Self-resetting semi-rigid energy-consuming combined beam-column joint with shape memory alloy

Abstract

The invention relates to a self-resetting semi-rigid energy-consuming combined beam-column joint with shape memory alloy. The self-resetting semi-rigid energy-consuming combined beam-column joint comprises a concrete-filled steel tube column; the steel beam is arranged on the side of the concrete-filled steel tubular column; the concrete floor is arranged at the top of the steel beam; the connecting end plate assembly of the steel beam is arranged on the side face of the steel pipe concrete column and comprises a connecting end plate, a one-way bolt connected with the fixing end plate and a shape memory alloy screw connected with the fixing end plate. The studs are arranged at the top of the steel beam and connected with the concrete slab. Compared with the prior art, it can be effectively guaranteed that the section of the steel beam and the section of the concrete-filled steel tubular column are always in an elastic state, and the beam-column joint has certain bearing capacity, rigidity and energy dissipation capacity and further has the advantages of self-repairing and self-resetting.

Description

Technical Field

[0001] This invention relates to the field of seismic resistance technology for building structures, specifically to a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy. Background Technology

[0002] With the continuous and rapid development of metal smelting technology, high-strength steel with strength grades of Q460 and above is gradually expanding its application in the field of building structures due to its excellent strength-to-weight ratio and price advantage per unit strength, especially showing significant advantages in lightweighting, green building and intelligent construction.

[0003] When high-strength steel-concrete composite structures are used in building structures, the design of beam-column connections faces new challenges. If rigid connections are used in traditional steel frame structures, the column sections connected to the beam ends will bear large bending moments under horizontal seismic loads, causing the column sections to prematurely yield and undergo significant plastic deformation, leading to structural failure. Furthermore, the plastic deformation also makes post-earthquake maintenance extremely difficult.

[0004] High-strength steel, due to its high strength-to-weight ratio and relatively low price per unit strength, is widely used in various building structures. Its higher strength allows for smaller component cross-sections, resulting in less impact on building space and better architectural aesthetics. However, as strength increases, the ductility of high-strength steel decreases. Therefore, in engineering applications, it is undesirable for high-strength steel-concrete composite columns to enter the plastic phase. Yet, under seismic loading, the structure requires energy-dissipating components to absorb seismic energy. Currently, no beam-column connection method can adequately address this problem. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy. The beam-column connection falls between hinged and steel joints, possessing certain load-bearing capacity, stiffness, and energy dissipation capacity. Furthermore, due to the addition of shape memory alloy screws, it can self-reset after moderate or major earthquakes, enabling self-repair of the beam-column connection and allowing the building to quickly return to usability.

[0006] Based on the above objectives, this application provides the following technical solution: One of the technical solutions of this application provides a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy, including a steel tube concrete column, a steel beam, a concrete floor slab, and a connecting end plate assembly; the steel tube concrete column is a regular square prism. The steel beam has an I-shaped cross-section and is composed of an upper flange steel plate, a lower flange steel plate, and an I-shaped vertical plate. The steel beam is symmetrically arranged on the side of the steel-concrete composite column, and the I-shaped section is connected to the steel-concrete composite column through a connecting end plate assembly. The concrete floor slab is placed horizontally on the upper flange steel plate of the steel beam, and the concrete floor slab and the steel beam are fixedly connected.

[0007] Furthermore, the connecting end plate assembly includes: a connecting end plate, a one-way bolt, and a shape memory alloy screw; the connecting end plate is welded to the steel beam; the one-way bolt and the shape memory alloy screw both pass through the connecting end plate and are embedded in the steel-concrete composite column.

[0008] Furthermore, the connecting end plate is disposed between the steel-concrete composite column and the steel beam, and the upper and lower flange steel plates of the steel beam are respectively welded to the connecting end plate at both ends; a plurality of one-way bolts are disposed on the left and right sides of the I-beam vertical plate of the steel beam; a plurality of shape memory alloy screws pass through the steel-concrete composite column to connect the steel beams on both sides.

[0009] Furthermore, the self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy also includes studs, which are welded to the steel beam and embedded in the concrete floor slab. The studs are used to improve the shear capacity between the concrete floor slab and the steel beam, enhancing their ability to work together.

