A hierarchical yielding energy dissipation connection device and a design method thereof

Abstract

The application relates to a hierarchical yielding energy dissipation connecting device and a design method thereof, and the hierarchical yielding energy dissipation connecting device comprises a fixed support, an upper beam, a lower beam, two steel columns and a hierarchical yielding energy dissipation device; the hierarchical yielding energy dissipation device comprises an X-shaped bending energy dissipation plate and a ring-shaped energy dissipation piece; the ring-shaped energy dissipation piece comprises two groups of circular-end energy dissipation segments arranged oppositely; each circular-end energy dissipation segment comprises a circular arc segment and a straight segment; an end plate is arranged outside the straight segment, and the straight segment and the end plate are connected through high-strength bolts; the X-shaped bending energy dissipation plate is connected to the inner sides of the two straight segments respectively, and the plate width of the X-shaped bending energy dissipation plate linearly changes from the middle to the two ends; under the action of small earthquakes, the X-shaped bending energy dissipation plate generates plastic deformation through out-of-plane bending to dissipate energy; under the action of medium earthquakes, the circular-end energy dissipation segments generate plastic deformation through the up-down mutual movement of the two side end plates to dissipate energy; under the action of large earthquakes, the X-shaped bending energy dissipation plate and the ring-shaped energy dissipation piece jointly yield into plastic energy dissipation.

Description

Technical Field

[0001] This invention relates to the field of structural energy dissipation and vibration reduction technology, specifically to a graded yielding energy dissipation connection device and its design method. Background Technology

[0002] With the increasing demands for seismic resistance in building structures, traditional metal dampers, due to their single energy dissipation and limited yield point, cannot respond in stages to different earthquake intensities, thus limiting their practical engineering applications. For example, traditional metal dampers have a large yield load and enter plastic yielding for energy dissipation under strong earthquakes, while their energy dissipation and vibration reduction effects are not significant under frequent minor and moderate earthquakes. To enable metal dampers to have multiple lines of defense, more effectively cope with earthquakes of various magnitudes, and achieve graded energy dissipation under different seismic loads, thus meeting performance design goals, many related dampers with multiple yield points have been developed in recent years.

[0003] The single energy dissipation method is a problem that needs to be addressed in the design of traditional energy-dissipating dampers. Because the yield displacement cannot be flexibly designed, the energy dissipation capacity of the damper is unstable under both low-intensity and strong earthquakes. In existing graded yield energy dissipators, the design is complex and the application range is narrow, and the graded yield displacement is not obvious enough, making them unsuitable for frame damping, and corresponding design methods are lacking.

[0004] How to provide a graded yield energy dissipator that can dissipate energy in stages under earthquakes of different intensities and has superior performance, and propose corresponding seismic design methods, has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] To address the problems existing in the prior art, the purpose of this invention is to provide a graded yield energy dissipation connection device and its design method, which can realize staged energy dissipation under different seismic actions, and has good hysteresis performance. Plastic damage is concentrated on the energy dissipation component, effectively avoiding damage to the main support.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A graded yield energy dissipation connection device includes a fixed support, an upper beam, a lower beam, two steel columns, and a graded yield energy dissipation device.

[0008] The graded yield energy dissipation device includes an X-shaped bending energy dissipation plate and an annular energy dissipation component;

[0009] The annular energy-consuming component includes two sets of round-end energy-consuming sections arranged opposite to each other. The two sets of round-end energy-consuming sections are connected by a V-shaped butt weld. Each round-end energy-consuming section includes an arc segment and a straight segment. The width of the straight segment is greater than the width of the arc segment.

[0010] There is a short transition area between the arc segment and the straight segment, which is smoothly connected by rounded corners;

[0011] The two straight sections are each equipped with an end plate on their outer side, and the straight sections are connected to the end plates by high-strength bolts.

[0012] The end plate and the node plate are perpendicular and fixed by welding. The node plate is used to connect to four externally inclined X-shaped supports to form an X-shaped support frame with a graded yielding energy dissipation connection device.

[0013] The X-shaped bending energy dissipation plate is connected to the inner sides of two straight sections at both ends. Its width changes linearly from narrow in the middle to wide at both ends, and is proportional to the bending moment distributed along the length of the plate.

[0014] Two steel columns are spaced apart on fixed supports. The upper beam and lower beam are horizontally connected to the two steel columns respectively. The upper beam is located above the lower beam. The ends of the four supports are connected to the intersections of the upper beam, lower beam and the two steel columns respectively.

[0015] When the X-shaped support frame undergoes horizontal lateral displacement under seismic loading, the axial forces generated by the horizontal loads of the four supports converge at the energy-dissipating connection, balancing the horizontal forces in the horizontal direction. The shear force in the vertical direction acts on the graded yielding energy-dissipating device. Under minor earthquakes, the X-shaped bending energy-dissipating plate dissipates energy through out-of-plane bending and plastic deformation, and can be used after the earthquake without replacement. Under moderate earthquakes, the annular energy-dissipating component undergoes plastic deformation of the arc segment through the vertical displacement of the end plate, dissipating energy together with the X-shaped bending energy-dissipating plate, and can be used after the earthquake without replacement. Under major earthquakes, the X-shaped bending energy-dissipating plate and the annular energy-dissipating component yield together and enter into plastic energy dissipation. If the residual inter-story drift angle of the overall structure after a major earthquake is less than 0.5%, it can be easily and efficiently inspected and replaced, ensuring that the seismic performance of the structure is restored to the design level after repair.

[0016] Furthermore, the outer center of the end plate is vertically welded to the side of the node plate, and the four supports are welded to the two node plates in an X-shape.

[0017] The design method for a graded yield energy dissipation connection device includes the following steps:

[0018] Step 1: Determine the performance targets and seismic requirements of the ordinary cross-braced frame structure. Based on the seismic fortification intensity, fortification category and expected structural performance level of the building structure's location, determine the response of the ordinary braced frame structure under minor, moderate and major earthquakes, including the inter-story drift angle limit, base shear force and top displacement under each level of earthquake.

[0019] Step 2: Calculate the vertical force of the ordinary cross-braced frame system. Based on the seismic requirements and target performance indicators determined in Step 1, calculate the axial force generated by the X-shaped support frame under various levels of seismic action, and then determine the vertical shear force component acting on the energy dissipation device with the energy dissipation connection support frame.

[0020] Step 3: Design the parameters of each level of energy dissipation element based on the concept of graded yielding. According to the vertical shear force requirement obtained in Step 2, determine the range of variation of yield load and stiffness of X-shaped bending energy dissipation plate and ring energy dissipation element respectively, according to the graded yielding sequence of X-shaped bending energy dissipation plate yielding and energy dissipation under minor earthquake, ring energy dissipation element yielding and participating in energy dissipation under moderate earthquake, and graded yielding energy dissipation device jointly dissipating energy under major earthquake.

