Method for improving progressive collapse resistance bearing capacity of weak boundary constraint frame structure

Abstract

The invention relates to a method for improving progressive collapse resistance bearing capacity of a weak boundary constraint frame structure, which is characterized by comprising the following steps of: installing a buckling constraint support lower embedded part; pouring concrete of an embedded part floor at the lower part of the buckling restrained brace; installing an upper embedded part of the buckling restrained brace; concrete of an embedded part floor on the upper portion of the buckling restrained brace is poured, and a concrete frame structure is obtained; a gusset plate is installed on the concrete frame structure; and buckling restrained braces are installed between the gusset plates of the concrete frame, and the symmetrical buckling restrained brace frame structure is obtained. The method has the characteristics that the anti-seismic property of the frame structure is improved, and the anti-collapse bearing capacity of the weak boundary constraint frame structure can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete frame-buckling restraint support structure, in particular to a method for improving the anti-progressive collapse bearing capacity of a weak boundary restraint frame structure. Background Art

[0002] The anti-continuous collapse bearing capacity of the frame structure is mainly provided by the compression arch bearing capacity and catenary force bearing capacity of the beam. The compression arch bearing capacity is related to the bending bearing capacity of the beam, and the catenary bearing capacity is mainly related to the longitudinal reinforcement ratio, longitudinal reinforcement elongation and beam end rotation capacity. Therefore, the anti-continuous collapse bearing capacity of the frame structure can be directly increased by increasing the cross-sectional size and longitudinal reinforcement ratio, but when the surrounding structural members cannot provide sufficient constraints for the beam, the anti-collapse bearing capacity of the frame structure will drop sharply.

[0003] Problems with the existing technology: 1. When the structure is designed normally, the continuous collapse resistance of the frame structure is mainly affected by the cross-sectional height of the beam and its longitudinal reinforcement ratio. Improving the anti-collapse resistance of the structure by increasing the cross-sectional size of the beam and its longitudinal reinforcement ratio is not easy to meet the seismic requirements of strong columns and weak beams; if the cross-sectional size and longitudinal reinforcement ratio of the columns and beams are increased at the same time, the construction cost will also increase sharply. 2. In each span, the axial force borne by the corner column is small, and the other columns bear approximately the same axial force. However, when the second column and the penultimate column of each span fail, the lateral restraint provided by the structure is weak and the anti-collapse resistance is low.

[0004] Chinese patent 202311064207.0 discloses a fully assembled concrete frame buckling restrained support structure, which includes precast reinforced concrete beams, precast reinforced concrete columns, connecting sleeves, sleeve nodes, and buckling restrained supports. The precast reinforced concrete beams and precast reinforced concrete columns are provided with connecting sleeves at both ends, and bolts are arranged inside the connecting sleeves. The connecting nodes are sleeve nodes. The precast reinforced concrete beams and precast reinforced concrete columns are welded to the sleeve nodes through the connecting sleeves at both ends, and the buckling restrained supports are connected to the sleeve nodes through the node plates thereon. Although this structure can resist earthquakes, it is not effective in resisting collapse. Summary of the invention

[0005] The present invention provides a method for improving the anti-continuous collapse bearing capacity of a weak boundary constraint frame structure, which can not only improve the seismic performance of the structure, but also improve the anti-collapse bearing capacity of the structure.

[0006] A method for improving the anti-progressive collapse bearing capacity of a weak boundary restrained frame structure of the present invention comprises the following steps: Step 1: Install the lower embedded parts of the buckling restraint support; Step 2: pouring concrete of the lower embedded parts floor of the buckling restraint support; Step 3: Install the upper embedded parts of the buckling restraint support; Step 4: pouring concrete of the upper embedded parts floor of the buckling restraint support to obtain a concrete frame structure; Step 5: Install node plates on the concrete frame structure. Two node plates are installed in each concrete frame, one of which is installed at the inner corner of the bottom of the concrete frame structure of two adjacent spans, and the other node plate is installed at the outer corner of the top of the concrete frame structure of two adjacent spans; Step 6: Install buckling restrained braces between the node plates of the concrete frame to obtain a symmetrical buckling restrained braced frame structure.

