Double replaceable energy-consuming connecting steel column foot structure and design method thereof

Abstract

The application discloses a double replaceable energy dissipation connecting steel column foot structure and a design method thereof, which comprises a steel column, a steel column foot, a double replaceable energy dissipation component and a ground beam; the steel column is connected to the steel column foot through the double replaceable energy dissipation component, and the steel column foot is connected to the ground beam through high-strength bolt rods; the steel column and the steel column foot are non-replaceable components; the double replaceable energy dissipation component comprises an energy dissipation steel plate and an energy dissipation steel rod; the energy dissipation steel plate dissipates the energy input into the structure as the first line of defense; when the energy dissipation steel plate generates plastic deformation, the energy dissipation steel rod is still in an elastic state, thereby serving as the second line of defense to increase the safety redundancy of the structure and improve the seismic performance of the structure. The yield displacement of the energy dissipation steel plate and the energy dissipation steel rod is different, thereby realizing stage-by-stage yield energy dissipation; under the action of different grade earthquakes, the damage can be concentrated on the replaceable energy dissipation component after the earthquake, the main structure is not damaged or slightly damaged, and the function of the overall structure can be quickly restored by replacing the damaged energy dissipation component.

Description

Technical Field

[0001] This invention belongs to the fields of architectural engineering and structural engineering, and specifically relates to a steel column base structure with dual replaceable energy-dissipating connections and its design method. Background Technology

[0002] Frequent earthquakes cause damage to buildings. With global economic development and rapid urbanization, and the continuous innovation of technology and concepts in the construction industry, the post-earthquake recoverability of building structures has gradually become a research hotspot. To address the problem of the difficulty in repairing building structures after earthquakes, scholars at home and abroad have proposed the concept of recoverable functional structures. Recoverable functional structures refer to structures that can restore their usability after an earthquake with little or no repair.

[0003] Currently, this is mainly achieved through three methods: replaceable structures, self-resetting structures, and swaying structures. Replaceable structures refer to concentrating damage to certain replaceable energy-dissipating components after an earthquake, thereby effectively controlling the structure's response and damage. After the earthquake, only the damaged energy-dissipating components need to be replaced to quickly restore the structure's function. Frame structures are one of the most widely used structural forms in buildings, and research on the post-earthquake functional recovery of frame structures is extensive. When frame structures encounter earthquakes, they satisfy the "strong column-weak beam" yielding mechanism. When plastic hinges appear at the beam-column joints, which act as the first line of seismic defense, the bending moment at the bottom of the bottom column is significantly greater than the bending moment at the top. Due to the larger bending moment distribution at the bottom column base, plastic hinges will inevitably appear there as well. Therefore, replaceable energy-dissipating components can be placed at the bottom column bases to control the damage to the bottom columns, thus achieving rapid functional recovery.

[0004] Currently, research on replaceable components for steel column bases by scholars at home and abroad mainly focuses on releasing displacement at the interface between the column base and the foundation, and setting up corresponding energy-dissipating components to dissipate energy and reduce vibration, thereby achieving functional recovery of the structure. However, the energy dissipation form is singular, and the failure of a single energy-dissipating component will lead to a significant reduction in the mechanical performance and seismic performance of the entire structure. Furthermore, since the interface between the column base and the foundation is used as the prying surface, the concrete surface of the foundation is easily crushed, causing damage to the concrete surface of the foundation, which is not conducive to the functional recovery of the structure after the earthquake, and has a significant impact on the seismic performance of the steel column. Summary of the Invention

[0005] To address the aforementioned deficiencies in existing technologies, the present invention aims to provide a steel column base structure with dual replaceable energy-dissipating connections and its design method. This structure protects the foundation and main structure by shifting the prying surface, preventing damage to the foundation surface concrete caused by the opening and closing of the steel column on the prying surface. By incorporating dual replaceable energy-dissipating components, the safety redundancy and seismic performance of the steel column are improved, preventing a significant reduction in the overall structural mechanical and seismic performance due to the failure of a single energy-dissipating component. Replacing the energy-dissipating component restores the structural function, achieving controllable and recoverable structural performance under seismic loading.

[0006] The present invention is achieved through the following technical solution.

[0007] According to one aspect of the present invention, a steel column base structure with dual replaceable energy-dissipating connection is provided, comprising a steel column, a steel column base, dual replaceable energy-dissipating components, and a ground beam; the steel column is connected to the steel column base via the dual replaceable energy-dissipating components, and the steel column base is connected to the ground beam via high-strength bolts.