[0021] Step 4: Determine the stiffness ratio and strength ratio of the graded yield energy dissipation device to ensure the realization of the graded yielding sequence and that the structure has good energy dissipation efficiency, and reasonably control the stiffness and strength ratio relationship between the graded yield energy dissipation device and the main support system.

[0022] Step 5: Determine the dimensions of the X-shaped bending energy dissipation plate and the ring-shaped energy dissipation component. Based on the yield load determined in Step 3 and the stiffness ratio and strength ratio determined in Step 4, design the size range of the X-shaped bending energy dissipation plate and the ring-shaped energy dissipation component.

[0023] Step 6: Based on the performance verification results, clarify the construction measures and connection details;

[0024] Ensure that the connection of the X-shaped bending energy dissipation plate meets the following requirements: the connection between the two ends of the X-shaped bending energy dissipation plate and the straight section of the annular energy dissipation component adopts a full penetration groove weld; the strength design of the weld should follow the principle of equal strength or strong connection and weak component, that is, the bearing capacity of the weld is not lower than the yield bearing capacity of the base material, to ensure that the plastic hinge develops fully on the energy dissipation plate, rather than failing prematurely at the weld.

[0025] The plastic zone structure of the annular energy-consuming component should meet the following requirements: the connection between the arc segment and the straight segment of the annular energy-consuming component should be a smooth arc transition, and the inner radius R of the arc should not be less than twice the thickness of the plate, so as to reduce stress concentration and guide the plastic deformation to be evenly distributed throughout the arc segment; in the expected plastic deformation area of ​​the arc segment, the surface of the plate should be flat and free from defects such as cracks and delamination that affect the plastic development.

[0026] Furthermore, the vertical shear force of the support The calculation formula is obtained from the decomposition of the supporting axial force: ,in, For the axial force of a single support, To determine the angle between the support and the horizontal plane, it is necessary to calculate the axial force of the support under both the elastic yield state and the ultimate state. and Thus, the corresponding vertical shear force components are obtained. and .

[0027] Furthermore, under minor earthquakes: the design yield load of the X-shaped bending energy dissipation plate. It should meet the following requirements: ,in, This corresponds to the vertical shear force generated when the support reaches elastic yield under minor earthquake conditions. The safety factor for the X-shaped bending energy dissipation plate is to ensure that the X-shaped bending energy dissipation plate can preferentially enter the plastic state under minor earthquakes;

[0028] Design yield load of ring-shaped energy dissipation component under moderate earthquake action: It should meet the following requirements: ,in, This corresponds to the vertical shear force of the support under moderate earthquake conditions. The safety factor for the ring-shaped energy-consuming component must be guaranteed. This causes the annular energy-dissipating component to begin to yield significantly only during moderate earthquakes;

[0029] Under strong earthquake conditions: Under strong earthquake conditions, both the X-shaped bending energy dissipation plate and the annular energy dissipation component enter the plastic state and work together. The combined ultimate bearing capacity of the two is... ,in, This refers to the vertical shear force when the support reaches its ultimate state under a major earthquake. The overall safety factor ensures the safety margin of the structure under major earthquakes.

[0030] Furthermore, based on the graded yield load determined in step 3, the stiffness ratio and strength ratio of the X-shaped bending energy dissipation plate and the annular energy dissipation component in the graded yield energy dissipation device are reasonably selected as follows, in order to achieve the best balance between controlling the structural response and optimizing energy dissipation efficiency.

[0031] First stiffness ratio: Initial bending stiffness of the X-shaped bending energy dissipation plate Equivalent vertical stiffness of the support system at the nodes The ratio is controlled as follows: ;

[0032] Second stiffness ratio: Initial stiffness of the ring-shaped energy dissipation component Equivalent vertical stiffness of the support system at the nodes The ratio is controlled as follows: ;

[0033] First strength ratio: Yield load of X-shaped bending energy dissipation plate Vertical shear force component at support yielding The ratio is controlled as follows: ;

[0034] Second strength ratio: Yield load of the ring-shaped energy-dissipating component Vertical shear force component at support yielding The ratio should be controlled as follows: ;

[0035] Based on the yield load of the X-shaped bending energy dissipation plate Based on the preset plate thickness and material yield strength, the specific variation dimensions are determined through calculation, so that the actual stress condition of the plate matches the ideal design model;

[0036] Based on the yield load of the ring-shaped energy dissipation component Determine the radius, cross-sectional dimensions, and length of the straight section of the arc segment; adjust them to ensure that the actual parameters of each component meet the requirements of steps 3 and 4.

[0037] Furthermore, for X-shaped bending energy-dissipating plates with out-of-plane yield energy dissipation, the calculation of their yield load and yield moment is clarified, and the geometric dimensions of the steel plate used to manufacture the X-shaped bending energy-dissipating plate are reasonably determined; generally, the height-to-thickness ratio is greater than 10, and the influence of shear stress can be ignored. According to the stress calculation formula for bending, the stress at the cross-section of the steel plate is solved as follows: (1);

[0038] For height The bending moment at the section; To calculate the distance from the point to the neutral axis of the cross section; For height Moment of inertia about the neutral axis;

[0039] The bending moments at the top and bottom ends of the plate are as follows: With the same direction, the steel plate can be adjusted to any height. Bending moment at:

[0040] (2);

[0041] but The moment of inertia of the directional section is (3);

[0042] The width of the steel plate. For the thickness of the steel plate, This refers to the height of the steel plate.

[0043] Substituting formulas (2) to (3) into formula (1) yields the result for any height. The bending stress at the point is: (4);

[0044] For a specific damper, at a certain moment, only the above formula has the following expression. The variable indicates that the stress magnitude at all points of the same thickness at the same moment is the same, thus proving that all points of the same thickness will reach yield simultaneously. The formula for calculating the yield moment is: (5);

[0045] in , The yield stress;

[0046] Substituting formula (3) into formula (5), we can obtain the yield moment as: (6);

[0047] The maximum bending moment is when At that time, the yield moment is: (7);

[0048] At this point, the yield load of the energy dissipation panel is: (8);

[0049] To prevent shear failure of the X-shaped bending energy dissipation plate at the neck (where the width is smallest), its shear stress needs to be calculated; at the middle height of the X-shaped bending energy dissipation plate... Set minimum width at [location] The shear force at that section is (Considering a plasticity development coefficient of 1.5), the maximum shear stress is: (9);

[0050] in Let be the neck cross-sectional area; according to the Von-Mises yield criterion, the shear strength of the steel is . (10);

[0051] To prevent shearing damage to the neck, the following must be met: (11); The minimum width of the neck can be obtained. Construction requirements: (12); At the same time neck height Determined by geometric relations: (13);

[0052] Using the above formulas, the geometric dimensions of the X-shaped bending energy-dissipating plate can be reasonably determined, under the premise of ensuring that bending yielding precedes shear failure, so as to achieve the expected graded yielding and high-efficiency energy dissipation goals.

