reinforced concrete will be referred to as RC (Reinforced Concrete), and steel will be referred to as S (Steel).

[0009] As an example, the first floor 11 is made of reinforced concrete (RC). The columns of the first floor 11 are RC columns 20. The RC columns 20 are not limited to being square columns, but may also be cylindrical. The beams of the first floor 11 are RC beams 30. Some of the multiple beams in the first floor 11 may be steel beams 50. As an example, the second floor 12 is made of steel (S). The columns of the second floor 12 are steel columns 40. The steel columns 40 are not limited to being square columns, but may also be cylindrical. The beams of the second floor 12 are steel beams 50. The steel columns 40 may be square steel pipes, round steel pipes, or H-shaped steel. The steel beams 50 may be simply supported beams or cantilevered beams, and may be structural steel beams, plate beams, truss beams, or other types of beams. The structures of each floor 11, 12 may include walls, floors, etc.

[0010] <Connection Structure> A connecting structure 60 that connects the upper end of the RC column 20 and the lower end of the S column 40 will be described. The RC column 20 constitutes the structure of the first floor section 11, and the S column 40 constitutes the structure of the second floor section 12. The RC column 20 is an example of the first structural section, and the S column 40 is an example of the second structural section.

[0011] As shown in FIGS. 2 and 3, the RC column 20 is formed by embedding a plurality of column main reinforcements 21 and a plurality of hoop reinforcements 22 in the concrete Cn. Each column main reinforcement 21 is a threaded deformed bar extending along the Z direction inside the RC column 20. Each column main reinforcement 21 of the RC column 20 penetrates the joint 61 along the Z direction and protrudes in the +Z direction from the upper end face 61a of the joint 61. The upper end face 61a of the joint 61 is the upper end portion of the RC column 20. Among each column main reinforcement 21, the portion protruding from the upper end face 61a of the joint 61 is the protruding portion 21a.

[0012] The RC beam 30 is formed by embedding a plurality of beam main reinforcements 31 and a plurality of stirrups 32 in the concrete Cn. Each beam main reinforcement 31 is a threaded deformed bar extending along the X direction or the Y direction, which is the direction in which the RC beam 30 extends, inside the RC beam 30. When the RC beam 30 is provided on both sides of the joint 61 in the Y direction, each beam main reinforcement 31 may penetrate the joint 61 from the RC beam 30 on the -Y direction side and continue to the RC beam 30 on the +Y direction side.

[0013] Also, when the RC beam 30 is provided on one side (for example, the -X direction) of the joint 61 in the X direction, it is preferable to embed each base end portion of the plurality of beam main reinforcements 31 in the joint 61. Each beam main reinforcement 31 is a threaded deformed bar extending along the X direction inside the RC beam 3;0. In this case, it is preferable to attach a nut 33 to the base end portion of each beam main reinforcement 31. <000;086> When viewed from the Z direction, at the joint 61, a plurality of beam main reinforcements 31 extending along the X direction and a plurality of beam main reinforcements 31 extending along the Y direction intersect. Also, when viewed from the X direction or the Y direction, a plurality of beam main reinforcements 31 and a plurality of column main reinforcements 21 intersect. Note that the RC beam 30 may be provided on one side of the joint 61 in the Y direction. The RC beam 30 may be provided on both sides of the joint 61 in the X direction.

[0015] A plate 42 is fixed to the lower end of the S column 40. The plate 42 is positioned on the upper end surface 61a of the joint 61. When viewed from the Z direction, the plate 42 has a size and shape that cover all the positions where the plurality of column main reinforcements 21 are arranged. When viewed from the Z direction, the shape and size of the plate 42 may be the same as, or smaller than, the shape and size of the RC column 20 when assumed to be cut in the XY plane. A plurality of insertion holes 43 penetrating along the Z direction are formed in the plate 42. The protruding portions 21a of the column main reinforcements 21 are respectively inserted into the insertion holes 43. Plate nuts 44 are respectively screwed onto the protruding portions 21a. That is, the protruding portions 21a and the plate 42 are fastened. Non-shrinking mortar 45 is filled between the upper end surface 61a of the joint 61 and the plate 42.

