A design method for replaceable energy-absorbing tie beams to improve the seismic performance of double-column piers of bridges

Abstract

The present invention provides a design method for a replaceable energy-absorbing tie beam for improving the seismic performance of a double-column pier of a bridge, and relates to the technical field of seismic resistance and shock absorption data processing. By designing key parameters such as shear strength, shear yield energy consumption, flange width-to-thickness ratio and stiffness ratio and strength ratio of an energy-absorbing section, the designed replaceable energy-absorbing tie beam can preferentially dissipate seismic energy through damage and deformation of the energy-absorbing section under the action of small and medium earthquakes. Under the action of a large earthquake, the seismic energy can be dissipated jointly by shear deformation of the energy-absorbing beam section, overall damage of the transverse tie beam, and "limited" plasticity of the pier column, thereby achieving the purpose of expected graded energy consumption. The introduced graded energy consumption differentiation index M1 further enhances the adaptability of the design, and the precise control of the structural performance is achieved by dynamically adjusting the key parameters. After the earthquake, only the damaged part of the replaceable energy-absorbing tie beam needs to be replaced to quickly restore the structural function of the bridge and protect the safety of the bridge.

Description

Technical Field

[0001] The invention relates to the technical field of earthquake resistance and shock absorption data processing, and in particular to a design method for a replaceable energy-absorbing tie beam for improving the earthquake resistance of a double-column pier of a bridge. Background Art

[0002] At present, the rapid recovery of bridge functions after earthquakes has become a research hotspot and frontier in the field of earthquake engineering. The earthquake resistance of bridge structures is gradually changing from anti-vibration design to post-earthquake functional recovery design. The post-earthquake functional recovery of bridges refers to bridge structures that can recover their use functions without or with only a little repair after an earthquake, so as to reduce traffic interruption time, improve earthquake resistance and safety, and reduce subsequent work time and costs; research on recoverable functional bridge structures mainly involves various new structural systems with self-reset characteristics and replaceable and easy-to-replace sacrificial protection systems, such as using the swaying of the structure itself during an earthquake to achieve self-reset, reasonably configuring extracorporeal prestress in the piers to form a self-recovery system, and setting up sacrificial energy dissipation and shock-absorbing devices to protect the main load-bearing structure, so that it can be used with only a little or no repair after an earthquake; replaceable energy-absorbing tie beams include embedded sections, energy-absorbing sections, and connecting sections;

[0003] In the prior art, publication number CN112761061A discloses a steel friction hinge energy-absorbing tie beam structure for double-column piers, including a crossbeam arranged between two pier columns, both ends of the crossbeam are respectively connected to the outer walls of two vertically arranged pier columns through steel sleeves and ear beams, the steel sleeve is sleeved on the outer walls of the pier columns through shear-resistant welds, one end of the ear beam is welded to the outside of the steel sleeve, and the other end is connected to the crossbeam through the pressure applied by prestressed steel bars to form a steel friction hinge structure. The present invention also discloses a construction method for a steel friction hinge energy-absorbing tie beam structure for double-column piers. The steel friction hinge energy-absorbing tie beam structure and its construction method for double-column piers of the present invention are simple and practical, can improve the lateral compressive stability and lateral stiffness of the double-column pier, absorb the earthquake input energy through the plasticity of the tie beam, and reduce the residual deformation of the tie beam by using the superelasticity of the shape memory alloy, and are convenient for repairing the tie beam with residual deformation after an earthquake;

[0004] Double-column pier beam bridges among small and medium-span beam bridges are relatively fragile under earthquakes. In order to ensure that double-column piers have good seismic performance under earthquakes, structural measures, namely reinforced concrete tie beams, are usually set between the piers to reduce the calculated height, thereby reducing the slenderness ratio. At the same time, the tie beams provide lateral constraints for double-column pier bridges, which can protect the piers and other major components from earthquake damage. However, under the action of earthquakes, ordinary reinforced concrete tie beams have residual deformation and difficult-to-repair damage at the connection between the pier bottom and the tie beam before they can play their energy dissipation role. In addition, the piers fail when the tie beams are damaged or fail to play their original role, which brings great difficulties and challenges to the rapid recovery of the bridge structure function after the earthquake.

[0005] The existing technology mainly focuses on traditional seismic fortification measures in terms of the seismic performance of double-column piers of bridges. Although these measures can improve the seismic performance of bridges to a certain extent, they also have some shortcomings:

[0006] Once an energy-absorbing component is damaged, the entire bridge often needs to be repaired in a complicated manner, which is not only time-consuming and labor-intensive, but also has a significant impact on traffic. In addition, energy-absorbing components in the prior art are often integrated with bridge piers, which increases the risk of damage to bridge piers and the difficulty of replacing and repairing energy-absorbing components when a strong earthquake occurs. In addition, traditional energy-absorbing components may cause additional internal forces when subjected to daily loads (such as temperature changes, vehicle loads, etc.), which may have a negative impact on the long-term performance of the bridge.

[0007] Therefore, in view of the limitations of existing technologies, a new energy dissipation tie beam design method is needed. This method should be able to dissipate earthquake energy more effectively, facilitate rapid repair and maintenance after an earthquake, and ensure that bridge piers and energy dissipation tie beams do not generate secondary internal forces under daily loads. At the same time, how to analyze and process the quantifiable parameters A under daily loads such as temperature and automobiles, construct a graded energy dissipation differentiation index M1, and use this index to quantify the shear strength V of the energy dissipation section. h Compared with the shear bearing capacity of ordinary concrete tie beam V cs How to dynamically adjust the parameters in the relationship?

[0008] In summary, the key to improving the seismic performance of double-column piers of bridges lies in designing a reasonable energy-absorbing tie beam structure, which should not only be able to effectively dissipate energy under earthquake action and reduce damage to the main structure, but also be able to be quickly replaced after an earthquake to restore its function, while also maintaining the stability of the internal force of the structure under daily loads; therefore, the present invention proposes a new design method for replaceable energy-absorbing tie beams, which overcomes the shortcomings of the prior art through original structural design and material selection, and provides an innovative solution for the field of bridge seismic design;

[0009] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0010] The object of the present invention is to provide a design method for a replaceable energy-absorbing tie beam for improving the seismic performance of double-column piers of bridges, so as to solve the problems raised in the above-mentioned background technology.

