H-shaped steel partially filled concrete composite column-reinforced concrete beam joint and its design method

Abstract

The H-shaped steel partially filled concrete composite column-reinforced concrete beam node and its design method include a partially filled composite column filled with concrete between the flanges of the H-shaped steel (or I-shaped steel) and a reinforced concrete beam with an end plate at the end, the beam in the strong axis direction of the column is connected to the column flange through a bolted end plate, and the beam in the weak axis direction of the column is connected to the plate pre-welded between the two wings of the column through a bolted end plate; when the partially filled composite column is processed and manufactured, the filled concrete at the node area is poured after the beam and column are installed on site. The present invention also includes a design and calculation method for the above-mentioned node. Based on the basic theory of seismic resistance of steel structure, composite structure, concrete structure, and building structure, the present invention provides a new type of beam-column node and its design method for assembled multi-story building structures.

Description

Technical Field

[0001] The invention relates to the field of civil engineering steel structure design. Based on the basic theories of steel structure and composite structure, a composite column-reinforced concrete beam node suitable for assembled multi-story buildings and a design method thereof are proposed. Background Art

[0002] In the context of building industrialization, the structural system of multi-story buildings using steel-concrete composite columns and reinforced concrete beams has many advantages: it can better realize the seismic design concept of "strong columns and weak beams", has better fire resistance and anti-corrosion performance than steel structures, and has better seismic performance than prefabricated concrete structures. However, ordinary H-shaped steel concrete columns have the disadvantages of relatively large amount of formwork (equivalent to reinforced concrete columns), complex connection nodes between prefabricated composite columns and prefabricated concrete beams, and relatively poor reliability. Summary of the invention

[0003] The present invention aims to overcome the above-mentioned shortcomings of the prior art and proposes a partially filled composite column-reinforced concrete beam node and a design method thereof.

[0004] The partially filled composite column of the present invention refers to a column that is filled with concrete between the flanges of an H-steel (or an I-steel), and is provided with longitudinal reinforcement in the weak axis direction of the H-steel, and connecting rods (made of steel bars) are arranged between the flanges of the H-steel. Compared with conventional steel-concrete composite structures, this partially filled composite structure has the advantages of a high degree of prefabrication of components, convenient node connection, and low formwork usage. The beam of the present invention is a reinforced concrete beam with a section of H-steel (with a steel end plate) extending from the end. The prefabricated beam-column node of the present invention is a connection between the reinforced concrete beam and the composite column through an end plate and bolts, and its connection properties are typical steel structure connections, which overcomes the shortcomings of complex connection nodes and poor reliability of prefabricated reinforced concrete structures.

[0005] The H-shaped steel partially filled concrete composite column-reinforced concrete beam node is used for multi-story prefabricated building structures, and is characterized in that it includes a partially filled composite column filled with concrete between the flanges of the H-shaped steel or I-shaped steel and a concrete beam with a steel end plate at the end, the concrete beam in the strong axis direction of the H-shaped steel of the composite column is connected to the H-shaped steel flange of the composite column through bolts and end plates, the concrete beam in the weak axis direction of the H-shaped steel of the composite column is connected to the node plate of the column through end plates and bolts, the two sides of the node plate are welded to the H-shaped steel flange of the composite column, and the middle is welded to the H-shaped steel web of the composite column through stiffening ribs; the H-shaped steel of the concrete beam includes the H-shaped steel inserted into the concrete beam and the beam end H-shaped steel outside the concrete beam, the beam end H-shaped steel is connected to the end plate, a web is provided between the two flanges of the shallower inserted portion of the H-shaped steel inserted into the concrete beam, and no web is provided between the two flanges of the deeper inserted portion; the concrete is the concrete that fills the node area after the concrete beam and the composite column are assembled.

[0006] The H-steel of the composite column is equipped with longitudinal reinforcement in the weak axis direction, and X-shaped tie rods or connecting rods are arranged between the H-steel flanges of the composite column.