[0016] <Connection method> As shown in FIG. 4, in step S100, each reinforcing bar is arranged and a formwork is formed. In step S100, each column main reinforcement 21 is arranged such that the end portion on the +Z direction side thereof protrudes from the upper end surface 61a of the joint 61. In step S110, the concrete Cn is placed into the formwork. Thereby, the RC column 20 is formed and the protruding portions 31a are formed. Note that the upper end surface 61a of the joint 61 may be leveled using mortar.

[0017] In step S120, the S column 40 is installed. Assume that a plate 42 is fixed to the lower end of the S column 40. The plate 42 is placed on the upper end surface 61a of the joint 61. While inserting the protruding portions 21a protruding from the upper end surface 61a of the joint 61 into the respective insertion holes 43 formed in the plate 42, the S column 40 is erected. Plate nuts 44 are respectively screwed onto the protruding portions 21a to temporarily fix the S column 40.

[0018] In step S130, non-shrinking mortar 45 is filled into the gap between the joint � and the plate 42. Further, non-shrinking mortar 45 is filled into each gap between the protruding portion 21a and the insertion hole 43, and each gap between the plate 42 and the plate nut 44.

[0019] In step S140, the plate nut 44 is tightened to fill the gap between the joint 61 and the plate 42, the gap between the protrusion 21a and the insertion hole 43, and the gap between the plate 42 and the plate nut 44 with non-shrink mortar 45. If necessary, the plate nut 44 is further tightened to fix the plate 42 to the joint 61, i.e., the upper end of the RC column 20.

[0020] <Mechanism of Action and Effects> The operation and effects of this embodiment will now be described. (1-1) At the upper end (joint 61) of the RC column 20, in addition to multiple column main reinforcement bars 21, multiple beam main reinforcement bars 31 are also arranged, resulting in limited space for installing anchor bolts. It is conceivable to create a flange of concrete Cn surrounding the column main reinforcement bars 21 and install anchor bolts there, but this would lead to an increase in the size and weight of the joint 61. Furthermore, from the standpoint of ensuring connection strength, it is necessary to ensure a sufficient number of anchor bolts. In contrast, with the connection structure 60, the column main reinforcement bars 21 can also serve as anchor bolts, eliminating the need to create additional space for anchor bolts. Therefore, the upper end of the RC column 20 and the lower end of the S column 40 can be easily connected.

[0021] (1-2) All of the main reinforcement bars 21 of the RC column 20 to be connected are used as anchor bolts for connection to the S column 40. Therefore, the strength of the connection structure 60 can be increased. [Second Embodiment] The connection structure 60 of this embodiment is configured to connect the side end of the RC beam 30 and the side end of the S beam 50. The RC beam 30 is an example of a first structural part, and the S beam 50 is an example of a second structural part. In the following description, the same configurations and procedures as those described in the previously described embodiments will be denoted by the same reference numerals, and their detailed descriptions will be omitted or simplified.

[0022] <Connection Structure> As shown in Figures 5 to 7, when RC columns 20 are provided both above and below the joint 61, the main reinforcement bars 21 of each RC column 20 should extend from the RC column 20 on the -Z side through the joint 61 along the Z direction and continue to the RC column 20 on the +Z side. In this case, the main reinforcement bars 21 of each RC column 20 extending to the +Z side of the joint 61 should be connected to the protruding portion 21a using a joint 25. Note that in Figure 7, for convenience, some stirrups 22 are omitted from the illustration.

[0023] Each main reinforcement bar 31 of the RC beam 30, located on the -X side of the joint 61, penetrates the joint 61 along the X direction and protrudes in the +X direction from the side end face 61b of the joint 61. The side end face 61b of the joint 61 is the side end of the RC beam 30. Of each main reinforcement bar 31, the portion that protrudes from the side end face 61b of the joint 61 is the protruding portion 31a.