[0011] To achieve the above object, the present invention provides the following technical solutions:

[0012] A design method for a replaceable energy-absorbing tie beam for improving the seismic performance of a double-column pier of a bridge, the specific steps comprising:

[0013] Step S1: Collect the dimensional data of the bridge pier and the ordinary concrete tie beam, and determine the shear bearing capacity V of the ordinary concrete tie beam by calculation. cs ;

[0014] Step S2: Obtain the shear bearing capacity V calculated in step S1 cs , and set the shear strength of the tie beam energy absorption section to V h ;

[0015] Step S3: Using the finite element analysis model, the shear bearing capacity V of the ordinary reinforced concrete tie beam is cs Shear strength V of energy dissipation section h Perform verification and set u1 as the preset coefficient to ensure V h Does not exceed the preset coefficient u1 and V cs Product, if V h >u1×V cs , then re-design the energy consumption section matching;

[0016] Step S4: obtaining quantifiable parameters A of the bridge pier under the effects of temperature and daily vehicle load, and performing analysis and processing to construct a graded energy consumption differentiation index M1, which is used to dynamically adjust u1; and the quantifiable parameters A include temperature parameters, vehicle load parameters, daily load parameters, structural parameters and material parameters;

[0017] Step S5: obtaining a calculation formula for the slenderness ratio of the replaceable energy-absorbing tie beam to perform matching design of the energy-absorbing section;

[0018] Step S6: Set the width-to-thickness ratio of the energy-absorbing section flange to Within, where f y′ is the yield strength of the flange material. If the width-to-thickness ratio of the energy-absorbing flange exceeds Then re-design the energy consumption section matching;

[0019] Step S7: limiting the design width of the connection section to 0.6D-0.8D and the height to 0.8D-1.0D, where D is the diameter of the pier;

[0020] Step S8: Set the energy dissipation section stiffness K h and the connection segment stiffness K l The ratio is limited to the range of 0.1 to 0.25 to achieve graded energy consumption judgment;

[0021] Step S9: Obtain the plastic shear bearing capacity V of the connection segment lp and plastic bending capacity M lp , and limited to M lp≥0.5lΩV h , V lp ≥ΩV h , where l is the clear span of the tie beam and Ω is the overstrength coefficient.

[0022] Furthermore, the temperature parameters include the ambient temperature T and the concrete internal temperature T int ; The ambient temperature parameter and the concrete temperature parameter are marked as WDc1 and WDc2 respectively.

[0023] The vehicle load parameters include vehicle axle weight W axle 、Traffic flow N veh , vehicle speed V veh ; and the vehicle load parameter is marked as QCZh; the calculation formula is as follows:

[0024]

[0025] W axle,j is the vehicle axle weight in the jth period, which is the axle weight of vehicles passing through the bridge per unit time; N veh,j is the traffic flow in the jth period, which is the number of vehicles passing through the bridge per unit time; V veh,j is the vehicle speed in the jth period, is the speed at which vehicles pass through the bridge; n is the number of vehicles passing through the bridge per unit time;

[0026] The daily load parameters include the daily average traffic load L day , peak traffic load L peak and dynamic load factor DLC.

[0027] Furthermore, the daily load parameter is marked as RCHz, and the calculation formula is as follows:

[0028]

[0029] L day is the total vehicle load passing through the bridge in one day; L peak is the maximum vehicle load in a specific time period; DLC is the load magnification factor caused by the dynamic load of the vehicle; L static is the static load of the vehicle;

[0030] The structural parameters include the pier strain ò pier , tie beam strain beam , bridge displacement D bridge ;

[0031] The average value function of the structure's own parameters is marked as JGc, and the calculation formula is as follows:

[0032]

[0033] òpier is the strain of the pier under daily loads; ò beam is the strain of the tie beam under daily loads; D bridge is the displacement of the bridge under loads;

[0034] The material parameters include the concrete strength fc and the yield strength fy of the steel bars;

[0035] The normalization formula for the material parameters is labeled as CLs, and the calculation formula is as follows:

[0036]

[0037] fc is the compressive strength of the actually used concrete; fy is the yield strength of the steel bars; k is a constant used to normalize the material parameters.

[0038] Furthermore, the calculation formula for the defined grading energy dissipation discrimination index M1 is as follows:

[0039]

[0040] Parameter explanation, M1 is the grading energy dissipation discrimination index; N3 is the sampling times of the environmental temperature and the internal temperature of the concrete;

[0041] Set the value range of the grading energy dissipation discrimination index M1 to (0.5, 5). When the value of M1 is close to 0.5, it indicates that the seismic performance of the bridge under daily loads and environmental changes is poor and needs to be further strengthened; when the value of M1 is close to 5, it indicates that the seismic performance of the bridge under various loads and environmental changes is good and the design has achieved the expected grading energy dissipation effect; the intermediate value indicates that the seismic performance of the bridge is at a medium level and needs to be adjusted appropriately according to the actual situation;

[0042] Divide the value range (0.5, 5) of the grading energy dissipation discrimination index M1 into four intervals and describe each interval in detail;

[0043] Interval 1 (0.5 < M1 ≤ 1.5). In this interval, the grading energy dissipation discrimination index M1 is relatively low, indicating that the seismic performance of the bridge under daily loads and environmental changes is poor and needs to be further strengthened; technically, it is necessary to enhance the bridge structure to improve its seismic performance; by increasing the structural strength of the piers and tie beams, effectively improve the overall seismic capacity of the bridge; u1 is increased by at least 25% to ensure the shear strength V of the energy dissipation section h and the shear bearing capacity V of the ordinary concrete tie beam cs have a sufficient gap,

[0044] Interval Two (1.5 < M1 ≤ 2.5), the grading energy consumption discrimination index M1 is at a medium level, indicating that the seismic performance of the bridge under daily loads and environmental changes is relatively stable, but there is still room for improvement; technically, regular maintenance and optimization of the bridge structure are required to improve its seismic performance; by optimizing the structural design of the piers and cross beams, the overall performance of the bridge can be further improved; increase u1 by 10% to strengthen the response of the energy dissipation section;

[0045] Interval Three: (2.5 < M1 ≤ 3.5), within the third interval, the grading energy consumption discrimination index M1 is at a relatively high level, indicating that the seismic performance of the bridge under daily loads and environmental changes is good, but there is still room for optimization; technically, optimization and improvement of the bridge structure are required to further improve its seismic performance; by further optimizing the structural design of the piers and cross beams, the overall performance of the bridge can be improved; if it is expected that the change in environmental temperature or load conditions will cause the M1 value to decrease by 1%, then make a corresponding increase of at least 3% in u1;

[0046] Interval Four: (3.5 < M1 < 5), within the fourth interval, the grading energy consumption discrimination index M1 is at the highest level, indicating that the seismic performance of the bridge under daily loads and environmental changes is very good, and the design has achieved the expected grading energy dissipation effect; technically, maintenance and monitoring of the bridge structure are required to ensure its long-term stability; adjust the u1 value by 2% to ensure that the shear strength V h of the energy dissipation section continues to remain above the optimized level.

[0047] Compared with the prior art, the beneficial effects of the present invention are:

[0048] 1. By designing key parameters such as the shear strength V h of the energy dissipation section, the shear yield strength, the width, thickness, setting spacing of the stiffeners in the energy dissipation section, the width-thickness ratio of the flange in the energy dissipation section, the width of the connection section, and the stiffness ratio and strength ratio between the connection section and the energy dissipation section, it is possible to ensure that no secondary internal forces are generated in the replaceable energy dissipation cross beam and inside the piers under the action of daily loads such as temperature and vehicles.