[0053] Furthermore, the restoring force model of the X-shaped bending energy dissipation plate is an ideal elastoplastic model, and its yield load... Initial stiffness and yield displacement The calculation formula is

[0054] ;

[0055] ;

[0056] ;

[0057] In the formula, This refers to the normal stress on the surface of the steel. The width of the steel plate; The thickness of the steel plate; This refers to the height of the steel plate. This refers to the number of X-shaped bending energy-dissipating panels; This refers to the elastic modulus of steel.

[0058] Furthermore, the restoring force model of the annular energy dissipation component is an ideal elastoplastic model, and its yield load... Initial stiffness and yield displacement The calculation formula is

[0059] ;

[0060] ;

[0061] ;

[0062] In the formula, This refers to the normal stress on the surface of the steel. The width of the round-ended energy-consuming section; The thickness of the steel plate; The radius of the arc segment; This refers to the elastic modulus of steel.

[0063] Further, in step 7: optimization measures and replaceable design, based on the performance verification results, the following optimization measures and replaceable design are adopted for the graded yield energy dissipation connection device:

[0064] The connection area between the X-shaped bending energy dissipation plate and the straight section, as well as the potential plastic hinge area of ​​the arc section of the annular energy dissipation component, are structurally reinforced and optimized in detail to ensure that they can stably develop plastic deformation as designed under seismic loading and fully utilize their energy dissipation capacity. The X-shaped bending energy dissipation plate and the annular energy dissipation component are designed as replaceable parts after the earthquake, and their connection with the external support end plate adopts a detachable high-strength bolt connection to ensure that the residual inter-story drift angle of the overall structure after a major earthquake can meet the requirement of less than 0.5%, which allows for simple and efficient inspection and replacement, and ensures that the seismic performance of the structure is restored to the design level after repair.

[0065] In summary, the present invention has the following advantages:

[0066] During minor earthquakes, the X-shaped bending energy-dissipating plate dissipates energy independently; during moderate earthquakes, both the plate and the ring-shaped energy-dissipating plate dissipate energy together; and during major earthquakes, the plate dissipates energy as a whole. This effectively copes with earthquakes of various magnitudes, meeting the seismic fortification goals of no damage in minor earthquakes, repairability in moderate earthquakes, and no collapse and repairability in major earthquakes. It solves the problems of single energy dissipation and unstable energy dissipation capacity of traditional energy-dissipating components. The combination of the X-shaped bending energy-dissipating plate and the ring-shaped energy-dissipating component is simple, with clear force transmission, requiring no complex processing technology, and facilitating industrial production. The energy dissipation connection provides additional damping ratio, improves the overall structural stiffness, reduces structural displacement response, and lowers seismic costs. The energy dissipation connection is detachable through high-strength bolts, requiring only replacement of the damaged energy-dissipating component (graded yielding energy dissipation connection device) after an earthquake, without major repairs to the main structure, reducing maintenance costs and shortening structural recovery time. The X-shaped bending energy-dissipating plate exhibits stable hysteretic performance with a full curve and large plastic deformation, and solves the out-of-plane buckling problem of traditional strip dampers; the energy dissipation capacity and out-of-plane buckling resistance of the ring-shaped energy-dissipating component are significantly improved. When combined, the load-displacement hysteresis curve of the entire energy-dissipating connection is full, exhibiting good elasto-plastic performance. This allows it to absorb more seismic energy under earthquake loads, enhancing the structure's seismic energy dissipation capacity. This energy-dissipating connection device can be flexibly connected to supports via gusset plates, making it suitable for critical components such as beam-column joints in various frame structures. Furthermore, the design methodology, through performance ratio optimization and parameter adjustment, allows for customized design of energy-dissipating connection parameters based on the seismic fortification intensity, structural form, and site conditions of different projects, improving the technology's applicability and flexibility. Attached Figure Description

[0067] Figure 1 This is a schematic diagram of the structure of the graded yielding energy dissipation device of the present invention.

[0068] Figure 2 This is a three-segment skeleton curve diagram of the graded yield energy dissipation device of the present invention.

[0069] Figure 3 This is a hysteresis curve diagram of the graded yield energy dissipation device of the present invention.

[0070] Figure 4 This is a schematic diagram of the stiffness of the graded yielding energy dissipation device of the present invention.

[0071] Figure 5 This is a schematic diagram of the X-shaped support with a replaceable graded yielding energy dissipation device according to the present invention.

[0072] Figure 6 This is an exploded schematic diagram of the X-shaped support with a replaceable graded yield energy dissipation device according to the present invention.

[0073] Figure 7 This is a force diagram of the X-shaped support with a replaceable graded yield energy dissipation device in this invention.

[0074] Figure 8This is a buckling timing diagram of the X-shaped support with a replaceable graded yield energy dissipation device according to the present invention.

[0075] Figure 9 This is a schematic diagram of the structure of an X-shaped bending energy-dissipating plate.

[0076] Figure 10 The diagram shows the deformation of the X-shaped bending energy dissipation plate along the z-axis. (a) is the front elevation of the X-shaped bending energy dissipation plate, (b) is the side elevation of 1-1, and (c) is the side elevation of 2-2.

[0077] Figure 11 This is a schematic diagram of the stress and deformation of an X-shaped bending energy-dissipating plate.

[0078] Figure 12 The restoring force model for an X-shaped bending energy-dissipating plate.

[0079] Figure 13 The diagram shows the structure of the annular energy-consuming component, where (a) is the front elevation view of the annular energy-consuming component and (b) is the side elevation view of the annular energy-consuming component.

[0080] Figure 14 The restoring force model for a ring-shaped energy-consuming component.

[0081] Figure 15 This is a simplified mechanical diagram of the X-shaped support with a replaceable graded yielding energy dissipation device according to the present invention.

[0082] Figure 16 This is a schematic diagram of an X-shaped support structure with a replaceable graded yielding energy dissipation device in an embodiment of the present invention.

[0083] Figure 17 This is a detailed dimension drawing of the graded yield energy dissipation device in the embodiment of the present invention, wherein (a) is the front elevation view of the device and (b) is the side elevation view of 1-1.

[0084] Figure 18 This is a finite element hysteresis curve of an X-shaped support with a replaceable graded yield energy dissipation device in an embodiment of the present invention.