[0008] The dual replaceable energy-consuming components include:

[0009] Energy-dissipating steel plates are used to connect the two sides of the bottom of the steel column and the connecting plate of the steel column foot platform. They move the prying surface from the top surface of the ground beam to the connecting plate of the steel column foot platform, preventing the opening and closing of the steel column on the prying surface from damaging the concrete surface of the foundation. The energy-dissipating steel plates preferentially dissipate the seismic energy input into the structure.

[0010] Energy-dissipating steel bars are used to connect steel columns and steel column bases. When the energy-dissipating steel plate undergoes plastic deformation, the energy-dissipating steel bars remain in an elastic state.

[0011] Preferably, the energy-consuming steel plate is an L-shaped plate, with a pad between the side of the energy-consuming steel plate and the steel column. The energy-consuming steel plate and the pad are connected to the steel column by high-strength bolts, and the bottom of the energy-consuming steel plate is connected to the platform connecting plate of the steel column foot by high-strength bolts.

[0012] Preferably, the steel column flange is connected to a buckling-resistance cover plate by high-strength bolts, and the buckling-resistance cover plate is not connected to the energy-consuming steel plate.

[0013] Preferably, a first transverse stiffening rib and a second transverse stiffening rib are provided at the upper and lower parts of the steel column, respectively. A support plate is provided above the second transverse stiffening rib, and a first short stiffening rib is provided below the support plate. A second short stiffening rib is provided between the second transverse stiffening rib and the bottom plate of the steel column.

[0014] As a preferred embodiment, the energy-consuming steel bar has threads at both ends. The energy-consuming steel bar passes through the reserved holes and is connected at one end to the support plate of the steel column through small pads and high-strength nuts at both ends, and at the other end to the platform connection plate of the steel column foot.

[0015] Preferably, the top of the steel column base is provided with a platform connecting plate, the side is welded with longitudinal stiffening ribs, the flange of the steel column base is welded with a boot beam, and the boot beam is welded with boot beam stiffening ribs.

[0016] Preferably, a support plate is provided below the platform connecting plate, and short stiffening ribs are provided between the support plate and the platform connecting plate.

[0017] Preferably, the height of the steel column base is higher than the height of the boot beam.

[0018] According to another aspect of the present invention, a design method for the aforementioned steel column base structure with dual replaceable energy-dissipating connections is provided, comprising:

[0019] The cross-sectional dimensions of the steel column and the structural parameters and material strength of the dual replaceable energy-dissipating components are determined based on the maximum bending moment and axial force that the steel column needs to resist.

[0020] To simulate the stress state under actual earthquake action, axial and horizontal forces are applied to the top of the steel column. Based on the state of the energy-dissipating steel plate on the tension side when it just yields after the steel column rotates by a certain angle, the resisting bending moment generated by the energy-dissipating steel plate and energy-dissipating steel bar on the prying point is obtained; then the axial tensile amount of the energy-dissipating steel bar and energy-dissipating steel plate after the steel column rotates by an angle is obtained.

[0021] Based on the axial tensile amount of the energy-consuming steel bar and the energy-consuming steel plate after the rotation angle of the steel column, the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar of the dual replaceable energy-consuming components is calculated.

[0022] Based on the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar, the displacement angle of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield is obtained.

[0023] Adjust the cross-sectional dimensions of the steel column and the structural parameters of the energy-consuming steel plate and steel bar based on the displacement angle when the energy-consuming steel plate and steel bar just reach yield.

[0024] Preferably, the displacement angles of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield strength are obtained, including:

[0025] (a) Apply axial and horizontal forces to the top of the steel column, and obtain the resisting bending moment of the energy-dissipating steel plate and the energy-dissipating steel bar on the prying point based on the state of the energy-dissipating steel plate just yielding when the steel column rotates by an angle θ.

[0026] (b) Then, the axial tensile amount of the energy-consuming steel bar after the steel column rotates by an angle and the axial compression amount of the energy-consuming steel plate after the steel column rotates by an angle are obtained.

[0027] (c) Based on the length of the energy-consuming steel plate section and the transition section, the axial tensile amount of the energy-consuming steel plate after the rotation angle of the steel column and the axial tensile amount of the energy-consuming steel bar after the rotation angle of the steel column, the yield strain of the energy-consuming steel plate and the energy-consuming steel bar when they reach the yield load under axial tensile force is obtained respectively, and the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar is obtained.

[0028] (d) Based on the initial elastic modulus of the energy-consuming steel plate and the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar, obtain the displacement angle of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield.