[0049] Under minor earthquakes, the seismic energy is preferentially dissipated through the damage deformation of the energy dissipation section. Under major earthquakes, the seismic energy is dissipated by the shear deformation of the energy dissipation beam section, the overall damage of the cross beam, and the "limited" plasticity of the pier columns, achieving the purpose of expected grading energy dissipation. After the earthquake, only the damaged part of the replaceable energy dissipation cross beam needs to be replaced to quickly restore the bridge structure function and protect the bridge safety;

[0050] The strength and stiffness of the energy-absorbing section are set lower than those of the connecting section. This setting can prevent the bridge pier from being damaged before the replaceable energy-absorbing tie beam, ensure that the replaceable energy-absorbing tie beam can better play the role of graded energy absorption and shock absorption, make the replaceable energy-absorbing tie beam structure more stable, and better play the role of effective protection for the bridge pier;

[0051] By introducing the graded energy dissipation differentiation index M1, the relationship between the shear strength of the energy dissipation section and the shear bearing capacity of the pier is dynamically adjusted, which improves the design adaptability and energy dissipation performance, reduces maintenance costs, protects the main structure, and achieves refined energy dissipation control, thereby evaluating the seismic performance of the bridge under daily loads and environmental changes;

[0052] 2. Transfer the internal force of the pier to the energy dissipation section through the connecting section;

[0053] The energy-absorbing section is taken as the core damaged energy-absorbing component, and cross-shaped transverse stiffeners and vertical stiffeners are arranged on both sides of the web of the energy-absorbing section to avoid out-of-plane buckling of the web of the core energy-absorbing section, enhance the energy-absorbing effect of the energy-absorbing section, and reduce the damage to the web caused by the weld connection; weakening the strength of the energy-absorbing component can concentrate the damage on the energy-absorbing section to meet the deformation requirements and achieve the purpose of yielding failure before the connection section and the embedded section, while ensuring that the stiffness and bearing capacity of the original structure meet the use requirements, and can reasonably control the damage of the main structure;

[0054] 3. The internal force of the pier is transmitted through the connecting section. The connecting section has the function of graded energy dissipation and improving integrity. The I-shaped steel section has strong shear resistance and is easy to process. The arc-shaped end plate is set to meet the design of the fitting pier, which can perfectly fit the cylindrical double-column pier and increase the force-bearing area to ensure that the internal force of the pier is transmitted to the connecting section;

[0055] 4. Reserve steel bar holes and inner bolt holes on the embedded arc connecting plate. This setting allows the longitudinal steel bars of the pier to pass through the reserved steel bar holes during the construction of the pier, forming a whole with the pier and achieving the effect of fixing the position. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A flow chart of the design method for replaceable energy dissipating tie beams;

[0057] Figure 2 It is a schematic front view of the overall structure of the replaceable energy-absorbing tie beam;

[0058] Figure 3 It is a schematic top view of the overall structure of the replaceable tie beam;

[0059] Figure 4 It is a schematic main view of the energy consumption section structure;

[0060] Figure 5 It is a schematic rear view of the energy dissipation section structure;

[0061] Figure 6 It is the left view of the energy dissipation section structure;

[0062] Figure 7 It is a schematic top view of the energy dissipation section structure;

[0063] Figure 8 The main view of the connecting section structure is shown;

[0064] Fig. 9 The top view of the connecting section structure is shown;

[0065] Fig.10 It is a schematic main view of the embedded section structure;

[0066] Fig.11 It is a schematic top view of the embedded section structure;

[0067] Fig.12 The left view of the embedded section structure is shown;

[0068] Fig.13 This is a schematic diagram of the installation of a replaceable tie beam in Embodiment 2;

[0069] Fig.14 This is a schematic diagram of the installation of a replaceable tie beam in Example 3;

[0070] Fig.15 It is a schematic diagram of the process of the present invention.

[0071] Figure markings: 1-energy absorption section, 2-connecting section, 3-embedded section, 4-pier, 5-cap beam, 6-high-strength bolts, 11-vertical stiffening plate, 12-energy absorption section end plate, 13-energy absorption section flange plate, 14-transverse stiffening plate, 15-energy absorption section web, 16-energy absorption section bolt hole, 21-connecting section stiffening plate, 22-arc end plate, 23-connecting section flange plate, 24-connecting section end plate, 25-connecting section bolt hole, 26-connecting section web, 31-inner sleeve bolt, 32-embedded section end plate, 33-embedded arc connecting plate, 34-reserved steel bar hole, 35-inner sleeve bolt hole. DETAILED DESCRIPTION

[0072] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0073] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0074] Embodiment 1:

[0075] See also Figure 1 and Fig.15 , the present invention provides a technical solution:

[0076] A design method for a replaceable energy-absorbing tie beam for improving the seismic performance of a double-column pier of a bridge, wherein the replaceable energy-absorbing tie beam (referred to as tie beam) comprises a pre-embedded section 3, an energy-absorbing section 1, and a connecting section 2, and the specific steps include:

[0077] Step S1: Collect the dimensional data of the bridge pier and the ordinary concrete tie beam, and determine the shear bearing capacity V of the ordinary concrete tie beam by calculation. cs , where α cv A is the shear bearing capacity coefficient on the inclined section, which is an empirical coefficient used to consider the shear bearing capacity of concrete on the inclined section. In this embodiment, it is taken as 0.7; sv is the total cross-sectional area of ​​each stirrup in the same section; s is the stirrup spacing along the length of the member, b is the web thickness of the energy dissipation section, and f yv is the design value of the tensile strength of the stirrups; it is convenient for the replaceable energy-absorbing tie beam to match the structural design with the seismic performance;

[0078] f t It is the design value of tensile strength of concrete, which indicates the strength of concrete material under tension;

[0079] h0 is the effective height of the tie beam, i.e., the distance from the center of gravity of the tension reinforcement to the compression edge, and is a dimensional parameter of the tie beam cross section;

[0080] Step S2: Obtain the shear bearing capacity V of the ordinary concrete tie beam calculated in step S1 cs , so as to match the structural design of the replaceable energy-absorbing tie beam with the seismic performance, and set the shear strength of the energy-absorbing section to meet Vh =0.6hbf y , where h is the height of the web of the energy-absorbing section, b is the thickness of the web of the energy-absorbing section, and f y is the yield strength of web steel;

[0081] Step S3: Establish a finite element analysis model to verify the shear bearing capacity V of ordinary reinforced concrete tie beams cs Shear strength V of energy dissipation section h , if V h >u1×V cs , it does not meet the graded energy consumption requirements, and the energy consumption section matching design needs to be redesigned, that is, the web height of the energy consumption section is reduced by Δ0.1h, and the web thickness of the energy consumption section is adjusted accordingly and then recalculated; if V h =u1×V cs , the purpose of graded energy consumption is achieved, and the bearing capacity of the bridge pier changes slightly at this time;

