A column base plate closely adheres to a column foot of a pile top

Abstract

The utility model relates to a column foot structure of column bottom plate close to pile top, including steel column, bottom plate, the bottom plate is with steel column equal strength welding, is provided with long round hole matched with pile top longitudinal reinforcement in bottom plate corresponding position, makes the pile top longitudinal reinforcement can enter the steel column inside, the steel column has poured concrete in. The utility model through bottom plate and steel column equal strength welding, and set up long round hole matched with pile top longitudinal reinforcement precision on the bottom plate, fundamentally solved the problem that pile top longitudinal reinforcement and steel column bottom plate conflict, longitudinal reinforcement can not anchor into the problem of bearing platform, simultaneously through pouring concrete in the steel column, with the reliable anchoring system that enters the pile top longitudinal reinforcement formed, utilize the gripping force transmission tensile force of steel bar and concrete, construct steel column - concrete - pile integration force - transmission path, ensure that column bottom internal force direct, stable transmission, satisfy structure stress requirement, and the column foot required node board piece is few, need not to carry out the connecting design between board piece, reduce the node checking work load, and the construction is simple and convenient.

Description

Technical Field

[0001] This utility model relates to the field of building construction, specifically to a column base structure in which the column base plate is tightly attached to the top of the pile. Background Technology

[0002] With the rapid development of my country's social economy and construction technology, and the increasing demand for a better life, large-space buildings such as stadiums and exhibition centers are becoming more common, significantly improving people's quality of life. These large-space buildings require the use of long-span structural forms. These long-span structures (such as space frame structures and truss structures) are often supported on rectangular steel columns or rectangular steel-concrete composite columns (hereinafter referred to as "steel columns"). Some long-span structures have few stories (one or two stories) and small loads (only roof loads), resulting in relatively small axial forces transmitted to the bottom of the steel columns. When the bearing capacity of the soil near the bottom of the steel column is insufficient and pile foundations are required, and the bearing capacity of a single pile is large, a single pile can meet the bearing capacity requirements. In this case, the center of the pile coincides with the center of the steel column, and their dimensions are not significantly different. It is necessary to set appropriate column feet to effectively transfer the internal forces of the steel column and meet the calculation assumptions.

[0003] Traditional encased column bases involve placing the steel column base plate within the concrete cover of the foundation cap. The steel column transmits internal forces at its base to the foundation beams and piles via longitudinal reinforcement in the encased concrete, anchor bolts, and studs. However, due to the significant height of the concrete encasing the steel column, the foundation cap depth must be increased, raising construction costs. Furthermore, most of the bending moment at the base of the steel column is borne by the foundation beams, complicating the stress distribution on the foundation beams and making accurate calculations difficult. Connecting the steel column directly to the pile tops provides a more direct and reliable force transmission, eliminates the need for inter-component connection design, and reduces the workload of verification calculations. Utility Model Content

[0004] This utility model addresses the technical problems existing in the prior art by providing a column base structure in which the column base plate is tightly attached to the top of the pile.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A column base structure with the column base plate tightly attached to the pile top includes a steel column and a base plate. The base plate is welded to the steel column with equal strength. An elongated hole matching the longitudinal reinforcement of the pile top is opened at the corresponding position of the base plate, so that the longitudinal reinforcement of the pile top can pass into the interior of the steel column. The steel column is filled with concrete.

[0006] The beneficial effects of this utility model are: By welding the base plate to the steel column with equal strength and creating elongated holes on the base plate that precisely match the longitudinal reinforcement at the top of the pile, the problems of conflict between the longitudinal reinforcement at the top of the pile and the base plate of the steel column, and the inability of the longitudinal reinforcement to be anchored into the pile cap, are fundamentally solved. At the same time, by pouring concrete inside the steel column, a reliable anchoring system is formed with the inserted longitudinal reinforcement at the top of the pile. The bond force between the steel reinforcement and the concrete is used to transfer tensile force, constructing an integrated force transmission path of steel column-concrete-pile, ensuring direct and stable transmission of internal forces at the bottom of the column, and meeting the structural stress requirements. Moreover, fewer node plates are required at the column base, eliminating the need for connection design between plates and reducing the workload of node verification. Construction is also simple.