[0024] A plate 42 is fixed to the side end of the steel beam 50. The plate 42 is located on the side end face 61b of the joint 61. The plate 42 is sized and shaped to cover all the positions where the main reinforcement bars 31 of the beam are arranged when viewed from the direction in which the reinforced concrete beam 30 to be connected extends (in this case, the X direction). Multiple through holes 43 are formed in the plate 42, penetrating along the X direction. A protruding portion 31a of the main reinforcement bar 31 is inserted through each through hole 43. A plate nut 44 is screwed onto each protruding portion 31a. In other words, the protruding portion 31a and the plate 42 are fastened together. Non-shrink mortar 45 is filled between the plate 42 and the side end face 61b of the joint 61.

[0025] <Connection Method> As shown in Figure 8, in step S200, each reinforcing bar is positioned and the formwork is formed. In step S200, each main beam reinforcement 31 is positioned along the X direction such that its +X side end protrudes from the side end face 61b of the joint 61. In step S210, concrete Cn is poured into the formwork. This forms the RC beam 30 and the protruding portion 31a.

[0026] In step S220, the steel beam 50 is installed. A plate 42 is fixed to the side end of the steel beam 50. The plate 42 is placed on the side end face 61b of the joint 61. The steel beam 50 is held in place by inserting the protruding portions 31a that protrude from the side end face 61b of the joint 61 through the insertion holes 43 formed in the plate 42. The steel beam 50 is temporarily fixed by screwing plate nuts 44 onto each protruding portion 31a.

[0027] In step S230, non-shrink mortar 45 is filled into the gap between the joint 61 and the plate 42. Furthermore, non-shrink mortar 45 is filled into the gaps between the protruding portion 31a and the insertion hole 43, and into the gaps between the plate 42 and the plate nut 44.

[0028] In step S240, the plate nuts 44 are tightened to fill the gaps between the joint 61 and the plate 42, the gaps between the protrusion 31a and the insertion hole 43, and the gaps between the plate 42 and the plate nuts 44 with non-shrink mortar 45. If necessary, the plate nuts 44 are further tightened to fix the plate 42 to the joint 61, i.e., the side end of the RC beam 30.

[0029] <Mechanism of Action and Effects> The operation and effects of this embodiment will now be described. (2-1) According to the connection structure 60, the main reinforcement bars 31 of the beam can also serve as anchor bolts, so there is no need to create additional space for anchor bolts. Therefore, the side end of the RC beam 30 and the side end of the S beam 50 can be easily connected.

[0030] (2-2) All of the main beam reinforcement 31 of the RC beam 30 to be connected are used as anchor bolts for connection to the S beam 50. Therefore, the strength of the connection structure 60 can be increased. <Example of changes> The above embodiment can be implemented with the following modifications. The above embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically.

[0031] As shown in Figure 9, some of the main beam reinforcements 31 of the RC beam 30 to be connected may also be used as anchor bolts. For example, the main beam reinforcements 31 as upper beam reinforcement may also be used as anchor bolts. On the other hand, if the main beam reinforcements 31 as lower beam reinforcement are not used as anchor bolts, it is advisable to provide multiple anchor bolts 65. Each anchor bolt 65 is inserted into an insertion hole 43 formed along the lower edge of the plate 42. According to this modification, the RC beam 30 and the S beam 50 can be connected even if the size and shape of the plate 42 do not cover all the positions where the main beam reinforcements 31 are located when viewed from the direction in which the RC beam 30 to be connected extends. The connection structure 60 connecting the RC column 20 and the S column 40 may also be modified so that some of the main column reinforcements 21 of the RC column 20 are used as anchor bolts. The size and shape of the plate 42 will vary depending on the shape of the S column 40 or S beam 50.