[0085] In the picture:

[0086] 1- Annular energy-consuming component, 11- Straight section, 12- Arc section, 2- X-type bending energy-consuming plate, 3- High-strength bolt, 4- End plate, 5- Node plate, 6- Support. Detailed Implementation

[0087] The graded yield energy dissipation connection device of this invention, through its unique structural design, can be flexibly arranged at key locations such as beam-column joints in frame structures, achieving integrated operation with the structure. This allows the graded yield energy dissipation connection device to directly withstand and dissipate the energy generated by seismic forces, thereby more effectively controlling the structural response. Furthermore, through the graded yield design, under minor earthquakes, the lower yield point components first dissipate energy, reducing structural damage; under moderate earthquakes, the higher yield point components are activated sequentially, providing additional energy dissipation capacity. Under major earthquakes, the entire energy dissipation device enters plastic energy dissipation mode, ensuring structural safety. The corresponding design method allows engineers to optimize the device's location and parameters according to specific engineering needs, further improving its applicability and effectiveness.

[0088] The present invention will now be described in further detail.

[0089] A graded yielding energy dissipation connection device, such as Figure 1 , Figure 5 , Figure 6 , Figure 7 As shown, it includes a fixed support, an upper beam, a lower beam, two steel columns, and a graded yield energy dissipation device; the graded yield energy dissipation device includes an X-shaped bending energy dissipation plate 2 and an annular energy dissipation component 1;

[0090] The annular energy-dissipating component 1 is formed by welding two round-end energy-dissipating segments together, which improves energy dissipation capacity and out-of-plane buckling resistance. Each round-end energy-dissipating segment includes an arc segment 12 and a straight segment 11.

[0091] Two straight sections are respectively provided with end plates 4 on their outer sides, and the two straight sections are connected to their respective end plates 4 by high-strength bolts 3.

[0092] Each of the two end plates 4 has a node plate 5 on its outer side, with one side of the node plate 5 vertically welded to the middle of the end plate 4. Two obliquely arranged supports 6 are welded to the web of each node plate 5. The four supports 6 are distributed in an X-shape, forming an X-shaped support frame with a graded yielding energy dissipation connection device, used to connect to external structures, such as... Figure 7 As shown.

[0093] The X-shaped bending energy dissipation plate 2 is welded to the inner sides of two straight sections at both ends. Its width changes linearly from narrow in the middle to wide at both ends, and is proportional to the bending moment distributed along the height. In this embodiment, two X-shaped bending energy dissipation plates are arranged inside an annular energy dissipation component.

[0094] Two steel columns are spaced apart on fixed supports. The upper beam and lower beam are horizontally connected to the two steel columns respectively. The upper beam is located above the lower beam. The ends of the four supports are connected to the intersections of the upper beam, lower beam and the two steel columns respectively.

[0095] The thickness of the X-shaped bending energy-consuming plate 2 ranges from 6 to 18 mm and is made of Q235 steel; the thickness of the ring-shaped energy-consuming component 1 ranges from 6 to 18 mm and is made of Q235 steel.

[0096] The X-type bending energy dissipation plate 2 exhibits stable hysteresis performance, a full curve, and large plastic deformation. It also possesses a certain initial stiffness, demonstrating excellent energy dissipation performance and solving the out-of-plane buckling phenomenon that occurs in traditional strip dampers.

[0097] The combination of the X-shaped bending energy dissipation plate 2 and the ring-shaped energy dissipation component 1 has a simple structure, convenient design, good hysteresis performance, strong deformation capacity, and is connected to the support by high-strength bolts 3 to form an energy dissipation connection. It is easy to replace after an earthquake and has the ability to recover.

[0098] The "Technical Code for Energy Dissipation and Vibration Reduction in Buildings" stipulates that energy dissipation and vibration reduction structures designed and constructed according to the code should meet the seismic fortification objectives of no damage in minor earthquakes, repairability in moderate earthquakes, and no collapse in major earthquakes. For energy dissipation devices in the vibration reduction structure, they should function normally under the influence of frequent earthquakes and fortification earthquakes, and should not lose their function under the influence of rare earthquakes. Based on this, this invention aims to ensure that the X-shaped supported steel frame structure with graded yielding energy dissipation connection devices can meet the objective of repairability even under major earthquakes. Therefore, the following design principles are proposed:

[0099] (1) Under the action of frequent earthquakes, the steel beams, steel columns and supports of the X-shaped support steel frame structure with graded yield energy dissipation connection device are in an elastic state. The first yield point, namely the X-shaped bending energy dissipation plate, yields and enters plastic energy dissipation. It can continue to be used after the earthquake without replacement. At this time, the X-shaped support mainly provides lateral stiffness for the structure.

[0100] (2) Under the design earthquake action, the steel beams, steel columns and supports of the X-shaped support steel frame structure with graded yield energy dissipation connection device are in an elastic state. The second yield point, i.e. the ring energy dissipation component, enters the plastic state and dissipates energy together with the X-shaped energy dissipation plate. It can continue to be used after the earthquake without replacement. At this time, the X-shaped support mainly provides lateral stiffness for the structure.

[0101] (3) Under rare earthquake conditions, the steel beams of the X-shaped braced steel frame structure with graded yielding energy dissipation connection devices are in a state of slight damage, while the supports and steel columns remain intact and in an elastic state. The energy dissipation connection as a whole enters a state of plastic energy dissipation, controlled at moderate damage, and still functions normally, meeting the requirement of post-earthquake replacement. The buckling sequence is as follows: Figure 8 As shown.

[0102] Table 1 Performance Targets

[0103]

[0104] Energy consumption principle:

[0105] For ease of study, the energy-consuming connection is separated in the calculation, and the stress and theoretical formulas for the X-shaped bending energy-consuming plate and the ring-shaped energy-consuming component are calculated separately.

[0106] (a) X-shaped bending energy dissipation plate

[0107] X-shaped bending energy-dissipating panels utilize out-of-plane bending to generate plastic deformation and dissipate energy. Their structure is as follows: Figure 9 As shown, the boundary conditions of the X-shaped bending energy dissipation plate can be considered as two fixed segments, and the schematic diagrams in the xy, xz, and yz directions are respectively shown in the figure. Figure 10 As shown in (a), (b), and (c), the deformation is illustrated when displacement occurs in the z-direction. Figure 11 As shown, the X-shaped bending energy-dissipating plate has a uniform thickness, and its width varies linearly from the middle to both ends, proportional to the bending moment M distributed along the height. This ensures that the X-shaped bending energy-dissipating plate section yields uniformly and simultaneously across the entire height. Its restoring force model can be simplified to an ideal elastoplastic model, as follows: Figure 12 As shown.

[0108] Referring to existing literature on the calculation formulas for the mechanical properties of X-shaped bending energy dissipation plates, the yield load of X-shaped bending energy dissipation plates is... Initial stiffness and yield displacement The calculation formula is

[0109] ;

[0110] ;

[0111] ;

[0112] In the formula, This refers to the normal stress on the surface of the steel. The width of the steel plate; The thickness of the steel plate; This refers to the height of the steel plate. This refers to the number of X-shaped bending energy-dissipating panels; This refers to the elastic modulus of steel.