[0007] Furthermore, the steel column has a rectangular cross-section, and its lower part is encased in a concrete foundation. The foundation provides external constraints for the steel column, limiting its horizontal displacement and preventing local instability at the column base. At the same time, it diffuses the internal forces transmitted by the steel column to the pile body, thus completing the force transmission closed loop.

[0008] Furthermore, the steel column and the foundation are connected by studs. As the core shear-resistant component between the steel column and the foundation concrete, the studs, after being embedded in the foundation concrete, enhance the bond between the two and effectively prevent relative slippage between the steel column and the foundation.

[0009] Furthermore, concrete is poured inside the steel column up to above the top surface of the foundation. This ensures a seamless connection between the concrete inside the steel column and the concrete of the foundation, forming a continuous concrete load-bearing system and improving the overall integrity of the joint.

[0010] Furthermore, a stiffening plate is provided on the inner side of the steel column at the top of the foundation, and a casting hole is opened in the center of the stiffening plate. This can effectively enhance the local stiffness of the column base area, disperse the stress concentration at the bottom of the column, and prevent the steel column wall from deforming due to excessive local stress.

[0011] Furthermore, the vertical height from the lower surface of the base plate to the top surface of the foundation is not less than 2.5 times the length of the longer side of the steel column. This provides sufficient vertical constraint length for the coordinated force bearing of the steel column and the foundation.

[0012] Furthermore, a circular pouring hole is provided at the center of the base plate. This provides a core channel for pouring concrete into the steel column, ensuring that the concrete can be evenly filled from the bottom up, avoiding construction defects such as voids and honeycombing.

[0013] Furthermore, the length of the longitudinal reinforcement at the top of the pile extending into the steel column is not less than the anchorage length of the tension reinforcement. This meets the requirements of the "Code for Design of Concrete Structures" and ensures that the bond force between the reinforcement and the concrete is sufficient to transfer the tensile force of the pile.

[0014] Furthermore, the space between the upper surface of the pile top and the lower surface of the base plate is filled with grout of a strength grade no lower than that of the concrete inside the steel column. The gap between the pile top and the base plate is filled with grout, and the strength of the grout is no lower than that of the column concrete, which can completely fill the tiny gaps, avoid the pressure at the bottom of the column being concentrated in a local area, and protect the concrete of the base plate and the pile top. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model; Figure 2 for Figure 1 Sectional view in direction 1-1; Figure 3 This is a detailed drawing of the bottom opening in an embodiment of this utility model; The attached diagram lists the components represented by each number as follows: 1. Steel column, 2. Base plate, 3. Stud, 4. Grouting material, 5. Longitudinal reinforcement at the pile top, 6. Stiffening plate, 7. Pier cap, 8. Concrete. Detailed Implementation

[0016] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0017] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0018] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this technology based on the specific circumstances.

[0019] In the description of this application, spatial relation terms such as "below," "under," "below," "below," "above," "over," etc., are used herein to describe the relationship between one element or feature shown in the figures and other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figures is flipped, an element or feature described as "below" or "under" or "below" of other elements or features will be oriented "above" other elements or features. Therefore, the exemplary terms "below" and "under" 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 are interpreted accordingly.

[0020] In the description of this application, the term "for example" is used to mean "used as an example, illustration, or description." Any embodiment described as "for example" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to implement and use the present invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the present invention can be implemented without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the present invention with unnecessary detail. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0021] like Figures 1 to 3 As shown, this embodiment provides a column base structure where the column base plate 2 is tightly attached to the pile top, including a steel column 1 and a base plate 2. The base plate 2 is welded to the steel column 1 with equal strength. An elongated hole matching the longitudinal reinforcement 5 at the pile top is opened at the corresponding position of the base plate 2, allowing the longitudinal reinforcement 5 to pass into the interior of the steel column 1. Concrete 8 is poured inside the steel column 1. The purpose of this embodiment is to fundamentally solve the problems of conflict between the longitudinal reinforcement 5 at the pile top and the base plate 2, and the inability of the longitudinal reinforcement to be anchored into the pile cap 7, by welding the base plate 2 to the steel column 1 with equal strength and opening an elongated hole on the base plate 2 that precisely matches the longitudinal reinforcement 5 at the pile top; at the same time, by pouring concrete 8 inside the steel column 1, a reliable anchoring system is formed with the inserted longitudinal reinforcement 5 at the pile top, and the tensile force is transmitted by the bond force between the steel reinforcement and the concrete, constructing an integrated force transmission path of steel column-concrete-pile. This can not only fix the steel column, but also effectively transmit the axial force, bending moment and shear force at the bottom of the steel column, making the connection between the steel column and the pile reliable and safe, and meeting the structural stress requirements.

