CN218580847U - A Hybrid Buckling Constrained Brace - Google Patents

Abstract

The utility model discloses a hybrid buckling restrained brace, which is obliquely arranged along the diagonal direction of a frame main body and comprises a buckling support unit and a rigid support unit which are connected with each other by a coaxial line; the first end of the buckling support unit is connected with one end of the frame main body, the second end of the buckling support unit is connected with the first end of the rigid support unit, and the second end of the rigid support unit is connected with the other end of the frame main body; the buckling support unit is detachably and fixedly connected with the rigid support unit; the utility model effectively reduces the length of the yielding section in the buckling support unit, ensures that the axial strain of the buckling support unit can be fully exerted, and improves the anti-seismic performance of the buckling restrained brace frame structure; by arranging the rigid supporting unit, the supporting rigidity is greatly improved, so that the interlayer deformation of the structure is reduced, and the post-earthquake restoration capability of the frame structure is facilitated; simple structure, workable, the efficiency of construction is high.

Description

A Hybrid Buckling Constrained Brace

technical field

The utility model belongs to the technical field of building structures, in particular to a hybrid buckling constraint support.

Background technique

Buckling-restrained braces (BRB) frame structure is an effective anti-lateral force system in buildings in seismically active areas; compared with the existing ordinary steel braced frame structure, it has stable energy consumption, high bearing capacity and ductility Good and other advantages.

At present, through the research on the existing buckling-constrained braced frame structure, it is found that the main body of the frame is damaged before the buckling-constrained brace in the earthquake, and most of the damage occurs at the foot of the column; at the same time, due to the existing buckling-constrained The diagonal of the main body is arranged throughout the length, and the axial strain of the buckling-constrained brace is often limited to less than 2%; before the buckling-constrained braced frame structure fails, the excellent deformation capacity of the core elements in the buckling-constrained brace cannot be fully utilized; resulting in buckling The seismic performance of the restrained braced frame structure is low; in addition, after the buckling restrained brace yields, its axial stiffness decreases sharply, resulting in a significant decrease in the lateral stiffness of the buckling restrained braced frame structure, and large interstory deformation, which has a great impact on the buckling restrained braced frame structure. The post-earthquake repair is extremely unfavorable.

Utility model content

Aiming at the technical problems existing in the prior art, the utility model provides a hybrid buckling-constrained support to solve the problem that the deformation capacity of the buckling-constrained support in the existing buckling-constrained support frame structure cannot be fully exerted, and the interlayer deformation is relatively large, resulting in The seismic performance of the buckling-constrained braced frame structure is low, and the technical problems of post-earthquake repair are difficult.

In order to achieve the above object, the technical solution adopted by the utility model is:

The utility model provides a hybrid buckling restraint support, which is arranged obliquely along the diagonal direction of the frame main body; the hybrid buckling restraint support includes a buckling support unit and a rigid support unit connected with a coaxial line;

The first end of the buckling support unit is used to connect with one end of the frame body, the second end of the buckling support unit is connected to the first end of the rigid support unit, and the second end of the rigid support unit is used for It is connected with the other end of the frame main body; wherein, the buckling support unit and the rigid support unit are connected by a detachable fixed connection.

Further, the buckling support unit includes a core plate, a first outer restraint cover plate, a second outer restraint cover plate, a first backing plate, a second backing plate, a number of first high-strength bolts and a number of second high-strength bolts;

The chip includes a first non-yielding section, a yielding section, and a second non-yielding section arranged in sequence in the axial direction, and the first backing plate, the yielding section, and the second backing plate are located in the same plane; wherein, the The first backing plate is arranged on one side of the long axis direction of the yield section, and the second backing plate is arranged on the other side of the long axis direction of the yield section; the first outer restraint cover plate, the yield section segment and the second outer constraining cover plate are arranged in parallel in turn; wherein, the first outer constraining cover plate is located on one side of the plane where the yield section is located, and the second outer constraining cover plate is located on the plane where the yield section is located the other side of

One side of the first outer restraint cover, one side of the first backing plate and one side of the second outer restraint cover are fixedly connected together by a plurality of first high-strength bolts; the first outer restraint cover The other side of the plate, the second backing plate and the other side of the second outer restraint cover are fixedly connected together by several second high-strength bolts.

