CN104863267A - A new type of beam-column reinforced joint with variable thickness of beam end flange - Google Patents

Abstract

The invention discloses a novel beam column reinforced node with variable thickness of a flange at the end part of a beam. The reinforced node is formed by welding and connecting a beam with a flange made of a longitudinal variable cross-section steel plate and a stud. According to the stress form, the node adopts the flange variable thickness of the inner beam in a certain area of the node, and the reasonable thickness variable gradient is selected through design calculation, so that the strength, the rigidity and the energy consumption capability of the node are ensured. During installation, the high-strength bolt is firstly used as a positioning bolt to connect the beam web plate to the shear plate of the column flange, the beam longitudinal variable-thickness flange is welded on the column flange through the full penetration single-sided groove, and after the beam flange and the column flange are welded, the high-strength bolt is screwed down to complete the whole installation process. The node, the flange and the reinforcing cover plate are integrated, so that the influence caused by local stress concentration and welding is avoided, the processing and mounting steps are simple, the material utilization rate is high, the construction cost is low, the strength and the rigidity of the node can be ensured, the energy consumption capability is high, and the node can be used for earthquake-proof defense areas.

Description

A new type of beam-column reinforced joint with variable thickness of beam end flange

technical field

The invention relates to the technical field of beam-column connection in steel structure buildings, more specifically, to a novel reinforced joint for beam-column rigid connection, in particular to a novel beam-column reinforced joint with variable thickness of beam end flanges.

technical background

Frame structure is a common structural system in steel structure buildings. In order to realize the design idea of "strong columns and weak beams, strong nodes and weak components" and avoid brittle failure of beam-column joints under strong earthquakes, the cover-plate-reinforced type is often used at present. node to improve the seismic performance of the node. However, there are some deficiencies in this cover-type reinforced joint connection. The length of the cover plate has little influence on the strength, stiffness, and ductility of the beam-to-column connection. The stress concentration of the joint is unfavorable to the force bearing of the beam-column connection; as the length increases, not only is the steel wasted, but also the welding of the cover plate and the flange leads to the increase of the heat-affected zone and the increase of welding defects, which makes the stress state of the joint complicated, and has a great impact on the joint. More adverse effects. Therefore, it is necessary to invent a new beam-column reinforced joint, which can eliminate the adverse effects caused by the length of the cover plate and welding, which can not only ensure the performance of the joint, but also ensure the simple processing, manufacturing and installation, and improve the utilization rate of materials.

Contents of the invention

The purpose of the present invention is to address the above disadvantages and provide a new type of beam-column reinforced joint with variable thickness of the flange at the end of the beam, which can eliminate the adverse effects caused by the length of the cover plate and welding. This node adopts the longitudinal variable section steel plate (LP steel plate) as the flange, and the thickness change slope is designed according to the stress at the node, and there is no need for secondary processing to weld the cover plate to strengthen the node. The flange and the reinforced cover are integrated to avoid local stress concentration and welding influence. The reinforced joint with variable thickness of the beam end flange provided by the present invention has simple processing and installation steps, high material utilization rate and low construction cost, can not only ensure the strength and rigidity of the joint, but also has strong energy dissipation capacity, and can be used in earthquake-resistant fortified areas .

The beam-column reinforced joint with variable thickness of the flange at the end of the beam is realized by adopting the following technical scheme:

The beam-column-reinforced joint with variable-thickness flange at the end of the beam is formed by bolt-welding the beam and column with longitudinally variable-section steel plate as the flange. The longitudinal variable-section flange of the beam is composed of longitudinal variable-section steel plates, and the thickness change slope is designed according to the stress at the node, without secondary processing to weld the cover plate to strengthen the node, and the flange and the reinforced cover plate are integrated to avoid local stress concentration and welding effects.

The present invention can form the reinforced node according to two methods according to the needs of designers. One is to form the reinforced node by adopting the method of changing the thickness of the beam flange in a certain area of the node and equal thickness of the beam flange in other areas according to the force of the node; the other is According to the force of the frame beam, the longitudinal variable section beam is designed by using the longitudinal variable section steel plate as the flange (also can be used as the web).