[0007] The step 1 comprises: Step 11: Support the formwork and tie the beam and column reinforcement cage of the floor where the lower embedded parts are located; Step 12: Install the lower embedded parts in the steel cage of the floor beam where they are located. During the installation process, spot weld the embedded parts to the steel bars in the steel cage to fix the position of the embedded parts.

[0008] The step 3 comprises: Step 31: Support the formwork and install the upper embedded parts in the formwork of the floor; Step 32: Tie up the beam and column reinforcement cages of the floor where the upper embedded parts are located, spot weld the embedded parts and the steel bars in the reinforcement cages, and fix the positions of the embedded parts.

[0009] In step 5, when installing the node plate, the node plate and the embedded parts are welded in the form of a single-sided V-shaped weld, and then a stiffening rib is arranged between the node plate and the embedded parts, and the stiffening rib is connected to the node plate and the embedded parts by welding.

[0010] The buckling restrained brace frame structure comprises two concrete frame structures in each span, and buckling restrained braces are symmetrically arranged in each group of concrete frame structures.

[0011] In step 6, the buckling restraint support is connected to the node plate via a pin.

[0012] The existing buckling braces are mainly used to improve the seismic performance of the structure, and the arrangement methods are various. The arrangement of buckling braces to improve the progressive collapse resistance of the weak boundary restrained frame structure has not been considered. In the structure of the present invention, buckling restrained braces are symmetrically arranged in two adjacent spans of each frame. The buckling restrained braces act as tension rods to provide the structure with anti-collapse bearing capacity during the failure of the second column or the penultimate column of each frame. The method for improving the progressive collapse resistance of the weak boundary restrained frame structure proposed in the present invention not only improves the seismic performance of the frame structure, but also improves the anti-collapse bearing capacity of the weak boundary restrained frame structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a structural schematic diagram of the multi-span structure of the present invention; Figure 3 This is a structural diagram of the connection between the buckling restrained brace and the concrete frame of the present invention. Specific implementation methods

[0014] In order to make the purpose, technical solutions and advantages of the invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. Example

[0015] The present invention Figures 1 to 3 As shown, a method for improving the anti-progressive collapse bearing capacity of a weak boundary restrained frame structure comprises the following steps: Step 1: Install the lower embedded part 4 of the buckling restraint support; Step 2: pouring concrete of the 4th floor of the lower embedded parts of the buckling restraint support; Step 3: Install the upper embedded part 4 of the buckling restraint support; Step 4: pouring concrete of the upper embedded parts 4 of the buckling restraint support to obtain a concrete frame structure 1; Step 5: Install the node plate 2 on the concrete frame structure 1, and install two node plates 2 in each concrete frame, wherein one node plate 2 is installed at the inner corner of the bottom of the concrete frame structure 1 of two adjacent spans, and the other node plate 2 is installed at the outer corner of the top of the concrete frame structure 1 of two adjacent spans; Step 6: Install buckling restrained braces between the node plates 2 of the concrete frame to obtain a symmetrical buckling restrained braced frame structure.

[0016] Further, the step 1 comprises: Step 11: Support the formwork and tie the beam and column reinforcement cage of the floor where the lower embedded part 4 is located; Step 12: Install the lower embedded part 4 in the steel cage of the floor beam where it is located. During the installation process, spot weld the embedded part 4 to the steel bars in the steel cage to fix the position of the embedded part 4.

[0017] Specifically, the step 3 includes: Step 31: Support the formwork and install the upper embedded part 4 in the formwork of the floor; Step 32: Tie up the beam and column reinforcement cages of the floor where the upper embedded parts 4 are located, spot weld the embedded parts 4 with the reinforcements in the reinforcement cages, and fix the positions of the embedded parts 4.