[0113] (ii) Ring-shaped energy-consuming components

[0114] The annular energy-dissipating component dissipates energy by causing plastic deformation of the arc segment through the vertical displacement of the end plate, such as... Figure 13 As shown. When the energy-consuming component is subjected to vertical shear force, it is constrained by the end plates on both sides. In order to carry out theoretical derivation, the following assumptions are made: (1) The deformation of the steel is linear elastic and the deformation is small; (2) Only the bending section is deformed, and the straight section only has horizontal displacement; (3) The bending section of the energy-consuming component is still a circular arc after deformation.

[0115] Scholars have already theoretically derived the stress conditions of the circular arc segment. Based on these improvements, a new formula for a ring-shaped energy-dissipating component is proposed as follows:

[0116] ;

[0117] ;

[0118] ;

[0119] In the formula, This refers to the normal stress on the surface of the steel. The width of the arc-shaped plate; The thickness of the steel plate; The radius of the arc segment; This refers to the elastic modulus of steel.

[0120] The restoring force model for the annular energy-dissipating component adopts an ideal elastic-plastic model, such as... Figure 14 As shown.

[0121] The design method with replaceable graded yielding energy dissipation connections aims to ensure that under seismic loading, the energy dissipation connections can yield and dissipate energy in a predetermined sequence (first the X-shaped bending energy dissipation plate, then the annular energy dissipation component), while ensuring that the supporting members themselves remain elastic. The specific design steps are as follows:

[0122] Under seismic loading, for an X-type braced frame with replaceable graded yielding energy dissipation connections, the frame undergoes horizontal lateral displacement, and the supports bear different internal forces, such as... Figure 15 As shown, the two diagonally opposite supports are subjected to tension, while the other two diagonally opposite supports are subjected to compression; the axial forces generated by the horizontal load on the four steel supports converge at the energy dissipation connection. After the force is decomposed, the horizontal forces are balanced in the horizontal direction, and shear force acts on the graded yield energy dissipation device in the vertical direction.

[0123] Step 1: Determine the design objectives and loads

[0124] Based on the seismic fortification intensity, fortification category, and performance objectives of the building's location, the levels of frequent earthquakes (minor earthquakes) and fortified earthquakes (moderate earthquakes) that the structure needs to withstand are determined. Through structural analysis, the target inter-story drift angle, base shear force, and apex displacement of the frame under various levels of seismic loading are calculated.

[0125] Step 2: Calculate the key parameters of the support system

[0126] 2.1 Determine the arrangement angle of the X-shaped support (the angle between the support and the horizontal plane) ), cross-sectional size and material strength;

[0127] 2.2 Calculation of axial force of the support in elastic yield state and ultimate state and ,

[0128] 2.3 Calculate the vertical shear force components corresponding to the support. and ;Right now ;

[0129] Step 3: Design the yield load of the graded yield energy dissipation device

[0130] Design yield load of X-shaped bending energy dissipation plate under minor earthquake action: It should meet the following requirements: ,in, This corresponds to the vertical shear force generated when the support reaches elastic yield under minor earthquake conditions. The safety factor for the X-shaped bending energy dissipation plate is to ensure that the X-shaped bending energy dissipation plate can preferentially enter the plastic state under minor earthquakes;

[0131] Design yield load of ring-shaped energy dissipation component under moderate earthquake action: It should meet the following requirements: ,in, This corresponds to the vertical shear force of the support under moderate earthquake conditions. The safety factor for the ring-shaped energy-consuming component must be guaranteed. This causes the annular energy-dissipating component to begin to yield significantly only during moderate earthquakes;

[0132] Under strong earthquake conditions: Under strong earthquake conditions, both the X-shaped bending energy dissipation plate and the annular energy dissipation component enter the plastic state and work together. The combined ultimate bearing capacity of the two is... ,in, This refers to the vertical shear force when the support reaches its ultimate state under a major earthquake. The overall safety factor ensures the safety margin of the structure under major earthquakes.

[0133] 3.1 Design of the first-stage yield load of the graded yield energy dissipation device Under minor earthquake action, the following should be satisfied: ,in, This corresponds to the vertical shear force generated when the support reaches elastic yield under minor earthquake conditions. The safety factor for the X-shaped bending energy dissipation plate is to ensure that the X-shaped bending energy dissipation plate can preferentially enter the plastic state under minor earthquakes;

[0134] 3.2 Design of the second-stage yield load for the graded yield energy dissipation device Under moderate earthquake action, the following should be satisfied: ,in, This corresponds to the vertical shear force of the support under moderate earthquake conditions. The safety factor for the ring-shaped energy-consuming component must be guaranteed. This causes the annular energy-dissipating component to begin to yield significantly only during moderate earthquakes;

[0135] 3.3 Design of the ultimate bearing capacity of the graded yield energy dissipation device Under the action of a major earthquake, both the X-shaped bending energy dissipation plate and the ring-shaped energy dissipation component enter the plastic state and work together. The combined ultimate bearing capacity of the two is... ,in, This refers to the vertical shear force when the support reaches its ultimate state under a major earthquake. The overall safety factor ensures the safety margin of the structure under major earthquakes.

[0136] Step 4: Define and determine the key stiffness ratio and strength ratio;

[0137] To accurately control component performance, the following stiffness ratio and strength ratio are used in the design:

[0138] First stiffness ratio: Initial bending stiffness of the X-shaped bending energy dissipation plate Equivalent vertical stiffness of the support system at the nodes The ratio should be controlled as follows: ;

[0139] Second stiffness ratio: Initial stiffness of the ring-shaped energy dissipation component Equivalent vertical stiffness of the support system at the nodes The ratio should be controlled as follows: ;

[0140] First strength ratio: Yield load of X-shaped bending energy dissipation plate Vertical shear force component at support yielding The ratio should be controlled as follows: ;

[0141] Second strength ratio: Yield load of the ring-shaped energy-dissipating component Vertical shear force component at support yielding The ratio should be controlled as follows: ;

[0142] Step 5: Design the dimensional range of the X-shaped bending energy-dissipating plate and the ring-shaped energy-dissipating component;

[0143] Step 6: Based on the performance verification results, clarify the construction measures and connection details;

[0144] Ensure that the connection of the X-shaped bending energy-dissipating plate meets the following requirements: the connection between the two ends of the X-shaped bending energy-dissipating plate and the straight section of the annular energy-dissipating component adopts a full penetration groove weld. The strength design of the weld should follow the principle of "equal strength" or "strong connection, weak component", that is, the load-bearing capacity of the weld is not lower than the yield capacity of the base material, ensuring that the plastic hinge develops fully on the energy-dissipating plate body, rather than failing prematurely at the weld.