The longitudinal variable section steel plate changes the longitudinal thickness by continuously changing the opening degree of the roll during the rolling process, and can be customized into different shapes according to needs, including different thicknesses, different thickness change gradients, and different lengths of variable thickness sections. The mechanical properties of the steel plate meet the requirements of the relevant specifications, and the difference in mechanical properties at different thicknesses is small.

The beam-column reinforced joint described above uses high-strength bolts as positioning bolts to connect the beam web to the shear plate of the column flange during installation. For the column flange, after the beam flange and the column flange are welded, tighten the high-strength bolts to complete the entire installation process.

After adopting the beam-column reinforced joint with variable thickness of the flange at the end of the beam, the manufacturing and installation steps are greatly reduced, the installation cost is reduced, the material utilization rate is improved, and the steel requirement is reduced. In addition, by using variable thickness flanges to strengthen the joints, the bending resistance of the joints is higher than that of the joints, ensuring the strength and stiffness of the joints, and thus making the plastic hinges in the beams at the flanges of equal thickness form before the joints under earthquake action, ensuring The elastic working state of the beam-column joint improves the ductility of the joint and enhances the energy dissipation capacity of the joint. The installation and fixation of the beam-column reinforced joint with variable thickness of the flange at the end of the beam does not require welding cover plates on the flange of the beam, which not only reduces the cost but increases the convenience of installation, but also does not cause stress concentration, increase of welding heat-affected zone and welding The increase of defects affects the mechanical performance of the beam flange at the joint. The vertically variable thickness steel plate adopted in the node of the present invention changes the longitudinal thickness by continuously changing the opening degree of the roll during the rolling process. Anshan Iron and Steel Manufacturing Plant can already produce this type of steel plate. Although the processing cost will increase slightly, the comprehensive installation , transportation, eliminating the need to strengthen the cover to reduce various costs, and the use of this node form to improve the performance of the node, so that the overall benefit is greatly improved, and it provides favorable conditions for its wide-scale application and promotion.

Description of drawings

Figures 1A to 1C are schematic diagrams of different types of beam-column reinforced joints with variable thickness of beam end flanges, respectively describing Type I joints, Type II joints, and Type III joints.

2A and 2B are detailed diagrams illustrating the connection of beam-column-reinforced joints with variable thickness flanges at the ends of I-beams according to a specific embodiment of the present invention.

Fig. 3 is a schematic diagram of the shape of a longitudinally tapered steel plate used in a specific embodiment of the present invention.

Specific implementation method

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1A, 1B and 1C, the present invention proposes the following three types of beam-column reinforced joints with variable thickness of beam end flanges. Type I joint (Fig. 1A): the upper surface of the upper flange 3a is inclined and the lower surface is horizontal; the upper surface of the lower flange 3a' is horizontal and the lower surface is inclined; The surface is inclined, the upper surface of the lower flange 3b' is inclined, and the lower surface is horizontal; Type III node (Fig. 1C): the upper surface of the upper flange 3c is horizontal, the lower surface is inclined, and the upper surface of the lower flange 3c' is horizontal, and the lower surface is inclined. The height of the web plate of type I joints remains unchanged and no further processing is required, but the slope on the upper surface of the upper flange will cause inconvenience to the installation of profiled steel plates on the floor; the height of the web plates of type II and III joints with variable thickness changes and needs to be processed again. However, the surface of the upper flange is horizontal, which is convenient for the installation of the roof panel, and the designer can choose it independently according to the needs.

As shown in Figures 2A and 2B, in a specific implementation manner, the beam-column reinforced joint with variable thickness of the beam end flange used in the present invention includes an I-shaped cross-section column flange 1, a column web 2, an I-shaped Section beam longitudinal variable thickness flange 3, beam web 4, column plus tibia rib 5, welding backing plate 6, column flange shear plate 7. The column plus tibial rib 5 is welded to the column flange 1 and the web 2, the longitudinal variable thickness flange 3 of the beam is welded to the column flange 1 with full penetration single-sided groove, and the beam web 4 is bolted to the column wing with high-strength bolts Shear plate 7 on edge 1. The longitudinal variable thickness flange 3 of the I-shaped cross-section beam can be butt welded by variable thickness steel plate and equal thickness steel plate, as shown in Figure 3, including variable thickness section 31 and equal thickness section 32, and 33 in the figure represents the butt weld; The longitudinal variable cross-section beam is designed for the frame beam, and the whole longitudinal variable cross-section steel plate is customized as the flange (also can be used as the web), and the shape can be determined according to the specific force.