Further, one side of the first outer constraining cover plate is provided with several first bolt holes, and several first bolt holes are evenly arranged along the long axis direction of the first outer constraining cover plate; the first backing plate A number of second bolt holes are arranged, and the number of second bolt holes are evenly arranged along the long axis direction of the first backing plate; one side of the second outer restraint cover is provided with a number of third bolt holes, and a number of third bolt holes The holes are evenly arranged along the long axis direction of the second outer constraining cover plate;

Wherein, the first bolt hole, the second bolt hole and the third bolt hole are provided in one-to-one correspondence, and the first high-strength bolt passes through the first bolt hole, the second bolt hole and the third bolt hole in sequence. The third bolt hole is used to fix and connect one side of the first outer restraint cover, the first backing plate and one side of the second outer restraint cover.

Further, the other side of the first outer restraint cover is provided with several fourth bolt holes, and the fourth bolt holes are evenly arranged along the long axis direction of the first outer restraint cover; the second backing plate A number of fifth bolt holes are arranged on the top, and the number of fifth bolt holes are evenly arranged along the long axis direction of the second backing plate; the other side of the second outer restraint cover is provided with a number of sixth bolt holes, and a number of sixth bolt holes are arranged on the other side of the second backing plate. Six bolt holes are evenly arranged along the long axis direction of the second outer restraint cover plate;

Wherein, the fourth bolt hole, the fifth bolt hole and the sixth bolt hole are provided in one-to-one correspondence, and the second high-strength bolt passes through the fourth bolt hole, the fifth bolt hole and the sixth bolt hole in sequence. The sixth bolt hole is used to fix and connect the other side of the first outer constraining cover plate, the first backing plate and the other side of the second outer constraining cover plate together.

Further, the buckling support unit also includes a first stiffener and a second stiffener;

The first stiffeners are arranged symmetrically on the central axis of both sides of the first non-yielding section, and the first stiffeners are vertically fixed to the first non-yielding section; the second stiffeners are arranged symmetrically on the first non-yielding section On the central axis of both sides of the second non-yielding section, the second stiffener is vertically fixed to the second non-yielding section.

Further, the length of the yield section is 30%-50% of the diagonal length of the frame main body.

Further, it also includes a first connection end plate and a second connection end plate arranged in parallel;

The first connecting end plate is vertically fixed on the second end of the buckling support unit, and the second connecting end plate is vertically fixed on the first end of the rigid supporting unit; the first connecting end plate is connected to the The second connecting end plates are fixedly connected together by third high-strength bolts.

Further, the rigid support unit includes a square steel pipe and an end welded plate; one end of the square steel pipe is connected to the second end of the buckling support unit, and the other end of the square steel pipe is connected to the end welded plate One side is fixedly connected, and the other side of the end welding plate is used to be connected with the other end of the frame main body.

Compared with the prior art, the beneficial effects of the utility model are:

The utility model provides a hybrid buckling-constrained support. By connecting the buckling support unit and the rigid support unit in series, the length of the yield section in the buckling support unit is effectively reduced, and the axial strain energy of the buckling support unit can be fully exerted. , which improves the seismic performance of the buckling-constrained bracing frame structure; by setting the rigid bracing unit, the backup stiffness is provided for the bracing, and the bracing stiffness is greatly improved to reduce the interstory deformation of the structure; at the same time, the buckling bracing unit and the rigid bracing unit The use of detachable fixing is convenient for the post-earthquake repair ability of the frame structure; the structure is simple, easy to process, and can give full play to the plastic deformation ability of the material, and the construction efficiency is high.

Furthermore, by arranging backing plates on both sides of the core plate and fixing the backing plates together with the outer restraint cover, the stiffness of the buckling support unit is effectively improved, and the buckling section can fully exert its plastic deformation ability.

Furthermore, by setting stiffeners in the non-yielding section, the stiffness and strength of the non-yielding section are effectively improved, and the deformation process of the buckling support unit is avoided. The non-elastic deformation does not occur in the non-yielding section, which improves the stability and reliability of the connection area. sex.

Furthermore, the length of the buckling section can be flexibly set according to the shock absorption requirements of the structure, which ensures that the buckling section can give full play to the superior plastic deformation and energy dissipation capacity of steel in the frame structure, thereby reducing the impact on the main structure during earthquakes. damage.

