Connection joint and design method of strong-beam weak-column transfer beam and steel reinforced concrete column

Abstract

The application discloses a strong-beam-weak-column type conversion beam and steel reinforced concrete column connecting joint and a design method, and belongs to the technical field of building structure engineering, and solves the problems of construction difficulty of the existing conversion beam and column joint and easy concrete pouring quality problems. The connecting joint comprises a reinforced concrete column and a reinforced concrete beam, the reinforced concrete column is provided with a first steel along an axial direction, and the first steel extends to the reinforced concrete beam at an upper end, a plurality of column longitudinal reinforcements arranged in the axial direction are arranged in the reinforced concrete column, the column longitudinal reinforcements are provided with continuous composite rectangular spiral hoops connected therewith, and a connecting plate is arranged outside the steel at a connecting joint of the reinforced concrete column and the reinforced concrete beam. The strong-beam-weak-column type conversion beam and steel reinforced concrete column connecting joint and the design method can meet the bearing capacity, facilitate the construction of the conversion beam and the steel reinforced concrete column joint, and thus guarantee the concrete pouring quality of the joint.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building structure engineering, and particularly relates to a weak-column strong-beam type transfer beam and a design method of a steel reinforced concrete column connecting joint. BACKGROUND

[0002] With the improvement of social economy, the building function is more and more complex, and the weight supported by the transfer beam is sometimes very large. For example, some of the full-frame shear wall structures of the subway vehicle bases that have been built have reached 150m high, and the transfer beam needs to support the weight of more than 40 layers of buildings. Due to the use function requirements of the vehicle base, the span reaches about 18m, resulting in a very large cross section of the transfer beam and a very high flexural capacity, which cannot achieve the "strong column weak beam".

[0003] The steel reinforced concrete structure has high bearing capacity and good seismic ductility, but the construction of the beam-column joint is complex, which often causes headaches to the construction unit. For the steel reinforced concrete structure with high bearing capacity of the transfer beam, it is impossible to achieve the "strong column weak beam", and the only way is to increase the longitudinal reinforcement of the transfer column and increase the width of the steel flange. However, this method still cannot achieve the "strong column weak beam", and it also leads to excessive longitudinal reinforcement of the column and excessive width of the steel flange in the column, resulting in construction difficulties of the transfer beam-column joint and easily causing concrete pouring quality problems. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a strong-beam weak-column type transfer beam and a design method of a steel reinforced concrete column connecting joint, which can solve the above problems of the prior art, facilitate the construction of the transfer beam and the steel reinforced concrete column joint, and guarantee the concrete pouring quality of the joint, thereby having the characteristics of convenient use and strong practicability.

[0005] The technical solution adopted by the present application is: a strong-beam weak-column type transfer beam and a steel reinforced concrete column connecting joint, comprising a reinforced concrete column and a reinforced concrete beam, a first steel is arranged in the reinforced concrete column along the axial direction, characterized in that the upper end of the first steel extends into the reinforced concrete beam, a plurality of column longitudinal reinforcements are arranged in the reinforced concrete column along the axial direction, a continuous composite rectangular spiral stirrup connected with the column longitudinal reinforcement is arranged on the column longitudinal reinforcement, a connecting plate is arranged outside the steel on the connecting joint of the reinforced concrete column and the reinforced concrete beam, beam longitudinal reinforcements are arranged in the reinforced concrete beam, the beam longitudinal reinforcements are connected with the first steel through the connecting plate, and a composite stirrup is arranged on the beam longitudinal reinforcements.

[0006] As a further improvement, a second steel is arranged in the reinforced concrete beam along the axial direction, and a stud is arranged between the second steel and the beam longitudinal reinforcement.

[0007] Further, a weldable mechanical connecting sleeve is arranged outside the steel on the connecting joint of the reinforced concrete column and the reinforced concrete beam.