[0007] The above-mentioned partially filled concrete composite column-reinforced concrete beam connection node and design method thereof which can be used for multi-story assembled buildings include the following steps:

[0008] Step S1, based on the basic theory of steel structure and concrete structure, preliminarily select the H-shaped steel section and reinforced concrete beam section of the partially filled composite column, perform overall structural analysis and calculation according to the composite column-concrete beam, verify the stability of the composite column based on the calculated component internal force, calculate the longitudinal reinforcement, and design the cross-sectional size and reinforcement of the reinforced concrete beam. The beam has a section of H-shaped steel with a steel end plate at the end, and the design value of the bending yield bearing capacity of the H-shaped steel is M sby Should be greater than the bending bearing capacity M of the reinforced concrete beam calculated based on the actual reinforcement ub , ensuring that the failure of the beam occurs in the reinforced concrete part.

[0009] Step S2: Based on the theoretical value of the full-section yield moment M of the H-beam at the end of the beam sbu Calculate and determine the total tension T=M on the bolt groups near the upper and lower flanges of the H-beam sbu / h b1 , design the bolt diameter d according to the tension T b , the number of bolts n and their arrangement, where h b1 It is the distance from the middle to the middle of the upper and lower flanges of the H-shaped steel at the end of the beam.

[0010] Step S3, according to the minimum operating space required for bolting of beam and column assembly, determine the distance from the concrete end of the beam to the steel end plate, and the distance from the bolt center to the flange of the H-shaped steel at the beam end, determine the length and width of the steel end plate according to the bolt arrangement, set stiffening ribs on the steel end plate, and divide the steel end plate into grids according to different support conditions, calculate the plate thickness required for each grid according to steel structure theory, and take the maximum value as the steel end plate thickness t p ;

[0011] Step S4, when processing and manufacturing the composite column, a node plate with bolt holes and stiffening ribs is set in the weak axis direction of the H-shaped steel in the column to connect the reinforced concrete beam. The width of the node plate is the same as the cross-sectional height of the H-shaped steel column. The two sides of the node plate are welded to the two flanges of the H-shaped steel column, and the middle is welded to the web of the H-shaped steel through the stiffening ribs. In addition to being used to connect the beam in the weak axis direction, the node plate also plays a role in ensuring that the beam-column node domain has sufficient shear bearing capacity; the longitudinal reinforcement of the composite column is calculated according to the internal force diagram of the column obtained by the overall structural analysis, and the transverse reinforcement connecting the two flanges of the H-shaped steel in the composite column adopts the X-shaped tie rod proposed in the document "Experimental Study on Seismic Performance of Partial Composite Beams Filled with Concrete Between H-shaped Steel Flanges" (Journal of Building Structures, September 2015, pages 330-336). The concrete in the beam-column connection node domain needs to be poured and filled again after the beam and column are assembled on site;

[0012] Step S5: When processing and manufacturing reinforced concrete beams, bolts are welded on the H-shaped steel whose ends are embedded in concrete. The arrangement and number of the bolts and the embedding length l of the H-shaped steel are determined. b3 The shear force between concrete and steel should be fully transferred, and the shear force should be conservatively calculated based on the tensile force f when the actual longitudinal reinforcement of the beam yields. y A s Calculation is performed to fully transfer the bending moment and shear force of the concrete beam to the H-shaped steel beam section connected to the composite column. In addition, the beam can be considered to be b0 Divided into about l b0 / 3 and 2l b0 / 3 The two parts are provided with a post-cast strip, so that they can better adapt to on-site assembly construction - for example, the vertical inclination error of columns in high-rise buildings causes a deviation between the actual span of the beam and the designed span.