Furthermore, square steel pipes are set in the rigid support unit to provide backup stiffness for the support, and the buckling-constrained support part that reduces the length of the yield section helps the components to be replaced after the earthquake.

Description of drawings

Fig. 1 is the schematic diagram of the three-dimensional structure of the hybrid buckling-constrained support described in the utility model;

Figure 2 is an exploded view of the hybrid buckling restraint support described in the present invention;

Fig. 3 is the front view of the hybrid buckling restraint support described in the utility model;

Fig. 4 is a top view of the hybrid buckling-constrained brace described in the present invention;

Fig. 5 is a left view of the hybrid buckling-constrained support described in the utility model;

Fig. 6 is a right view of the hybrid buckling-constrained support described in the utility model;

Fig. 7 is a schematic diagram of the connection structure between the hybrid buckling-constrained support and the frame main body described in the present invention.

Among them, 1 core plate, 2 first outer restraint cover plate, 3 second outer restraint cover plate, 4 first backing plate, 5 second backing plate, 6 first high-strength bolt, 7 second high-strength bolt, 8 first stiffening Ribs, 9 second stiffeners, 10 square steel pipes, 11 end welded plates, 12 first connecting end plates, 13 second connecting end plates, 14 third high-strength bolts, 15 frame main body.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects solved by the utility model clearer, the following specific examples will further describe the utility model in detail. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

As shown in the accompanying drawings 1-7, the utility model provides a hybrid buckling restraint support, which is arranged in the frame main body 15 and arranged obliquely along the diagonal direction of the frame main body 15; The combination of the hybrid buckling restraint support and the frame main body 15 forms a buckling restraint support frame structure; the hybrid buckling restraint support includes a buckling support unit and a rigid support unit connected by a coaxial line; the first end of the buckling support unit For connecting with one end of the frame body 15, the second end of the buckling support unit is connected with the first end of the rigid support unit, and the second end of the rigid support unit is used for connecting with the other end of the frame body 15 .

In the utility model, a detachable fixed connection is adopted between the buckling support unit and the rigid support unit; a first connecting end plate 12 and a second connecting end plate 12 are also arranged between the buckling supporting unit and the rigid supporting unit. End plate 13, the first connection end plate 12 and the second connection end plate 13 are arranged in parallel; the first connection end plate 12 is vertically fixed on the second end of the buckling support unit, and the second connection The end plate 13 is vertically fixed on the first end of the rigid support unit.

The first connection end plate 12 and the second connection end plate 13 are fixedly connected together by third high-strength bolts 14; wherein, the first connection end plate 12 is evenly provided with first threaded holes around the periphery, Second threaded holes are uniformly arranged around the second connecting end plate 13, and the first threaded holes are provided in one-to-one correspondence with the second threaded holes, and the third high-strength bolts 14 pass through the first threaded holes in turn. holes and the second threaded holes, so as to fixedly connect the first connecting end plate 12 and the second connecting end plate 13 together.

In the present utility model, the buckling support unit includes a core plate 1, a first outer constraint cover plate 2, a second outer constraint cover plate 3, a first backing plate 4, a second backing plate 5 and a plurality of first high-strength bolts 6 , a number of second high-strength bolts 7 , the first stiffener 8 and the second stiffener 9 .

The chip 1 includes a first non-yielding section, a yielding section, and a second non-yielding section arranged in sequence in the axial direction, and the length of the yielding section is 30%-50% of the diagonal length of the frame main body 15; One end of the first non-yielding section is used to connect to one end of the frame body 15, the other end of the first non-yielding section is connected to one end of the yielding section, and the other end of the yielding section is connected to the second non-yielding section. One end of the yielding section is connected, and the other end of the second non-yielding section is vertically fixed to the first connecting end plate 12; wherein, welding is adopted between the second non-yielding section and the first connecting end plate 12 fixed; the first backing plate 4, the yield section and the second backing plate 5 are located in the same plane; wherein, the first backing plate 4 is arranged on one side of the long axis direction of the yield section, and the The second backing plate 5 is arranged on the other side of the long axis direction of the yield section; the first outer constraint cover plate 2, the yield section and the second outer constraint cover plate 3 are arranged in parallel in sequence; wherein, The first outer restraint cover 2 is located on one side of the plane where the yield section is located, and the second outer restraint cover 3 is located on the other side of the plane where the yield section is located.