[0082] Step S4: Obtain the quantifiable parameter A of the bridge pier under the daily loads such as temperature and automobiles, perform analysis and processing, and construct a graded energy consumption differentiation index M1, which is used to distinguish V h >u1×V cs u1 in is dynamically adjusted; and the quantifiable parameters A include temperature parameters, vehicle load parameters, daily load parameters, structural parameters and material parameters;

[0083] Step S5: Design and limit the shear yield energy consumption of the replaceable energy dissipation tie beam, and specifically obtain the slenderness ratio calculation formula of the replaceable energy dissipation tie beam: Where e is the length of the energy consumption section, M P is the bending bearing capacity, V P is the shear bearing capacity; if or When the energy dissipation section undergoes bending-shear coupling yield and bending yield, the matching design of the energy dissipation section needs to be redesigned, that is, the length of the energy dissipation section is adjusted according to Δ0.1e and then recalculated. When , shear yield occurs in the energy dissipation section, meeting the design requirements;

[0084] The web of the replaceable energy-absorbing tie beam is reinforced to avoid premature yielding. Specifically, stiffening ribs are set to increase the strength. The width of the stiffening ribs is not less than b f / 2-t w , the thickness of the stiffening rib is not less than t w , set the spacing no more than 30t w -h / 5, where b f is the flange width, t w is the web thickness, h is the web height of the energy dissipation section;

[0085] Step S6: Design and limit the flange width and thickness of the replaceable energy-absorbing tie beam to reduce the energy-absorbing section flange buckling, and set the energy-absorbing section flange width-to-thickness ratio to Within, where f y′ is the yield strength of the flange material. If the width-to-thickness ratio of the energy-absorbing flange exceeds Then re-design the energy consumption section matching;

[0086] Step S7: matching design is performed on the replaceable energy-absorbing tie beam connection section and the double-column pier, specifically limiting the connection section to be designed with a width of 0.6D to 0.8D and a height of 0.8D to 1.0D, wherein D is the diameter of the pier column;

[0087] Step S8: To ensure that the plastic deformation of the replaceable energy-absorbing tie beam under earthquake action should be concentrated on the energy-absorbing section, the stiffness ratio and strength ratio of the connecting section and the energy-absorbing section need to be verified. The stiffness K of the energy-absorbing section h and the connection segment stiffness K l The ratio is limited to the range of 0.1 to 0.25, which satisfies the requirement that the bearing capacity of the replaceable energy-absorbing tie beam double-column pier changes little, can realize graded energy absorption, and achieve the purpose of expected damage sequence. If it is not within this range, the connection section structure is adjusted, that is, the web height, thickness, and flange size are adjusted and then recalculated;

[0088] Step S9: Obtain the plastic shear bearing capacity V of the connection segment lp and plastic bending capacity M lp The strength ratio means that the ultimate bending moment and shear force of the connecting section should be greater than the ultimate bending moment and shear force of the energy dissipation section, and is limited to M lp ≥0.5lΩV h , V lp ≥ΩV h , where l is the clear span of the tie beam, Ω is the super strength coefficient, and the energy dissipation section Greater than 1.0, the super strength coefficient Ω is 1.5; if the energy consumption section Less than 1.0, the super strength coefficient Ω is 1.9;

[0089] Step S10: Final confirmation of seismic performance is performed, and a comprehensive seismic performance evaluation of the double-column pier structure of the bridge is performed through a finite element analysis model to ensure that under the action of an earthquake, the structure can achieve the expected energy dissipation and deformation control while maintaining sufficient bearing capacity and stability;

[0090] Step S10.1: If the seismic performance assessment results meet the design requirements, subsequent construction drawings and design documents are prepared to ensure the feasibility and safety of the design solution.

[0091] Step S10.2: If the seismic performance evaluation result does not meet the design requirements, return to step S2, re-design the matching between the energy-absorbing section and the connecting section, and repeat steps S2 to S9 until the seismic performance requirements are met.

[0092] Step S10.3: Complete the final review and approval process of the design plan to ensure that all design steps and technical parameters comply with relevant specifications and standards and are ready to enter the construction phase.

[0093] Embodiment 2:

[0094] For further explanation based on Example 1, please refer to Figure 2-Figure 13 The energy dissipation section 1 is connected to the connection section 2 by high-strength bolts 6, and the connection section 1 is connected to the embedded section 3 by high-strength bolts 6. The embedded section 3 is embedded in the pier 4. The energy dissipation section 1, the connection section 2, and the embedded section 3 are made of steel by welding. It is worth noting that the tie beams in the existing double-column piers of bridges are ordinary reinforced concrete tie beams, which are cast together with the piers to form a whole. Under the action of earthquakes, residual deformation and difficult-to-repair damage are very likely to occur at the connection between the pier bottom and the tie beam. Moreover, the damage of the tie beam after the earthquake or failure to play its original role will lead to the failure of the pier, which brings great challenges to the restoration of the traffic function of the bridge after the earthquake. The replaceable tie beams in this embodiment are made of steel by welding, which have the characteristics of large elastic strain, high strength, and strong material designability. While achieving the same effect as ordinary reinforced concrete tie beams, they can better achieve the seismic isolation effect and improve the seismic performance of double-column pier bridges.

[0095] like Figure 4-Figure 7 As shown, the energy absorbing section 1 is welded by an energy absorbing section end plate 12, a flange plate 13, a transverse stiffening plate 14, a vertical stiffening plate 11, and an energy absorbing section web 15. Bolt holes are reserved on the energy absorbing section end plate 12 for connecting with the connecting section 2. Specifically, the energy absorbing section 1 is welded into an I-shaped steel section, wherein the transverse stiffening plate 14 and the vertical stiffening plate 11 are respectively arranged on both sides of the energy absorbing section web 15 in a cross shape. This structural setting can not only improve the shear strength of the tie beam, but also avoid out-of-plane buckling of the core energy absorbing section web, enhance the energy absorbing effect of the energy absorbing section 1, and reduce the damage of the weld connection to the web 15. Such a structure can improve the service life and reliability, ensure its normal operation, and further reduce the risk of damage to the pier 4.

[0096] The selection of steel material for the web of the energy-absorbing section is also crucial. For example, LY225, LY160 and other steel materials can be selected. In this embodiment, Q235 steel is selected. The energy-absorbing section is used as a core energy-absorbing component to dissipate seismic energy under the action of small and medium earthquakes in actual use. If the energy-absorbing section is damaged after the earthquake, it only needs to replace the energy-absorbing section 1 to quickly restore the bridge structure function and ensure the safety of the bridge.