[0010] Furthermore, the steel-concrete composite column uses steel pipes with a strength grade of Q460 or higher. The steel-concrete composite column has a closed section, and its interior is filled with self-compacting concrete; the steel-concrete composite column can reduce the impact of the bending moment at the ends of the steel beam on itself.

[0011] Furthermore, the concrete floor slab itself has high compressive bearing capacity, which is used to improve the flexural bearing capacity of the steel beam.

[0012] Furthermore, when the steel beam rotates relative to the steel-concrete composite column to a certain angle, the one-way bolt and the shape memory alloy screw will deform to dissipate energy.

[0013] The principle of this invention is as follows: A self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy is provided. The steel beam segment is connected to the steel tube concrete column through a connecting end plate using unidirectional bolts and shape memory alloy screws. A concrete floor slab is provided on the top of the steel beam, and studs are provided on the top of the steel beam. The studs are connected to the steel beam by welding.

[0014] The steel beams transfer the load to the connecting end plates, which then transmit it to the concrete-filled steel tube columns via one-way bolts and shape memory alloy screws on the end plates. Shear force is primarily transferred by the one-way bolts, while some bending moment is transferred to the concrete-filled steel tube columns through the tension and compression forces of the shape memory alloy screws.

[0015] Under minor earthquakes, all components and connections of this invention remain in an elastic state. Under moderate or major earthquakes, only the one-way bolts and shape memory alloy screws in the beam-column joints of this invention enter a plastic state to dissipate energy, while the rest remain in an elastic state. After a moderate or major earthquake, due to the high recovery strain rate and self-resetting characteristics of the shape memory alloy screws, the beam-column connections can self-repair, enabling the building to be quickly restored to use.

[0016] One of the technical solutions of this application provides an installation method for a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy, comprising the following steps: S1. Construct steel-concrete composite columns, and simultaneously complete the openings at the one-way bolts and the shape memory alloy screws; S2. Fabricate a steel beam and weld the studs to the upper flange steel plate of the steel beam; S3. Fabricate the connecting end plate and weld the upper and lower flange steel plates of the steel beam to the connecting end plate respectively; S4. Install the steel pipe portion of the steel-concrete composite column. After the steel pipe portion of the steel-concrete composite column is installed in place, use one-way bolts and shape memory alloy screws to connect the steel beam to the steel-concrete composite column through the connecting end plate. S5. After all components are installed, pour the concrete portion inside the steel pipe concrete column and pour the concrete floor slab.

[0017] Compared with the prior art, the present invention has the following advantages: (1) This invention has semi-rigid connection characteristics, possessing certain load-bearing capacity, stiffness, and energy dissipation capacity, while also exhibiting self-resetting and self-repairing features. Under minor earthquakes, all components and connections remain in an elastic state; under moderate or major earthquakes, only the unidirectional bolts and shape memory alloy screws enter plastic energy dissipation, while the rest remain elastic. After an earthquake, relying on the high recovery strain rate and self-resetting characteristics of the shape memory alloy screws, self-repair of beam-column connections can be achieved, facilitating the rapid recovery of buildings for use, effectively solving the application problems of high-strength steel components, and enabling the structural system to possess good seismic toughness, making it worthy of promotion.

[0018] (2) The steel-concrete composite column of the present invention uses high-strength closed-section steel pipes with a strength grade of Q460 or above, and is filled with self-compacting concrete to enhance its bearing capacity. The steel beam segment is connected to the steel-concrete composite column by means of a connecting end plate through one-way bolts and shape memory alloy screws. This node design can reduce the influence of the bending moment of the steel beam segment on the steel-concrete composite column and give full play to the bearing capacity of high-strength steel. In addition, the steel beam is welded to the concrete slab with studs. The studs can improve the shear bearing capacity between the concrete slab and the steel beam, enhance the synergistic effect between the two, and at the same time, take advantage of the high compressive bearing capacity of concrete to further enhance the bending bearing capacity of the steel beam.

