Junction structure of reinforced concrete skeleton and steel column

Abstract

To effectively transfer force generated in a reinforced concrete skeleton to a steel column as axial force of the steel column.SOLUTION: A junction structure of a reinforced concrete skeleton and a steel column comprises: a skeleton made of reinforced-concrete; a steel column whose upper end portion is buried in the skeleton; and a protruding member which protrudes horizontally from the upper end portion buried in the skeleton in the steel column and has a supporting surface formed to receive a load from the skeleton.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a joint structure between a reinforced concrete body and a steel column. [Background technology]

[0002] In the method of joining a reinforced concrete beam to a steel column or a column equipped with steel frames described in Patent Document 1, after erecting the steel column, a steel plate with multiple reinforcing bar connection couplers fixed thereto is attached to the steel column via a diaphragm provided on the outer periphery of the steel column, and the main beam bars of the reinforced concrete beam are inserted into the reinforcing bar connection couplers to secure them in place. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-129426 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, in consideration of design, reinforced concrete structures are sometimes constructed on the upper ends of steel columns exposed to the outside.

[0005] The object of the present disclosure is to effectively transmit the force generated in a reinforced concrete skeleton to the steel column as an axial force of the steel column. [Means for solving the problem]

[0006] The joint structure between a reinforced concrete body and a steel column in the first embodiment comprises a reinforced concrete body, a steel column whose upper end portion is embedded in the body, and a protruding member that protrudes horizontally from the upper end portion of the steel column embedded in the body and has a bearing surface that receives the load from the body.

[0007] According to the above aspect, the protruding member protruding horizontally from the steel column is formed with a bearing surface that receives bearing pressure from the skeleton, thereby making it possible to effectively transmit the force generated in the reinforced concrete skeleton to the steel column as axial force of the steel column via the protruding member with the bearing surface formed thereon.

[0008] The second aspect of the joint structure between a reinforced concrete body and a steel column is the joint structure between a reinforced concrete body and a steel column described in the first aspect, wherein the body is a beam and a wall whose lower end is joined to the beam, and the protruding members are provided in pairs, each of which is embedded in the beam, and one of the protruding members and the other protruding member are positioned on opposite sides of the steel column.

[0009] According to the above-mentioned aspect, a pair of protruding members are embedded in the beam, and one protruding member and the other protruding member are disposed on opposite sides of the steel frame column. This makes it possible to effectively transmit the force generated in the reinforced concrete wall to the steel frame column as the axial force of the steel frame column through the beam and via the protruding member with the bearing surface formed thereon, compared to when the protruding member is disposed on only one side of the steel frame column.

[0010] The third aspect of the joint structure between a reinforced concrete body and a steel column is the joint structure between a reinforced concrete body and a steel column described in the first aspect, in which the protruding member is an H-shaped steel member, and the support surface is formed on a flange plate whose thickness direction is in the vertical direction.

[0011] According to the above aspect, bearing surfaces are formed on the flange plates whose thickness direction is the up-down direction, so that the bearing surface of the upper flange plate can receive the bearing pressure from the frame in the pressing direction, and the bearing surface of the lower flange plate can receive the bearing pressure from the frame in the pulling direction. [Effects of the Invention]