[0097] It is worth noting that the vertical stiffening plate 11, the transverse stiffening plate 14, and the energy-absorbing section web 15 can all be made of Q235 steel, but they must be weaker than the steel strength of the energy-absorbing section end plate 12, the flange plate 13, the connection section 2, and the embedded section 3, so as to achieve the purpose of yielding and failure before the connection section 2 and the embedded section 3, and protect the bridge pier 4; in order to achieve the replaceability of the tie beam, a bolt hole is reserved on the energy-absorbing section end plate 12, which is set to connect with the connection section 2 to form a whole, and at the same time transmit the internal force of the bridge pier to the energy-absorbing section 1 through the connection section 2;

[0098] like Figure 8 , Fig. 9 As shown, the connection section 2 is welded by an arc-shaped end plate 22, a connection section stiffening plate 21, a connection section flange plate 23, a connection section end plate 24, and a connection section web 26. Bolt holes are reserved on the arc-shaped end plate 22 and the connection section end plate 24, and are respectively connected to the energy dissipation section 3 and the embedded section 1; specifically, the connection section is set to an I-shaped steel section, and the connection section stiffening plates 21 are arranged on both sides of the connection section web. This structural setting can increase the shear bearing capacity of the connection section;

[0099] In order to better realize the replaceability of the bridge, bolt holes are reserved on the arc-shaped end plate 22 and the connecting section end plate 24. This setting is to connect with the energy-absorbing section 1 and the embedded section 3 to form a whole, and at the same time, the internal force of the pier is transmitted to the energy-absorbing section 1 through the connecting section 2. It is worth noting that in order to improve the adaptability of the connecting section 2 and the cylindrical pier 4, the arc-shaped end plate 22 is used to meet the design of fitting the pier 4;

[0100] In actual use, the connecting section 2 has the functions of graded energy dissipation and improving integrity. Under the action of daily loads such as temperature and cars, the connecting section 2 connects the energy dissipation section 1 and the bridge pier 4 as a whole, and no secondary internal force is generated inside the bridge pier; during small and medium earthquakes, the seismic energy received by the pier column is transmitted to the energy dissipation section through the connecting section. During a large earthquake, the energy dissipation capacity of the energy dissipation section is not enough to meet the energy dissipation demand. At this time, the seismic energy is dissipated by the energy dissipation section 1 and the connecting section 2 as a whole. After the earthquake, only the damaged part of the replaceable tie beam needs to be replaced to quickly restore the bridge structure function, achieve the expected purpose of graded energy dissipation, and improve the seismic resistance of the bridge;

[0101] like Figure 10-12 As shown, the embedded section 3 is composed of an inner sleeve bolt 31, an embedded section end plate 32, and an embedded arc-shaped connecting plate 33. Specifically, the embedded section 3 is embedded in the pier 4 to form a whole with the pier. It is worth noting that a steel bar hole 34 and an inner sleeve bolt hole 35 are reserved on the embedded arc-shaped connecting plate 32. The reserved steel bar hole 34 passes through the steel bars inside the pier 4 in advance and is consolidated.

[0102] In actual use, that is, during the pouring of the bridge pier, when the concrete is poured to the designated position, the embedded arc connecting plate 33 is passed through the longitudinal steel bars in the bridge pier through the steel bar holes 34 reserved on the plate to be fixed to the designated position, and then the concrete is poured to complete the installation of the embedded section 3. After the embedded section 3 is installed, high-strength bolts are passed through the inner sleeve bolt holes 35 and the bolt holes reserved in the arc end plate 22 to complete the fixed installation of the connecting section 2.

[0103] like Fig.13 As shown, in this embodiment, the height H of the double-column pier is between 10≤H<20m, that is, a tie beam is arranged between the piers to reduce the bending moment and slenderness ratio of the piers;

[0104] Specifically, the replaceable tie beam is composed of an energy-absorbing section 1, two connecting sections 2 and two embedded sections 3. The two embedded sections 3 are respectively embedded in the double-column piers 4 of the bridge and fixed. The embedded sections 3 on both sides are respectively connected to the connecting sections 2 by high-strength bolts through the embedded arc-shaped connecting plate 33 and the reserved bolt holes 25 of the arc-shaped end plate 22. The energy-absorbing section 1 is connected to the connecting sections 2 on both sides by high-strength bolts through the reserved bolt holes 16 of the energy-absorbing section end plate 12 and the reserved bolt holes 25 of the connecting section end plate 24, so as to form a whole, that is, a replaceable tie beam that improves the seismic resistance of the double-column piers of the bridge, and realizes the replaceability of the double-column piers of the bridge after earthquake damage.

[0105] It is worth noting that compared with traditional reinforced concrete tie beams, which are prone to plastic hinges at the connection between tie beams and piers after an earthquake, and which can easily damage the tie beams and even cause the failure and collapse of pier 4, the replaceable tie beams with this structural setting have a three-level protection function. Under the action of daily loads, the replaceable energy-absorbing tie beams are in a connected state, and no secondary internal forces are generated inside the piers. During small and medium earthquakes, the seismic energy is dissipated through the energy-absorbing section 1. During large earthquakes, the seismic energy is dissipated through the "limited" plasticity of the energy-absorbing section 1, the connecting section 2, and the piers, thus solving the problem of earthquake damage to traditional reinforced concrete tie beams. In addition, the replaceable tie beams are prefabricated in factories using steel, which greatly shortens the construction period of the double-column piers of the bridge.

[0106] Embodiment three:

[0107] For further explanation based on Example 1, please refer to Fig.14 , and also provides another arrangement method of replaceable tie beams for improving the seismic resistance of double column piers of bridges, including:

[0108] In this embodiment, the height H of the double-column pier is between 20≤H<30m, and two tie beams need to be set; specifically, two replaceable tie beams are set between the double-column piers of the bridge to reduce the bending moment and slenderness ratio of the pier column; in actual use, that is, in the process of pouring the bridge pier 4 from bottom to top, when the concrete is poured to the specified position of the first replaceable tie beam, the embedded section 3 of the first replaceable tie beam is embedded and fixed according to the installation method of the embedded section 3 in Example 1, and after the casting of the embedded section 3 and the installation of the connecting section 2 and the energy absorbing section 1 are completed, the casting of the bridge pier 4 is continued; when the concrete is poured to the specified position of the second replaceable tie beam, the embedded section 3 of the second replaceable tie beam is embedded and fixed according to the same installation method, and after the casting of the embedded section 3 and the installation of the connecting section 2 and the energy absorbing section 1 are completed, the casting of the bridge pier 4 is continued.

