Column leg structure

Abstract

To effectively transmit shear force received from a column member to a foundation beam, compared to a case in which the inside of a cylinder plate is opened downward.SOLUTION: A column leg structure includes: a base plate which is mounted on the lower end of a column member erected on a foundation beam, is mounted on a top face of the foundation beam, and is formed with a through hole to which an anchor bolt is inserted; a cylinder plate which is mounted on the lower face of the base plate and has a rectangular cylindrical shape when being viewed from below; a rib plate which is arranged inside the cylinder plate, whose the end face is brought into contact with the lower surface of the base plate, and the end face is brought into contact with one plate constituting the cylinder plate and the other plate opposed to the one plate; and a bottom plate which blocks the inside of the cylinder plate and is mounted on the cylinder plate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a column base structure. [Background technology]

[0002] The column base structure described in Patent Document 1 is a column base structure provided at the lower end of a column member that is erected on a foundation concrete, and comprises a plate-shaped base plate whose planar shape is formed to be larger than the horizontal cross-sectional shape of the column member and to whose upper surface the lower end of the column member is fixed, and a protrusion that has a cavity formed inside and an enclosed portion with an open lower end and is provided to protrude downward from the lower surface of the base plate, and the protrusion is embedded inside the foundation concrete so that its lower end is located below the surface of the foundation concrete. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-143444 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a conventional column base structure, a rib plate that is cross-shaped when viewed from below and a rectangular cylindrical plate that surrounds the rib plate are sometimes provided on the underside of the base plate, which is embedded in the foundation beam (foundation concrete). In this configuration, the inside of the cylindrical plate is open downward.

[0005] The objective of the present disclosure is to effectively transmit the shear force received from the column member to the foundation beam, compared to when the inside of the tubular plate is open downward. [Means for solving the problem]

[0006] The column base structure of the first embodiment is characterized in that it comprises a base plate attached to the lower end of a column member erected on a foundation beam, resting on the top surface of the foundation beam and having a through hole into which an anchor bolt is inserted, a tubular plate attached to the underside of the base plate and having a rectangular cylindrical shape when viewed from below, a rib plate arranged inside the tubular plate and having an end surface in contact with the underside of the base plate and an end surface in contact with one plate that constitutes the tubular plate and the other plate opposite the one plate, and a bottom plate that closes the inside of the tubular plate and is attached to the tubular plate.

[0007] According to the above-mentioned aspect, the horizontal external force received by one of the plates constituting the tubular plate is transmitted from the one plate to the other plate via the rib plate and the bottom plate. As a result, the shear force received by the column member is transmitted to the foundation beam by the entire column base structure, and the shear force received from the column member can be transmitted to the foundation beam more effectively than when the inside of the tubular plate is open downward.

[0008] The column base structure according to a second aspect is the column base structure according to the first aspect, characterized in that an end face of the bottom plate is in contact with a plate surface of the cylindrical plate.

[0009] According to the above-mentioned embodiment, the bottom plate is attached to the tube plate with the end face of the bottom plate in contact with the plate face of the tube plate. As a result, the bottom plate is effectively compressed by the force received from the tube plate, and the horizontal external force received by one plate is transmitted from one plate to the other plate via the rib plate and the bottom plate, compared to the case where the bottom plate is attached to the tube plate with the plate face of the bottom plate in contact with the end face of the tube plate. In other words, the shear force received from the column member can be effectively transmitted to the foundation beam, compared to the case where the bottom plate is attached to the tube plate with the plate face of the bottom plate in contact with the end face of the tube plate.

[0010] The column base structure according to a third aspect is the column base structure according to the first or second aspect, characterized in that an end face of the rib plate is in contact with a plate surface of the bottom plate.