[0029] The present invention, by adopting the above technical solution, has the following beneficial effects:

[0030] This structure with dual replaceable energy-dissipating steel column bases avoids damage to the foundation surface concrete by moving the prying face upwards, thus protecting the foundation and main structure. The dual replaceable energy-dissipating components enhance the safety redundancy and seismic performance of the steel columns, addressing the issue of insufficient energy dissipation caused by the compressive buckling of the energy-dissipating steel plates. An additional cover plate constrains the out-of-plane buckling of the energy-dissipating steel plates, allowing them to fully utilize their material properties. Due to the different placement, material strength, and dimensions of the dual replaceable energy-dissipating components, the energy-dissipating steel plates yield before the energy-dissipating steel bars, enabling the structure to dissipate energy in stages under different levels of seismic loading. Furthermore, post-earthquake damage is concentrated on the replaceable energy-dissipating components, while the main structure remains undamaged or only slightly damaged. Replacing the energy-dissipating components allows for rapid restoration of the overall structure's function.

[0031] This structure has the following advantages:

[0032] 1. By moving the prying surface upwards, damage to the foundation surface concrete is avoided from being caused by the opening and closing of the prying surface, thus protecting the foundation and main structure.

[0033] 2. The problem of insufficient energy dissipation caused by the easy buckling of energy-consuming steel plates under pressure was solved by adding a cover plate to restrain the out-of-plane buckling of the energy-consuming steel plates so that they can give full play to the material function.

[0034] 3. The installation of dual replaceable energy dissipation components improves the safety redundancy and seismic performance of steel columns. The dual replaceable energy dissipation components consist of energy dissipation steel plates and energy dissipation steel bars. Due to the different arrangement positions, material strengths and component sizes of the dual replaceable energy dissipation components, the energy dissipation steel plates will yield before the energy dissipation steel bars, enabling the structure to dissipate energy in stages under different levels of seismic action.

[0035] 4. When the structure is subjected to earthquake, the plastic damage is concentrated in the dual replaceable energy-dissipating components, and the structural function can be quickly restored after the earthquake by replacing the damaged energy-dissipating components. Attached Figure Description

[0036] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, do not constitute an undue limitation of the invention. In the drawings:

[0037] Figure 1 This is a schematic diagram of the structure of the present invention;

[0038] Figure 2 This is a schematic diagram of the assembly structure of the various components of the present invention;

[0039] Figure 3 This is a schematic diagram of the deformation of the dual energy-dissipating component of the present invention under load.

[0040] Figure 4 This is a schematic diagram of the overall structural deformation of the present invention under load.

[0041] Figure 5 This is a schematic diagram of the numerical simulation of the present invention;

[0042] Figure 6 This is a diagram showing the effective stress of the structure when the horizontal displacement at the top of the column is loaded to its maximum.

[0043] Figures 7(a) and (b) show the effective stress diagram and equivalent plastic strain diagram of the energy-consuming steel plate when the column top displacement is loaded to 42.5 mm, respectively.

[0044] Figures 8(a) and (b) show the effective stress diagram and equivalent plastic strain diagram of the energy-dissipating steel bar when the column top displacement is loaded to 42.5 mm, respectively.

[0045] Figure 9 This is a comparison chart of the hysteresis curves of numerical simulations of an example of the present invention and a steel column base connected only by an energy-consuming steel plate.

[0046] In the diagram: 1. First transverse stiffening rib, 2. Steel column, 3. Support plate, 4. First short stiffening rib, 5. Pad plate, 6. Energy-dissipating steel plate, 7. First high-strength bolt, 8. Anti-buckling cover plate, 9. Energy-dissipating steel bar, 10. Second transverse stiffening rib, 11. Second short stiffening rib, 12. Platform connecting plate, 13. Steel column base, 14. Longitudinal stiffening rib, 15. Boot beam, 16. Boot beam stiffening rib, 17. Ground beam, 18. Second high-strength bolt rod. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0048] like Figure 1 , 2As shown, this embodiment of the invention provides a steel column base structure with dual replaceable energy-consuming connection. The structure includes a steel column 2, a steel column base 13, dual replaceable energy-consuming components, and a ground beam 17. The steel column 2 is connected to the steel column base 13 through the dual replaceable energy-consuming components, and the steel column base 13 is connected to the ground beam 17 through high-strength bolt rods 18.

[0049] The steel column 2 is provided with a first transverse stiffening rib 1 and a second transverse stiffening rib 10 at the upper and lower parts respectively. A support plate 3 is provided above the second transverse stiffening rib 10, a first short stiffening rib 4 is provided below the support plate 3, and a second short stiffening rib 11 is provided between the second transverse stiffening rib 10 and the bottom plate of the steel column 2.

[0050] In this embodiment, the first transverse stiffening rib 1, the second transverse stiffening rib 10, the support plate 3, the first short stiffening rib 4, and the second short stiffening rib 11 are welded to the steel column 2.