[0145] The structure of the plastic zone of the annular energy-consuming component should meet the following requirements: the connection between the arc segment and the straight segment of the annular energy-consuming component must be a smooth arc transition, and the inner radius R of the arc should not be less than twice the thickness t of the plate, so as to reduce stress concentration and guide the plastic deformation to be evenly distributed throughout the arc segment; in the expected plastic deformation area such as the arc segment, the surface of the plate should be flat and free from defects such as cracks and delamination that affect the plastic development.

[0146] Step 7: Optimization Measures and Replaceable Design. Based on the performance verification results, the following optimization measures and replaceable designs are adopted for the graded yield energy dissipation connection device:

[0147] The potential plastic hinge areas, such as the connection area between the X-shaped bending energy dissipation plate and the straight section, and the arc section of the annular energy dissipation component, are structurally strengthened and optimized in detail to ensure that they can stably develop plastic deformation as expected under seismic loading and fully utilize their energy dissipation capacity. The X-shaped bending energy dissipation plate and the annular energy dissipation component are designed as replaceable parts after the earthquake, and their connection with the external support end plate adopts a detachable high-strength bolt connection to ensure that the residual inter-story drift angle of the overall structure after a major earthquake can meet the requirement of less than 0.5%, which can be easily and efficiently inspected and replaced, and ensure that the seismic performance of the structure is restored to the design level after repair.

[0148] Compared to traditional metal dampers, which have only one yield point and a single energy dissipation method, graded yield energy dissipators possess multiple lines of defense, enabling them to more effectively cope with earthquakes of varying magnitudes and achieve the performance design goal of graded energy dissipation under different seismic loads. Graded yield energy dissipators have greater initial stiffness and yield load, exhibiting excellent elasto-plastic properties, a more robust load-displacement hysteresis curve, and stronger energy dissipation capacity, allowing them to absorb more seismic energy during earthquakes.

[0149] Compared to ordinary support frames, X-shaped supports with replaceable graded yield energy dissipation connections do not experience a sudden drop in stiffness after buckling. Energy dissipation is concentrated at the graded yield energy dissipation connections, and these components can be quickly replaced after an earthquake. Compared to pure frames, X-shaped supports with replaceable graded yield energy dissipation connections exhibit better hysteretic performance and greater stiffness. This invention has a simple construction, clear force transmission, and good economic benefits. The energy dissipation connections have obvious graded yield characteristics, enabling the achievement of graded energy dissipation performance design goals under different seismic loads. They also possess good hysteretic performance, concentrating plastic damage on the energy dissipation components and effectively preventing damage to the main support structure.

[0150] Specific examples are as follows Figure 16 As shown;

[0151] This node is complex and robust in construction and can be divided into three main functional systems:

[0152] 1. Core energy-consuming system: X-shaped support and graded yielding energy-consuming connection device;

[0153] Graded yield energy dissipation connection device: located at the geometric center of the entire node, it is the core of the invention, such as... Figure 17 As shown, it is connected to the surrounding node plates by 10.9 grade M24 high-strength bolts. Internally, it contains the aforementioned annular energy-dissipating component and two X-shaped bent energy-dissipating plates. The specific parameters of the annular energy-dissipating component are as follows: two round-ended energy-dissipating sections, each consisting of an arc section and a straight section. The arc section has a diameter of 200mm and a thickness of 14mm, while the straight section has a length of 145mm and a thickness of 14mm. The transition area between the arc and straight sections is 10mm long, and the thickness is consistent with both the arc and straight sections, using a smooth connection with a radius of 10mm. The X-shaped bent energy-dissipating plate has a height of 172mm, a middle section height of 36mm, a width of 200mm, a middle section width of 50mm, and a thickness of 14mm.

[0154] X-shaped bracing: Four box-shaped support members with a cross section of 100x5 are arranged in an X-shape. One end of each member is connected to the central energy-dissipating component via a gusset plate, while the other end is connected to the beams, columns, or specially designed gusset plates of the main frame, forming a stable lateral force resisting truss system.

[0155] 2. Main frame system: beams, columns, and load transfer plates

[0156] Steel columns: 180x10 box-shaped sections are used as the vertical core load-bearing components of the nodes.

[0157] Steel beams: Variable cross-section steel beams are adopted. GL1-1 is hot-rolled H-beam HN180x150x6x8, and GL1-2 is box section 180x6, forming a rigid connection with the column.

[0158] Node plates and end plates: These are made of steel plates of various thicknesses (t=10, 12, 16, 20) and welded to the ends of beams, columns, and supports, playing a crucial role in force transfer and diffusion. For example, node plate 1 (t=12) and node plate 2 (t=12) are used to reliably transfer the forces from the upper and lower supports to the steel bottom beam and foundation; the bottom plate (t=30) is the thickest force-transfer plate at the bottom of the node, transferring the load to the substructure.

[0159] 3. Strengthening System: Stiffening Ribs

[0160] Multiple stiffening ribs (such as stiffening ribs 2 and 4) with thicknesses ranging from 10mm to 20mm are installed at key stress concentration and load transfer points. These stiffening ribs are welded to the column walls, beam flanges, or gusset plates, and their core function is to prevent local buckling or deformation of the column walls or plates under large concentrated forces, and to ensure that the load is smoothly transferred from the supports and beams to the column.

[0161] II. Mechanical Properties and Working Principle

[0162] This embodiment exhibits excellent mechanical properties, and its effective hysteresis curve is as follows: Figure 18 As shown, its working principle perfectly matches the seismic design concept of graded yielding:

[0163] 1. Implementation of the graded yield energy dissipation mechanism:

[0164] During the minor earthquake (frequent earthquake) phase: the vertical shear force acting on the nodes is relatively small. At this time, the X-shaped bending energy dissipation plate inside the graded yielding energy dissipation connection device undergoes out-of-plane bending yielding first due to its lower yield threshold, and begins to dissipate energy. The outer box-type supports, beams, columns, and all stiffeners remain elastic. After the earthquake, the structure remains functionally intact and requires no repair.

[0165] During the moderate earthquake (design earthquake) stage: seismic forces intensify, and nodal shear forces increase. The annular energy-dissipating component in the graded yielding energy-dissipating connection device begins to undergo plastic deformation, working together with the already yielded X-shaped bending energy-dissipating plate. The hysteresis loop area increases, and the energy dissipation capacity is significantly improved. The main support and frame remain in an elastic state, effectively protecting the main load-bearing components.