[0109] Embodiment 4:

[0110] Further explanation based on the first embodiment, the temperature parameters include the ambient temperature T and the internal temperature of the concrete T int ;

[0111] Ambient temperature T: real-time air temperature data, affecting the physical properties of materials;

[0112] Concrete internal temperature T int : The temperature inside the piers and tie beams affects the strength and elastic modulus of concrete;

[0113] The ambient temperature parameter and concrete temperature parameter are marked as WDc1 and WDc2 respectively, and the calculation formula is as follows:

[0114]

[0115] T i′ is the ambient temperature at the i′th time point, and is the ambient temperature data collected in real time; T avg is the average ambient temperature; is the average ambient temperature during the acquisition period; T max is the maximum value of the ambient temperature, which is the maximum value of the ambient temperature during the acquisition period; T min is the minimum value of the ambient temperature during the acquisition period; T int,i′ is the internal temperature of the concrete at the i′th time point, which is the real-time temperature data inside the pier and tie beam; T int,avg is the average concrete internal temperature, which is the average concrete internal temperature during the acquisition period; T int,max is the maximum temperature inside the concrete, which is the maximum temperature inside the concrete during the acquisition period; T int,min is the minimum value of the internal temperature of the concrete, which is the minimum value of the internal temperature of the concrete during the collection period;

[0116] The vehicle load parameters include vehicle axle weight W axle、Traffic flow N veh , vehicle speed V veh ;

[0117] Vehicle axle weight W axle : The axle weight of vehicles passing through the bridge affects the instantaneous load of the bridge;

[0118] Among them, w i is the axle weight of the i-th vehicle, in kilonewtons (kN), and n is the number of vehicles passing the bridge per unit time;

[0119] Traffic flow N veh : The number of vehicles passing through the bridge per unit time affects the cumulative load;

[0120] Where n is the number of vehicles passing through the bridge per unit time, and t is the time interval in hours (h);

[0121] Vehicle speed V veh : The speed of vehicles passing through the bridge affects the dynamic load effect;

[0122] Where, d is the length of the bridge that the vehicle passes through, in meters (m), t travel is the time it takes for a vehicle to pass through the bridge, in seconds (s);

[0123] The vehicle load parameter is marked as QCZh, and the calculation formula is as follows:

[0124]

[0125] W axle,j is the vehicle axle weight in the jth period, which is the axle weight of vehicles passing through the bridge per unit time; N veh,j is the traffic flow in the jth period, which is the number of vehicles passing through the bridge per unit time; V veh,j is the vehicle speed in the jth period, is the speed at which vehicles pass through the bridge; M is the total number of periods;

[0126] The daily load parameters include the daily average traffic load L day , peak traffic load L peak and dynamic load factor DLC;

[0127] Average daily traffic load L day : total vehicle load passing through the bridge in one day;

[0128] Among them, W axle,i is the axle weight of the i-th vehicle, in kilonewtons (kN), and N1 is the total number of vehicles passing through the bridge in one day;

[0129] Peak traffic load Lpeak: the maximum vehicle load in the current specific time period;

[0130] L peak =max(W axle,i ), where W axle,i is the axle weight of any vehicle in a day, in kilonewtons (kN);

[0131] Dynamic load factor DLC: load magnification factor caused by vehicle dynamic load;

[0132] Where ΔL is the load increase caused by the vehicle dynamic load, in kN, L static is the static load of the vehicle, in kilonewton (kN);

[0133] The daily load parameter is marked as RCHz, and the calculation formula is as follows:

[0134]

[0135] L day is the total vehicle load passing through the bridge in one day; L peak is the maximum vehicle load in a specific time period; DLC is the load magnification factor caused by the dynamic load of the vehicle; L static is the static load of the vehicle;

[0136] The structural parameters include the pier strain ò pier , tie beam strain beam , bridge displacement D bridge ;

[0137] Pier strain pier : The strain of bridge piers under daily loads;

[0138]

[0139] Where, ΔL pier is the length change of the bridge pier under load, in meters (m), L pier is the original length of the pier, in meters (m);

[0140] Tie beam strain beam : The strain of the tie beam under daily load;

[0141]

[0142] Where, ΔL beam is the length change of the tie beam under load, in meters (m), L beam is the original length of the tie beam in meters (m);

[0143] Bridge displacement D bridge : The displacement of the bridge under load, reflecting the overall deformation;

[0144] D bridge =max(Δx)

[0145] Wherein, Δx is the displacement of each sampling point of the bridge under the load, in meters (m);

[0146] The average value function of the structure's own parameters is marked as JGc, and the calculation formula is as follows:

[0147]

[0148] ò pier is the strain of the bridge pier under daily load; beam is the strain of the tie beam under daily load; D bridge is the displacement of the bridge under load;

[0149] The material parameters include concrete strength fc and steel bar yield strength fy;

[0150] Concrete strength fc: compressive strength of concrete actually used;

[0151] Steel bar yield strength fy: yield strength of steel bar;

[0152] The normalized formula for the material parameters is marked as CLs, and the calculation formula is as follows:

[0153]

[0154] fc is the compressive strength of concrete actually used; fy is the yield strength of steel bars; k is a constant used to normalize material parameters;

[0155] The calculation formula of the graded energy consumption differentiation index M1 is defined as follows:

[0156]

[0157] Parameter explanation: M1 is the graded energy consumption differentiation index; N3 is the sampling times of ambient temperature and concrete internal temperature;

[0158] The value range of the graded energy consumption differentiation index M1 is set to (0.5, 5). When the M1 value is close to 0.5, it indicates that the seismic performance of the bridge under daily loads and environmental changes is poor and needs to be further strengthened; when the M1 value is close to 5, it indicates that the seismic performance of the bridge under various loads and environmental changes is good, and the design has achieved the expected graded energy consumption effect; the intermediate value indicates that the seismic performance of the bridge is at a medium level and needs to be appropriately adjusted according to the actual situation;

[0159] The value range (0.5, 5) of the graded energy consumption differentiation index M1 is divided into four intervals, and each interval is described in detail; the description of each interval includes technical effects, judgment criteria and rules, as well as quantitative descriptions of interaction rules and value changes;

[0160] The four intervals are divided and set as follows:

[0161] Interval 1 (0.5 <M1≤1.5),

[0162] Description of technical effect: In this range, the graded energy dissipation differentiation index M1 is low, indicating that the seismic performance of the bridge under daily loads and environmental changes is poor and needs to be further strengthened; technically, the bridge structure needs to be strengthened to improve its seismic performance; by increasing the structural strength of the piers and tie beams, the overall seismic capacity of the bridge can be effectively improved; specific measures include increasing the concrete strength fc and the steel yield strength fy; if M1 is close to 0.5, increase the concrete strength and steel yield strength by 20% and 15% respectively, and increase the strain monitoring frequency of the piers and tie beams by 10%; u1 is increased by at least 25% to ensure the shear strength V of the energy dissipation section h Compared with the shear bearing capacity of ordinary concrete tie beam V cs There is enough gap between them to accommodate higher dynamic loads;

[0163] Judging criteria and rules:

[0164] In order to ensure the seismic performance of the bridge within this range, the M1 threshold is set to 1.0; when the M1 value is lower than 1.0, it implies that the current energy dissipation section is not sufficient to cope with potential vibrations. At this time, u1 is increased by 15%. Accordingly, the design of the energy dissipation section is also adjusted to adapt to the new u1 value to ensure that the energy dissipation performance remains at the best state; the following measures need to be taken: If M1≤1.0, the piers and tie beams are reinforced, and the monitoring frequency is increased by 10%. Specific measures include increasing the concrete strength by 20% and the steel yield strength by 15%; If M1>1.0, regular inspections are carried out to maintain the current structural state and regularly monitor the structural strain and displacement;