[0013] Preferably, in step S1, the H-shaped steel and longitudinal reinforcement of the composite column, the cross-sectional dimensions and reinforcement of the concrete beam are designed according to the internal force envelope diagram calculated for the composite column-reinforced concrete beam structure. In order to facilitate the assembly of the concrete beam and the composite column on site, an H-shaped steel with a steel end plate is provided at the end of the beam, and the design value of the bending yield bearing capacity of the H-shaped steel is M sby Should be greater than the bending bearing capacity M of the reinforced concrete beam calculated based on the actual reinforcement ub , to ensure that the failure of the beam occurs in the reinforced concrete part.

[0014] Preferably, in step S2, according to the full-section yield moment theoretical value M of the H-shaped steel at the end of the concrete beam sbu Calculate and determine the total tension T=M on the bolt groups near the upper and lower flanges of the steel section sbu / h b1 , calculate and determine the bolt diameter d based on T b and the number of bolts n and the bolt arrangement, where h b1It is the distance from the middle of the upper and lower flanges of the H-shaped steel.

[0015] Preferably, in step S3, the distance from the concrete end to the end of the beam and the distance from the center of the bolt to the flange of the H-shaped steel at the end of the beam are determined according to the minimum space required for placing a wrench for tightening the bolts, the length and width of the steel end plate of the beam are determined according to the bolt arrangement, stiffening ribs are provided on the steel end plate, and the steel end plate is divided into a two-side support area and a three-side support area according to different support conditions, and the thickness of the end plate of each support grid area is calculated according to the relevant provisions of the "Technical Specification for Steel Structure of Portal Frame Lightweight Houses" (GB51022-2015), as follows:

[0016] The supporting grids on both sides when the end plate is extended: The supporting grids on both sides when the end plates are flush: Three-side support grid: Where f is the design value of the tensile strength of the end plate steel, N1 is the design value of the tensile bearing capacity of a bolt (or anchor), and e f is the distance from the bolt center to the H-beam flange, e w is the distance from the bolt center to the H-beam web, b and b s are the end plate width and stiffener width respectively, and the end plate thickness t ep Take the larger value of t1~t3, and not less than 16mm.

[0017] Preferably, in step S4, a node plate with bolt holes and stiffening ribs is provided in the weak axis direction of the H-shaped steel in the composite column according to the position of the beam to connect the reinforced concrete beam. The width of the node plate is the same as the cross-sectional height of the H-shaped steel column. The two sides of the node plate are welded to the two flanges of the H-shaped steel column, and the middle is welded to the web of the H-shaped steel through the stiffening ribs. In addition to being used to connect the beam in the weak axis direction, the node plate also plays a role in ensuring that the beam-column node domain has sufficient shear bearing capacity; the longitudinal reinforcement in the weak axis direction of the composite column is designed and calculated according to the internal force envelope diagram of the column obtained by the overall structural analysis, and the transverse reinforcement connecting the two flanges of the H-shaped steel in the composite column adopts the X-shaped tie rod proposed in the document "Experimental Study on Seismic Performance of Partial Composite Beams Filled with Concrete Between H-shaped Steel Flanges" (Journal of Building Structures, September 2015, pages 330-336), and the concrete in the beam-column node domain is poured and filled again after the beam and column are assembled on site;

[0018] In step S5, according to the requirement of sufficient transmission of shear force between concrete and steel, the bending moment and shear force of the reinforced concrete beam are fully transmitted to the H-shaped steel beam section connected to the composite column, and the length of the H-shaped steel embedded in the concrete beam and the number of shear studs on the flange of the H-shaped steel n=Q / N are determined. c v , where Q is the shear force, which can be calculated based on the actual longitudinal reinforcement tension limit value fu A s Calculation, N c v is the design value of the shear bearing capacity of a single stud, which is calculated according to the Standard for Design of Steel Structures (GB50017-2017) as follows:

[0019]

[0020] In the formula, E c is the elastic modulus of concrete, A s is the cross-sectional area of ​​the cylindrical head welding nail rod, f c is the design value of concrete compressive strength, f u It is the design value of ultimate tensile strength of cylindrical head weld nail.