[0012] According to the present disclosure, the force generated in the reinforced concrete skeleton can be effectively transmitted to the steel column as axial force of the steel column. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view showing a reinforced concrete skeleton and a steel column in which a joint structure between a reinforced concrete skeleton and a steel column according to an embodiment of the present disclosure is adopted; [Figure 2] 1 is a perspective view showing a tip portion of a steel column that constitutes a joint structure between a reinforced concrete skeleton and a steel column according to an embodiment of the present disclosure. FIG. [Figure 3] 1 is a front view showing a joint structure between a reinforced concrete skeleton and a steel column according to an embodiment of the present disclosure. FIG. [Figure 4] 1 is a side view showing a joint structure between a reinforced concrete skeleton and a steel column according to an embodiment of the present disclosure. FIG. [Figure 5] 10 is a perspective view showing a tip portion of a steel column provided in a joint structure between a reinforced concrete skeleton and a steel column according to a modified embodiment of the present disclosure. FIG. [Figure 6] 10 is a perspective view showing a tip portion of a steel column provided in a joint structure between a reinforced concrete skeleton and a steel column according to a modified embodiment of the present disclosure. FIG. [Figure 7] FIG. 1 is a front view showing a joint structure between a reinforced concrete skeleton and a steel column according to a comparative example to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] An example of a joint structure between a reinforced concrete skeleton and a steel column according to an embodiment of the present disclosure will be described with reference to Figures 1 to 7. Arrow H shown in each figure indicates the vertical direction, which is the up-down direction of the structure in which the joint structure is used, arrow W shown in each figure indicates the width direction of the structure in which the joint structure is used, which is perpendicular to arrow H and also indicates the horizontal direction, and arrow D shown in each figure indicates the depth direction of the structure in which the joint structure is used, which is perpendicular to arrows H and W and also indicates the horizontal direction.

[0015] The drawings used in the following description are all schematic, and the dimensional relationships and ratios of elements shown in the drawings do not necessarily correspond to the actual ones.

[0016] (Overall composition) A connection structure 100 (hereinafter referred to as "connection structure 100") between a reinforced concrete skeleton and a steel column of this embodiment used in a structure 110 shown in Fig. 1 comprises a reinforced concrete skeleton 10 made of reinforced concrete including a reinforced concrete beam 20 and a reinforced concrete wall 30, and a steel column 40 with a circular cross section that extends in the vertical direction. Furthermore, as shown in Fig. 2, the connection structure 100 comprises a transmission member 50 for transmitting the force generated in the reinforced concrete skeleton 10 (see Fig. 1) to the steel column 40 as an axial force of the steel column 40.

[0017] [Reinforced concrete structure 10] As shown in FIG. 1 , the reinforced concrete skeleton 10 includes beams 20 extending in the width direction and walls 30 whose lower ends are joined to the beams 20. Specifically, the width of the beams 20 is wider than the thickness of the walls 30. Furthermore, the beams 20 and the walls 30 are eccentric, and the lower ends of the walls 30 are joined to the front portion of the beams 20 in the depth direction. The surface formed by the beams 20 and the walls 30 facing the front in the depth direction is flat. The reinforced concrete skeleton 10 is an example of a skeleton made of reinforced concrete.

[0018] [Steel column 40] The steel column 40 is supported by the foundation beam, and as shown in FIG. 1, extends in the vertical direction, with its upper end embedded in the beam 20.

[0019] As shown in Fig. 2, the steel column 40 is provided with a diaphragm 12. This diaphragm 12 is a through diaphragm that divides the interior of the steel column 40 in the vertical direction, and is arranged along the underside of the beam 20 as shown in Fig. 3. With the upper end portion of the steel column 40 embedded in the beam 20, the upper portion of the diaphragm 12 inside the steel column 40 is filled with concrete.

[0020] [Transmission member 50] As shown in Figures 2 and 3, the transmission member 50 is provided at the upper end portion of the steel column 40 embedded in the beam 20, and comprises a pair of diaphragms 52, a pair of protruding members 56, and a gusset plate 62.

[0021] The diaphragms 52 are outer diaphragms, and are provided as a pair spaced apart in the vertical direction, and have a rectangular shape extending in the depth direction when viewed from above. Each diaphragm 52 has a circular through-hole 52a formed therein, into which the steel column 40 is inserted. The portion of the diaphragm 52 on the near side in the depth direction relative to the through-hole 52a is longer than the portion of the diaphragm 52 on the far side in the depth direction relative to the through-hole 52a.

[0022] Furthermore, the gusset plate 62 is disposed between one diaphragm 52 of the portion elongated in the depth direction and the other diaphragm 52 of the portion elongated in the depth direction. The thickness direction of the gusset plate 62 is the width direction, and when viewed from the width direction, the gusset plate 62 has a rectangular shape extending in the vertical direction. The upper and lower ends of the gusset plate 62 are in contact with the diaphragm 52 and attached by welding. Furthermore, the side ends of the gusset plate 62 are in contact with the steel column 40 and attached by welding.