One side of the first outer constraining cover plate 2, one side of the first backing plate 4 and one side of the second outer constraining cover plate 3 are fixedly connected together by a plurality of first high-strength bolts 6; One side of an outer constraint cover plate 2 is provided with several first bolt holes, and several first bolt holes are evenly arranged along the long axis direction of the first outer constraint cover plate 2; the first backing plate 4 is provided with several Second bolt holes, several second bolt holes are evenly arranged along the long axis direction of the first backing plate 4; one side of the second outer restraint cover plate 3 is provided with some third bolt holes, several third bolt holes Evenly arranged along the long axis direction of the second outer restraint cover plate 3; wherein, the first bolt hole, the second bolt hole and the third bolt hole are set in one-to-one correspondence, and the first high-strength bolt 6 through the first bolt hole, the second bolt hole and the third bolt hole in sequence, and connect one side of the first outer restraint cover 2, the first backing plate 4 and the second One side of the outer constraining cover plate 3 is fixedly connected together.

The other side of the first outer restraint cover plate 2, the second backing plate 5 and the other side of the second outer restraint cover plate 3 are fixedly connected together by a plurality of second high-strength bolts 7; The other side of the first outer constraining cover plate 2 is provided with a number of fourth bolt holes, and several fourth bolt holes are evenly arranged along the long axis direction of the first outer constraining cover plate 2; on the second backing plate 5 Several fifth bolt holes are arranged, and several fifth bolt holes are evenly arranged along the long axis direction of the second backing plate 5; The sixth bolt holes are evenly arranged along the long axis direction of the second outer constraining cover plate 3; wherein, the fourth bolt holes, the fifth bolt holes and the sixth bolt holes are set in one-to-one correspondence, and the The second high-strength bolt 7 passes through the fourth bolt hole, the fifth bolt hole and the sixth bolt hole in sequence, and connects the other side of the first outer restraint cover plate 2 and the first backing plate 4 and the other side of the second outer constraining cover 3 are fixedly connected together.

The first stiffener 8 is symmetrically arranged on the central axis of both sides of the first non-yielding section, and the first stiffener 8 is fixed vertically to the first non-yielding section; the second stiffener 9 is symmetrical The second stiffener 9 is vertically fixed to the second non-yielding section and arranged on the central axis of both sides of the second non-yielding section.

In the utility model, the rigid support unit includes a square steel pipe 10 and an end welding plate 11; one end of the square steel pipe 10 is vertically fixedly connected with the second connecting end plate 12, and the other end of the square steel pipe 10 is connected with the second connecting end plate 12. One side of the end welding plate 11 is fixedly connected, and the other side of the end welding plate 11 is provided with a connecting ear plate for connecting with the other end of the frame main body 15; wherein, the second connecting end plate 12 is connected with The square steel pipes 10 are fixed by welding, and the square steel pipes 10 and the end welding plates 11 are fixed by welding.

designing process:

The hybrid buckling-constrained support described in the utility model needs to determine the length of the yield section and the section parameters of the square steel pipe before processing; the specific process is as follows:

Step 1. Select a suitable frame body and determine its section properties.

Step 2. Determine the length of the yield section according to the selected frame body and its section properties and seismic design requirements; preferably, the length of the yield section is 30%-50% of the diagonal length of the frame body , to obtain the design result of the buckling brace unit;

Step 3. Calculate the maximum bearing capacity of the buckling bracing unit according to the design result of the buckling bracing unit.

Step 4. Determine the cross-sectional size of the square steel pipe according to the maximum bearing capacity of the buckling support unit, so as to ensure that the square steel pipe will neither yield in tension nor buckle in compression under the maximum bearing capacity of the buckling support unit, and obtain rigidity Design results for support elements.

Step 5. According to the design result of the buckling support unit and the design result of the rigid support unit, check and calculate the bearing capacity of the hybrid buckling-constrained support.