[0021] In addition, it is possible to consider b0 Divided into about l b0 / 3 and 2l b0 / 3 The two parts are provided with a post-cast strip, so that they can better adapt to on-site assembly construction - for example, the vertical inclination error of columns in high-rise buildings causes a deviation between the actual span of the beam and the designed span.

[0022] The beneficial effects of the present invention are:

[0023] The present invention is applied to assembled multi-story building structures, and proposes an assembled frame beam-column node. The beam is a prefabricated reinforced concrete beam with a section of H-shaped steel (with an end plate) extending outward at the end, and the column is a prefabricated composite column filled with concrete between the H-shaped steel flanges. The beam and the column are connected by the end plate, the H-shaped steel flange of the composite column (or the node plate with stiffening ribs welded on both sides to the H-shaped steel flange), and bolts. The concrete to be filled in the beam-column node area is poured again after the beam and column are assembled on site. According to the internal forces of the components calculated by the composite column-concrete beam frame structure system, the H-shaped steel and longitudinal reinforcement design of the composite structure and the reinforcement design of the concrete beam are carried out. According to the design value M of the flexural yield bearing capacity of the H-shaped steel sby Greater than the bending bearing capacity M of reinforced concrete beam calculated based on actual reinforcement ub , design the H-beam at the end of the beam. According to the theoretical value of the full-section yield moment M of the H-beam at the end of the beam sbu , design bolts and end plates. According to the position of the H-beam weak-axis beam in the column and the size of the end plate, a node plate with stiffening ribs in the middle is welded to the two flanges and web of the H-beam in the column. The present invention can provide an assembled frame beam-column node with a "strong column and weak beam" and "strong node" seismic design concept, and provides a node design method; the present invention may better solve the problem that the traditional steel frame bolt end plate beam-column connection node is difficult to use in high-rise building structures due to the vertical verticality deviation of the column (the deviation between the actual span of the beam and the designed span). BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1a to Figure 1e is a structural diagram of a reinforced concrete beam in a node of the present invention, wherein Figure 1a is a structural diagram of a reinforced concrete beam in a node of the present invention, Figure 1b yes Figure 1a AA section view, Figure 1c yes Figure 1a BB section view, Figure 1d yes Figure 1a CC section view, Figure 1e yes Figure 1a DD section view.

[0025] Figure 2a to Figure 2c This is a structural diagram of a H-shaped steel partially filled concrete composite column in a node of the present invention, wherein Figure 2a This is a structural diagram of a composite column partially filled with concrete in a node of the present invention. Figure 2b yes Figure 2a EE section view, Figure 2c yes Figure 2a FF section view.

[0026] Figure 3a to Figure 3d Schematic diagram of a partially filled concrete composite column-reinforced concrete beam node (taking a corner column as an example) of the present invention, wherein: Figure 3a is a 3D schematic diagram of a node of the present invention; Figure 3b It is a schematic diagram of the structure of the node of the present invention; Figure 3c yes Figure 3b aa-direction cross-sectional view; Figure 3d yes Figure 3b BB section view.

[0027] Figure 4a to Figure 4c are the end plate grids and related geometric dimensions for different support conditions, where Figure 4a It is the division of the grid when the end plate has no stiffening ribs. Figure 4b It is the division of the grid when only the extending part of the end plate is provided with stiffening ribs. Figure 4c It is the zone division when stiffening ribs are set on the extended part and the interior of the end plate.

[0028] Figure 5 is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0030] Component numbers of the drawings in the specification: concrete beam 1, longitudinal reinforcement of concrete beam 2, stirrups of concrete beam 3, H-shaped steel at beam end 4, end plate of concrete beam 5, stiffening rib of end plate of concrete beam 6, studs in concrete beam 7, flange of H-shaped steel inserted into concrete beam 8, composite column partially filled with concrete 9, H-shaped steel of composite column 10, longitudinal reinforcement of composite column 11, X-shaped tie rod (transverse steel bar) of composite column 12, node plate welded to both flanges of H-shaped steel of composite column 13, stiffening rib of node plate of composite column 14, high-strength bolts 15, end plate outrigger grid 16, end plate two-side support grid 17, end plate three-side support grid 18, end plate ribless grid 19.