[0166] During a major earthquake (rare earthquake) phase: the nodes bear the maximum shear force. The graded yielding energy dissipation connection device as a whole fully develops plasticity, forming a full and stable composite hysteresis curve, providing huge damping force and greatly dissipating the seismic energy input into the structure. At this time, the robust external constraints formed by the base plate, dense stiffening ribs, and strong node plates ensure that plastic deformation is strictly limited within the replaceable energy dissipation components, achieving "damage control." As the seismic force intensifies, the energy dissipation components continue to deform and dissipate energy. When the maximum residual displacement angle allowed by the code is reached, i.e., the residual inter-story drift angle is just less than 0.5%, the high-strength bolts of the energy dissipation components can be loosened, and the central energy dissipation component can be replaced. Through simple and efficient measures, the structure can be restored to its original performance.

[0167] 2. Construction guarantees performance:

[0168] Anti-instability design: The box-type support section has excellent resistance to compressive buckling. The dense stiffening ribs in the node area effectively prevent local buckling of the plate, ensure the stability of force flow transmission, and enable the energy dissipation components to work stably in the predetermined mode.

[0169] Rapid recoverability: The energy-consuming component is connected to the surrounding node plate by bolts and is the only non-welded key force transmission link in the node, which provides a fundamental structural basis for achieving rapid post-earthquake repair.

[0170] In summary, this embodiment is not merely a simple connection detail, but a highly complex and reliable steel structure system node integrating a graded yield energy dissipation device. It transforms the theoretical concept of graded energy dissipation into a practical engineering solution through precise structural design (X-shaped supports, multiple stiffening ribs, force transmission via node plates, and bolted energy dissipation components), fully validating the effectiveness and superiority of this invention in achieving the two major goals of "multiple seismic defense lines" and "rapid post-earthquake functional recovery." The specific dimensions shown in the figures also indicate that this design is suitable for large-span spatial structures in practical engineering projects.

[0171] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A graded yielding energy dissipation connection device, characterized in that: Includes fixed supports, upper beam, lower beam, two steel columns, and graded yield energy dissipation device; The graded yield energy dissipation device includes an X-shaped bending energy dissipation plate and an annular energy dissipation component; The annular energy-consuming component includes two sets of round-end energy-consuming sections arranged opposite to each other. The two sets of round-end energy-consuming sections are connected by a V-shaped butt weld. Each round-end energy-consuming section includes an arc segment and a straight segment. The width of the straight segment is greater than the width of the arc segment. There is a short transition area between the arc segment and the straight segment, which is smoothly connected by rounded corners; The two straight sections are each equipped with an end plate on their outer side, and the straight sections are connected to the end plates by high-strength bolts. The end plate and the node plate are perpendicular and fixed by welding. The node plate is used to connect to four externally inclined X-shaped supports to form an X-shaped support frame with a graded yielding energy dissipation connection device. The X-shaped bending energy dissipation plate is connected to the inner sides of two straight sections at both ends. Its width changes linearly from narrow in the middle to wide at both ends, and is proportional to the bending moment distributed along the length of the plate. Two steel columns are spaced apart on fixed supports. The upper beam and lower beam are horizontally connected to the two steel columns respectively. The upper beam is located above the lower beam. The ends of the four supports are connected to the intersections of the upper beam, lower beam and the two steel columns respectively. When the X-shaped support frame undergoes horizontal lateral displacement under seismic loading, the axial forces generated by the horizontal loads of the four supports converge at the energy-dissipating connection, balancing the horizontal forces in the horizontal direction. The shear force in the vertical direction acts on the graded yielding energy-dissipating device. Under minor earthquakes, the X-shaped bending energy-dissipating plate dissipates energy through out-of-plane bending and plastic deformation, and can be used after the earthquake without replacement. Under moderate earthquakes, the annular energy-dissipating component undergoes plastic deformation of the arc segment through the vertical displacement of the end plate, dissipating energy together with the X-shaped bending energy-dissipating plate, and can be used after the earthquake without replacement. Under major earthquakes, the X-shaped bending energy-dissipating plate and the annular energy-dissipating component yield together and enter into plastic energy dissipation. If the residual inter-story drift angle of the overall structure after a major earthquake is less than 0.5%, it can be easily and efficiently inspected and replaced, ensuring that the seismic performance of the structure is restored to the design level after repair.

2. The graded yielding energy dissipation connection device according to claim 1, characterized in that: The outer middle of the end plate is vertically welded to the side of the node plate, and the four supports are welded to the two node plates in an X shape.

3. The design method of the graded yielding energy dissipation connection device according to claim 1 or 2, characterized in that: Includes the following steps: Step 1: Determine the performance targets and seismic requirements of the ordinary cross-braced frame structure. Based on the seismic fortification intensity, fortification category and expected structural performance level of the building structure's location, determine the response of the ordinary braced frame structure under minor, moderate and major earthquakes, including the inter-story drift angle limit, base shear force and top displacement under each level of earthquake. Step 2: Calculate the vertical force of the ordinary cross-braced frame system. Based on the seismic requirements and target performance indicators determined in Step 1, calculate the axial force generated by the X-shaped support frame under various levels of seismic action, and then determine the vertical shear force component acting on the energy dissipation device with the energy dissipation connection support frame. Step 3: Design the parameters of each level of energy dissipation element based on the concept of graded yielding. According to the vertical shear force requirement obtained in Step 2, determine the range of variation of yield load and stiffness of X-shaped bending energy dissipation plate and ring energy dissipation element respectively, according to the graded yielding sequence of X-shaped bending energy dissipation plate yielding energy dissipation under minor earthquake, ring energy dissipation element yielding and participating in energy dissipation under moderate earthquake, and graded yielding energy dissipation device jointly dissipating energy under major earthquake. Step 4: Determine the stiffness ratio and strength ratio of the graded yield energy dissipation device to ensure the realization of the graded yielding sequence and that the structure has good energy dissipation efficiency, and reasonably control the stiffness and strength ratio relationship between the graded yield energy dissipation device and the main support system. Step 5: Determine the dimensions of the X-shaped bending energy dissipation plate and the ring-shaped energy dissipation component. Based on the yield load determined in Step 3 and the stiffness ratio and strength ratio determined in Step 4, design the size range of the X-shaped bending energy dissipation plate and the ring-shaped energy dissipation component. Step 6: Based on the performance verification results, clarify the construction measures and connection details; Ensure that the connection of the X-shaped bending energy dissipation plate meets the following requirements: the connection between the two ends of the X-shaped bending energy dissipation plate and the straight section of the annular energy dissipation component adopts a full penetration groove weld; the strength design of the weld should follow the principle of equal strength or strong connection and weak component, that is, the bearing capacity of the weld should not be lower than the yield bearing capacity of the base material, to ensure that the plastic hinge develops fully on the energy dissipation plate, rather than failing prematurely at the weld. The plastic zone structure of the annular energy-consuming component should meet the following requirements: the connection between the arc segment and the straight segment of the annular energy-consuming component should be a smooth arc transition, and the inner radius R of the arc should not be less than twice the thickness of the plate, so as to reduce stress concentration and guide the plastic deformation to be evenly distributed throughout the arc segment; in the expected plastic deformation area of ​​the arc segment, the plate surface should be flat and free from defects such as cracks and delamination that affect plastic development.