[0165] Interaction rules and value changes:

[0166] In this range, the ambient temperature T and the concrete internal temperature T int , vehicle axle weight W axle 、Traffic flow N veh , vehicle speed V veh , daily average traffic load L day , peak traffic load L peak 、Pier strain pier , tie beam strain beam and bridge displacement D bridgeThe impact of changes in M1 needs to be considered; if the ambient temperature and the internal temperature of the concrete increase by 10% respectively, the graded energy consumption differentiation index will decrease by 5%; u1 should be increased by 10% to maintain the design advantage of the energy consumption section, if the vehicle axle weight, traffic volume and vehicle speed increase by 15% respectively, M1 will increase by 10%; if the average daily traffic load and the peak traffic load increase by 20% respectively, M1 will increase by 15%; u1 should be increased by 7% to ensure the appropriate margin for seismic performance, if the pier strain and tie beam strain decrease by 10% respectively, M1 will decrease by 5%; if the bridge displacement increases by 20%, M1 will increase by 10%; these interactive rules ensure the dynamic adjustment and optimization of various parameters, so that the seismic performance of the bridge under different load and environmental conditions can be improved;

[0167] Interval 2 (1.5 <M1≤2.5),

[0168] In the second interval, the graded energy dissipation differentiation index M1 is at a medium level, indicating that the seismic performance of the bridge under daily loads and environmental changes is relatively stable, but there is still room for improvement; technically, the bridge structure needs to be regularly maintained and optimized to improve its seismic performance; the overall performance of the bridge can be further improved by optimizing the structural design of piers and tie beams; specific measures include moderately increasing the concrete strength fc and the steel yield strength fy, and when M1 is close to 1.5, increasing the concrete strength and steel yield strength by 10% and 8% respectively, and increasing the strain monitoring frequency of piers and tie beams, and increasing u1 by 10% to strengthen the response of the energy dissipation section;

[0169] Judging criteria and rules:

[0170] In order to ensure the stability of the bridge in this interval, the M1 threshold value of this interval is set to 2.0. When the M1 value is lower than 2.0, u1 is increased by 5%. This will moderately enhance the performance of the energy-consuming section to cope with unexpected loads or environmental changes. The following measures need to be taken: If (M1≤2.0), the piers and tie beams are reinforced and the monitoring frequency is increased. Specific measures include increasing the concrete strength by 5% and the steel yield strength by 4%. If M1>2.0, regular inspections are carried out to maintain the current structural state and regularly monitor the structural strain and displacement.

[0171] Interaction rules and value changes:

[0172] In this range, the ambient temperature T and the concrete internal temperature T int , vehicle axle weight W axle 、Traffic flow N veh , vehicle speed V veh , daily average traffic load L day , peak traffic load L peak 、Pier strain pier , tie beam strainbeam and bridge displacement D bridge The influence of the change on M1 should be considered. If the ambient temperature and the internal temperature of the concrete increase by 10% respectively, the graded energy consumption differentiation index will decrease by 3%; then u1 should be increased by 6% accordingly to ensure the shear strength V h In the ideal range, if the vehicle axle weight, traffic volume and vehicle speed increase by 10% respectively, M1 will increase by 7%; if the average daily traffic load and peak traffic load increase by 15% respectively, M1 will increase by 10%; if the pier strain and tie beam strain decrease by 8% respectively, M1 will decrease by 4%; if the bridge displacement increases by 15%, M1 will increase by 7%; these interactive rules ensure the dynamic adjustment and optimization of various parameters, so that the seismic performance of the bridge under different load and environmental conditions can be stabilized;

[0173] Interval 3: (2.5 <M1≤3.5),

[0174] Description of technical effect:

[0175] In the third interval, the graded energy dissipation differentiation index M1 is at a high level, indicating that the seismic performance of the bridge under daily loads and environmental changes is good, but there is still room for optimization. Technically, the bridge structure needs to be optimized and improved to further improve its seismic performance; the overall performance of the bridge can be improved by further optimizing the structural design of the piers and tie beams; if changes in ambient temperature or load conditions are expected to cause a 1% decrease in the M1 value, u1 is increased by at least 3% accordingly; the purpose of this pre-adjustment strategy is to respond to adverse conditions in advance and ensure that the performance of the energy dissipation section can always meet or exceed the design requirements; specific measures include slightly increasing the concrete strength fc and the steel yield strength fy; when M1 is close to 3.5, the concrete strength and steel yield strength are increased by 5% and 3% respectively, and the strain monitoring frequency of the piers and tie beams is increased;

[0176] Judging criteria and rules:

[0177] In order to ensure the stability of the bridge within this interval, the M1 threshold value is set to 3.0. When the M1 value is lower than 3.0, the following measures need to be taken: If M1≤3.0, the piers and tie beams are slightly reinforced and the monitoring frequency is increased. The specific measures include increasing the concrete strength by 3% and the steel yield strength by 2%. If M1>3.0, routine inspections are carried out to maintain the current structural state and regularly monitor the structural strain and displacement.

[0178] Interaction rules and value changes:

[0179] In this range, the ambient temperature T and the concrete internal temperature T int , vehicle axle weight W axle 、Traffic flow N veh, vehicle speed V veh , daily average traffic load L day , peak traffic load L peak , pier strain ò pier , tie beam strain ò beam and bridge displacement D bridge The impacts of the changes of all of them on M1 need to be considered. If the ambient temperature and the internal temperature of the concrete increase by 10% respectively, the classification energy dissipation discrimination index will decrease by 2%; if the vehicle axle load, traffic volume and vehicle speed increase by 7% respectively, then M1 will increase by 5%; if the daily average traffic load and the peak traffic load increase by 10% respectively, M1 will increase by 7%; if the pier strain and the tie beam strain decrease by 5% respectively, M1 will decrease by 3%; if the bridge displacement increases by 10%, M1 will increase by 5%; these interaction rules ensure the dynamic adjustment and optimization among parameters, and improve the seismic performance of the bridge under different load and environmental conditions;

[0180] Interval Four: (3.5 < M1 < 5). In the fourth interval, the classification energy dissipation discrimination index M1 is at the highest level, indicating that the seismic performance of the bridge under daily loads and environmental changes is very good, and the design achieves the expected classification energy dissipation effect; technically, it is necessary to maintain and monitor the bridge structure to ensure its long-term stability; adjust the u1 value by 2% to ensure that the shear strength V h of the energy dissipation section continues to remain above the optimized level; specific measures include maintaining the current concrete strength fc and the yield strength fy of the steel bars, and maintaining the existing monitoring frequency. By regularly detecting and monitoring the strains and displacements of the piers and tie beams, ensure that the seismic performance of the bridge remains good continuously;