Assembly process:

The assembly process of the hybrid buckling restraint support described in the present invention is as follows:

The first stiffener and the second stiffener are respectively welded on the central axis of the non-yielding section at both ends of the core plate; the first outer restraint cover, the first backing plate and the second outer restraint cover are fixedly connected by the first high-strength bolts Together, the first outer restraint cover plate, the second backing plate and the second outer restraint cover plate are fixedly connected together by the second high-strength bolts to obtain a buckling support unit; the end welding plate is welded and fixed on one end of the square steel pipe part to obtain a rigid support unit; the first connecting end plate and the second non-yielding section end of the core plate are welded and fixed, and the second connecting end plate is welded and fixed on the other end of the square steel pipe; the third high-strength bolt is used to The first connecting end plate and the second connecting end plate are fixedly connected together, so that the buckling support unit and the rigid support unit are fixedly connected together; so far, the assembly of the hybrid buckling-constrained support is completed.

The hybrid buckling-constrained support described in the utility model is usually arranged along the diagonal of the frame main body compared with the traditional buckling-constrained support, which adopts the method of connecting the buckling support unit and the rigid support unit in series, which reduces the yield section in the buckling support unit The length of the buckling bracing unit adopts an all-steel assembleable structure, and by reducing the length of the yield section, the buckling bracing unit dissipates the seismic input energy through greater yield deformation; secondly, by introducing square steel pipes As a rigid support unit, for the design of the square steel pipe, it should be satisfied that under the maximum expected load of the buckling support unit, it will neither yield in tension nor buckle in compression, so as to provide backup stiffness for the buckling support unit as a whole; respectively After welding a connecting end plate at the connection end of the buckling bracing unit and the rigid bracing unit, the hybrid buckling constrained support can be obtained by connecting with high-strength bolts; while improving the seismic performance of the buckling constrained bracing frame structure, the interlayer deformation of the frame structure is improved. large disadvantages, so that the hybrid buckling restraint support can be applied in the frame structure building, and realize the function of repairing after the earthquake; the utility model fully utilizes the characteristics of the assembled structure, and the construction site only needs to assemble the The hybrid buckling-restrained braces are bolted to the frame body, and each component is produced and assembled in the factory.

In the utility model, designers can flexibly arrange the length of the yield section according to the shock absorption requirements of the structure, and give full play to the superior plastic deformation and energy dissipation capacity of steel in the buckling-constrained bracing frame structure, thereby reducing the impact on the main structure during earthquakes. damage; the replaceability and operability of the buckling bracing units located within the finite length of the diagonal of the frame body after the earthquake is simpler than that of the full-length heavy buckling-restrained braces occupying the entire frame; It can provide greater rigidity for the structure; the length of the yield section can be reduced by connecting square steel pipes in series in the buckling support unit, and the length of the buckling support unit directly affects the amount of material used in it, which greatly saves construction costs;

The hybrid buckling-constrained support described in the utility model has good support performance, better seismic performance and replaceability than the traditional BRB, and has good application scenarios; the hybrid buckling-constrained support that can be assembled to reduce the length of the yield section can make steel Give full play to its plastic deformation ability, greatly increase the support stiffness to reduce the interstory displacement of the structure; the square steel pipe provides backup stiffness for the support, and the buckling restraint support part that reduces the length of the yield section helps the component to be replaced after the earthquake ; For the processing process of the hybrid buckling restraint support, most of its procedures can be prefabricated in the factory, and the site only needs to bolt the hybrid buckling restraint support to the frame body, which is convenient for construction, can greatly improve the construction quality, shorten the construction period, and meet the requirements of assembly The concept of traditional building; few components, easy to process, simple structure, can give full play to the performance of steel.

The above-mentioned embodiment is only one of the implementations that can realize the technical solution of the utility model, and the scope of protection claimed by the utility model is not only limited by the embodiment, but also includes within the technical scope disclosed in the utility model, any Variations, substitutions and other implementations can easily occur to those skilled in the art.

Claims (8)

1. A hybrid buckling-restrained brace, characterized in that the hybrid buckling-restrained brace is disposed obliquely in a diagonal direction of a frame body (15); the hybrid buckling restrained brace comprises a buckling bracing unit and a rigid bracing unit which are coaxially connected;

the first end of the buckling supporting unit is used for being connected with one end of the frame main body (15), the second end of the buckling supporting unit is connected with the first end of the rigid supporting unit, and the second end of the rigid supporting unit is used for being connected with the other end of the frame main body (15); the buckling support unit is detachably and fixedly connected with the rigid support unit.

