Panel core and column-beam connection structure

Abstract

To provide a panel core that reduces manufacturing costs by eliminating welding during production, offers superior quality and energy absorption, and a column-beam joint structure equipped with this panel core. [Solution] The panel core 10 that forms the panel zone of the column-beam joint structure is an integrally molded body made of cast iron or cast steel. The column-beam joint structure 100 has a panel core 10 (10F), steel columns 60A and 60B welded to the upper end 11 and lower end 12 of the panel core 10, and a steel beam 50 welded to the side surface 13 of the panel core 10.

Description

Technical Field

[0001] The present invention relates to a panel core and a column-beam joint structure.

Background Art

[0002] In the column-beam joint structure in a steel frame building having steel columns and steel beams, a panel zone is adopted in which a through diaphragm or an internal diaphragm is welded to a panel core made of a square steel pipe or the like. In the panel zone of the through diaphragm type or the internal diaphragm type, a square steel pipe of general specifications is often applied as the panel core.

[0003] On the other hand, a non-diaphragm type panel zone may be adopted, in which a panel core of a four-sided box manufactured by welding a plurality (for example, four) of steel plates having a larger thickness than that of a square steel pipe of general specifications without using diaphragms such as through diaphragms or internal diaphragms. According to this type of panel zone, it is possible to attach a steel beam without a diaphragm, and the design freedom can be increased as compared with the diaphragm type.

[0004] In panel zones where the aforementioned through diaphragms are applied, there are challenges such as the increased number of welds due to full penetration welding, which makes internal defect inspection time-consuming. Furthermore, in panel zones where an inner diaphragm is applied in addition to the outer diaphragm, there are challenges such as the welding position often being poor when welding the inner diaphragm inside the panel core, which easily leads to a decrease in welding quality. Moreover, when joining a steel beam made of H-shaped steel to the panel core, the upper and lower flanges of the steel beam made of H-shaped steel are welded to the upper and lower through diaphragms, and the web of the steel beam is welded to the side of the panel core (the flange of the panel core). In this structure, the upper and lower through diaphragms have high rigidity, so stress transmission from the upper and lower flanges of the steel beam is sufficient, but the flanges of the panel core do not have high resistance to out-of-plane bending, so stress transmission from the web of the steel beam is insufficient. As a result, in the design of steel beams welded to a panel core, it is not possible to consider the load-bearing capacity of the entire cross-section of the steel beam, including the upper and lower flanges and web (so-called full load-bearing capacity). The design of the beam ends of the steel beam is based only on the load-bearing capacity of the upper and lower flanges (reducing the load-bearing capacity during beam design), which can hinder the rational design of steel beams.

[0005] On the other hand, in the non-diaphragm type, which is a four-sided box panel core made of thick plates, the amount of steel used tends to be large. Although the number of fully penetration welds is reduced compared to the diaphragm type, thus reducing the effort required for welding, these two factors cancel each other out, making it difficult to reduce construction costs. Furthermore, from the perspective of structural performance, because the plate thickness of the panel core is thick, plastic deformation (panel collapse) in the panel zone is unlikely to occur, and its energy absorption capacity (e.g., seismic energy absorption capacity) tends to be lower than the energy absorption capacity of the entire steel frame due to both plastic deformation (beam yielding) at the beam ends of steel beams and panel collapse.

[0006] Therefore, by eliminating welding during manufacturing, it is possible to reduce manufacturing costs, and a panel core with superior quality and energy absorption, as well as a column-beam joint structure equipped with this panel core, are desirable.

[0007] Here, Patent Document 1 proposes a column-beam joint structure. This column-beam joint structure comprises a steel pipe column, an H-shaped steel beam welded to the outer surface of the steel pipe column, and at least one reinforcing steel joined to the outer surface of the steel pipe column between the flanges of the H-shaped steel beam. The steel pipe column comprises an intermediate steel pipe column, an upper steel pipe column, and a lower steel pipe column, with an upper diaphragm welded between the intermediate steel pipe column and the upper steel pipe column, and a lower diaphragm welded between the intermediate steel pipe column and the lower steel pipe column. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2024-90174 [Overview of the project] [Problems that the invention aims to solve]

[0009] The column-beam joint structure described in Patent Document 1 is also a diaphragm-type column-beam joint structure as described above, and therefore has the same problems as the diaphragm-type column-beam joint structure described above.