[0032] As shown in Figure 10, the building 10 may have a third floor section 13 that is continuous with the upper part of the second floor section 12 and includes one or more floors. The third floor section 13 is made of reinforced concrete (RC). The columns of the third floor section 13 are RC columns 20. The beams of the third floor section 13 are RC beams 30. Some of the multiple beams in the third floor section 13 may be steel beams 50. In this case, the connecting structure 60 may be configured to connect the lower end of the RC column 20 in the third floor section 13 to the upper end of the steel column 40 in the second floor section 12. For example, the steel column 40 constitutes the structure of the second floor section 12, and the RC column 20 constitutes the structure of the third floor section 13. In this case, the RC column 20 may be a precast RC column. Also, the protruding portion 21a may protrude in the -Z direction from the lower end surface of the joint 61. Then, the RC column 20 is erected by inserting the protruding portions 21a that protrude from the lower end surface of the joint 61 into each of the insertion holes 43 formed in the plate 42, and the plate nuts 44 are screwed into the protruding portions 21a.

[0033] If the RC beam 30 and S beam 50 to be connected are arranged along the same direction, other beams connected to the same joint 61 as these beams 30 and 50 are not limited to extending in a direction perpendicular to these beams 30 and 50.

[0034] Each floor section 11, 13 may be made of steel-reinforced concrete (SRC). In other words, the construction of each structural part constituting the connecting structure 60 by reinforced concrete is not limited to being made of RC, but also includes being made of SRC. The columns of each floor section 11, 13 may be SRC columns. The beams of each floor section 11, 13 may be SRC beams. For example, an SRC column may be constructed by embedding a steel frame extending along the Z direction in the RC column 20 described above, at a position surrounded by multiple main reinforcement bars 21. For example, an SRC beam may be constructed by embedding a steel frame extending along the horizontal direction in the RC beam 30 described above, at a position surrounded by multiple main reinforcement bars 31.

[0035] The RC columns 20 and RC beams 30 may be precast RC columns. In other words, the creation of the protrusions 21a and the formation of the protrusions 31a are not limited to being done at the construction site of the building 10, but may be done at a factory different from the construction site. [Explanation of Symbols]

[0036] Cn...Concrete, 10...Building, 11...First floor, 12...Second floor, 13...Third floor, 20...Reinforced concrete (RC) column, 21...Main column reinforcement, 21a...Protruding part, 22...Tie reinforcement, 25...Joint, 30...Reinforced concrete (RC) beam, 31...Main beam reinforcement, 31a...Protruding part, 32...Reinforcement, 33...Nut, 40...Steel (S) column, 42...Plate, 43...Through hole, 44...Plate nut, 45...Non-shrink mortar, 50...Steel (S) beam, 60...Connecting structure, 61...Joint, 61a...Upper end face, 61b...Side end face, 65...Anchor bolt.

Claims

1. A connecting structure between a first structural part made of reinforced concrete and a second structural part made of steel, The first structural part has a protruding portion from which the threaded reinforcing bar, which is the main reinforcement of the first structural part, protrudes from the end of the first structural part, and a plate located at the end of the first structural part to which the second structural part is fixed, A connecting structure in which the protruding portion and the plate are fastened together.

2. The first structural part and the second structural part are columns, The connection structure according to claim 1, wherein the end of the first structural part to which the second structural part is connected is the upper end of the first structural part.

3. The first structural part and the second structural part are columns, The connection structure according to claim 1, wherein the end of the first structural part to which the second structural part is connected is the lower end of the first structural part.

4. The first structural part and the second structural part are beams, The connection structure according to claim 1, wherein the end of the first structural part to which the second structural part is connected is the side end of the first structural part.

5. A method for connecting a first structural part made of reinforced concrete and a second structural part made of steel, The first structural part is formed with the threaded reinforcing bars, which are the main reinforcement of the first structural part, protruding from the end of the first structural part, and the threaded reinforcing bars form a protruding portion that extends from the end of the first structural part. A plate to which the second structural part is fixed is placed at the end of the first structural part, A connection method comprising fastening the protruding portion and the plate.

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