[0018] Furthermore, in step 5, when installing the node plate 2, the node plate 2 and the embedded part 4 are welded in the form of a single-sided V-shaped weld, and then a stiffening rib 5 is arranged between the node plate 2 and the embedded part 4, and the stiffening rib 5 is connected to the node plate 2 and the embedded part 4 by welding.

[0019] Furthermore, in the buckling restrained brace frame structure, every two spans of concrete frame structures form a group, and buckling restrained braces are symmetrically arranged in each group of concrete frame structures.

[0020] In step 6, the buckling restraint support is connected to the node plate 2 via a pin. Example

[0021] A method for improving the progressive collapse resistance of a weak boundary restrained frame structure comprises the following steps: Step 1: Install the lower embedded part 4 of the buckling restraint support; Step 2: pouring concrete of the 4th floor of the lower embedded parts of the buckling restraint support; Step 3: Install the upper embedded part 4 of the buckling restraint support; Step 4: pouring concrete of the upper embedded parts 4 of the buckling restraint support to obtain a concrete frame structure 1; Step 5: Install the node plate 2 on the concrete frame structure 1, and install two node plates 2 in each concrete frame, wherein one node plate 2 is installed at the inner corner of the bottom of the concrete frame structure 1 of two adjacent spans, and the other node plate 2 is installed at the outer corner of the top of the concrete frame structure 1 of two adjacent spans; Step 6: Install buckling restrained braces between the node plates 2 of the concrete frame to obtain a symmetrical buckling restrained braced frame structure.

Claims

1. A method for improving the progressive collapse resistance of a weak boundary constraint frame structure, characterized in that: The following steps are included: Step 1: Install the lower embedded parts of the buckling restraint support; Step 2: pouring concrete of the lower embedded parts floor of the buckling restraint support; Step 3: Install the upper embedded parts of the buckling restraint support; Step 4: pouring concrete of the upper embedded parts floor of the buckling restraint support to obtain a concrete frame structure; Step 5: Install node plates on the concrete frame structure. Two node plates are installed in each concrete frame, one of which is installed at the inner corner of the bottom of the concrete frame structure of two adjacent spans, and the other node plate is installed at the outer corner of the top of the concrete frame structure of two adjacent spans; Step 6: Install buckling restrained braces between the node plates of the concrete frame to obtain a symmetrical buckling restrained braced frame structure.

2. The method for improving the progressive collapse resistance of a weak boundary restrained frame structure according to claim 1, characterized in that: The step 1 comprises: Step 11: Support the formwork and tie the beam and column reinforcement cage of the floor where the lower embedded parts are located; Step 12: Install the lower embedded parts in the steel cage of the floor beam where they are located. During the installation process, spot weld the embedded parts to the steel bars in the steel cage to fix the position of the embedded parts.

3. The method for improving the progressive collapse resistance of a weak boundary restrained frame structure according to claim 1, characterized in that: The step 3 comprises: Step 31: Support the formwork and install the upper embedded parts in the formwork of the floor; Step 32: Tie up the beam and column reinforcement cages of the floor where the upper embedded parts are located, spot weld the embedded parts and the steel bars in the reinforcement cages, and fix the positions of the embedded parts.

4. The method for improving the progressive collapse resistance of a weak boundary restrained frame structure according to claim 1, characterized in that: In step 5, when installing the node plate, the node plate and the embedded parts are welded in the form of a single-sided V-shaped weld, and then a stiffening rib is arranged between the node plate and the embedded parts, and the stiffening rib is connected to the node plate and the embedded parts by welding.

5. The method for improving the progressive collapse resistance of a weak boundary restrained frame structure according to claim 1, characterized in that: The buckling restrained brace frame structure comprises two concrete frame structures in each span, and buckling restrained braces are symmetrically arranged in each group of concrete frame structures.

6. The method for improving the progressive collapse resistance of a weak boundary restrained frame structure according to claim 1, characterized in that: In step 6, the buckling restraint support is connected to the node plate via a pin.

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