[0008] Furthermore, stiffening ribs are provided on the inner sides of the first and second steel sections at the connection nodes of the reinforced concrete columns and reinforced concrete beams.

[0009] Furthermore, composite stirrups are provided on the longitudinal reinforcement bars of the columns within the reinforced concrete beam.

[0010] Furthermore, the upper end of the reinforced concrete column is provided with a wire mesh, and the upper end of the wire mesh extends into the reinforced concrete beam.

[0011] Furthermore, the continuous composite rectangular spiral hoop includes an outer spiral hoop, an inner spiral hoop, and a single-limb hoop. The outer spiral hoop is arranged on the outside of the column longitudinal reinforcement, the inner spiral hoop is arranged on the inside of the column longitudinal reinforcement, and the single-limb hoop is arranged on the two column longitudinal reinforcements at the right angle.

[0012] Furthermore, the surface of the reinforced concrete column is provided with a mortar layer.

[0013] Furthermore, the first type of steel has a cross-shaped cross section, and each of the ribs of the first type of steel is provided with a flange plate.

[0014] The design method for the connection node between the strong beam-weak column type transfer beam and the steel-concrete composite column includes the following steps:

[0015] (1) Calculate the longitudinal reinforcement and steel section of the steel-concrete column according to the current specifications, but do not adjust the column top bending moment value of the seismic action combination according to the relevant regulations. If the obtained column longitudinal reinforcement and steel section are convenient for the construction of the transfer beam and column joint, and convenient for the placement of continuous composite rectangular spiral hoops, the column longitudinal reinforcement and steel section shall be taken as above, and step 2 below shall be skipped.

[0016] (2) Calculate the longitudinal reinforcement and steel section of the steel-concrete column according to the provisions of the current specifications, but do not adjust the column top bending moment value of the seismic action combination according to the relevant provisions. The resulting column longitudinal reinforcement and steel section are still too large or too large, which is not convenient for the construction of the transfer beam and column joint, and is not convenient for the placement of continuous composite rectangular spiral hoops. Calculate the column longitudinal reinforcement and steel section according to the standard value of the effect of the load and seismic action combination, i.e., formula (1), and do not adjust the column top bending moment value of the seismic action combination according to the relevant provisions.

[0017] S GE +γ Eh S Ehk +γ Ev S Evk +ψ w γ w S wk ≤R(1)

[0018] In the formula: S GE The effect of the representative value of gravity load; S Ehk SEvk The effects are divided into the standard values ​​of horizontal and vertical seismic forces; S wk The effect of the standard value of wind load; ψ w γ is the combination coefficient for wind load; Eh γ Ev γ w These are the partial factors for horizontal seismic action, vertical seismic action, and wind load, respectively; R is the design resistance value of the structural member; γ Eh γ Ev γ w ψ w All values ​​are taken according to current standards, but when the value is greater than 1.0, it is taken as 1.0;

[0019] (3) Calculate the stirrups of the steel-concrete composite column in the transfer layer according to the current specifications. The stirrups in the column shall be continuous composite rectangular spiral stirrups with excellent stress performance.

[0020] (4) For stirrups in reinforced concrete beams and reinforced concrete column joints: When the reinforced concrete beam does not have a second type of steel, a continuous composite rectangular spiral stirrup is used. When the reinforced concrete beam has a second type of steel, due to the obstruction of the steel in the beam, a normal composite stirrup is used.

[0021] Beneficial effects

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1. Compared with the existing general transfer beam-steel-concrete column connection nodes, the ductility of the concrete transfer column is increased by setting steel sections, continuous composite rectangular spiral hoops, and surface wire mesh. While meeting the bearing capacity requirements, the number of longitudinal reinforcement bars in the column and the width of the steel flange are reduced, which facilitates the construction of the transfer beam-steel-concrete column node and ensures the quality of the concrete pouring at the node.

[0024] 2. Compared with existing general steel-concrete composite columns, by setting up wire mesh, the concrete and soil can be prevented from falling off prematurely during an earthquake, and the ductility and energy dissipation capacity of the column top can be enhanced.