[0010] This invention has been made in view of the above problems, and aims to provide a panel core that can reduce manufacturing costs by eliminating welding during production, has excellent quality and energy absorption, and a column-beam joint structure equipped with this panel core. [Means for solving the problem]

[0011] To achieve the above objective, one embodiment of the panel core according to the present invention is: A panel core that forms a panel zone of a column-beam joint structure, It is characterized by being a single-piece molded body made of cast iron or cast steel.

[0012] According to this embodiment, since the panel core is a single molded body made of cast iron or cast steel, welding the panels together becomes unnecessary. As it is a single molded body, it has good manufacturability and excellent quality, and as a result of its high quality, it becomes a panel core with excellent energy absorption. In this embodiment, either cast iron or cast steel may be used as the manufacturing material.

[0013] In this specification, "panel core" includes not only simple forms consisting only of rectangular or cylindrical steel boxes that form a panel zone, but also forms in which diaphragms and vertical ribs, as described below, are integrally molded.

[0014] Furthermore, other embodiments of the panel core according to the present invention include: The through diaphragm located at the upper and / or lower end of the panel core is further integrally molded.

[0015] According to this embodiment, since the through diaphragm at the upper and / or lower end of the panel core is further integrally molded, the panel core with the through diaphragm can be manufactured without welding.

[0016] Furthermore, other embodiments of the panel core according to the present invention include: The internal diaphragm located inside the panel core is further integrally molded.

[0017] According to this embodiment, since the internal diaphragm located inside the panel core is further integrally molded, a panel core with a through diaphragm can be manufactured without welding.

[0018] Furthermore, other embodiments of the panel core according to the present invention include: The cross-shaped vertical ribs located inside the panel core are further integrally molded.

[0019] According to this aspect, by further integrally forming a cross-shaped vertical rib inside the panel core, a panel core with a cross-shaped vertical rib can be manufactured without welding.

[0020] Also, another aspect of the panel core according to the present invention is characterized in that any two or more of the through diaphragms at the upper end and / or lower end of the panel core, the inner diaphragms inside the panel core, and the cross-shaped vertical ribs inside the panel core are further integrally formed.

[0021] According to this aspect, by further integrally forming any two or more of the through diaphragms at the upper end and / or lower end of the panel core, the inner diaphragms, and the cross-shaped vertical ribs, a panel core including two or more of the through diaphragms, inner diaphragms, and vertical ribs can be manufactured without welding.

[0022] Here, this aspect includes forms including at least one of the upper and lower through diaphragms and the inner diaphragm, forms including at least one of the upper and lower through diaphragms and the vertical rib, forms including the inner diaphragm and the vertical rib, and forms including all of the at least one of the upper and lower through diaphragms, the inner diaphragm, and the vertical rib.

[0023] Also, another aspect of the panel core according to the present invention is characterized in that the inner diaphragm is inside the panel core, and the cross-shaped vertical rib is in the upper space and / or lower space of the inner diaphragm inside the panel core.

[0024] According to this aspect, by having an inner diaphragm inside the panel core and a cross-shaped vertical rib in the upper space and / or lower space of the inner diaphragm inside the panel core, for example, a panel core including the inner diaphragm and one or more vertical ribs can be manufactured without welding.

[0025] Also, in another aspect of the panel core according to the present invention, The panel core is characterized by having a rectangular or cylindrical shape, and includes forms in which the cross-sectional dimensions are uniform in the height direction of the panel core, and forms in which the cross-sectional dimensions change in the height direction of the panel core.

[0026] According to this embodiment, by having a rectangular or cylindrical shape, the panel core can be joined to steel columns made of rectangular steel pipes or steel pipes (cylindrical steel pipes) when forming a column-beam joint structure. Furthermore, this embodiment includes both a form in which the cross-sectional dimensions of the panel core are uniform in the height direction and a form in which the cross-sectional dimensions of the panel core change in the height direction. The former form can accommodate cases where the upper and lower steel columns have the same outer diameter, and the latter form can accommodate cases where the outer diameters of the upper and lower steel columns are different, thus becoming a so-called tapered core.

[0027] Furthermore, in another embodiment of the panel core according to the present invention, The cross-shaped vertical ribs are characterized in that their cross-section increases towards the end that is joined to the inner wall surface of the panel core.

[0028] According to this embodiment, the cross-shaped vertical ribs have a larger cross-section towards the end that is joined to the inner wall surface of the panel core. This allows the web of the steel beam and the vertical ribs to be aligned even if, for example, the web is slightly misaligned to the left or right from the center line (vertical center line) of the side of the panel core due to construction errors when the steel beam made of H-shaped steel is welded to the side (flange) of the panel core. This contributes to the formation of a column-beam joint structure that can effectively transmit bending and shear forces from the web of the steel beam to the vertical ribs, even when there are construction errors during the welding of the steel beam.