4. The design method according to claim 3, characterized in that: Supporting vertical shear force The calculation formula is obtained from the decomposition of the supporting axial force: ,in, For the axial force of a single support, To determine the angle between the support and the horizontal plane, it is necessary to calculate the axial force of the support under both the elastic yield state and the ultimate state. and Thus, the corresponding vertical shear force components are obtained. and .

5. The design method according to claim 4, characterized in that: Design yield load of X-shaped bending energy dissipation plate under minor earthquake action: It should meet the following requirements: ,in, This corresponds to the vertical shear force generated when the support reaches elastic yield under minor earthquake conditions. The safety factor for the X-shaped bending energy dissipation plate is to ensure that the X-shaped bending energy dissipation plate can preferentially enter the plastic state under minor earthquakes; Design yield load of ring-shaped energy dissipation component under moderate earthquake action: It should meet the following requirements: ,in, This corresponds to the vertical shear force of the support under moderate earthquake conditions. The safety factor for the ring-shaped energy-consuming component must be guaranteed. This causes the annular energy-dissipating component to begin to yield significantly only during moderate earthquakes; Under strong earthquake conditions: Under strong earthquake conditions, both the X-shaped bending energy dissipation plate and the annular energy dissipation component enter the plastic state and work together. The combined ultimate bearing capacity of the two is... ,in, This refers to the vertical shear force when the support reaches its ultimate state under a major earthquake. The overall safety factor ensures the safety margin of the structure under major earthquakes.

6. The design method according to claim 3, characterized in that: Based on the graded yield load determined in step 3, the stiffness ratio and strength ratio of the X-shaped bending energy dissipation plate and the annular energy dissipation component in the graded yield energy dissipation device are reasonably selected as follows to achieve the best balance between controlling the structural response and optimizing energy dissipation efficiency. First stiffness ratio: Initial bending stiffness of the X-shaped bending energy dissipation plate Equivalent vertical stiffness of the support system at the nodes The ratio is controlled as follows: ; Second stiffness ratio: Initial stiffness of the ring-shaped energy dissipation component Equivalent vertical stiffness of the support system at the nodes The ratio is controlled as follows: ; First strength ratio: Yield load of X-shaped bending energy dissipation plate Vertical shear force component at support yielding The ratio is controlled as follows: ; Second strength ratio: Yield load of the ring-shaped energy-dissipating component Vertical shear force component at support yielding The ratio should be controlled as follows: ; Based on the yield load of the X-shaped bending energy dissipation plate Based on the preset plate thickness and material yield strength, the specific variation dimensions are determined through calculation, so that the actual stress condition of the plate matches the ideal design model; Based on the yield load of the ring-shaped energy dissipation component Determine the radius, cross-sectional dimensions, and length of the straight section of the arc segment; adjust the parameters of each component to meet the requirements of steps 3 and 4.

7. The design method according to claim 3, characterized in that: For an X-shaped bending energy-dissipating plate with out-of-plane yield energy dissipation, the calculation of its yield load and yield moment should be clarified, and the geometric dimensions of the steel plate for fabricating the X-shaped bending energy-dissipating plate should be reasonably determined; according to the stress calculation formula for bending, the stress at the cross-section of the steel plate is solved as follows: (1); For height The bending moment at the section; To calculate the distance from the point to the neutral axis of the cross section; For height Moment of inertia about the neutral axis; The bending moments at the top and bottom ends of the plate are as follows: With the same direction, the steel plate can be adjusted to any height. Bending moment at: (2)； but The moment of inertia of the directional section is (3); The width of the steel plate. For the thickness of the steel plate, The height of the steel plate. Substituting formulas (2) to (3) into formula (1) yields the result for any height. The bending stress at the point is: (4); For a specific damper, at a certain moment, only the above formula has the following expression. The variable indicates that the stress magnitude at all points of the same thickness at the same moment is the same, thus proving that all points of the same thickness will reach yield simultaneously. The formula for calculating the yield moment is: (5); in , The yield stress; Substituting formula (3) into formula (5), we can obtain the yield moment as: (6); The maximum bending moment is when At that time, the yield moment is: (7); At this point, the yield load of the energy dissipation panel is: (8); To prevent shear failure of the X-shaped bending energy dissipation plate at the neck, its shear stress needs to be calculated; at the middle height of the X-shaped bending energy dissipation plate Set minimum width at [location] The shear force at that section is Then the maximum shear stress is: (9); in Let be the neck cross-sectional area; according to the Von-Mises yield criterion, the shear strength of the steel is . (10): To prevent shearing damage to the neck, the following must be met: (11); The minimum width of the neck can be obtained. Construction requirements: (12); At the same time neck height Determined by geometric relations: (13); Using the above formulas, the geometric dimensions of the X-shaped bending energy-dissipating plate can be reasonably determined, under the premise of ensuring that bending yielding precedes shear failure, so as to achieve the expected graded yielding and high-efficiency energy dissipation goals.

8. The design method according to claim 3, characterized in that: The restoring force model of the X-shaped bending energy dissipation plate is an ideal elastic-plastic model, and its yield load... Initial stiffness and yield displacement The calculation formula is ； ； ； In the formula, This refers to the normal stress on the surface of the steel. The width of the steel plate; The thickness of the steel plate; This refers to the height of the steel plate. This refers to the number of X-shaped bending energy-dissipating panels; This refers to the elastic modulus of steel.

9. The design method according to claim 3, characterized in that: The restoring force model of the annular energy dissipation component is an ideal elastic-plastic model, and its yield load... Initial stiffness and yield displacement The calculation formula is ； ； ； In the formula, This refers to the normal stress on the surface of the steel. The width of the round-ended energy-consuming section; The thickness of the steel plate; The radius of the arc segment; This refers to the elastic modulus of steel.

10. The design method according to claim 3, characterized in that: Also includes: Step 7: Optimization Measures and Replaceable Design. Based on the performance verification results, the following optimization measures and replaceable designs are adopted for the graded yield energy dissipation connection device: The connection area between the X-shaped bending energy dissipation plate and the straight section, as well as the potential plastic hinge area of ​​the arc section of the annular energy dissipation component, are structurally reinforced and optimized in detail to ensure that they can stably develop plastic deformation as designed under seismic loading and fully utilize their energy dissipation capacity. The X-shaped bending energy dissipation plate and the annular energy dissipation component are designed as replaceable parts after the earthquake, and their connection with the external support end plate adopts a detachable high-strength bolt connection to ensure that the residual inter-story drift angle of the overall structure after a major earthquake can meet the requirement of less than 0.5%, which allows for simple and efficient inspection and replacement, and ensures that the seismic performance of the structure is restored to the design level after repair.

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