[0025] 3. Compared with existing general reinforced concrete columns, by setting steel sections and composite rectangular spiral hoops inside the column, the steel sections can reduce the axial compression ratio of the concrete column, and the continuous composite rectangular spiral hoops reduce the number of stirrup joints, thereby increasing the column's bearing capacity, ductility, and energy dissipation capacity. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the main structure of Embodiment 1 of the present invention;

[0027] Figure 2 for Figure 1 Enlarged cross-sectional view at point AA;

[0028] Figure 3 for Figure 1 Enlarged cross-sectional view at point BB;

[0029] Figure 4 This is a schematic diagram of the main structure of Embodiment 2 of the present invention;

[0030] Figure 5 for Figure 4 Enlarged cross-sectional view at the CC section;

[0031] Figure 6 This is an enlarged schematic diagram of the outer spiral hoop structure in this invention;

[0032] Figure 7 This is an enlarged schematic diagram of the inner spiral hoop structure in this invention;

[0033] Figure 8 This is an enlarged schematic diagram of the steel wire mesh facade in this invention.

[0034] Among them: 1-reinforced concrete column, 2-first type steel, 3-reinforced concrete beam, 4-column longitudinal reinforcement, 5-continuous composite rectangular spiral stirrup, 6-wire mesh, 7-beam longitudinal reinforcement, 8-stiffening rib, 9-connecting plate, 10-mortar layer, 11-single leg stirrup, 12-second type steel, 13-composite stirrup, 14-weldable mechanical connection sleeve, 15-stud, 51-outer spiral stirrup, 52-inner spiral stirrup. Detailed Implementation

[0035] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.

[0036] Example 1

[0037] See Figures 1-3 As shown, the strong beam-weak column type transfer beam and steel-concrete column connection node of the present invention includes a reinforced concrete column 1 and a reinforced concrete beam 3. A first steel section 2 is provided axially inside the reinforced concrete column 1. The first steel section 2 extends into the reinforced concrete beam 3. A plurality of axially arranged column longitudinal bars 4 are provided inside the reinforced concrete column 1. A continuous composite rectangular spiral hoop 5 is provided on the column longitudinal bars 4 and connected thereto. A connecting plate 9 is provided on the outside of the first steel section 2 at the connection node between the reinforced concrete column 1 and the reinforced concrete beam 3. A beam longitudinal bar 7 is provided inside the reinforced concrete beam 3. The beam longitudinal bar 7 is connected to the first steel section 2 through the connecting plate 9. A composite hoop 13 is provided on the beam longitudinal bar 7.

[0038] In this embodiment, the longitudinal reinforcement 4 and the first steel section 2 of the steel-concrete column are calculated according to the current specifications. The stirrups of the steel-concrete column in the transfer layer are also calculated according to the current specifications. By setting the first steel section 2, continuous composite rectangular spiral stirrups 5, and wire mesh 6, the ductility of the reinforced concrete column 1 is increased. While meeting the bearing capacity requirements, the number of longitudinal reinforcements and the width of the steel flanges are reduced, which facilitates the construction of the transfer beam-steel-concrete column joint and ensures the quality of the joint concrete pouring. It also creates favorable conditions for using the continuous composite rectangular spiral stirrups 5 with excellent stress performance in the transfer column. The top of the first steel section 2 extends to below the upper longitudinal reinforcement of the reinforced concrete beam, which facilitates the passage of the upper longitudinal reinforcement of the reinforced concrete beam through the joint and facilitates construction. By setting the steel section and the continuous composite rectangular spiral stirrups 4 in the column, the steel section can reduce the axial compression ratio of the concrete column, and the continuous composite rectangular spiral stirrups 4 reduce the stirrup joints, thereby increasing the bearing capacity, ductility, and energy dissipation capacity of the column.

