Steel tube reinforced concrete column and column cap connecting joint for reducing the effect of void and construction method thereof

Abstract

This invention relates to a connection node and construction method for reducing the impact of voids between the concrete-filled steel tube column and the column cap. The connection node includes: a column cap; a steel pipe passing through and connected to the column cap; concrete filling the steel pipe; and a shear force transfer member disposed within the steel pipe and embedded in the concrete, with the shear force transfer member partially passing through the steel pipe wall and connected to the column cap. The shear force transfer member can move axially relative to the steel pipe, suitable for transferring part of the load of the column cap to the concrete inside the pipe. During the shrinkage and creep of the concrete inside the pipe, the shear force transfer member moves axially relative to the steel pipe along with the concrete inside the pipe. This application effectively alleviates the problem of reduced load-bearing capacity and stiffness caused by the concrete inside the concrete tube column becoming voided from the inner wall of the steel pipe due to years of shrinkage and creep, resulting in the concrete being unable to directly bear force.

Description

Technical Field

[0001] This invention relates to the field of building structures, and specifically to a connection node and construction method for reducing the impact of voids between steel tube concrete columns and column caps. Background Technology

[0002] The application of concrete-tube steel columns is becoming increasingly widespread in building structures. However, inspections of already operational concrete-tube steel columns revealed a common problem of voids between the concrete and the inner wall of the steel tube. This results in most of the structural weight load being transferred downwards through the steel tube, while the concrete in the core area is not directly stressed, thus its load-bearing capacity cannot be fully utilized. This deviates significantly from the theoretical assumption of shared load-bearing, leading to potential safety hazards in concrete-tube steel column structures calculated using current methods. Summary of the Invention

[0003] Based on the above description, the present invention provides a connection node and construction method for steel-concrete composite columns and column caps to reduce the impact of voids, in order to solve the problem that voids between concrete and the inner wall of steel tubes in steel-concrete composite members cause most of the structural gravity load to be transmitted downward through the steel tubes, while the concrete in the core area is not directly stressed. The bearing capacity of the concrete part cannot be fully utilized, which is significantly different from the theoretical assumption of joint stress, resulting in safety hazards in steel-concrete composite column structures calculated by existing calculation methods.

[0004] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0005] Firstly, this application provides a connection node between a steel-concrete composite column and a column cap to reduce the impact of voids, and the technical solution adopted is as follows:

[0006] A connection node between a steel-concrete composite column and a column cap to reduce the impact of voids, comprising:

[0007] Column cap;

[0008] A steel pipe that passes through and is connected to the column cap;

[0009] Concrete is used to fill the inside of the steel pipe;

[0010] A shear force transfer element is disposed inside the steel pipe and embedded in the concrete inside the pipe. The shear force transfer element partially passes through the wall of the steel pipe and is connected to the column cap. The shear force transfer element can move axially relative to the steel pipe and is suitable for transferring part of the load of the column cap to the concrete inside the pipe through the shear force transfer element.

[0011] in,

[0012] During the shrinkage and creep of the concrete inside the pipe, the shear force transmission component moves relative to the steel pipe along the axial direction of the steel pipe along with the concrete inside the pipe.

[0013] Preferably, the shear force transmission component includes multiple shear force transmission plates, the plane of which is parallel to the axis of the steel pipe. The multiple shear force transmission plates are interconnected inside the steel pipe. Multiple axially extending vertical slits are formed on the wall of the steel pipe. The multiple vertical slits are spaced apart circumferentially along the steel pipe. The multiple shear force transmission plates extend through the multiple vertical slits to the outside of the steel pipe and are connected to the column cap. The bottom of the shear force transmission plate is spaced apart from the steel pipe axially.

[0014] Preferably, the steel pipe is fitted with a sleeve coaxial with it, the sleeve is embedded in the column cap, and the plurality of shear force transfer plates are all connected to the sleeve.

[0015] Preferably, the sleeve covers multiple vertical slits, and multiple shear force transfer plates are located inside the sleeve in the axial direction of the steel pipe.

[0016] Preferably, the shear force transfer plate includes a main body located inside the steel pipe and a connecting part passing through the vertical joint. The length of the connecting part along the axial direction of the steel pipe is less than the length of the vertical joint, and the length of the main body along the axial direction of the steel pipe is greater than the length of the connecting part along the axial direction of the steel pipe.

[0017] Preferably, the shear force transfer plate is provided with a plurality of shear studs embedded in the concrete inside the pipe.

[0018] Preferably, the outer wall of the sleeve is connected with a plurality of shear studs embedded in the column cap.

