CN103953123A - H-shaped steel frame node with partially restricted beam end and construction method thereof - Google Patents

Abstract

H-shaped steel frame joints partially restrained at beam ends and its construction method. The joints include fixed H-shaped steel beams and columns. The outer surface of the beam section of the H-shaped steel beam near the beam end is wrapped with an outer cladding layer, which is connected with the H-shaped steel beam. Two independent cavities are surrounded, and concrete is poured in the two cavities. The outer cladding layer and concrete work together to slow down or inhibit the local buckling of the H-shaped steel beam, and improve the deformation capacity and ductility of the structure; when the load is applied, the concrete participates in the work, so that the neutral axis of the H-shaped steel beam moves upward, More parts of the H-shaped steel beam section participate in tension, thereby improving the bending capacity and forcing the plastic hinge to move outward. Construction method: weld the end plate, studs and H-shaped steel beams in the factory, and weld the transverse stiffeners on the H-shaped steel columns; wrap the outer wrapping layer around the preset beam section at the end of the H-shaped steel beam; wrap the outer wrapping layer with Concrete is poured in the two cavities surrounded by H-shaped steel beams; the H-shaped steel beams and columns are connected at the construction site. The construction method greatly saves on-site construction time and facilitates construction.

Description

Partially Constrained H-shaped Steel Frame Joints at Beam Ends and Its Construction Method

technical field

The invention belongs to the technical field of building structures, and in particular relates to an H-shaped steel beam frame node partially restrained at beam ends and a construction method thereof.

Background technique

H-shaped steel frame is a kind of steel structure that is widely used at present. It is usually composed of H-shaped steel beams and H-shaped steel columns. H-shaped steel beams and H-shaped steel columns are connected by welding or bolts. In order to improve the ductility of this kind of frame and meet the requirements of seismic design, it is usually expected to form a plastic hinge at the end of the H-shaped steel beam and ensure a certain rotation capacity. In order to ensure that the steel frame achieves the design goals of "strong columns and weak beams" and "strong joints and weak members", and to dissipate the input of ground motion through the plastic hinges formed at the beam ends, structural measures are usually taken to force the plastic hinges at the beam ends to shift. At present, there are two main methods to move the plastic hinge position away from the column surface: 1. Locally strengthen the beam end, such as setting a haunch plate, a cover plate, etc. at the beam end of the H-shaped steel beam; 2. A certain distance from the column surface Local weakening of the beam section, such as local flange weakening or web opening, etc. However, these measures often lead to complex structure of the joint area, increase in the number of welds, and the need for on-site welding, which has the disadvantages of difficult construction and difficult to guarantee the quality of welds. In addition, due to the increased brittleness of steel in the heat-affected zone, brittle fracture of the flange of the steel beam is often caused, thereby reducing the deformation capacity of the H-shaped steel frame.

Contents of the invention

In order to solve the technical problems existing in the known technology, the present invention provides an H-shaped steel frame joint and a construction method with beam ends partially restrained. The joint has high ductility and reliable stress on the basis of meeting the requirements of bearing capacity. The method has the characteristics of saving on-site construction time and convenient construction.

The technical scheme that the present invention takes for solving the technical problem existing in known technology is:

H-shaped steel frame joints partially restrained at beam ends, including H-shaped steel beams and H-shaped steel columns welded with end plates, the end plates at the ends of H-shaped steel beams are fixedly connected with H-shaped steel columns through A plurality of transverse stiffeners are welded on the column at the core area of the node, which is characterized in that an outer cladding layer is wound on the outer surface of the beam section of the H-shaped steel beam near the beam end, and the outer cladding layer is surrounded by the H-shaped steel beam. There are two independent cavities closed around the periphery, and concrete is poured in the two cavities.

The present invention can also adopt following technical scheme:

The length of the beam segment wrapped with the outer cladding layer is 0.5-1 times the height of the H-shaped steel beam.

A plurality of studs are arranged on the inner side surfaces of the upper flange and the lower flange of the beam section wrapped with the outer wrapping layer, and the plurality of studs are all embedded in the concrete.

The outer wrapping layer is a carbon fiber cloth outer wrapping layer or an aramid fiber cloth outer wrapping layer.