[0039] Example 2

[0040] The difference between this example and Example 1 is that a second steel section 12 is provided axially inside the reinforced concrete beam 3, and a stud 15 is provided between the second steel section 12 and the longitudinal reinforcement 7 of the beam. Weldable mechanical connection sleeves 14 are provided on the outside of the steel section at the connection node between the reinforced concrete column 1 and the reinforced concrete beam 3. The bearing capacity of the reinforced concrete beam 3 can be effectively increased by the second steel section 12. The longitudinal reinforcement 7 of the beam and the longitudinal reinforcement 4 of the column are connected to the steel section by the weldable mechanical connection sleeves 14, which increases the reliability of the connection. The stud 15 enhances the structural connectivity, transfers loads, and improves the overall stability.

[0041] Furthermore, stiffening ribs 8 are provided on the inner sides of the first steel section 2 and the second steel section 12 at the connection node between the reinforced concrete column 1 and the reinforced concrete beam 3. The stiffening ribs 8 prevent local buckling of the steel sections and enhance the shear bearing capacity of the joint area.

[0042] Furthermore, composite stirrups 13 are provided on the longitudinal reinforcement 4 of the column in the reinforced concrete beam 3. Due to the obstruction of the steel in the beam, the use of composite stirrups 13 can effectively avoid interference and facilitate construction.

[0043] Furthermore, a wire mesh 6 is provided at the upper end of the reinforced concrete column 1, and the upper end of the wire mesh 6 extends into the reinforced concrete beam 3. The wire mesh 6 is woven from galvanized steel wire with a diameter of 4mm to 6mm and a mesh spacing of 50mm to 100mm. The wire mesh 6 prevents premature concrete detachment during earthquakes and enhances the ductility and energy dissipation capacity of the column base. To facilitate concrete pouring, the wire mesh is placed on the surface of the concrete component. The diameter of the wire has been designed to allow for corrosion, and a 20mm to 30mm thick mortar layer is applied to the surface of the wire for protection.

[0044] Furthermore, the continuous composite rectangular spiral stirrup 5 includes an outer spiral stirrup 51, an inner spiral stirrup 52, and a single-limb stirrup 11. The outer spiral stirrup 51 is arranged on the outside of the column longitudinal reinforcement 4, the inner spiral stirrup 52 is arranged on the inside of the column longitudinal reinforcement 4, and the single-limb stirrup 11 is arranged on the two column longitudinal reinforcement 4 at the right angle. The use of double spiral stirrups increases the stability of the structure. The continuous composite rectangular spiral stirrup 5 reduces the number of stirrup joints and enhances the load-bearing capacity, ductility, and energy dissipation capacity of the column base.

[0045] Furthermore, a mortar layer 10 is provided on the surface of the reinforced concrete column 1. The mortar layer 10 is a high-performance composite mortar layer, which is applied under pressure to ensure that there are no air bubbles in the high-performance composite mortar and that it is in close contact with the concrete. The mortar layer 10 also protects the wire mesh 6, preventing it from oxidizing and rusting.

[0046] Furthermore, the first steel section 2 has a cross-shaped structure, which provides more stability when connecting complex nodes. The ribs of the first steel section 2 are all provided with flange plates. When subjected to pressure and torque, the flange plates increase the cross-sectional area of ​​the steel section, thereby improving the load-bearing capacity and stiffness of the steel section, and further increasing the stability and safety of the steel structure.

[0047] The design method for the connection node between the strong beam-weak column type transfer beam and the steel-concrete composite column includes the following steps:

[0048] (1) Calculate the longitudinal reinforcement and steel section of the steel-concrete column according to the current specifications, but do not adjust the column top bending moment value of the seismic action combination according to the relevant regulations. If the obtained column longitudinal reinforcement and steel section are convenient for the construction of the transfer beam and column joint, and convenient for the placement of continuous composite rectangular spiral hoops, the column longitudinal reinforcement and steel section shall be taken as above, and step 2 below shall be skipped.