[0011] According to the above aspect, the bottom plate is attached to the tubular plate with the end face of the rib plate in contact with the plate surface of the bottom plate. As a result, the axial force received by the column member is transmitted to the foundation beam via the rib plate and the bottom plate, and the axial force received from the column member can be transmitted to the foundation beam more effectively than when the bottom plate is attached to the tubular plate with the end face of the rib plate and the plate surface of the bottom plate spaced apart. Effect of the Invention

[0012] According to the present disclosure, the shear force received from the column member can be effectively transmitted to the foundation beam compared to when the inside of the tubular plate is open downward. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a perspective view showing a column base structure according to an embodiment of the present disclosure from below. [Diagram 2] 1A and 1B are plan views showing a column base structure according to an embodiment of the present disclosure. [Diagram 3] FIG. 2 is a side view showing a column base structure according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is an exploded perspective view showing a column base structure according to an embodiment of the present disclosure. [Diagram 5] 1A and 1B are process diagrams showing the construction process of a column base structure according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a side view showing the construction state of the column base structure according to the embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An example of a column base structure according to an embodiment of the present disclosure will be described with reference to Figures 1 to 6. Arrow H shown in each figure indicates the up-down direction, i.e., the vertical direction, arrow W shown in each figure indicates the width direction perpendicular to arrow H and also the horizontal direction, and arrow D shown in each figure indicates the depth direction perpendicular to arrows H and W and also the horizontal direction.

[0015] (Overall composition) 1, the column base structure 10 of this embodiment includes a base plate 20 attached to the lower end of a column 100 having a circular cross section, and a tubular plate 30 attached to the base plate 20 and having a rectangular tubular shape when viewed from below. Furthermore, the column base structure 10 includes a rib plate 40 disposed inside the tubular plate 30, and a bottom plate 50 that closes the inside of the tubular plate 30 from below. The column 100 is an example of a column member.

[0016] [Base plate 20] The base plate 20 is formed of a sheet metal member, and is rectangular when viewed from above as shown in Fig. 1 and Fig. 2(A)(B). The lower end of the pillar 100 is attached by welding to the upper surface 20a of the base plate 20. Furthermore, the end of a wing plate 102 that supports the pillar 100 from the outer circumferential surface of the pillar 100 is attached by welding to the upper surface 20a of the base plate 20.

[0017] Further, on the outer periphery of the base plate 20, a plurality of through holes 20b are formed, into which anchor bolts 112 (see FIG. 6) protruding upward from foundation beams 110 made of concrete are inserted.

[0018] [Cylinder plate 30] The cylindrical plate 30 is made of a sheet metal member and has a rectangular cylindrical shape when viewed from below as shown in Figures 1 and 2(B). The cylindrical plate 30 is attached to the lower surface 20c of the base plate 20 by welding.

[0019] Specifically, the cylindrical plate 30 includes a pair of plates 32 spaced apart in the width direction, with the plate thickness direction being the width direction, and a pair of plates 34 spaced apart in the depth direction, with the plate thickness direction being the depth direction. The plates 32 and 34 are rectangular and extend horizontally when viewed from the plate thickness direction. The plate thicknesses of the plates 32 and 34 are similar, and the plate thicknesses of the plates 32 and 34 are thinner than the plate thickness of the base plate 20.

[0020] Both ends of one plate 32 are attached by welding to one end of one plate 34 and one end of the other plate 34. Furthermore, both ends of the other plate 32 are attached by welding to the other end of one plate 34 and the other end of the other plate 34.

[0021] [Rib plate 40] The rib plate 40 is made of a sheet metal member, and is disposed inside the cylindrical plate 30 as shown in Fig. 1 and Fig. 2(B), and is cross-shaped when viewed from below. Furthermore, the upper end surface of the rib plate 40 facing upward is in contact with the lower surface 20c of the base plate 20. In other words, the upper end surface of the rib plate 40 facing upward is in metal-to-metal contact with the lower surface 20c of the base plate 20.

[0022] Specifically, the rib plate 40 includes a plate 42 whose width direction is the thickness direction, and a pair of plates 44 whose depth direction is the thickness direction and arranged to sandwich the plate 42. The plates 42, 44 are rectangular and extend horizontally when viewed from the thickness direction. The thickness of the plate 42 and the thickness of the plate 44 are similar, and the thickness of the plates 42, 44 is thinner than the thickness of the plates 32, 34.