In the specific implementation process: the beam and column components are prefabricated in the prefabrication factory, and the node installation is completed on the construction site. During installation, the high-strength bolts are firstly used as positioning bolts to connect the beam web 4 to the shear plate 7 on the column flange 1. After the beam flange 3 and the column flange 1 are welded, the high-strength bolts are tightened to complete the entire installation process. The improved node strengthening method of the present invention adopts longitudinally variable section beam flanges instead of reinforced cover plates to be welded with beam flanges, simplifies processing and installation steps, saves materials, and ensures node performance.

In the above description, some preferred implementations have been specifically described, and some technical details are provided for the purpose of illustration, but those skilled in the art should be able to understand that the present invention can have various changes and more different Embodiments, and the details described herein can be quite changed without departing from the spirit and gist of the present invention, and thus should belong to the scope of protection claimed by the present application.

Claims (10)

1. A novel beam-column reinforced joint with variable thickness of the flange at the end of the beam, which comprises a structure in which the beam and the column are bolted and welded by the longitudinally variable section flange of the beam, wherein the longitudinally variable section flange of the beam is formed by the longitudinally variable section flange It is made of steel plate, and the slope of the thickness change is designed according to the stress at the joint. No need for secondary processing to weld the cover plate to strengthen the joint. The flange and the reinforced cover plate are integrated to avoid the influence of local stress concentration and welding. 2. The beam-column reinforced joint according to claim 1, further comprising: I-shaped section column flange, column web, I-shaped section beam longitudinal variable thickness flange, beam web, column plus tibia, Welding backing plate, column flange shear plate, wherein the column tibia rib is welded to the column flange and to the web, and the longitudinal variable thickness flange of the beam is welded with full penetration single-sided groove The column flange and the beam web are bolted to the shear plate on the column flange with high-strength bolts. 3. The beam-column-reinforced joint according to claim 1, wherein, in the structure of the longitudinal variable-section flange, the thickness of the beam flange in a certain area of the joint is variable, and the thickness of the beam flange in other areas is equal. 4. The beam-column-reinforced node according to claim 3, wherein the structure of the longitudinally variable-section flange is formed by butt welding of longitudinally variable-section steel plates and equal-thickness steel plates. 5. The beam-column-reinforced joint according to claim 1, wherein the structure of the longitudinal variable-section flange is to design a longitudinal variable-section beam according to the stress of the beam member, and customize a whole piece of longitudinal variable-section steel plate as the flange and The web, naturally forms the structure of the variable thickness of the flange at the end of the beam. 6. The beam-column-reinforced joint according to claim 1, wherein, the longitudinal variable-section steel plate changes the longitudinal thickness by continuously changing the opening degree of the roll during the rolling process, so as to be rolled into different thicknesses according to requirements, Different thickness change slopes, different lengths of variable thickness sections, and the mechanical properties of the steel plate are required to meet the requirements of relevant specifications, and the difference in mechanical properties at different thicknesses is small. 7. The beam-column reinforced joint according to claim 2, wherein the longitudinal variable thickness flange of the I-shaped cross-section beam includes an upper flange and a lower flange, the upper surface of the upper flange is inclined, and the lower surface is horizontal, The upper surface of the lower flange is horizontal and the lower surface is inclined. 8. The beam-column reinforced joint according to claim 2, wherein the longitudinal variable thickness flange of the I-shaped cross-section beam includes an upper flange and a lower flange, the upper surface of the upper flange is horizontal and the lower surface is inclined, The upper surface of the lower flange is inclined and the lower surface is horizontal. 9. The beam-column reinforced joint according to claim 2, wherein the longitudinal variable thickness flange of the I-shaped cross-section beam includes an upper flange and a lower flange, the upper surface of the upper flange is horizontal and the lower surface is inclined, The upper surface of the lower flange is horizontal and the lower surface is inclined. 10. The beam-column reinforced node according to claim 2, when installing, the beam web is connected to the shear plate of the column flange by using the high-strength bolts as positioning bolts, and the beam The full-penetration single-side groove of the longitudinal variable thickness flange is welded to the column flange, and after the beam flange and the column flange are welded, the high-strength bolts are tightened to complete the entire installation process.