[0049] (2) Calculate the longitudinal reinforcement and steel section of the steel-concrete column according to the provisions of the current specifications, but do not adjust the column top bending moment value of the seismic action combination according to the relevant provisions. The resulting column longitudinal reinforcement and steel section are still too large or too large, which is not convenient for the construction of the transfer beam and column joint, and is not convenient for the placement of continuous composite rectangular spiral hoops. Calculate the column longitudinal reinforcement and steel section according to the standard value of the effect of the load and seismic action combination, i.e., formula (1), and do not adjust the column top bending moment value of the seismic action combination according to the relevant provisions.

[0050] S GE +γ Eh S Ehk +γ Ev S Evk +ψ w γ w S wk ≤R (1)

[0051] In the formula: S GE The effect of the representative value of gravity load; S Ehk SEvk The effects are divided into the standard values ​​of horizontal and vertical seismic forces; S wk The effect of the standard value of wind load; ψ w γ is the combination coefficient for wind load; Eh γ Ev γ w These are the partial factors for horizontal seismic action, vertical seismic action, and wind load, respectively; R is the design resistance value of the structural member; γ Eh γ Ev γ w ψ w All values ​​are taken according to current standards, but when the value is greater than 1.0, it is taken as 1.0;

[0052] (3) Calculate the stirrups in the reinforced concrete column according to the current specifications. The stirrups in the column shall be continuous composite rectangular spiral stirrups with excellent stress performance.

[0053] (4) For stirrups in reinforced concrete beams and reinforced concrete column joints: When the reinforced concrete beam does not have a second type of steel, a continuous composite rectangular spiral stirrup is used. When the reinforced concrete beam has a second type of steel, due to the obstruction of the steel in the beam, a normal composite stirrup is used.

[0054] In this embodiment, by calculating the longitudinal reinforcement, steel section, and internal stirrups of the steel-concrete composite column, the minimum steel section and the fewest longitudinal reinforcements are achieved. This facilitates the placement of continuous composite rectangular spiral stirrups or reduces the bottom reinforcement of the transfer beam, preventing the column steel flange from passing through the joint area. The longitudinal reinforcement of the steel-concrete composite transfer column is calculated based on the combined effects of load and seismic action, but the design value of the column top bending moment under the combined seismic action is not adjusted according to relevant regulations. That is, the "strong column, weak beam" seismic resistance requirement is not met. Instead, the ductility of the concrete transfer column is increased by setting steel sections, continuous composite rectangular spiral stirrups, and surface wire mesh. Because this approach reduces the number of longitudinal reinforcements and the width of the steel flange, it facilitates the construction of the transfer beam-steel-concrete composite column joint and ensures the quality of the joint concrete pouring.

[0055] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A connection joint of a strong beam and weak column type transfer beam and a steel reinforced concrete column, comprising a reinforced concrete column (1) and a reinforced concrete beam (3), a first shaped steel (2) is arranged in the reinforced concrete column (1) along the axial direction, characterized in that, The first type steel (2) extends to the reinforced concrete beam (3), the reinforced concrete column (1) is internally provided with a plurality of column longitudinal reinforcements (4) arranged in the axial direction, the column longitudinal reinforcement (4) is provided with a continuous composite rectangular spiral hoop (5) connected thereto, the first type steel (2) is provided with a connecting plate (9) outside the connecting joint of the reinforced concrete column (1) and the reinforced concrete beam (3), the reinforced concrete beam (3) is internally provided with beam longitudinal reinforcements (7), the beam longitudinal reinforcement (7) is connected with the first type steel (2) through the connecting plate (9), the beam longitudinal reinforcement (7) is provided with a composite stirrup (13), the upper end of the steel mesh (6) extends to the reinforced concrete beam (3), the continuous composite rectangular spiral hoop (5) comprises an outer spiral hoop (51), an inner spiral hoop (52) and a single limb hoop (11), the outer spiral hoop (51) is arranged outside the column longitudinal reinforcement (4), the inner spiral hoop (52) is arranged inside the column longitudinal reinforcement (4), and the single limb hoop (11) is arranged on the two column longitudinal reinforcements (4) at the right angle.