[0031] The composite column-concrete beam node of the present invention, in which the concrete beam 1 is connected to the partially filled composite column 9 through the end plate 5 and the bolt 15, can be used for assembled multi-story building structures, and has the advantages of strong nodes, strong columns and weak beams, avoiding on-site welding, and convenient construction. The design and calculation method of such nodes is proposed by using the basic theories of steel structure, concrete structure, composite structure, and structural earthquake resistance.

[0032] The H-shaped steel partially filled concrete composite column-reinforced concrete beam node is used for prefabricated multi-story building structures, including a partially filled composite column 9 filled with concrete between the flanges of the H-shaped steel 10 and equipped with longitudinal reinforcement 11, and a node plate 13 is provided at the position of the beam in the weak axis direction, and a reinforced concrete beam 1 with a section of extended H-shaped steel 4 at the end and connected to the composite column through bolts 15 and an end plate 5.

[0033] The structure of reinforced concrete beams and steel-concrete composite columns conforms to the seismic design concept of "strong columns and weak beams". They have better fire resistance and anti-corrosion properties than steel structures, and better seismic ductility than concrete structures. The seismic design concept of "strong nodes and weak components (beams)" can be achieved by designing the end plates and outward-extending H-shaped steels at the ends of the beams: damage occurs in the concrete away from the beam-column connection.

[0034] The design calculation of the H-shaped steel partially filled concrete composite column-reinforced concrete beam node that can be used in multi-story prefabricated building structures includes the following steps:

[0035] S1, the overall structural analysis and calculation of the composite column-concrete beam is carried out. The stability of the composite column is verified based on the calculated internal force of the component, and the longitudinal reinforcement is calculated, and the cross-sectional size and reinforcement of the reinforced concrete beam are designed. The beam has an H-shaped steel with a steel end plate at the end, and the design value of the flexural yield bearing capacity of the H-shaped steel is M sby Should be greater than the bending bearing capacity M of the reinforced concrete beam calculated based on the actual reinforcement ub , ensuring that the failure of the beam occurs in the reinforced concrete part, the beam of the node of the present invention is shown in Figure 1.

[0036] S2, based on the theoretical value of the full-section yield moment M of the H-shaped steel at the end of the beam sbu Calculate and determine the total tension T=M on the bolt groups near the upper and lower flanges of the H-beam sbu / h b1 , design the bolt diameter d according to the tension T b , the number of bolts n and their arrangement, where h b1 It is the distance from the middle of the upper and lower flanges of the H-shaped steel at the end of the beam.

[0037] S3, according to the minimum operating space required for bolting of beam and column assembly, determine the distance from the concrete end of the beam to the steel end plate, and the distance from the bolt center to the flange of the H-shaped steel at the beam end. According to the bolt arrangement, determine the length and width of the steel end plate, set stiffening ribs on the steel end plate, and divide the steel end plate into grids according to different support conditions. According to the steel structure theory, calculate the plate thickness required for each grid, and take the maximum value as the steel end plate thickness t p ;