[0019] (3) The one-way bolts and shape memory alloy screws on the connecting end plate of the present invention will deform and dissipate energy when the beam-column node rotates to a certain angle; and the shape memory alloy screws have a high strain recovery rate, which can realize the node self-reset after the earthquake, ensuring that the node can effectively dissipate energy and quickly recover to its initial state under the action of earthquake. Attached Figure Description

[0020] Figure 1 This is a perspective view of the self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy in the embodiment. Figure 2 This is a schematic plan view of the self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy in the embodiment. Figure 3 This is a side elevation view of the self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy in the embodiment. Figure 4 This is a schematic diagram of the end plate connection in the embodiment; Figure 5 This is a three-dimensional schematic diagram of the connecting end plate in the embodiment; Figure 6 This is a three-dimensional schematic diagram of the one-way bolt in the embodiment; Figure 7 This is a three-dimensional schematic diagram of the shape memory total screw in the embodiment; The numbers in the diagram indicate: 1. Concrete-filled steel tube column; 2. Steel beam; 3. Concrete floor slab; 4. Connecting end plate; 5. One-way bolt; 6. Shape memory alloy threaded rod; 7. Stud. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be described in detail below with reference to specific embodiments. It should be noted that the following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0022] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of the invention, it should be noted that unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] Example 1: A self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy like Figure 1-7 As shown, this embodiment provides a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy, the specific structure of which is as follows: 1. steel tube concrete column, 2. steel beam, 3. concrete floor slab, 4. connecting end plate, 5. one-way bolt, 6. shape memory alloy screw, 7. stud.

[0024] The steel-concrete composite column 1 is a regular square prism, made of high-strength steel tubing of Q460 or higher strength grade, and has a closed section. Self-compacting concrete is poured inside the steel tubing, fully combining the performance advantages of high-strength steel and concrete, significantly improving the load-bearing capacity of the steel-concrete composite column, while effectively reducing the impact of the bending moment at the ends of the steel beam 2 on the steel-concrete composite column.

[0025] Steel beam 2 has an I-shaped cross-section and is symmetrically arranged on the side of the steel-concrete composite column 1. The I-shaped section is connected to the steel-concrete composite column 1. The upper and lower flange steel plates of steel beam 2 are welded to the connecting end plate 4 at both ends.

[0026] The concrete floor slab 3 is placed horizontally on the upper flange of the steel beam 2 (i.e., the upper horizontal part of the I-beam). By utilizing the high compressive bearing capacity of concrete, the flexural bearing capacity of the steel beam 2 can be improved.

[0027] The connecting end plate assembly includes a connecting end plate 4, one-way bolts 5, and shape memory alloy screws 6. The connecting end plate 4 is positioned between the steel-concrete composite column 1 and the steel beam 2, and is welded to the steel beam 2. Several one-way bolts 5 are located on the left and right sides of the I-beam vertical plate of the steel beam 2. Two shape memory alloy screws 6 pass through the steel-concrete composite column 1, connecting the two sides of the steel beam 2 and ensuring that the two sides of the steel beam 2 are coaxial. Both the one-way bolts 5 and the shape memory alloy screws 6 pass through the connecting end plate 4 for fixing the steel beam 2.

[0028] The stud 7 is welded to the steel beam 2 and is installed between the steel beam 2 and the concrete floor slab 3, embedded in the concrete floor slab 3. The stud 7 can improve the shear bearing capacity between the concrete floor slab 3 and the steel beam 2, and enhance their ability to work together.

[0029] In some embodiments of the present invention, when the steel beam rotates relative to the steel-concrete composite column to a certain angle, the one-way bolts and shape memory alloy screws will deform, thereby achieving energy dissipation.

[0030] Example 2: Installation method of a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy like Figure 4 As shown, steel beam 2 is connected to steel-concrete composite column 1 via connecting end plate 4 using one-way bolts 5 and shape memory alloy screws 6. Steel beam 2 is connected to concrete slab 3 via studs 7.

[0031] like Figure 2 , Figure 3 , Figure 4 The installation sequence of each component of the beam-column joint is as follows: S1. The steel-concrete composite column 1 is fabricated in the factory using high-strength steel, and the holes for the one-way bolt 5 and the shape memory alloy screw 6 are also completed. S2. The steel beam 2 is fabricated in the factory, and the studs 7 are welded to the upper flange of the steel beam 2; S3. The connecting end plate 4 is manufactured in the factory, and the steel plates of the upper and lower flanges of the steel beam 2 are welded to the connecting end plate 4 respectively. S4. After transporting each component to the site, once the steel-concrete composite column 1 is installed in place, the steel beam 2 is connected to the steel-concrete composite column 1 using one-way bolts 5 and shape memory alloy screws 6 through the connecting end plate 4.

[0032] S5. After all components are installed, pour concrete into the steel pipe concrete column 1 and pour concrete floor slab 3.