2. The strong beam weak column transfer beam and steel reinforced concrete column connection of claim 1, wherein, The reinforced concrete beam (3) is internally provided with a second type steel (12) arranged in the axial direction, and the second type steel (12) is provided with a stud (15) between the beam longitudinal reinforcement (7).

3. The strong beam weak column transfer beam and steel reinforced concrete column connection of claim 2, wherein, The connecting joint of the reinforced concrete column (1) and the reinforced concrete beam (3) is provided with a weldable mechanical connecting sleeve (14) outside the type steel.

4. The strong beam weak column transfer beam and steel reinforced concrete column connection joint according to claim 1 or 2, characterized in that, The connecting joint of the reinforced concrete column (1) and the reinforced concrete beam (3) is provided with a stiffening rib (8) inside the first type steel (2) and the second type steel (12).

5. The strong beam weak column transfer beam and steel reinforced concrete column connection of claim 2, wherein, The column longitudinal reinforcement (4) in the reinforced concrete beam (3) is provided with a composite stirrup (13).

6. The strong beam weak column transfer beam and steel reinforced concrete column connection of claim 1 or 2, wherein, The surface of the reinforced concrete column (1) is provided with a mortar layer (10).

7. The strong beam weak column transfer beam and steel reinforced concrete column connection of claim 1, wherein, The first type steel (2) has a cross-shaped structure, and the rib plate of the first type steel (2) is provided with a flange plate.

8. The design method of strong beam weak column type transfer beam and steel reinforced concrete column connection joint according to claim 2, characterized in that, The method comprises the following steps: (1) the column longitudinal reinforcement and the type steel section are calculated according to the current specification, but the column top bending moment value combined with the earthquake action is not adjusted according to the relevant provisions, if the column longitudinal reinforcement and the type steel section obtained are convenient for the construction of the transfer beam and the column joint, and convenient for the placement of the continuous composite rectangular spiral hoop, the column longitudinal reinforcement and the type steel section are calculated according to the above values, and the following step 2 is omitted; (2) the column longitudinal reinforcement and the type steel section are calculated according to the current specification, but the column top bending moment value combined with the earthquake action is not adjusted according to the relevant provisions, if the column longitudinal reinforcement and the type steel section obtained are still more or larger, and are not convenient for the construction of the transfer beam and the column joint, and are not convenient for the placement of the continuous composite rectangular spiral hoop, the column longitudinal reinforcement and the type steel section are calculated according to the effect standard value of the load and the earthquake action combination, and the column top bending moment value combined with the earthquake action is not adjusted according to the relevant provisions; (1) In the formula: S GE Effect of the representative value of the gravity load; S Ehk , S Evk Effect of the standard value of the horizontal and vertical earthquake action; S wk Effect of the standard value of the wind load; (3) the stirrup in the reinforced concrete column is calculated according to the current specification, and the stirrup in the reinforced concrete column is in the form of a continuous composite rectangular spiral hoop with excellent stress performance. w Combination value coefficient of the wind load; ​ Eh , ​ Ev , ​ w The partial coefficients of the horizontal earthquake action, the vertical earthquake action and the wind load respectively; R Design value of the resistance of the structural member; ​ Eh , ​ Ev , ​ w , ​ w All are taken according to the current standard, but are taken as 1.0 when greater than 1.0; ​ (4) For the inner stirrup of the joint of reinforced concrete beam and column: when the reinforced concrete beam is not provided with the second type steel, the continuous composite rectangular spiral stirrup is adopted; when the reinforced concrete beam is provided with the second type steel, the common composite stirrup is adopted due to the obstruction of the beam inner type steel.

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