The technical scheme that the present invention takes for solving the technical problem existing in known technology is:

The construction method of the H-shaped steel frame joint partially constrained by the beam end is characterized in that it comprises the following construction steps:

1) Weld the end plate, studs and H-shaped steel beams in the factory, and the studs are welded to the inner sides of the upper and lower flanges of the H-shaped steel beam ends, and the bolt holes are reserved on the end plates according to the design requirements. At the same time, transverse stiffeners are welded on the H-shaped steel column;

2) Apply colloid on the outer surface of the upper and lower flanges of the preset beam section at the end of the H-shaped steel beam, and then wrap carbon fiber cloth or aramid fiber cloth on the preset beam section. Apply matching colloid on the surface of carbon fiber cloth or aramid fiber cloth. After winding, an outer wrapping layer is formed. The outer wrapping layer and H-shaped steel beams form two independent cavities closed around the periphery;

3) After the colloid is solidified, pour concrete into the two cavities surrounded by the outer cladding layer and the H-shaped steel beam;

4) When the concrete strength meets the design requirements, the H-shaped steel beams and H-shaped steel columns are transported to the construction site, and the H-shaped steel beams and H-shaped steel columns are connected into a whole with threaded connectors on the construction site to form a partially restrained beam end. H-shaped steel frame nodes.

The advantages and positive effects that the present invention has are:

1. The outer cladding layer wound on the beam end beam section of the H-shaped steel beam and the concrete poured in the cavity work together to slow down or inhibit the local buckling of the H-shaped steel beam, and improve the bearing capacity on the basis of meeting the requirements of the bearing capacity. The deformation capacity and ductility of the structure are improved.

2. When bearing the load, the concrete poured in the cavity participates in the work, so that the neutral axis of the H-shaped steel beam moves upward, and more parts of the H-shaped steel section participate in tension, thereby improving the flexural bearing capacity. The plastic hinge is forced to move outward, which minimizes the number of beam end welds compared to the prior art.

3. Winding the outer wrapping layer and pouring concrete into the cavity are all completed in the factory. It is only necessary to connect and fix the H-shaped steel beams and H-shaped steel columns through threaded connectors at the construction site. Therefore, the site is greatly saved. Construction time and convenience for construction.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is an A-A sectional view of Fig. 1 .

In the figure: 1. H-shaped steel beam; 2. H-shaped steel column; 3. End plate; 4. Transverse stiffener; 5. Outer cladding; 6. Concrete; 7. Stud.

Detailed ways

In order to further understand the invention content, characteristics and effects of the present invention, the following examples are given, and detailed descriptions are as follows in conjunction with the accompanying drawings:

H-shaped steel frame joints partially restrained at the beam end, please refer to Figure 1-2, including H-shaped steel beam 1 and H-shaped steel column 2, and an end plate 3 is welded at the end of the H-shaped steel beam. The end plate at the end of the H-shaped steel beam is fixedly connected to the H-shaped steel column through high-strength bolts and matching nuts or other threaded connectors. A plurality of transverse stiffeners 4 are welded on the H-shaped steel column at the node core area. An outer cladding layer 5 is wound on the outer surface of the beam section near the beam end of the H-shaped steel beam. The outer cladding layer and the H-shaped steel beam enclose two independent cavities closed around the periphery, and concrete 6 is poured in the two cavities. Concrete is preferably concrete with micro-expansion effect, so that the cavity surrounded by the outer cladding layer and the H-shaped steel beam can be fully filled.

In the above structure, the length of the beam segment wrapped with the outer cladding layer is preferably 0.5-1 times the height of the H-shaped steel beam. This length value fully meets the requirement that the length of the plastic hinge formed at the beam end is usually 0.5-1 times the beam height.

In the above structure, a plurality of studs 7 are further welded on the inner sides of the upper flange and the lower flange of the beam section wrapped with the outer wrapping layer of carbon fiber cloth, and the plurality of studs are all embedded in the concrete. The stud structure can improve the cooperation between the concrete and the flange of the H-shaped steel beam, so that the concrete can better participate in the compression to change the position of the neutral axis.