[0051] The steel column base 13 has longitudinal stiffening ribs 14 welded to its side, and a boot beam 15 welded to its flange, with boot beam stiffening ribs 16 welded to the boot beam. The top of the steel column base 13 is a platform connecting plate 12, and a support plate 3 is provided below the platform connecting plate 12. A first short stiffening rib 4 is provided between the support plate 3 and the platform connecting plate 12.

[0052] The function of the support plate 3 is to ensure the force transmission of the energy-dissipating steel bar 9. When ensuring that the energy-dissipating steel bar 9 reaches its ultimate bearing capacity, the support plate 3 must still maintain an elastic state. The thickness is determined based on the maximum bending moment it experiences, using a simplified calculation of a three-sided support plate.

[0053] In this embodiment, the steel column base 13 is connected to a platform connecting plate 12, a support plate 3, a first short stiffening rib 4, a boot beam stiffening rib 16, a longitudinal stiffening rib 14, and a boot beam 15 via welding. The height of the steel column base 13 is approximately 0.2m higher than the height of the boot beam 15, which facilitates the subsequent replacement of the energy-consuming steel bars. The height of the boot beam is determined according to the weld length required for force transmission.

[0054] The dual replaceable energy-consuming components include an energy-consuming steel plate 6 and an energy-consuming steel bar 9.

[0055] The energy-dissipating steel plate 6 is an L-shaped plate. A pad 5 is placed between the energy-dissipating steel plate 6 and the steel column 2. The function of the pad 5 is to leave a gap so that the steel column 2 can rotate. In this embodiment, its thickness should preferably be 10mm. The side of the energy-dissipating steel plate 6, the pad 4, and the anti-buckling cover plate 8 are connected to the steel column 2 by the first high-strength bolt 7. The bottom of the energy-dissipating steel plate 6 is connected to the platform connecting plate 12 of the steel column foot 13 by the first high-strength bolt 7.

[0056] A buckling-resistance cover plate is connected to the flange of the steel column 2 by high-strength bolts, and the buckling-resistance cover plate is not connected to the energy-consuming steel plate.

[0057] The energy-dissipating steel bar 9 has threads at both ends. Passing through pre-drilled holes, the bar is connected at one end to the support plate 3 of the steel column 2 frame via small end pads and high-strength nuts, and at the other end to the platform connecting plate 12 of the steel column base 13. The platform connecting plate 12 serves as a load-bearing platform; in this embodiment, its thickness is preferably 30mm to ensure bending stiffness and strength.

[0058] The steel column 2 is placed on the platform connecting plate 12. The steel column 2, energy-consuming steel plate 6, energy-consuming steel bar 9 and steel column foot 13 are connected into a whole by high-strength bolts 7, and then connected to the ground beam 17 by high-strength bolt rod 18 to form the whole structure.

[0059] Both welded connections and high-strength bolt connections are rigid connections. When the structure is subjected to seismic forces, the prying surface of steel column 2 occurs at platform connecting plate 12, which prevents the prying of the steel column from occurring on the foundation surface and prevents the opening and closing of the steel column on the prying surface from damaging the foundation surface concrete.

[0060] Steel column 2, steel column base 13 and ground beam 18 are all made of Q355 steel, and energy-consuming steel plate 6 and energy-consuming steel bar 9, which are double replaceable energy-consuming components, are made of Q235 or LY225 steel.

[0061] The energy-dissipating steel plate is moved from the top surface of the ground beam to the connecting plate of the steel column base platform. This changes the position of the prying surface, protecting the foundation and main structure and preventing damage to the foundation surface concrete caused by the opening and closing of the steel column on the prying surface. As a connecting component, the energy-dissipating steel plate transfers the force on the steel column to the steel column base. During an earthquake, it is prone to stress concentration and plastic deformation, serving as the first line of defense against earthquakes to dissipate the energy input into the structure.

[0062] Energy-dissipating steel bars are used to connect steel columns to steel column bases. When subjected to a certain seismic force, the energy-dissipating steel plates will undergo plastic deformation, while the energy-dissipating steel bars remain in an elastic state. Therefore, energy-dissipating steel bars can serve as a second line of defense to increase the safety redundancy of the structure and improve its seismic performance.

[0063] In this embodiment, based on the arrangement of the dual replaceable energy dissipation components, material strength, and component size, the energy dissipation steel plate can be designed to yield before the energy dissipation steel bar. Under small to medium earthquakes, the energy dissipation steel plate undergoes plastic deformation first, while the energy dissipation steel bar remains in an elastic state, thus improving the structural safety reserve. Under large earthquakes, both the energy dissipation steel plate and the energy dissipation steel bar undergo plastic deformation, jointly dissipating earthquake energy.