[0022] Specifically: The steel column 1 has a rectangular cross-section, and the lower part of the steel column 1 is encased in a concrete foundation 7. The rectangular cross-section can be adapted to the rectangular steel columns / rectangular steel tube concrete columns commonly used in large-span buildings, which fits the actual engineering application scenario; the foundation 7 provides external constraints for the steel column 1, restricts the horizontal displacement of the steel column 1, avoids local instability of the column base, and at the same time diffuses the internal force transmitted by the steel column 1 to the pile body, thus completing the force transmission closed loop.

[0023] The steel column 1 and the foundation 7 are connected by studs 3. As the core shear-resistant component of the concrete of the steel column 1 and the foundation 7, the studs 3 enhance the bond between the two after being embedded in the concrete of the foundation 7, effectively preventing relative slippage between the steel column 1 and the foundation 7; at the same time, they can improve the joint's resistance to horizontal force and bending moment, ensuring that the steel column 1 and the foundation 7 work together under horizontal loads (such as wind loads and seismic action), avoiding connection failure.

[0024] The concrete 8 inside the steel column 1 is poured up to the top surface of the pile cap 7. This ensures a seamless connection between the concrete inside the steel column 1 and the concrete in the pile cap 7, forming a continuous concrete 8 load-bearing system and improving the overall integrity of the joint. Moreover, the sufficient length of the concrete 8 can completely cover the longitudinal reinforcement 5 extending into the steel column 1, providing a reliable anchorage environment for the longitudinal reinforcement, ensuring that the anchorage length of the longitudinal reinforcement meets the requirements, and preventing the longitudinal reinforcement from being pulled out under tensile force.

[0025] A stiffening plate 6 is provided on the inner side of the steel column 1 at the top of the foundation 7, and a pouring hole is opened in the center of the stiffening plate 6. This can effectively enhance the local stiffness of the column base area, disperse the stress concentration at the bottom of the column, and prevent the steel column 1 wall from deforming due to excessive local stress. The pouring hole in the center of the stiffening plate 6 cooperates with the pouring hole in the base plate 2 to provide a smooth channel for pouring concrete 8 inside the steel column 1, ensuring that the concrete 8 can be filled densely and simplifying the construction operation.

[0026] The vertical height from the lower surface of the base plate 2 to the top surface of the pile cap 7 is not less than 2.5 times the length of the long side of the steel column 1. This provides sufficient vertical constraint length for the coordinated force bearing of the steel column 1 and the pile cap 7, ensuring a tight connection between the steel column 1 and the pile, making force transmission more reliable, and avoiding force transmission failure or structural vibration due to insufficient constraint length.

[0027] A circular pouring hole is provided at the center of the base plate 2. The pouring hole provides a core channel for pouring concrete 8 inside the steel column 1, ensuring that the concrete 8 can be filled evenly from the bottom up, avoiding construction defects such as voids and honeycomb; the pouring hole is centrally located, which facilitates the flow and diffusion of concrete 8, ensures the density of concrete 8 inside the steel column 1, and further improves the anchorage effect of longitudinal reinforcement and the load-bearing capacity of the joint.

[0028] The length of the longitudinal reinforcement 5 extending into the steel column 1 at the top of the pile is not less than the anchorage length La of the tensile reinforcement. This ensures that the bond force between the reinforcement and the concrete 8 is sufficient to transmit the tensile force of the pile; at the same time, it avoids the longitudinal reinforcement being pulled out due to insufficient anchorage length, ensuring that the tensile performance of the joint meets the design requirements, and improving the safety and durability of the structure under tensile force.