2. The hybrid buckling-restrained brace according to claim 1, wherein the buckling-restrained brace unit comprises a core plate (1), a first outer restraining cover plate (2), a second outer restraining cover plate (3), a first base plate (4), a second base plate (5), a plurality of first high-strength bolts (6) and a plurality of second high-strength bolts (7);

the core plate (1) comprises a first non-yielding section, a yielding section and a second non-yielding section which are sequentially arranged in the axial direction, and the first base plate (4), the yielding section and the second base plate (5) are positioned in the same plane; the first base plate (4) is arranged on one side of the yield section in the long axis direction, and the second base plate (5) is arranged on the other side of the yield section in the long axis direction; the first external constraint cover plate (2), the yield section and the second external constraint cover plate (3) are sequentially arranged in parallel; wherein the first external constraint cover plate (2) is positioned on one side of the plane of the yield section, and the second external constraint cover plate (3) is positioned on the other side of the plane of the yield section;

one side of the first external restraint cover plate (2), one side of the first base plate (4) and one side of the second external restraint cover plate (3) are fixedly connected together through a plurality of first high-strength bolts (6); the other side of the first external restraint cover plate (2), the second base plate (5) and the other side of the second external restraint cover plate (3) are fixedly connected together through a plurality of second high-strength bolts (7).

3. The hybrid buckling restrained brace according to claim 2, wherein a plurality of first bolt holes are formed in one side of the first outer restraining cover plate (2), and are uniformly distributed along the long axis direction of the first outer restraining cover plate (2); a plurality of second bolt holes are formed in the first base plate (4), and are uniformly distributed along the long axis direction of the first base plate (4); a plurality of third bolt holes are formed in one side of the second external restraint cover plate (3), and are uniformly distributed along the long axis direction of the second external restraint cover plate (3);

the first bolt hole, the second bolt hole and the third bolt hole are arranged in a one-to-one correspondence mode, the first high-strength bolt (6) penetrates through the first bolt hole, the second bolt hole and the third bolt hole in sequence, and one side of the first external constraint cover plate (2) and one side of the first base plate (4) and one side of the second external constraint cover plate (3) are fixedly connected together.

4. The hybrid buckling restrained brace according to claim 2, wherein a plurality of fourth bolt holes are formed in the other side of the first outer restraining cover plate (2), and are uniformly distributed along the long axis direction of the first outer restraining cover plate (2); a plurality of fifth bolt holes are formed in the second base plate (5), and are uniformly distributed along the long axis direction of the second base plate (5); a plurality of sixth bolt holes are formed in the other side of the second external restraint cover plate (3), and are uniformly distributed along the long axis direction of the second external restraint cover plate (3);

the fourth bolt hole, the fifth bolt hole and the sixth bolt hole are arranged in a one-to-one correspondence mode, and the second high-strength bolt (7) penetrates through the fourth bolt hole, the fifth bolt hole and the sixth bolt hole in sequence to fixedly connect the other side of the first external constraint cover plate (2) and the other sides of the first base plate (4) and the second external constraint cover plate (3) together.

5. A hybrid buckling-restrained brace according to claim 2, wherein the buckling-restrained brace unit further comprises a first stiffener (8) and a second stiffener (9);

the first stiffening ribs (8) are symmetrically arranged on central axes at two sides of the first non-yielding section, and the first stiffening ribs (8) are vertically fixed with the first non-yielding section; the second stiffening ribs (9) are symmetrically arranged on central axes at two sides of the second non-yielding section, and the second stiffening ribs (9) are vertically fixed with the second non-yielding section.

6. A hybrid buckling-restrained brace according to claim 2, wherein the length of the yielding section is 30-50% of the diagonal length of the frame body (15).

7. A hybrid buckling-restrained brace according to claim 1, further comprising a first connecting end plate (12) and a second connecting end plate (13) arranged in parallel;

the first connecting end plate (12) is vertically fixed at the second end of the buckling-restrained brace unit, and the second connecting end plate (13) is vertically fixed at the first end of the rigid brace unit; the first connecting end plate (12) and the second connecting end plate (13) are fixedly connected together by a third high-strength bolt (14).

8. A hybrid buckling-restrained brace according to claim 1, wherein the rigid supporting unit comprises a square steel tube (10) and an end welded plate (11); one end of the square steel pipe (10) is connected with the second end of the buckling support unit, the other end of the square steel pipe (10) is fixedly connected with one side of the end welding plate (11), and the other side of the end welding plate (11) is used for being connected with the other end of the frame main body (15).

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