[0023] In addition, a pair of protruding members 56 are provided so as to sandwich the diaphragm 52 in the width direction when viewed from above. In other words, one protruding member 56 and the other protruding member 56 are arranged on opposite sides of the steel column 40. The protruding members 56 are H-beam steel members and extend in the width direction.

[0024] Specifically, the protruding member 56 is formed of a pair of flange plates 56a with the plate thickness direction being the up-down direction, and a web plate 56b disposed between the pair of flange plates 56a. The end faces of the flange plates 56a are in contact with and attached by welding to the end faces of the diaphragm 52. The end faces of the web plate 56b are in contact with and attached by welding to the circumferential surface of the steel column 40.

[0025] The upward-facing surface of flange plate 56a, which constitutes protruding member 56 and is arranged on the upper side, serves as bearing surface 58, which receives a load in the pressing direction from reinforced concrete skeleton 10. Furthermore, the downward-facing surface of flange plate 56a, which constitutes protruding member 56 and is arranged on the lower side, serves as bearing surface 60, which receives a load in the pulling direction from reinforced concrete skeleton 10.

[0026] Also, when viewed from the width direction, the protruding members 56 are arranged inside the stirrups 22 that constitute the beam 20, and are surrounded by the plurality of main reinforcements 24 that constitute the beam 20, as shown in FIG.

[0027] In this embodiment, as an example, when the diameter of the steel column 40 is 10, the length of the protruding member 56 is 22. Here, when the diameter of the steel column 40 is 10, the length of the protruding member 56 is preferably 10 to 30, and may be 5 to 40.

[0028] (action) Next, the operation of the joint structure 100 will be explained while comparing it with a comparative embodiment of a joint structure 200 between a reinforced concrete skeleton and a steel column (hereinafter referred to as "joint structure 200"). First, the differences between the joint structure 200 of the comparative embodiment and the joint structure 100 will be mainly explained.

[0029] As shown in Fig. 7, the steel column 240 of the connection structure 200 according to the comparative example is not provided with a diaphragm, but is provided with a lid 240a that closes the upper opening. The connection structure 200 is also not provided with a transmission member 50 (see Fig. 2). In this configuration, the inside of the steel column 240 is not filled with concrete from the top to the bottom, and is left hollow.

[0030] In the connection structure 200 according to the comparative embodiment, the force generated in the reinforced concrete skeleton 10 (the force acting on the reinforced concrete skeleton 10) is transmitted from the upper end portion of the steel column 240 embedded in the reinforced concrete skeleton 10 as an axial force of the steel column 240. Here, the connection structure 200 is not provided with a protruding member. In other words, a bearing surface that receives a load in a pressing direction from the reinforced concrete skeleton 10 and a bearing surface that receives a load in a pulling direction from the reinforced concrete skeleton 10 are not formed. For this reason, the force generated in the reinforced concrete skeleton 10 cannot be sufficiently transmitted to the steel column 240 as an axial force of the steel column 240.

[0031] In contrast to this, in the connection structure 100 shown in Figs. 2 and 3, the force generated in the reinforced concrete skeleton 10 (the force acting on the reinforced concrete skeleton 10) is transmitted as an axial force to the steel column 40 via a protruding member 56 provided at the tip of the steel column 40 of the reinforced concrete skeleton 10. Specifically, the load in the pressing direction from the reinforced concrete skeleton 10 is received by a bearing surface 58 formed on the protruding member 56 and transmitted to the steel column 40 as an axial force of the steel column 40. In addition, the load in the pulling direction from the reinforced concrete skeleton 10 is received by a bearing surface 60 formed on the protruding member 56 and transmitted to the steel column 40 as an axial force of the steel column 40.

[0032] (summary) As described above, the connection structure 100 is provided with bearing surfaces 58, 60 that receive the load from the reinforced concrete skeleton 10. Therefore, compared to the connection structure 200 according to the comparative example, the force generated in the reinforced concrete skeleton 10 is effectively transmitted to the steel column 40 as the axial force of the steel column 40.