[0064] When subjected to earthquake forces, the structure dissipates seismic energy through the plastic deformation of energy-dissipating steel plates and bars, protecting the main structure from damage or causing only minor damage. After the earthquake, the structure's function can be restored by replacing the energy-dissipating components, thus achieving controllable and recoverable structural performance under earthquake conditions.

[0065] The structure of this invention can be applied to the bottom steel columns of steel frame structures to achieve energy dissipation and vibration reduction, and restore the structural function of the steel frame structure.

[0066] This invention further provides a design method for a steel column base structure with dual replaceable energy-dissipating connections, comprising the following steps:

[0067] Step 1: Determine the cross-sectional dimensions of the steel column and the structural parameters and material strength of the dual replaceable energy-consuming components based on the maximum bending moment M and axial force N that the steel column needs to resist. The cross-sectional dimensions of the steel column can be determined by the following formula.

[0068]

[0069]

[0070] In the formula, A represents the cross-sectional dimension of the steel column, N represents the axial compressive force on the steel column, and M represents the maximum bending moment that the steel column needs to resist. W represents the stability coefficient of an axially compressed member within the plane of bending moment action. 1x r represents the gross section modulus of the fiber under maximum compression in the plane of bending moment. x β represents the coefficient of plastic development of the cross section. mx λ represents the equivalent bending moment coefficient, f represents the design value of the steel grade used for the steel column, and λ represents the equivalent bending moment coefficient. x The slenderness ratio of the steel column is represented by E, and the elastic modulus of the steel used in the column is represented by E.

[0071] Step 2: Simulate the stress state under actual earthquake action. Apply axial and horizontal forces to the top of the steel column. Based on the state of the energy-dissipating steel plate on the tension side when it just yields after the steel column rotates by a certain angle, obtain the resisting bending moment generated by the energy-dissipating steel plate and energy-dissipating steel bar on the prying point; and then obtain the axial tensile amount of the energy-dissipating steel bar and energy-dissipating steel plate after the steel column rotates by an angle.

[0072] Based on the axial tensile amount of the energy-consuming steel bar and the energy-consuming steel plate after the rotation angle of the steel column, the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar of the dual replaceable energy-consuming components is calculated.

[0073] Based on the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar, the displacement angle when the energy-consuming steel plate and the energy-consuming steel bar just reach the yield is obtained.

[0074] Specifically:

[0075] (a) Apply axial and horizontal forces to the top of the steel column to obtain the state of the energy-dissipating steel plate on the tension side when it just yields, based on the rotation angle θ of the steel column. Obtain the resisting bending moment M generated by the energy-dissipating steel plate and the energy-dissipating steel bar on the prying point. P M b ;

[0076] M P =FP1 Δ P1 +F P2 Δ P2 =F P1 (D+t)cosθ+F P2 tcosθ=(t(F P1 +F P2 )+F P1 D)cosθ

[0077]

[0078] In the formula, F P1 F represents the yield load of the energy-dissipating steel plate p1 on the tension side. P2 F represents the load on the compressive energy-dissipating steel plate p2 when the tension-side energy-dissipating steel plate p1 yields. b Δ represents the load on energy-dissipating steel plate b when energy-dissipating steel plate p1 on the tension side yields. p1 Δ represents the lever arm of the energy-dissipating steel plate p1 on the tension side, after the steel column rotates by θ, at the distance from the prying point. p2 Δ represents the lever arm of the energy-dissipating steel plate p2 on the compression side from the prying point after the steel column rotates. b Let θ represent the lever arm of the energy-consuming steel bar b at the prying point after the steel column rotates by θ, D be the height of the steel column section, and t be the thickness of the pad.

[0079] (b) Then, the axial tensile amount ΔL of the energy-consuming steel bar after the steel column rotates by an angle θ is obtained. p1 The axial compression ΔL of the energy-consuming steel plate after the steel column rotates by an angle θ p2 :

[0080] ΔL p1 =Δl1cosα1=(D+t)θ

[0081]

[0082] ΔL p2 =Δl3cosα3=tθ

[0083] In the formula, ΔL b The value represents the axial tensile amount of the energy-consuming steel bar after the steel column rotates by an angle θ. D is the height of the steel column section, t is the thickness of the pad, Δl1, Δl2, and Δl3 represent the displacement changes of the top of the tension-side energy-consuming steel plate, the compression-side energy-consuming steel plate, and the energy-consuming steel bar before and after the rotation angle, respectively. α1, α2, and α3 represent the angles between the displacement changes of the top of the tension-side energy-consuming steel plate, the compression-side energy-consuming steel plate, and the energy-consuming steel bar before and after the rotation angle and the axial tensile amount, respectively.