[0019] Secondly, this application provides a construction method for the connection node between a steel tube concrete column and a column cap that reduces the impact of voids, comprising: setting the spacing between the bottom of the shear transfer plate and the steel tube in the axial direction of the steel tube according to the estimated shrinkage of the concrete inside the tube, so that there is always a spacing between the bottom of the shear transfer plate and the steel tube in the axial direction of the steel tube during the shrinkage and creep of the concrete inside the tube.

[0020] Compared with the prior art, the technical solution of this application has the following beneficial technical effects:

[0021] This application utilizes a shear force transfer component, which is installed inside a steel pipe and embedded in the concrete within the pipe. The component partially penetrates the pipe wall and connects to the column cap. This shear force transfer component transfers a portion of the column cap's load to the concrete inside the pipe. The shear force transfer component can move axially relative to the steel pipe, and during the shrinkage and creep of the concrete inside the pipe, it moves axially relative to the steel pipe along with the concrete. Throughout this process, the shear force transfer component consistently transfers a portion of the column cap's load to the concrete inside the pipe, preventing the concrete from failing to contact the pipe wall after shrinkage and creep, thus avoiding the situation where the entire load is applied to the steel pipe. This effectively alleviates the problem of reduced load-bearing capacity and stiffness caused by the concrete inside the steel-concrete composite column becoming detached from the inner wall of the steel pipe due to years of shrinkage and creep, resulting in the concrete being unable to directly bear force. Attached Figure Description

[0022] Figure 1 This is a structural schematic diagram of the connection node between the steel-concrete composite column and the column cap to reduce the impact of voids, provided in an embodiment of the present invention.

[0023] Figure 2 for Figure 1 A cross-sectional view along line AA in the middle;

[0024] Figure 3 A schematic diagram of the steel pipe and vertical joint in the connection node between the steel-concrete composite column and the column cap to reduce the impact of voids, provided in an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of the connection between the shear transfer plate and the sleeve in the connection node between the steel-concrete composite column and the column cap to reduce the impact of voidage, provided in an embodiment of the present invention.

[0026] Figure 5 for Figure 4 A cross-sectional view along line BB.

[0027] The attached diagram lists the components represented by each number as follows:

[0028] 1. Column cap; 2. Steel pipe; 21. Vertical joint; 3. Concrete inside the pipe; 4. Shear transfer plate; 41. Main body; 42. Connection part; 5. Sleeve; 6. Shear stud. Detailed Implementation

[0029] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0031] It is understood that spatial relation terms such as "below," "under," "below," "below," "above," "above," etc., can be used here to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, the element or feature described as "below" or "below" of the other element or feature will be oriented "above" the other element or feature. Therefore, the exemplary terms "below" and "below" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein will be interpreted accordingly.

[0032] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. In the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have the transmission of electrical signals or data between them.

[0033] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0034] Reference Figure 1-5 As shown in the embodiment of this application, a connection node between a steel-concrete composite column and a column cap to reduce the impact of voids is provided. It includes a column cap 1, a steel pipe 2, concrete 3 inside the pipe, and a shear force transfer component. The steel pipe 2 passes through and connects to the column cap 1, and the concrete 3 fills the interior of the steel pipe 2. The steel-concrete composite column is a column structure, a vertical member, and its specific cross-sectional shape can be circular, rectangular, or polygonal, designed according to needs to ensure structural stability. In this embodiment, the steel pipe 2 is illustrated with a rectangular cross-section. The column cap 1 can also be a horizontal member such as a flat slab.

[0035] The shear force transfer element is located inside the steel pipe 2 and embedded in the concrete 3 inside the pipe. The shear force transfer element partially passes through the wall of the steel pipe 2 and connects to the column cap 1. The shear force transfer element can move axially relative to the steel pipe 2, suitable for transferring the load of the column cap 1 to the concrete 3 inside the pipe. During the shrinkage and creep of the concrete 3 inside the pipe, the shear force transfer element moves axially relative to the steel pipe 2 along with the concrete 3 inside the pipe, ensuring that the shear force transfer element can always transfer part of the load of the column cap to the concrete inside the pipe.

[0036] Reference Figure 1-3 As shown, specifically, the shear force transmission component includes multiple shear force transmission plates 4. The plane of the shear force transmission plates 4 is parallel to the axis of the steel pipe 2. The multiple shear force transmission plates 4 are interconnected inside the steel pipe 2. Multiple axially extending vertical slits 21 are opened on the wall of the steel pipe 2. The multiple vertical slits 21 are spaced apart along the circumference of the steel pipe 2. The multiple shear force transmission plates 4 extend through the multiple vertical slits 21 to the outside of the steel pipe 2 and are connected to the column cap 1. The bottom of the shear force transmission plates 4 is spaced apart from the steel pipe 2 along the axial direction of the steel pipe 2. In this embodiment, a vertical slit 21 is provided on each of the four sides of the rectangular steel pipe 2. Correspondingly, there are four shear force transmission plates 4. The four shear force transmission plates 4 are perpendicular to the four side walls of the steel pipe 2. The four shear force transmission plates 4 intersect the axis of the steel pipe 2 inside the steel pipe 2 and are welded and fixed. The four shear force transmission plates 4 pass through the four vertical slits 21 respectively.