[0038] Step S4, when processing and manufacturing the composite column, a node plate with bolt holes and stiffening ribs is set in the weak axis direction of the H-shaped steel in the column to connect the reinforced concrete beam. The width of the node plate is the same as the cross-sectional height of the H-shaped steel column. The two sides of the node plate are welded to the two flanges of the H-shaped steel column, and the middle is welded to the web of the H-shaped steel through the stiffening ribs. In addition to being used to connect the beam in the weak axis direction, the node plate also plays a role in ensuring that the beam-column node domain has sufficient shear bearing capacity; the longitudinal reinforcement of the composite column is calculated according to the internal force diagram of the column obtained by the overall structural analysis, and the transverse reinforcement connecting the two flanges of the H-shaped steel in the composite column adopts the X-shaped tie rod proposed in the document "Experimental Study on Seismic Performance of Partial Composite Beams Filled with Concrete Between H-shaped Steel Flanges" (Journal of Building Structures, September 2015, pages 330-336). The composite column structure is shown in Figure 2, and the concrete in the beam-column connection node domain needs to be poured and filled again after the beam and column are assembled on site. The beam-column connection node is shown in Figure 3;

[0039] Step S5: When processing and manufacturing reinforced concrete beams, bolts are welded on the H-shaped steel whose ends are embedded in concrete. The arrangement and number of the bolts and the embedding length l of the H-shaped steel are determined. b3 The shear force between concrete and steel should be fully transferred, and the shear force should be conservatively calculated based on the tensile force f when the actual longitudinal reinforcement of the beam yields. y A s Calculation is performed to fully transfer the bending moment and shear force of the concrete beam to the H-shaped steel beam section connected to the composite column. In addition, the beam can be considered to be b0 Divided into about l b0 / 3 and 2l b0 / 3 The two parts are provided with a post-cast strip, so that they can better adapt to on-site assembly construction - for example, the vertical inclination error of columns in high-rise buildings causes a deviation between the actual span of the beam and the designed span.

[0040] The present invention is based on the basic earthquake-resistant theories of steel structures, composite structures, concrete structures, and building structures, and realizes the earthquake-resistant design concepts of "strong columns and weak beams" and "strong nodes and weak components (beams)" through reasonable design. The possible failure modes of the nodes of the present invention mainly include bending failure of reinforced concrete beams, tensile failure of bolts, end plate failure (plastic hinge line mode), and shear failure of node areas, and the end plates and other components are designed according to various failure modes. Through reasonable design, the node failure occurs in the reinforced concrete beam part. The present invention provides a new type of beam-column node and its design method for assembled multi-story building structures.