[0029] Furthermore, one embodiment of the column-beam joint structure according to the present invention is: The panel core and, The steel columns are welded to the upper and lower ends of the panel core, The panel core is characterized by having a steel beam welded to the side surface of the panel core.

[0030] According to this embodiment, since the column-beam joint structure is equipped with the panel core of the present invention, the number of welding points can be significantly reduced compared to conventional column-beam joint structures equipped with a panel core, and a column-beam joint structure with excellent quality and energy absorption can be formed with good manufacturability. [Effects of the Invention]

[0031] As can be understood from the above explanation, the panel core and column-beam joint structure of the present invention can reduce manufacturing costs by eliminating welding during production, and can provide a panel core with excellent quality and energy absorption, as well as a column-beam joint structure with excellent manufacturability and energy absorption. [Brief explanation of the drawing]

[0032] [Figure 1A] This is a perspective view of an example of a panel core according to the embodiment. [Figure 1B] This is a perspective view of another example of a panel core according to the embodiment. [Figure 1C] This is a perspective view of yet another example of a panel core according to the embodiment. [Figure 1D] This is a perspective view of yet another example of a panel core according to the embodiment. [Figure 2A] This is a perspective view of yet another example of a panel core according to the embodiment. [Figure 2B] This is a perspective view of yet another example of a panel core according to the embodiment. [Figure 2C] This is a perspective view of yet another example of a panel core according to the embodiment. [Figure 2D] This is a perspective view of yet another example of a panel core according to the embodiment. [Figure 3] This is a perspective view of an example of a column-beam joint structure according to the embodiment. [Figure 4] This is a view from arrow IV-IV in Figure 3. [Modes for carrying out the invention]

[0033] The panel core and column-beam joint structure according to the embodiment will be described below with reference to the attached drawings. In this specification and drawings, substantially identical components may be denoted by the same reference numerals to avoid redundant explanations.

[0034] [Panel core and column-beam joint structure according to the embodiment] An example of a panel core and column-beam joint structure according to the embodiment will be described with reference to Figures 1 to 4. Here, Figures 1A to 1D and Figures 2A to 2D are perspective views of an example of a panel core according to the embodiment. Figure 3 is a perspective view of an example of a column-beam joint structure according to the embodiment, and Figure 4 is a view taken along the line IV-IV in Figure 3.

[0035] The panel core 10 shown in Figure 1A is a panel core that forms the panel zone of a column-beam joint structure, and is a one-piece molded body made of cast iron or cast steel. The panel core 10 has a rectangular tubular shape with a hollow 15 and has uniform cross-sectional dimensions in the height direction.

[0036] In the illustrated example, the panel core 10 has a square outer shape (an example of a rectangle) in the cross-section perpendicular to the height direction, but the outer shape may be a rectangle other than a square (another example of a rectangle).

[0037] For example, conventional panel cores such as four-sided boxes are manufactured by welding together four steel plates of varying thicknesses, which requires welding time and carries the risk of performance degradation due to variations in welding quality. However, the panel core 10 shown in the illustration is a single molded body of cast iron or cast steel, allowing for the easy manufacture of panel cores of various thicknesses and heights, eliminating the need for welding and resulting in a high-quality panel core.

[0038] Unlike conventional panel cores, such as those made of square steel pipes, the illustrated panel core 10 is not a panel core with uniformly defined thicknesses for each steel plate, but rather an integrally molded body that can be formed to various thicknesses according to the required load-bearing capacity and panel collapse resistance during earthquakes. In terms of being able to accommodate various thicknesses, it is similar to a four-sided box, but as mentioned above, its structure differs significantly from a conventional four-sided box in that it eliminates the need for welding.

[0039] Since the panel core 10 has a uniform cross-sectional dimension in the height direction, in a column-beam joint structure equipped with the panel core 10, the outer diameter of the upper column (steel column) made of a rectangular steel pipe (not shown) welded to the upper end 11 of the panel core 10 and the outer diameter of the lower column (steel column) made of a rectangular steel pipe (not shown) welded to the lower end 12 of the panel core 10 are, for example, the same.

[0040] Furthermore, a steel beam made of H-shaped steel or the like (not shown) will be welded to at least one of the four sides 13.