[0029] The space between the upper surface of the pile top and the lower surface of the base plate 2 is filled with grout 4 with a strength grade no lower than that of the concrete inside the steel column (which can be one grade higher). The gap between the pile top and the base plate 2 is filled with grout 4, and the strength of grout 4 is no lower than that of the column concrete grade 8. This grout 4 can completely fill the small gaps, avoid the pressure at the bottom of the column being concentrated in a local area, and protect the base plate 2 and the pile top concrete 8. At the same time, the grout 4 is tightly bonded to the base plate 2 and the pile top, forming a flat and dense force-transfer pad, which evenly diffuses the axial force at the bottom of the column to the pile top, ensuring stable pressure transmission and improving the reliability of the joint bearing capacity.

[0030] The working principle of the above structure: After on-site measurement and positioning of the longitudinal reinforcement of the piles, elongated holes are drilled at corresponding locations in the base plate 2 according to the longitudinal reinforcement positioning. A pouring hole is drilled in the center of the base plate 2. The steel column 1 plate, the drilled base plate 2, and the studs 3 are fabricated in the factory to form column foot joint components (factory fabrication of joint components ensures high quality and reduces on-site work). The column foot joint components are transported to the site, the longitudinal reinforcement of the piles is straightened, and the positioning of the holes in the base plate 2 is aligned with the positioning of the longitudinal reinforcement of the piles. The longitudinal reinforcement of the piles passes through the base plate 2 and enters the interior of the steel column 1, with the steel column 1 placed on top of the piles. After leveling the steel column 1 on-site, the space between the base plate 2 and the pile top is filled with grout 4 of a strength grade not lower than that of the column concrete 8, and then the pile cap 7 and the concrete 8 inside the steel column 1 are poured. The height from the bottom of the base plate 2 to the top surface of the pile cap 7 is not less than 2.5 times the length of the long side of the steel column 1.

[0031] While embodiments or examples of this disclosure have been described with reference to the accompanying drawings, it should be understood that the above embodiments are merely exemplary embodiments or examples, and the scope of this utility model is not limited by these embodiments or examples, but only by the granted claims and their equivalents. Various elements in the embodiments or examples may be omitted or replaced by their equivalents. Furthermore, the steps may be performed in a different order than that described in this disclosure. Further, various elements in the embodiments or examples may be combined in various ways. Importantly, as the technology evolves, many elements described herein can be replaced by equivalents that appear after this disclosure.

Claims

1. A column base structure with the column base plate tightly attached to the pile top, characterized in that, It includes a steel column and a base plate. The base plate is welded to the steel column with equal strength. An elongated hole matching the longitudinal reinforcement at the top of the pile is opened at the corresponding position of the base plate, so that the longitudinal reinforcement at the top of the pile can pass into the interior of the steel column. The steel column is filled with concrete.

2. The column base structure with the column base plate tightly attached to the pile top according to claim 1, characterized in that, The steel column has a rectangular cross-section, and its lower part is encased in a concrete foundation.

3. The column base structure with the column base plate tightly attached to the pile top according to claim 2, characterized in that, The steel column is connected to the foundation by studs.

4. A column base structure with the column base plate tightly attached to the pile top according to claim 2, characterized in that, The steel column is filled with concrete up to the top surface of the foundation.

5. A column base structure with the column base plate tightly attached to the pile top according to claim 2, characterized in that, A stiffening plate is provided on the inner side of the steel column at the top of the foundation, and a casting hole is opened in the center of the stiffening plate.

6. A column base structure with the column base plate tightly attached to the pile top according to claim 2, characterized in that, The vertical height from the lower surface of the base plate to the top surface of the foundation shall not be less than 2.5 times the length of the long side of the steel column.

7. A column base structure with the column base plate tightly attached to the pile top according to claim 1, characterized in that, A circular casting hole is provided at the center of the base plate.

8. A column base structure with the column base plate tightly attached to the pile top according to claim 1, characterized in that, The length of the longitudinal reinforcement at the top of the pile extending into the steel column shall not be less than the anchorage length of the tension reinforcement.

9. A column base structure with the column base plate tightly attached to the pile top according to claim 1, characterized in that, The space between the upper surface of the pile top and the lower surface of the base plate is filled with grout of a strength grade no lower than that of the concrete inside the steel column.

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