[0084] (c) Based on the length L of the energy-consuming steel plate energy-consuming section and transition section p The axial tensile amount ΔL of the energy-consuming steel plate p1 after the steel column rotates by an angle θ p1The axial tensile amount ΔL of the energy-consuming steel bar after the steel column rotates by an angle θ b The yield strains of the energy-consuming steel plate and the energy-consuming steel bar b when subjected to axial tensile force and reaching the yield load were obtained respectively. and This yields the elastic yield load of the energy-dissipating steel plate and the energy-dissipating steel bar. and

[0085]

[0086]

[0087] In the formula, Let A represent the initial elastic modulus of the energy-consuming steel plate and the energy-consuming steel bar, respectively. p1 A b These represent the cross-sectional areas of the energy-consuming sections of the energy-consuming steel plate and the energy-consuming steel bar, respectively, which are subjected to force. These represent the yield stresses of the energy-consuming steel plate and the energy-consuming steel bar when they just reach their yield point, respectively.

[0088] (d) Based on the initial elastic modulus of the energy-consuming steel plate p1 and the energy-consuming steel bar b Elastic yield load of energy-dissipating steel plates and bars and The displacement angles of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield were obtained. and

[0089]

[0090]

[0091] Deformation of the dual energy-dissipating component under load is shown below. Figure 3 As shown, the overall structural deformation under load is shown in the figure. Figure 4 As shown.

[0092] Step 3: Adjust the cross-sectional dimensions of the steel column and the structural parameters of the energy-consuming steel plate and the energy-consuming steel bar according to the displacement angle when the energy-consuming steel plate and the energy-consuming steel bar just reach the yield point.

[0093] The effects of the present invention will be further explained below with reference to the accompanying drawings.

[0094] To verify the effectiveness of this invention, the structure proposed in this invention was designed using the stress conditions of a bottom-level steel column in an actual engineering project. The steel column was made of Q355 steel with dimensions of HW300×300×10×16 (mm). The column base was also made of Q355 steel with dimensions of HW350×350×12×20mm (mm). The platform connection plate thickness was 30mm. Both the energy-dissipating steel plate and energy-dissipating steel rod were made of Q235 steel. The energy-dissipating section of the energy-dissipating steel plate was 50mm wide and 8mm thick, and the energy-dissipating steel rod had a diameter of 20mm. The seismic performance of the structure was numerically analyzed using the finite element simulation software ABAQUS. The constitutive data of the steel used were taken from tensile tests of actual steel by other researchers. To simplify the calculation, the ground beam was removed from the modeling analysis because its high stiffness means it will not deform and will not affect the mechanical performance of the superstructure.

[0095] like Figure 5 As shown, the numerical model is established using ABAQUS. The weld connection is simplified to the binding between components. The contact relationship between the components is consistent with reality. The tangential friction coefficient between steel is taken as 0.3. A vertical axial force with an axial compression ratio of 0.3 is applied to control the displacement of the steel column apex and cyclically load the structure.

[0096] like Figure 6 As shown in the figure, when the column top displacement is loaded to 42.5mm, the effective stress distribution of the entire structure is shown. It can be seen from the figure that the prying surface occurs at the expected position. Due to the vertical axial force and cyclic reciprocating load, the stress of each component at the prying point is relatively large overall. The force transmission path is as expected. Since the connection between the steel column and the steel column base is connected by double replaceable energy-dissipating components, the stress is more concentrated on the energy-dissipating components.

[0097] As shown in Figures 7(a) and (b), when the column top displacement is loaded to 42.5 mm, the effective stress diagram of the energy-dissipating steel plate shows that the effective stress distribution on the plate is relatively uniform, with the stress value in the energy-dissipating section being greater than that in other parts, indicating that the stress is concentrated in the energy-dissipating section of the steel plate. Furthermore, the stress values ​​all exceed the yield stress of the steel plate, indicating that the restraint cover plate has fully played its role in preventing out-of-plane buckling of the energy-dissipating steel plate and fully utilizing the material's properties. The equivalent plastic strain diagram of the energy-dissipating steel plate shows a significant accumulation of plastic strain, indicating that the energy-dissipating steel plate underwent plastic deformation during structural loading, dissipating the energy input to the structure.