[0023] One end of each of the pair of plates 44 is attached by welding to the surface of the plate 42. Furthermore, the other end of each of the pair of plates 44 is attached by welding to the surface of one plate 32 and the surface of the other plate 32. In other words, the end faces of the plates 44 constituting the rib plate 40 are in contact with one plate 32 and the other plate 32 facing the one plate 32 and are attached by welding.

[0024] In addition, both ends of the plate 42 are attached by welding to the plate surface of one plate 34 and the plate surface of the other plate 34, respectively. In other words, the end faces of the plates 42 constituting the rib plate 40 are in contact with one plate 34 and the other plate 34 facing the one plate 34, and are attached by welding, respectively.

[0025] [Bottom plate 50] The bottom plate 50 is made of a sheet metal member, and is disposed so as to close the inside of the tubular plate 30 from below, as shown in Fig. 1 and Fig. 3, and is rectangular when viewed from below. Furthermore, the end face of the bottom plate 50 contacts the plate surface of the lower end portion of the tubular plate 30. In other words, the bottom plate 50 is surrounded by the lower end portion of the tubular plate 30. Furthermore, the plate thickness of the bottom plate 50 is the same as the plate thicknesses of the plates 42, 44.

[0026] Specifically, the thickness direction of the bottom plate 50 is the up-down direction, and the end face of the bottom plate 50 is in contact with and attached by welding to the plate surface of the lower end portion of the tubular plate 30. Furthermore, the downward-facing lower end face of the rib plate 40 is in contact with and attached by welding to the upward-facing plate surface of the bottom plate 50.

[0027] (Assembly process) Next, a process for assembling the base plate 20, the tube plate 30, the rib plate 40, and the bottom plate 50 that constitute the column base structure 10 will be described.

[0028] First, as shown in Fig. 4, the tubular plate 30 is placed so that the plate surface of the lower end portion of the tubular plate 30 surrounds the end face of the bottom plate 50. Furthermore, the rib plate 40 is placed inside the tubular plate 30, and each member is attached by welding. Then, the members attached by welding are attached to the lower surface 20c of the base plate 20 by welding. Specifically, the upper end of the tubular plate 30 constituting the members attached by welding is attached to the lower surface 20c of the base plate 20 by welding.

[0029] (Construction method) Next, the construction process of the column base structure 10 will be described.

[0030] As shown in Fig. 5(A), a foundation beam 110 in which an anchor bolt 112 is embedded and a recess 110a is formed is constructed, and non-shrink mortar 116 is placed in the recess 110a. Furthermore, the bottom plate 50 is placed on the non-shrink mortar 116 while the anchor bolt 112 is inserted into the through hole 20b of the base plate 20 attached to the lower end of the column 100. In this manner, the level of the column base structure 10 is adjusted.

[0031] Furthermore, as shown in Fig. 5(B), concrete is poured into the recess 110a, and after the poured concrete hardens, a nut 120 is tightened onto the anchor bolt 112 as shown in Fig. 6. Note that the wing plate 102 is omitted from Figs. 5 and 6 so that the essential configuration can be easily understood.

[0032] In this manner, the pillar 100 is erected on the foundation beam 110 , and the base plate 20 attached to the lower end of the pillar 100 is placed on the top surface 110 b of the foundation beam 110 .

[0033] (Action, Summary) In the column base structure 10 described above, the end faces of the plates 44 constituting the rib plate 40 contact and are attached by welding to one plate 32 and the other plate 32 opposing the one plate 32. Also, the end faces of the plates 42 constituting the rib plate 40 contact and are attached by welding to one plate 34 and the other plate 34 opposing the one plate 34. Furthermore, the bottom plate 50 closes the inside of the cylindrical plate 30 and is attached to the cylindrical plate 30 by welding.