[0041] Similar to a standard four-sided box-type panel core, the absence of a through diaphragm allows for greater design flexibility compared to diaphragm-type designs.

[0042] On the other hand, the panel core 10A shown in Figure 1B is a truncated pyramidal tapered core with a square cross-sectional shape in plan view and trapezoidal sides 13A, in order to accommodate the configuration in which the outer diameters of the upper and lower columns, which are made of square steel pipes (not shown) welded to the upper end 11 and lower end 12, differ.

[0043] In the illustrated example, the dimensions of the upper end 11 are smaller than those of the lower end 12. However, if the outer diameter of the upper column is larger than that of the lower column, the panel core 10A will be used upside down.

[0044] The panel core 10A is also a single-piece molded body made of cast iron or cast steel, and can be formed with various wall thicknesses and heights, and various trapezoidal side shapes 13A.

[0045] On the other hand, the panel core 10B shown in Figure 1C is a panel core that has a hollow 15 inside its cylindrical side surface 13B and has uniform cross-sectional dimensions in the height direction.

[0046] Panel core 10B is also a single-piece molded body made of cast iron or cast steel, and can be formed with various wall thicknesses, heights, inner diameters, and outer diameters.

[0047] The outer diameters of the upper column (steel column), which is made of a steel pipe (not shown) welded to the upper end 11 of the panel core 10B, and the lower column (steel column), which is made of a steel pipe (not shown) welded to the lower end 12 of the panel core 10B, are, for example, the same.

[0048] On the other hand, the panel core 10C shown in Figure 1D is a truncated conical tapered core with a circular, tapered side surface 13C in plan view, in order to accommodate a configuration in which the outer diameters of the upper and lower columns, which are made of steel pipes (not shown) welded to the upper end 11 and lower end 12, are different.

[0049] Panel core 10C is also a single-piece molded body made of cast iron or cast steel, and can be formed with various wall thicknesses, heights, inner diameters, and outer diameters.

[0050] On the other hand, the panel core 10D shown in Figure 2A is a single-piece molded body in which a rectangular tubular panel core 10 having uniform cross-sectional dimensions in the height direction and through diaphragms 20A and 20B at its upper end 11 and lower end 12 are formed from cast iron or cast steel.

[0051] For manufacturing, the panel core 10D can be produced by using an inner frame (not shown) that defines the outer shape around the hollow 15 and an outer frame that forms the outer shape of the panel core 10D shown in the example, and pouring cast iron or cast steel between the inner frame and the outer frame.

[0052] Panel core 10D is also a single-piece molded body made of cast iron or cast steel, and can be used to form rectangular tubular panel cores with various wall thicknesses and heights, as well as panel cores with through diaphragms of various planar dimensions.

[0053] Although not shown in the diagram, the panel core may also have a through diaphragm provided on only one side, either the top or bottom.

[0054] On the other hand, the panel core 10E shown in Figure 2B is a single-piece molded body in which a rectangular tubular panel core 10 having uniform cross-sectional dimensions in the height direction, through diaphragms 20A and 20B located at its upper end 11 and lower end 12, and an inner diaphragm 30 provided at an intermediate position in the hollow 15 are formed from cast iron or cast steel.

[0055] During manufacturing, the panel core 10E can be produced by utilizing an inner frame (not shown) which is fixed in place in the upper space 15A above the inner diaphragm 30 and the lower space 15B below it, and an outer frame which forms the outer shape of the panel core 10E as shown in the example, and pouring cast iron or cast steel between the inner frame and the outer frame.

[0056] In the panel core 10E, which is a single-piece molded body of cast iron or cast steel, it is possible to form rectangular tubular panel cores with various wall thicknesses and heights, panel cores with through diaphragms of various planar dimensions, and panel cores with internal diaphragms 30 at various height positions in the hollow 15 (for example, height positions corresponding to the position of the lower flange of a stepped beam made of H-shaped steel).

[0057] Although not shown in the illustration, the panel core may have a through diaphragm on only one side, either the top or bottom. Furthermore, although not shown in the illustration, the panel core may lack a through diaphragm and consist only of a rectangular tubular panel core 10 and an inner diaphragm 30.

[0058] On the other hand, the panel core 10F shown in Figure 2C is a single-piece molded body in which a rectangular tubular panel core 10 having uniform cross-sectional dimensions in the height direction, through diaphragms 20A and 20B at its upper end 11 and lower end 12, and a cross-shaped vertical rib 40 provided in the hollow 15 are formed from cast iron or cast steel.