[0098] As shown in Figures 8(a) and (b), when the column top displacement is loaded to 42.5 mm, the effective stress distribution on the energy-dissipating steel plate is very uniform, and the stress value of the energy-dissipating steel rod is much lower than that of the energy-dissipating steel plate. This indicates that the energy-dissipating steel rod can yield to the energy-dissipating steel plate and play the role of a second line of defense, thereby improving the safety redundancy and seismic performance of the entire structure. The equivalent plastic strain diagram of the energy-dissipating steel rod shows that the energy-dissipating steel rod has undergone a certain degree of plastic deformation.

[0099] Figure 9 The diagram shows a comparison of the hysteresis curves of an example of this invention and a steel column base structure connected only by an energy-dissipating steel plate. Before a displacement angle of 11.39 mm (0.67% displacement angle), the present invention is in the elastic stage, with the hysteresis curve tending towards a straight line and good reset effect. After a displacement of 11.39 mm (0.67% displacement angle), the present invention enters the reset and energy dissipation stage, with the slope of the diagonal of the hysteresis curve gradually decreasing, stiffness decreasing, and the hysteresis loop area gradually increasing. The hysteresis curve of the present invention exhibits a typical "double flag" shape, possessing good energy dissipation and self-reset capabilities, with virtually no residual deformation, and its ultimate bearing capacity is higher than that of a steel column base structure connected only by an energy-dissipating steel plate, indicating a high safety margin. When the load reaches 42.5 mm, the plastic damage of the present invention is concentrated on the energy-dissipating steel plate and energy-dissipating steel bar, while other structures remain in an elastic state. Therefore, the structural function can be quickly restored by replacing the damaged energy-dissipating components, achieving the expected effect of the present invention.

[0100] This invention is not limited to the above embodiments. Based on the technical solutions disclosed in this invention, those skilled in the art can make some substitutions and modifications to some of the technical features without creative effort, and all such substitutions and modifications are within the protection scope of this invention.

Claims

1. A design method of a steel column base structure with double replaceable energy dissipation connection, characterized in that, The method employs a steel column base structure with dual replaceable energy-dissipating connections, which includes a steel column, steel column base, dual replaceable energy-dissipating components, and a ground beam. The steel columns are connected to the steel column bases via dual replaceable energy-consuming components, and the steel column bases are connected to the ground beams via high-strength bolts. The dual replaceable energy-consuming components include: Energy-dissipating steel plates are used to connect the two sides of the bottom of the steel column and the connecting plate of the steel column foot platform. They move the prying surface from the top surface of the ground beam to the connecting plate of the steel column foot platform, preventing the opening and closing of the steel column on the prying surface from damaging the concrete surface of the foundation. The energy-dissipating steel plates preferentially dissipate the seismic energy input into the structure. Energy-dissipating steel bars are used to connect steel columns and steel column bases. When the energy-dissipating steel plate undergoes plastic deformation, the energy-dissipating steel bars remain in an elastic state. The method includes: The cross-sectional dimensions of the steel column and the structural parameters and material strength of the dual replaceable energy-dissipating components are determined based on the maximum bending moment and axial force that the steel column needs to resist. To simulate the stress state under actual earthquake action, axial and horizontal forces are applied to the top of the steel column. Based on the state of the energy-dissipating steel plate on the tension side when it just yields after the steel column rotates by a certain angle, the resisting bending moment generated by the energy-dissipating steel plate and energy-dissipating steel bar on the prying point is obtained; then the axial tensile amount of the energy-dissipating steel bar and energy-dissipating steel plate after the steel column rotates by an angle is obtained. Based on the axial tensile amount of the energy-consuming steel bar and the energy-consuming steel plate after the rotation angle of the steel column, the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar of the dual replaceable energy-consuming components is calculated. Based on the elastic yield load of the energy-consuming steel plate and the energy-consuming steel bar, the displacement angle of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield is obtained. Adjust the cross-sectional dimensions of the steel column and the structural parameters of the energy-consuming steel plate and steel bar based on the displacement angle when the energy-consuming steel plate and steel bar just reach yield.