[0034] With this configuration, the shear force received by the column 100 is transmitted to the foundation beam 110 via the column base structure 10. Here, in the column base structure 10, a horizontal external force received by one of the plates 32, 34 constituting the tubular plate 30 is transmitted from one of the plates 32, 34 to the other plate 32, 34 via the rib plate 40 and the bottom plate 50. In other words, in the column base structure 10, the shear force received by the column 100 is transmitted to the foundation beam 110 by the entire column base structure 10. As a result, the shear force received from the column 100 can be transmitted to the foundation beam 110 more effectively than when the inside of the tubular plate is open downward.

[0035] In addition, in the column base structure 10, the bottom plate 50 is attached to the tubular plate 30 by welding with the end face of the bottom plate 50 in contact with the plate surface of the tubular plate 30. As a result, the bottom plate is compressed, and the horizontal external force received by one of the plates 32, 34 is transmitted from one of the plates 32, 34 to the other plate 32, 34 via the rib plate 40 and the bottom plate 50, compared to the case where the bottom plate is attached to the tubular plate by welding with the plate surface of the bottom plate in contact with the end face of the tubular plate. In this way, the shear force received from the column 100 can be transmitted to the foundation beam 110 more effectively than the case where the bottom plate is attached to the tubular plate by welding with the plate surface of the bottom plate in contact with the end face of the tubular plate.

[0036] In addition, in the column base structure 10, the axial force received by the column 100 is transmitted to the foundation beam 110 via the column base structure 10. Here, in the column base structure 10, the upper end surface of the rib plate 40 is in metal-to-metal contact with the base plate 20. Furthermore, the lower end surface of the rib plate 40 is attached by welding in a state of contact with the plate surface of the bottom plate 50. As a result, the axial force received by the column 100 is transmitted to the foundation beam 110 via the rib plate 40 and the bottom plate 50, and the axial force received from the column 100 can be transmitted to the foundation beam 110 more effectively than in the case where the lower end surface of the rib plate and the plate surface of the bottom plate are separated from each other.

[0037] Furthermore, in the column base structure 10, since there is no need to fill the inside of the tubular plate 30 with concrete, there is no need to provide an air hole in the portion of the base plate 20 surrounded by the tubular plate 30.

[0038] Although the present disclosure has been described in detail with respect to a specific embodiment, it is clear to those skilled in the art that the present disclosure is not limited to the embodiment, and various other embodiments are possible within the scope of the present disclosure. For example, in the above embodiment, the rib plate 40 is cross-shaped when viewed from below, but it may be, for example, a grid-like shape when viewed from below. Any shape that can form the cylindrical plate 30 and transmit horizontal force from one of the opposing plates 32, 34 to the other plate 32, 34 may be used.

[0039] Although not specifically described in the above embodiment, unevenness may be formed on the outer peripheral surfaces of the plates 32, 34 that constitute the tubular plate 30 to improve the bite of the tubular plate into the poured concrete.

[0040] Although not specifically described in the above embodiment, an uneven portion may be formed on the lower surface of the bottom plate 50, and part of the horizontal force may be transmitted from this uneven portion to the foundation beam. [Explanation of symbols]

[0041] 10 Pillar base structure 20 Base Plate 20b Through hole 30 Cylinder Plate 32 Plate 34 Plate 40 Rib Plate 50 Bottom Plate 100 Pillar (an example of a pillar component) 110 Foundation beam 110b top surface 112 Anchor bolt

Claims

1. A base plate is attached to a lower end of a column member erected on a foundation beam, placed on a top surface of the foundation beam, and having a through hole into which an anchor bolt is inserted; a cylindrical plate attached to a lower surface of the base plate and having a rectangular cylindrical shape when viewed from below; a rib plate disposed inside the cylindrical plate, with an end surface in contact with a lower surface of the base plate, and with an end surface in contact with one plate constituting the cylindrical plate and the other plate opposed to the one plate; a bottom plate that closes the inside of the cylindrical plate and is attached to the cylindrical plate; A column base structure equipped with:

2. The end surface of the bottom plate is in contact with the plate surface of the cylindrical plate. The column base structure according to claim 1 .

3. The end surface of the rib plate is in contact with the plate surface of the bottom plate. The column base structure according to claim 1 .

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