[0059] During manufacturing, the panel core 10F can be produced by using an inner frame (not shown) that is fixed in place in the four internal spaces 15C of the cross-shaped vertical rib 40, and an outer frame that forms the outer shape of the panel core 10F as shown in the example, and pouring cast iron or cast steel between the inner and outer frames.

[0060] In the panel core 10F, which is a single-piece molded body of cast iron or cast steel, it is possible to form rectangular tubular panel cores with various wall thicknesses and heights, panel cores with through diaphragms of various planar dimensions, and panel cores with cross-shaped vertical ribs 40 of various wall thicknesses in the hollow 15.

[0061] Although not shown in the illustration, the panel core may have a through diaphragm on only one side, either the top or bottom. Furthermore, although not shown in the illustration, the panel core may lack a through diaphragm and consist only of a rectangular tubular panel core 10 and vertical ribs 40.

[0062] On the other hand, the panel core 10G shown in Figure 2D is a single-piece molded body formed from cast iron or cast steel, comprising a rectangular tubular panel core 10 having uniform cross-sectional dimensions in the height direction, through diaphragms 20A and 20B located at its upper end 11 and lower end 12, an inner diaphragm 30 provided at an intermediate position in the hollow 15, and cross-shaped vertical ribs 40 provided in both the upper space 15A above the inner diaphragm 30 and the lower space 15B below it.

[0063] In manufacturing, the panel core 10G can be produced by utilizing the four internal spaces 15C of the cross-shaped vertical rib 40 that form the upper space 15A, the four internal spaces 15C of the cross-shaped vertical rib 40 that form the lower space 15B, and the non-illustrated inner frames that are placed in each of these spaces, and the outer frame that forms the outer shape of the panel core 10G as shown in the illustrated example, and by pouring cast iron or cast steel between the inner and outer frames.

[0064] In the panel core 10G, which is a single-piece molded body of cast iron or cast steel, it is possible to form rectangular tubular panel cores with various wall thicknesses and heights, panel cores with through diaphragms of various planar dimensions, and panel cores with internal diaphragms 30 at various height positions in the hollow 15, and cross-shaped vertical ribs 40 of various wall thicknesses in the upper space 15A and the lower space 15B.

[0065] Although not shown in the illustration, the panel core may have a through diaphragm on only one side, either the top or bottom. Furthermore, although not shown in the illustration, the panel core may have a cross-shaped vertical rib 40 on only one side, either the top or bottom, of the inner diaphragm 30.

[0066] As described above, the panel cores 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10G shown in Figures 1A to 2D are all integrally molded from cast iron or cast steel, eliminating the need for welding the panels together. Because they are integrally molded, they offer excellent manufacturability and superior quality, and their high quality results in panel cores with excellent energy absorption.

[0067] Next, an example of a column-beam joint structure according to the embodiment will be described with reference to Figures 3 and 4. Here, the column-beam joint structure 100 in the illustrated example is a structure equipped with a panel core 10F having cross-shaped vertical ribs 40A, but it may also be a structure having other forms of panel cores as already described.

[0068] In the column-beam joint structure 100, the lower and upper ends of a steel column 60 made of square steel pipe are welded to the upper and lower through diaphragms 20 that form the panel core 10F, respectively. Furthermore, the web 51 of a steel beam 50 made of H-shaped steel is welded to the side surface 13 of the panel core 10F, and the upper flange 52 and lower flange 53 are welded to the upper and lower through diaphragms 20, respectively. In the illustrated example, the steel beam 50 is joined to a pair of opposing side surfaces 13 of the four side surfaces 13 of the panel core 10F, but it may also be joined to two mutually orthogonal side surfaces 13, to three side surfaces 13, or to all four side surfaces 13.

[0069] As clearly shown in Figure 4, the cross-shaped vertical rib 40A in the illustrated example has an enlarged end 42 that has a larger cross-section (having a thickness t2 that is larger than the thickness t1 of the general part) toward the end that is joined to the inner wall surface of the rectangular tubular panel core 10.

[0070] As described above, the cross-shaped vertical rib 40A has an enlarged end 42 that increases in cross-section towards the end that is joined to the inner wall surface of the panel core 10. This allows the web 51 of the steel beam 50, which is made of H-shaped steel, to be aligned with the vertical rib 40A even if the web 51 of the steel beam 50 is slightly misaligned in the X1 direction to the left or right from the center line L (vertical center line) of the side surface 13 of the panel core 10F due to construction errors when the steel beam 50 is welded to the side surface 13 of the panel core 10F. This contributes to the formation of a column-beam joint structure 100 that can effectively transmit the bending M and shear force S acting from the web 51 of the steel beam 50 to the vertical rib 40A, even if there are construction errors when the steel beam 50 is welded.