[0037] Reference Figure 1 and Figure 3-5 As shown, in order to transfer the pressure along the axial direction of the steel pipe 2 borne by the shear force transfer plate 4 to the concrete 3 inside the pipe, the shear force transfer plate 4 is configured to include a main body 41 located inside the steel pipe 2 and a connecting part 42 passing through the vertical joint 21. The length of the connecting part 42 along the axial direction of the steel pipe 2 is less than the length of the vertical joint 21, and the length of the main body 41 along the axial direction of the steel pipe 2 is greater than the length of the connecting part 42 along the axial direction of the steel pipe 2. In this way, when the shear force transfer plate 4 passes through the vertical joint 21, a gap can be left between the shear force transfer plate 4 and the steel pipe 2 in the axial direction, so that the shear force transfer plate 4 can be subjected to force and transferred to the concrete 3 inside the pipe.

[0038] Reference Figure 1 and Figure 3-5 As shown, further, to achieve the connection between the shear force transfer plate 4 and the column cap 1, a sleeve 5 coaxial with it is provided on the outer sleeve of the steel pipe 2. The sleeve 5 is embedded in the column cap 1, and multiple shear force transfer plates 4 are connected to the sleeve 5. Specifically, the connecting part 42 of the shear force transfer plate 4 passes through the vertical joint 21 and is welded and fixed to the inner wall of the sleeve 5. When designing the position of the vertical joint 21 and the shear force transfer plate 4, the design is based on the position of the column cap 1, so that the vertical joint 21 and the shear force transfer plate 4 are located in the column cap 1 in the axial direction of the steel pipe 2. Correspondingly, the sleeve 5 covers multiple vertical joints 21, and multiple shear force transfer plates 4 are located in the sleeve 5 in the axial direction of the steel pipe 2, so that the load of the column cap 1 can be smoothly transferred to the concrete 3 inside the pipe through the sleeve 5 and the shear force transfer plate 4.

[0039] Reference Figure 1 and Figure 3-5 As shown, further, in order to improve the connection stability between the shear force transfer plate 4 and the concrete 3 inside the pipe, the shear force transfer plate 4 is provided with a number of shear studs 6 embedded in the concrete 3 inside the pipe. In order to improve the connection strength between the sleeve 5 and the column cap 1, a number of shear studs 6 embedded in the column cap 1 are connected to the outer wall of the sleeve 5. The axis of the shear studs is perpendicular to the axis of the steel pipe 2. In this way, a stable connection and force transmission between the column cap 1, the steel pipe 2 and the concrete 3 inside the pipe can be achieved through the shear studs 6.

[0040] Since the length of the connecting part 42 of the shear force transfer plate 4 along the axial direction of the steel pipe 2 is less than the length of the vertical joint 21, the shear force transfer plate 4 can move relative to the steel pipe 2 along the axial direction of the steel pipe 2 within the vertical joint 21. Before pouring the concrete 3 inside the pipe and the column cap 1, the shear force transfer plate 4 is raised and temporarily fixed during installation, so that when the concrete 3 inside the pipe is poured and solidified, there is a gap between the bottom of the shear force transfer plate 4 and the steel pipe 2 along the axial direction. This ensures a stable connection between the shear force transfer plate 4 and the concrete 3 inside the pipe, and ensures that the shear force transfer plate 4 can stably transfer the load of the column cap 1 to the concrete 3 inside the pipe.

[0041] Specifically, the width of the vertical joint 21 needs to be slightly larger than the thickness of the shear force transfer plate 4 so that the shear force transfer plate 4 can move smoothly along the axial direction of the steel pipe 2 within the vertical joint 21; the inner diameter of the sleeve 5 is slightly larger than the outer diameter of the steel pipe 2 so that the sleeve 5 can move smoothly along the axial direction of the steel pipe 2 with the shear force transfer plate 4.

[0042] This application also provides a method for constructing the connection node between the steel-concrete composite column and the column cap to reduce the impact of voids, including the following steps:

[0043] S1: Based on the set number of shear transfer plates 4 and the corresponding position of the vertical seam 21 on the wall of steel pipe 2, a vertical seam 21 is opened at the corresponding position on the wall of steel pipe 2.