[0033] Furthermore, in the joint structure 100, a pair of protruding members 56 are provided and embedded in the beam 20, with one protruding member 56 and the other protruding member 56 being arranged on opposite sides of the steel column 40. This allows the force generated in the wall 30 to be transmitted more effectively to the protruding member 56 via the beam 20 than when a protruding member is arranged on only one side of the steel column.

[0034] Furthermore, in the joint structure 100, the protruding member 56 is an H-shaped steel member, and bearing surfaces 58, 60 are formed on a flange plate 56a whose thickness direction is the up-down direction. This allows the bearing surface 58 to withstand a load in the pressing direction from the reinforced concrete skeleton 10, and the bearing surface 60 to withstand a load in the pulling direction from the reinforced concrete skeleton 10.

[0035] In the joint structure 100, the upper end portion of the steel column 40 is embedded in the linearly extending beam 20 of the reinforced concrete skeleton 10, so that a pair of protruding members 56 are arranged on both sides of the steel column 40, but when the upper end portion of the steel column 40 is embedded in an L-shaped portion of the reinforced concrete skeleton, one protruding member 56 may be arranged to extend in one direction (width direction) and the other protruding member 56 may be arranged to extend in another direction (depth direction) perpendicular to the one direction, as in the modified embodiment shown in Fig. 5. Furthermore, when the upper end portion of the steel column 40 is embedded in a T-shaped portion of the reinforced concrete skeleton, for example, a pair of protruding members 56 may be arranged on both sides of the steel column 40, and the other protruding member 56 may be arranged to extend to one side of the other direction perpendicular to the pair of protruding members 56 (the far side in the depth direction), as in the modified embodiment shown in Fig. 6. The diaphragm 152 used in the modified embodiment has a square shape when viewed from above.

[0036] In the joint structure 100, the upper end portion of the steel column 40 is embedded in the beam 20, and the upper portion of the diaphragm 12 inside the steel column 40 is filled with concrete. In other words, the upper end portion of the steel column 40 embedded in the beam 20 is filled with concrete. As a result, the load input to the upper end portion of the steel column 40 via the protruding member 56 is effectively transmitted to the entire steel column 40 as the axial force of the steel column 40.

[0037] Although the present disclosure has been described in detail with respect to a specific embodiment, it will be apparent to those skilled in the art that the present disclosure is not limited to such an embodiment and that various other embodiments are possible within the scope of the present disclosure. For example, in the above embodiment, the steel column 40 is cylindrical, but it may also be rectangular, have an H-shaped cross section, or the like.

[0038] In addition, in the above embodiment, two protruding members 56 are provided, but the number may be other than two.

[0039] Although not specifically described in the above embodiment, the thickness of the beam in the range where the protruding member 56 is arranged in the horizontal direction (beam depth) may be made thicker than the thickness of the beam in other parts. [Explanation of symbols]

[0040] 10 Reinforced concrete structure (an example of a reinforced concrete structure) 20 beams 30 Wall 40 Steel column 56 Protruding member 58 Bearing surface 60 Bearing surface 100 Joint structure (joint structure between reinforced concrete body and steel column)

Claims

1. Reinforced concrete structure and a steel column having an upper end portion embedded in the skeleton; a protruding member that protrudes horizontally from an upper end portion of the steel column embedded in the skeleton and has a bearing surface formed thereon to receive a load from the skeleton; A joint structure between a reinforced concrete body and steel columns.

2. The skeleton is a beam and a wall whose lower end is joined to the beam, a pair of the protruding members is provided, and the pair of the protruding members is embedded in the beam; The one protruding member and the other protruding member are arranged on opposite sides of the steel column. A joint structure between a reinforced concrete skeleton and a steel column according to claim 1.

3. The protruding member is an H-shaped steel member, and the bearing surface is formed on a flange plate whose plate thickness direction is the up-down direction. A joint structure between a reinforced concrete skeleton and a steel column according to claim 1.

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