[0071] In this way, the cross-shaped vertical rib 40A is integrally built into the rectangular tubular panel core 10, and the vertical rib 40A and the web 51 of the steel beam 50 are aligned with each other. As a result, the stress transfer from the web 51 to the vertical rib 40A is significantly better compared to when the vertical rib 40A is not present.

[0072] For example, if there is no vertical rib 40A, the side surface 13 (flange) of the panel core does not have high resistance to out-of-plane bending. This makes it difficult to design the steel beam 50 while taking into account stress transfer from the web 51 of the steel beam 50, and it becomes impossible to estimate the load-bearing capacity of the entire cross-section of the steel beam 50. As a result, it may become necessary to reduce a portion of the load-bearing capacity of the entire cross-section of the beam when designing the beam ends of the steel beam 50.

[0073] In contrast, in the panel core 10F equipped with the vertical rib 40A shown in the illustration, the stress transfer from the web 51 to the vertical rib 40A is good. Therefore, in designing the steel beam 50 welded to the panel core 10F, it becomes possible to consider the load-bearing capacity of the entire cross-section of the steel beam 50, including the upper and lower flanges 52, 53 and the web 51, thereby enabling a rational design of the steel beam 50.

[0074] Furthermore, the column-beam joint structure 100 can achieve both plastic deformation at the beam ends of the steel beam 50 and plastic deformation in the integrally molded panel core 10F, thereby contributing to improving the energy absorption capacity of the entire steel frame structure.

[0075] Furthermore, other embodiments may be used in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited in any way to the configurations shown herein. In this regard, modifications can be made without departing from the spirit of the present invention, and can be appropriately determined according to the application form. [Explanation of Symbols]

[0076] 10: First panel core (panel core, integrally molded body) 10A: Second panel core (panel core, integrally molded body) 10B: Third panel core (panel core, integrally molded body) 10C: Fourth panel core (panel core, integrally molded body) 10D: Fifth panel core (panel core, integrally molded body) 10E: 6th panel core (panel core, integrally molded body) 10F: 7th Panel Core (Panel Core, Integrated Molded Body) 10G: 8th panel core (panel core, integrally molded body) 11:Top edge 12: Bottom edge 13,13A,13B,13C: Side 15:Hollow (inner space) 15A: Upper space 15B: Downward space 15C: Internal space 20, 20A, 20B: Through diaphragm 30: Internal diaphragm 40,40A: Vertical ribs 42: Enlarged end 50: Steel beam (H-shaped steel) 51: Web 52: Upper flange 53: Lower flange 60: Steel column 60A: Upper column (steel column) 60B: Lower column (steel column) 100: Column beam joint structure

Claims

1. A panel core that forms a panel zone of a column-beam joint structure, A panel core characterized by being a single-piece molded body made of cast iron or cast steel.

2. The panel core according to claim 1, characterized in that the through diaphragm located at the upper and / or lower end of the panel core is further integrally molded.

3. The panel core according to claim 1, characterized in that the internal diaphragm located inside the panel core is further integrally molded.

4. The panel core according to claim 1, characterized in that the cross-shaped vertical ribs located inside the panel core are further integrally molded.

5. The panel core according to claim 1, characterized in that two or more of the following are integrally molded: a through diaphragm located at the upper and / or lower end of the panel core, an internal diaphragm located inside the panel core, and a cross-shaped vertical rib located inside the panel core.

6. The panel core according to claim 5, characterized in that the internal diaphragm is located inside the panel core, and the cross-shaped vertical ribs are located in the space above and / or below the internal diaphragm inside the panel core.

7. The panel core according to claim 1, characterized in that the panel core is rectangular or cylindrical in shape, and includes a form having uniform cross-sectional dimensions in the height direction of the panel core and a form in which the cross-sectional dimensions change in the height direction of the panel core.

8. The panel core according to any one of claims 4 to 6, characterized in that the cross-shaped vertical ribs have a larger cross-section toward the end that is joined to the inner wall surface of the panel core.

9. A panel core according to any one of claims 1 to 7, The steel columns are welded to the upper and lower ends of the panel core, A column-beam joint structure characterized by having a steel beam welded to the side surface of the panel core.

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