[0041] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. The protection scope of the present invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A design method for a H-shaped steel partially filled concrete composite column-reinforced concrete beam node, which is used for multi-story prefabricated building structures. The H-shaped steel partially filled concrete composite column-reinforced concrete beam node includes a partially filled composite column filled with concrete between the flanges of the H-shaped steel or I-shaped steel and a concrete beam with a steel end plate at the end. The concrete beam in the strong axis direction of the H-shaped steel of the composite column is connected to the H-shaped steel flange of the composite column through bolts and end plates, and the concrete beam in the weak axis direction of the H-shaped steel of the composite column is connected to the node plate of the column through end plates and bolts. The two sides of the node plate are welded to the H-shaped steel flange of the composite column, and the middle is welded to the H-shaped steel web of the composite column through stiffening ribs. The H-shaped steel of the concrete beam includes an H-shaped steel inserted into the concrete beam and an H-shaped steel at the end of the beam outside the concrete beam. The H-shaped steel at the end of the beam is connected to the end plate. A web is provided between the two flanges of the shallower inserted portion of the H-shaped steel inserted into the concrete beam, and no web is provided between the two flanges of the deeper inserted portion. The concrete is the concrete that fills the node area after the concrete beam and the composite column are assembled. The H-beam of the composite column is equipped with longitudinal reinforcement in the weak axis direction and X-shaped tie rods or connecting rods are set between the flanges of the H-beam; Features: The following steps are involved: Step S1, based on the basic theory of steel structure and concrete structure, preliminarily determine the cross section of the H-shaped steel of the partially filled composite column and the cross section of the reinforced concrete beam, analyze and calculate the internal force envelope diagram of the component according to the composite column-concrete beam structure, verify the stability of the composite column according to the internal force and determine the longitudinal reinforcement, design the cross-sectional size and reinforcement of the reinforced concrete beam, the beam has a section of H-shaped steel with a steel end plate at the end to facilitate on-site assembly, and the design value of the bending yield bearing capacity of the H-shaped steel at the beam end is M sby Should be greater than the bending bearing capacity M of the reinforced concrete beam calculated based on the actual reinforcement ub , ensuring that the failure of the beam occurs in the reinforced concrete part; Step S2: Based on the theoretical value of the full-section yield moment M of the H-shaped steel at the end of the beam sbu Calculate and determine the total tension T=M on the bolt groups near the upper and lower flanges of the H-beam sbu / h b1 , design the bolt diameter d according to the tension T b , the number of bolts n and their arrangement, where h b1 It is the distance from the middle of the upper and lower flanges of the H-beam at the end of the beam; Step S3, according to the minimum operating space required for tightening bolts during on-site beam and column assembly, determine the distance from the concrete end of the beam to the steel end plate, and the distance from the bolt center to the flange of the H-shaped steel at the beam end, determine the length and width of the steel end plate of the beam according to the bolt arrangement, set stiffening ribs on the steel end plate, and divide the steel end plate into grids according to different support conditions, calculate the plate thickness required for each grid according to steel structure theory, and take the maximum value as the steel end plate thickness t p ; Step S4, when processing and manufacturing a partially filled steel-concrete composite column, a node plate with bolt holes and stiffening ribs is set in the weak axis direction of the H-shaped steel in the composite column to connect the reinforced concrete beam. The width of the node plate is the same as the cross-sectional height of the H-shaped steel column. The two sides of the node plate are welded to the two flanges of the H-shaped steel column, and the middle is welded to the web of the H-shaped steel through stiffening ribs. In addition to being used to connect the beam in the weak axis direction, the node plate also plays a role in ensuring that the beam-column node domain has sufficient shear bearing capacity; the longitudinal reinforcement in the weak axis direction of the composite column is designed and calculated according to the internal force envelope diagram of the column obtained by the overall structural analysis, and the transverse reinforcement connecting the two flanges of the H-shaped steel in the composite column adopts an X-shaped tie rod, which is arranged at a 45-degree angle, and a certain straight section is set to be welded to the flange, and the tie rod is uninterrupted in its entire length; the concrete in the beam-column connection node domain needs to be poured and filled again after the beam and column are assembled on site; Step S5: When the reinforced concrete beam is processed and manufactured in the factory, the H-shaped steel at the end should be welded with studs. The arrangement and number of studs and the embedded length of the H-shaped steel should ensure that the shear force between the concrete and the steel is fully transmitted. The shear force can be taken as the actual longitudinal reinforcement tension limit value f u A s , so that the bending moment and shear force of the reinforced concrete beam are fully transferred to the H-shaped steel beam section connected to the composite column. In addition, the beam is b0 Divide into l b0 / 3 and 2l b0 / 3 The two parts are provided with a post-cast strip, so that they can better adapt to on-site assembly construction - for example, the vertical inclination error of columns in high-rise buildings causes a deviation between the actual span of the beam and the designed span.

2. The design method according to claim 1, characterized in that: In the step S1, the internal force envelope diagram of the component is obtained by performing overall structural analysis and calculation on the H-shaped steel partially filled concrete composite column-reinforced concrete beam structure, and the H-shaped steel and longitudinal reinforcement in the weak axis direction of the composite column, and the cross-sectional size and reinforcement of the reinforced concrete beam are designed accordingly; a section of H-shaped steel with a steel end plate is provided at the end of the beam to facilitate on-site assembly of the concrete beam and the composite column, and the design value of the bending yield bearing capacity of the H-shaped steel at the beam end is M sby Should be greater than the bending bearing capacity M of the reinforced concrete beam calculated based on the actual reinforcement ub , to ensure that the failure of the beam occurs in the reinforced concrete part.