[0033] The beam-column joint provided in the above embodiment possesses certain load-bearing capacity, stiffness, energy dissipation capacity, and self-resetting capability, making it a self-resetting semi-rigid beam-column connection. Under minor earthquakes, all components and connections in this embodiment remain in an elastic state. Under moderate or major earthquakes, only the one-way bolts and shape memory alloy screws in the beam-column joint of this embodiment enter a plastic state to dissipate energy, while the rest remain in an elastic state. After a moderate or major earthquake, due to the high recovery strain rate and self-resetting characteristics of the shape memory alloy screws, the beam-column connection achieves self-repair, enabling the building to quickly return to usability.

[0034] The design method of this invention is simple and applicable, easy to install on site, and has good economic and environmental benefits.

[0035] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy, characterized in that, It includes steel-concrete composite columns (1), steel beams (2), concrete floor slabs (3), and connecting end plate assemblies; The steel-concrete composite column (1) is a regular square prism; The steel beam (2) has an I-shaped cross section and is composed of an upper flange steel plate, a lower flange steel plate and an I-shaped vertical plate. The steel beam (2) is symmetrically arranged on the side of the steel tube concrete column (1), and the I-shaped cross section is connected to the steel tube concrete column (1) through a connecting end plate assembly. The concrete floor slab (3) is placed horizontally on the upper flange steel plate of the steel beam (2), and the concrete floor slab (3) and the steel beam (2) are fixedly connected.

2. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 1, characterized in that, The connecting end plate assembly includes: a connecting end plate (4), a one-way bolt (5), and a shape memory alloy screw (6); the connecting end plate (4) is welded to the steel beam (2); the one-way bolt (5) and the shape memory alloy screw (6) both pass through the connecting end plate (4) and are embedded in the steel tube concrete column (1).

3. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 2, characterized in that, The connecting end plate (4) is set between the steel pipe concrete column (1) and the steel beam (2). The upper flange steel plate and the lower flange steel plate of the steel beam (2) are welded to the connecting end plate (4) at both ends. Several one-way bolts (5) are set on the left and right sides of the I-beam vertical plate of the steel beam (2). Several shape memory alloy screws (6) pass through the steel pipe concrete column (1) to connect the steel beams (2) on both sides.

4. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 1, characterized in that, The self-resetting semi-rigid energy-dissipating composite beam-column node also includes a stud (7), which is welded to the steel beam (2) and embedded in the concrete floor slab (3).

5. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 4, characterized in that, The studs (7) are used to improve the shear bearing capacity between the concrete floor slab (3) and the steel beam (2) and enhance their ability to work together.

6. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 1, characterized in that, The steel-concrete composite column (1) uses steel pipes with a strength grade of Q460 or above.

7. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 6, characterized in that, The steel-concrete composite column (1) has a closed section and is filled with self-compacting concrete. The steel-concrete composite column (1) can reduce the influence of the bending moment at the end of the steel beam (2) on itself.

8. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to claim 1, characterized in that, The concrete floor slab (3) has high compressive bearing capacity, which is used to improve the bending bearing capacity of the steel beam (2).

9. The self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy according to any one of claims 1-8, characterized in that, When the steel beam (2) rotates to a certain angle relative to the steel-concrete composite column (1), the one-way bolt (5) and the shape memory alloy screw (6) will deform to dissipate energy.

10. An installation method for a self-resetting semi-rigid energy-dissipating composite beam-column joint with shape memory alloy as described in any one of claims 1-9, characterized in that, Includes the following steps: S1. Construct a steel-concrete composite column (1) and simultaneously complete the opening at the one-way bolt (5) and shape memory alloy screw (6); S2. Fabricate steel beam (2) and weld studs (7) to the upper flange steel plate of steel beam (2); S3. Make the connecting end plate (4) and weld the upper and lower flange steel plates of the steel beam (2) onto the connecting end plate (4) respectively. S4. Install the steel pipe part of the steel pipe concrete column (1). After the steel pipe part of the steel pipe concrete column (1) is installed in place, use one-way bolts (5) and shape memory alloy screws (6) to connect the steel beam (2) to the steel pipe concrete column (1) through the connecting end plate (4). S5. After all components are installed, pour the concrete inside the steel pipe concrete column (1) and pour the concrete floor slab (3).

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