[0044] S2: Install shear force transfer plates 4, pass multiple shear force transfer plates 4 one by one through multiple vertical seams 21, and weld and fix multiple shear force transfer plates 4 inside steel pipe 2.

[0045] S3: Welded sleeve 5 and shear stud 6.

[0046] S4: Based on the estimated compression of the concrete 3 inside the steel tube in the concrete-filled steel tube column, the sleeve 5 and the shear transfer plate 4 are raised and temporarily fixed so that there is a gap between the bottom of the shear transfer plate 4 and the steel tube 2 in the axial direction of the steel tube 2, and ensure that there is always a gap between the bottom of the shear transfer plate 4 and the steel tube 2 in the axial direction of the steel tube 2 during the shrinkage and creep of the concrete 3 inside the tube.

[0047] S5: Complete construction procedures such as rebar tying and formwork construction.

[0048] S6: Concrete inside the steel-concrete composite column 3 and column cap 1, or concrete for flat slabs.

[0049] This application uses shear transfer plate 4, sleeve 5 and shear studs 6 to transfer most of the load of horizontal components such as column cap 1 to the concrete 3 inside the steel tube column, which can effectively alleviate the problem of reduced bearing capacity and stiffness caused by the separation of the concrete 3 inside the steel tube column from the inner wall of the steel tube 2 due to the inability of the concrete 3 inside the steel tube column to directly bear the force.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A connection node between a steel-concrete composite column and a column cap to reduce the impact of voids, characterized in that, include: Column cap (1); A steel pipe (2) passes through the column cap (1) and is connected to the column cap (1); Concrete (3) is filled inside the steel pipe (2); A shear force transfer member is provided inside the steel pipe (2) and embedded in the concrete (3) inside the pipe. The shear force transfer member partially passes through the wall of the steel pipe (2) and is connected to the column cap (1). The shear force transfer member can move relative to the steel pipe (2) in the axial direction. It is suitable for transferring part of the load of the column cap (1) to the concrete (3) inside the pipe through the shear force transfer member. The shear force transmission component includes multiple shear force transmission plates (4), the plane of the shear force transmission plate (4) is parallel to the axis of the steel pipe (2), the multiple shear force transmission plates (4) are connected to each other inside the steel pipe (2), multiple vertical slits (21) extending axially are opened on the wall of the steel pipe (2), the multiple vertical slits (21) are spaced apart circumferentially along the steel pipe (2), the multiple shear force transmission plates (4) extend through the multiple vertical slits (21) one by one to the outside of the steel pipe (2) and are connected to the column cap (1), and the bottom of the shear force transmission plate (4) is spaced apart from the steel pipe (2) axially; The steel pipe (2) is fitted with a sleeve (5) coaxial with it, the sleeve (5) is embedded in the column cap (1), and the multiple shear force transmission plates (4) are all connected to the sleeve (5); The shear force transfer plate (4) includes a main body (41) located inside the steel pipe (2) and a connecting part (42) passing through the vertical joint (21). The length of the connecting part (42) along the axial direction of the steel pipe (2) is less than the length of the vertical joint (21), and the length of the main body (41) along the axial direction of the steel pipe (2) is greater than the length of the connecting part (42) along the axial direction of the steel pipe (2). in, During the shrinkage and creep of the concrete (3) inside the pipe, the shear force transmission component moves relative to the steel pipe (2) along the axial direction of the steel pipe (2) along with the concrete (3) inside the pipe.

2. The connection node between the steel-concrete composite column and the column cap for reducing the impact of voids as described in claim 1, characterized in that: The sleeve (5) covers multiple vertical slits (21), and multiple shear transfer plates (4) are located inside the sleeve (5) in the axial direction of the steel pipe (2).

3. The connection node between the steel-concrete composite column and the column cap for reducing the impact of voids as described in claim 1, characterized in that: The shear transfer plate (4) is provided with a plurality of shear studs (6) embedded in the concrete (3) inside the pipe.

4. The connection node between the steel-concrete composite column and the column cap for reducing the impact of voids as described in claim 1, characterized in that: The outer wall of the sleeve (5) is connected to a plurality of shear studs (6) embedded in the column cap (1).

5. A method for constructing a connection node between a steel-concrete composite column and a column cap to reduce the impact of voids, as described in any one of claims 1-4, characterized in that... include: The spacing between the bottom of the shear transfer plate (4) and the steel pipe (2) in the axial direction of the steel pipe (2) is set according to the estimated shrinkage of the concrete (3) in the pipe, so that there is always a gap between the bottom of the shear transfer plate (4) and the steel pipe (2) in the axial direction of the steel pipe (2) during the shrinkage and creep of the concrete (3) in the pipe.

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