3. The design method according to claim 1, characterized in that: In step S2, the full-section yield moment theoretical value M of the H-shaped steel at the end of the beam is sbu Calculate and determine the total tension T=M on the bolt groups near the upper and lower flanges of the steel section sbu / h b1 , calculate and determine the bolt diameter d based on T b and the number of bolts n and the bolt arrangement, where h b1 It is the distance from the middle of the upper and lower flanges of the H-shaped steel.

4. The design method according to claim 1, characterized in that: In step S3, the distance from the concrete end of the beam to the steel end plate and the distance from the center of the bolt to the flange of the H-shaped steel at the beam end are determined according to the minimum space required for placing a wrench for tightening the bolts. The length and width of the steel end plate of the beam are determined according to the bolt arrangement. Stiffening ribs are arranged on the steel end plate, and the steel end plate is divided into two-side support areas and three-side support areas according to different support conditions. The thickness of the end plate of each support grid area is calculated according to the relevant provisions of the "Technical Specification for Steel Structure of Portal Frame Lightweight Houses" (GB51022-2015), as follows: The supporting grids on both sides when the end plate is extended: The supporting grids on both sides when the end plates are flush: Three-side support grid: Where f is the design value of the tensile strength of the end plate steel, N1 is the design value of the tensile bearing capacity of a bolt, and e f is the distance from the bolt center to the H-beam flange, e w is the distance from the bolt center to the H-beam web, b and b s are the end plate width and stiffener width respectively, and the end plate thickness t ep Take the larger value of t1~t3, and not less than 16mm.

5. The design method according to claim 1, characterized in that: In the step S4, a node plate with bolt holes and stiffening ribs is arranged in the weak axis direction of the H-shaped steel in the composite column according to the position of the beam to connect the reinforced concrete beam. The width of the node plate is the same as the cross-sectional height of the H-shaped steel column. The two sides of the node plate are welded to the two flanges of the H-shaped steel column, and the middle is welded to the web of the H-shaped steel through the stiffening ribs. In addition to being used to connect the beam in the weak axis direction, the node plate also plays a role in ensuring that the beam-column node domain has sufficient shear bearing capacity; the longitudinal reinforcement in the weak axis direction of the composite column is designed and calculated according to the internal force envelope diagram of the column obtained by the overall structural analysis, and the transverse reinforcement connecting the two flanges of the H-shaped steel in the composite column adopts an X-shaped tie rod, which is arranged at a 45-degree angle, and a certain straight section is arranged to be welded to the flange, and the tie rod is uninterrupted in its entire length; the concrete in the beam-column connection node domain needs to be poured and filled again after the beam and column are assembled on site.

6. The design method according to claim 1, characterized in that: In step S5, a section of H-shaped steel beam is reserved between the steel end plate and the concrete of the beam according to the operating space required for tightening the bolts when assembling the concrete beam and the composite column. According to the requirement of sufficient shear force transmission between the concrete and the steel, the bending moment and shear force of the reinforced concrete beam are fully transmitted to the H-shaped steel beam section connected to the composite column. In this way, the length of the H-shaped steel embedded in the concrete and the number of shear studs on the flange of the H-shaped steel are determined as n=Q / N. c v , where Q is the shear force, which can be calculated based on the actual longitudinal reinforcement tension limit value f u A s Calculation, N c v is the design value of the shear bearing capacity of a single stud, which is calculated according to the Standard for Design of Steel Structures (GB50017-2017) as follows: In the formula, E c is the elastic modulus of concrete, A s is the cross-sectional area of ​​the cylindrical head welding nail rod, f c is the design value of concrete compressive strength, f u It is the design value of the ultimate tensile strength of cylindrical head welding nails; In addition, it is possible to consider b0 Divide into l b0 / 3 and 2l b0 / 3 The two parts are provided with a post-cast strip, so that they can better adapt to on-site assembly construction - for example, the vertical inclination error of columns in high-rise buildings causes a deviation between the actual span of the beam and the designed span.

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