2. The design method for the steel column base structure with dual replaceable energy-dissipating connections according to claim 1, characterized in that, The displacement angles of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield strength are obtained, including: (a) Apply axial and horizontal forces to the top of the steel column, and adjust the force according to the rotation of the steel column. The state of the energy-dissipating steel plate on the tension side at which it just yields is obtained, and the resisting bending moment generated by the energy-dissipating steel plate and the energy-dissipating steel bar at the prying point is obtained. , ; In the formula, Indicates the energy-dissipating steel plate on the tension side The yield load, Indicates the energy-dissipating steel plate on the tension side Energy-dissipating steel plate on the compression side during yielding The load, Indicates the energy-dissipating steel plate on the tension side Energy-consuming steel plate at yield The load, Indicates the energy-dissipating steel plate on the tension side As the steel column rotates The lever arm at the rear distance from the prying point Indicates the energy-dissipating steel plate on the pressure side The lever arm at the distance from the prying point after the steel column rotates Indicates energy-consuming steel bars As the steel column rotates The lever arm at the rear distance from the prying point The height of the steel column section. The thickness of the pad; (b) This leads to the energy-consuming steel bar rotating in the steel column. Axial stretch after angle And the energy-consuming steel plate rotates in the steel column Axial compression after angle : In the formula, This indicates that the energy-consuming steel bar rotates in the steel column. Axial stretching after the angle The height of the steel column section. The thickness of the pad, , , These represent the changes in displacement of the top of the tension-side energy-dissipating steel plate, the compression-side energy-dissipating steel plate, and the energy-dissipating steel bar before and after the rotation angle, respectively. , , These represent the angles between the changes in the top displacement of the tension-side energy-consuming steel plate, the compression-side energy-consuming steel plate, and the energy-consuming steel bar before and after the rotation angle, and the axial tensile amount, respectively. (c) Based on the length of the energy-consuming steel plate energy-consuming section and the transition section Energy-consuming steel plates As the steel column rotates Axial stretch after angle And the energy-consuming steel bar rotates in the steel column Axial stretch after angle Energy-consuming steel plates and energy-consuming steel bars were obtained respectively. Yield strain at yield load under axial tensile force and Thus, the elastic yield loads of the energy-dissipating steel plates and bars are obtained. and ; In the formula, , These represent the initial elastic moduli of the energy-consuming steel plate and the energy-consuming steel bar, respectively. , These represent the cross-sectional areas of the energy-consuming sections of the energy-consuming steel plate and the energy-consuming steel bar, respectively, which are subjected to force. , These represent the yield stresses of the energy-consuming steel plate and the energy-consuming steel bar when they just reach their yield point, respectively. (d) Based on energy-consuming steel plates and energy-consuming steel bars b initial elastic modulus , Elastic yield load of energy-consuming steel plates and energy-consuming steel bars and The displacement angles of the energy-consuming steel plate and the energy-consuming steel bar when they just reach yield were obtained. and ; 。 3. A steel column base structure with dual replaceable energy-dissipating connections as described in claim 1, characterized in that, Includes steel columns, steel column bases, dual replaceable energy-consuming components, and ground beams; The steel columns are connected to the steel column bases via dual replaceable energy-consuming components, and the steel column bases are connected to the ground beams via high-strength bolts. The dual replaceable energy-consuming components include: Energy-consuming steel plates are used to connect the two sides of the bottom of the steel column and the connecting plate of the steel column foot platform. Energy-consuming steel bars are used to connect steel columns to steel column bases; The top of the steel column base is provided with a platform connecting plate, and longitudinal stiffening ribs are welded to the side. Boot beams are welded to the flanges of the steel column base, and boot beam stiffening ribs are welded to the boot beams.

4. The steel column base structure with dual replaceable energy-consuming connections according to claim 3, characterized in that, The energy-consuming steel plate is an L-shaped plate. A pad is placed between the side of the energy-consuming steel plate and the steel column. The energy-consuming steel plate and the pad are connected to the steel column by high-strength bolts. The bottom of the energy-consuming steel plate is connected to the platform connecting plate of the steel column foot by high-strength bolts.

5. The steel column base structure with dual replaceable energy-dissipating connections according to claim 4, characterized in that, The steel column flange is connected to a buckling-resistance cover plate, and the buckling-resistance cover plate is not connected to the energy-dissipating steel plate.

6. The steel column base structure with dual replaceable energy-consuming connections according to claim 3, characterized in that, The upper and lower parts of the steel column are respectively provided with a first transverse stiffening rib and a second transverse stiffening rib. A support plate is provided above the second transverse stiffening rib, and a first short stiffening rib is provided below the support plate. A second short stiffening rib is provided between the second transverse stiffening rib and the bottom plate of the steel column.

7. The steel column base structure with dual replaceable energy-consuming connections according to claim 6, characterized in that, The energy-consuming steel bar has threads at both ends. The energy-consuming steel bar passes through the reserved holes and is connected to the support plate of the steel column at one end through the small pads and high-strength nuts at both ends. The other end is connected to the platform connection plate of the steel column foot.

8. The steel column base structure with dual replaceable energy-consuming connections according to claim 3, characterized in that, A support plate is provided below the platform connecting plate, and short stiffening ribs are provided between the support plate and the platform connecting plate.

9. The steel column base structure with dual replaceable energy-consuming connections according to claim 3, characterized in that, The height of the steel column base is higher than the height of the boot beam.

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