In the above structure, the outer wrapping layer is preferably a carbon fiber cloth outer wrapping layer or an aramid fiber cloth outer wrapping layer.

The construction process of H-shaped steel frame joints partially constrained by beam ends is as follows:

1) Weld the end plate, studs and H-shaped steel beams in the factory, and the studs are welded to the inner sides of the upper and lower flanges of the H-shaped steel beam ends, and the bolt holes are reserved on the end plates according to the design requirements. At the same time, transverse stiffeners are welded on the H-shaped steel columns, and the layout requirements of the stiffeners and end plates are the same as those of ordinary H-shaped steel frame joints;

2) Apply colloid on the outer surface of the upper and lower flanges of the preset beam section at the end of the H-shaped steel beam, and then wrap carbon fiber cloth or aramid fiber cloth on the preset beam section. Apply matching colloid on the surface of carbon fiber cloth or aramid fiber cloth. After winding, an outer wrapping layer is formed. The outer wrapping layer and H-shaped steel beams form two independent cavities closed around the periphery;

3) After the colloid is solidified, pour concrete into the two cavities surrounded by the outer cladding layer and the H-shaped steel beam;

4) When the concrete strength meets the design requirements, transport the H-shaped steel beams and H-shaped steel columns to the construction site, and connect the H-shaped steel beams and H-shaped steel columns with high-strength bolts and matching nuts or other threaded connectors at the construction site Integral, H-shaped steel frame joints that form partly constrained beam ends.

The H-shaped steel frame joints partially constrained by beam ends have the advantages of simple structure and convenient construction. It is not only suitable for newly-built ordinary industrial and civil building structures, but also can be used for structural reinforcement of such steel frames, and has broad application prospects.

Claims (5)

1. H-shaped steel frame joints partially restrained at beam ends, including H-shaped steel beams and H-shaped steel columns welded with end plates at the ends, and the end plates at the ends of H-shaped steel beams are fixedly connected with H-shaped steel columns through threaded connectors. A plurality of transverse stiffeners are welded on the H-shaped steel column at the core area of the node, which is characterized in that: an outer wrapping layer is wound on the outer surface of the beam section of the H-shaped steel beam near the beam end, and the outer wrapping layer and the H-shaped steel beam It forms two independent cavities with closed perimeters, and concrete is poured in the two cavities. 2. The H-shaped steel frame node partially constrained by beam ends according to claim 1, characterized in that: the length of the beam segment wrapped with the outer wrapping layer is 0.5-1 times the height of the H-shaped steel beam. 3. The H-shaped steel frame joint constrained by beam ends according to claim 1, wherein a plurality of studs are arranged on the inner sides of the upper flange and the lower flange of the beam section wrapped with an outer cladding layer , a plurality of studs are embedded in the concrete. 4. The H-shaped steel frame node with beam ends partially constrained according to claim 1, characterized in that: the outer wrapping layer is a carbon fiber cloth outer wrapping layer or an aramid fiber cloth outer wrapping layer. 5. The construction method of the H-shaped steel frame joint of beam end partial restraint, it is characterized in that, comprises following construction steps: 1) Weld the end plate, studs and H-shaped steel beams in the factory, and the studs are welded to the inner sides of the upper and lower flanges of the H-shaped steel beam ends, and the bolt holes are reserved on the end plates according to the design requirements. At the same time, transverse stiffeners are welded on the H-shaped steel column; 2) Apply colloid on the outer surface of the upper and lower flanges of the preset beam section at the end of the H-shaped steel beam, and then wrap carbon fiber cloth or aramid fiber cloth on the preset beam section. Apply matching colloid on the surface of carbon fiber cloth or aramid fiber cloth. After winding, an outer wrapping layer is formed. The outer wrapping layer and H-shaped steel beams form two independent cavities closed around the periphery; 3) After the colloid is solidified, pour concrete into the two cavities surrounded by the outer cladding layer and the H-shaped steel beam; 4) When the concrete strength meets the design requirements, the H-shaped steel beams and H-shaped steel columns are transported to the construction site, and the H-shaped steel beams and H-shaped steel columns are connected as a whole with threaded connectors on the construction site to form a partially restrained beam end. H-shaped steel frame nodes.