[0181] Judgment criteria and rules:

[0182] To ensure the stability of the bridge in this interval, set the M1 threshold value in this interval = 4.0. When the M1 value is lower than 4.0, the following measures need to be taken: if M1 ≤ 4.0, conduct routine inspections on the piers and tie beams, and increase the monitoring frequency by 3%. Specific measures include regularly detecting the concrete strength and the yield strength of the steel bars; if M1 > 4.0, conduct routine inspections, maintain the current structural state, and regularly monitor the structural strains and displacements;

[0183] Interaction rules and numerical changes:

[0184] In this interval, the ambient temperature T, the internal temperature T int of the concrete, the vehicle axle load W axle , traffic volume N veh , vehicle speed V veh , daily average traffic load L day , peak traffic load L peak , pier strain ò pier , tie beam strain òbeam and bridge displacement D bridge The impact of changes in M1 must be considered; if the ambient temperature and the internal temperature of the concrete increase by 10% respectively, the graded energy consumption differentiation index will decrease by 1%; if the vehicle axle weight, traffic volume and vehicle speed increase by 5% respectively, (M1) will increase by 3%; if the average daily traffic load and peak traffic load increase by 5% respectively, M1 will increase by 4%; if the pier strain and tie beam strain decrease by 3% respectively, M1 will decrease by 2%; if the bridge displacement increases by 5%, M1 will increase by 3%; these interaction rules ensure dynamic adjustment and optimization among various parameters, so that the seismic performance of the bridge under different loads and environmental conditions can be maintained; if the long-term climate model prediction shows that large temperature fluctuations will affect the performance of the bridge, even if the M1 value decreases by 1%, it is recommended to slightly increase u1 by 2% to ensure V h Able to accommodate possible future increases in loads; such adjustments ensure that the bridge maintains its excellent seismic performance in the face of future challenges.

[0185] Embodiment five:

[0186] Further explanation based on the fourth embodiment, this embodiment takes into account the quantifiable parameters A of the bridge under different temperatures and vehicle loads, and performs detailed analysis and processing on these parameters to construct a graded energy consumption differentiation index M1, and accordingly, V h >u1×V cs The u1 in is adjusted dynamically.

[0187] During the experimental preparation, the quantifiable parameters A that need to be collected were first determined, including the ambient temperature T and the internal temperature of the concrete. In the fourth interval, the graded energy dissipation differentiation index M1 is at the highest level, indicating that the seismic performance of the bridge under daily loads and environmental changes is very good, and the design has achieved the expected graded energy dissipation effect; technically, the bridge structure needs to be maintained and monitored to ensure its long-term stability; the u1 value is adjusted by 2% to ensure the shear strength V of the energy dissipation section h Continue to maintain above the optimization level; vehicle axle weight W axle 、Traffic flow N veh , vehicle speed V veh , daily average traffic load L day , peak traffic load L peak 、Pier strain pier , tie beam strain beam and bridge displacement D bridge ; These parameters are collected in real time by on-site monitoring equipment, and the sampling frequency is set to once an hour. The continuous monitoring lasts for one month, with a total of N3 = 720 samples;

[0188] Using the above data, the average, maximum and minimum values ​​of each parameter were calculated, and the calculation formula of the graded energy consumption differentiation index M1 was used. In this process, special attention was paid to the analysis of the M1 values ​​in different intervals to evaluate the seismic performance of the bridge in its current state, and u1 was dynamically adjusted according to the changing trend of the M1 value.

[0189] For example, when it is predicted that the ambient temperature will increase significantly, the model predicts the potential impact of this change on the M1 value, and accordingly adjusts the u1 value in advance to ensure the shear strength V h Compared with the shear bearing capacity of ordinary concrete tie beam V cs Maintain sufficient gaps between them to accommodate the expected increased loads;

[0190] In addition, for the specific values ​​of M1 in each interval, corresponding technical measures are taken, such as increasing the concrete strength fc and the steel yield strength fy, and improving the u1 value, to optimize the seismic performance of the bridge. All these measures are aimed at ensuring the stability and safety of the bridge under various load and environmental conditions;

[0191] The following is the representation of experimental data and calculation results in Excel:

[0192] Table 1

[0193]

[0194] The table analysis is as follows:

[0195] The invention has the advantages of creativity and novelty. The embodiment successfully realizes the shear strength V of the energy consumption section by dynamically adjusting the graded energy consumption differentiation index M1. h Relative to the shear bearing capacity of ordinary concrete tie beam V cs This process not only demonstrates a new method to consider the influence of daily loads such as ambient temperature and traffic volume, but also ensures that the seismic performance of the bridge under different conditions is always kept in the best state through real-time adjustment of the M1 value.

[0196] The relationship between numerical changes and their impact: According to the table data, as the ambient temperature T and the internal temperature of concrete T int , vehicle axle weight T int With the increase of parameters such as load, the M1 value shows an upward trend; this means that in a more severe environment or under a greater load, by adjusting the u1 value, the seismic performance of the bridge can be effectively improved to ensure its safety and stability;

[0197] From the data of experimental bridges A to E, it can be observed that with the increase of ambient temperature and internal temperature of concrete, the M1 value of the bridge gradually increases, indicating that the energy dissipation capacity of the bridge needs to be further strengthened to adapt to higher temperature changes; by reasonably adjusting the design of the energy dissipation section, such as increasing the u1 value, ensuring the shear strength V h With V cs The ratio between them is kept at an optimal level, thereby improving the overall seismic performance of the bridge;

[0198] In the range of M1 values ​​close to 1.5 to 2.5, i.e., in the case of experimental bridges A and B, the shear strength V of the energy dissipation section is ensured by increasing the u1 value by 10%. h Within the ideal range, it effectively responds to daily loads and environmental changes, showing a significant improvement in seismic performance; this adjustment strategy demonstrates the creativity and novelty of the invention in practical applications, and provides a new idea for bridge design;

[0199] When the M1 value is close to 3.0, such as the experimental bridge E, a more subtle adjustment, such as increasing the u1 value by 2%, can ensure the shear strength V of the energy dissipation section. h Continue to maintain above the optimization level, which shows that the invention content can be flexibly adjusted according to actual conditions to achieve the best energy consumption effect;

[0200] The dynamic adjustment strategy in this embodiment can achieve real-time optimization of the seismic performance of the bridge by adjusting the design parameter u1 of the energy dissipation section under different environmental and load conditions; this method not only improves the flexibility and adaptability of bridge design, but also effectively reduces maintenance costs while improving safety;

[0201] In summary, tabular data and analysis have significant advantages in achieving dynamic optimization of bridge seismic performance; this dynamic adjustment mechanism based on the M1 value can not only ensure the stability and safety of the bridge under various conditions, but also can be flexibly adjusted according to actual conditions, demonstrating a new method of bridge design and maintenance.

[0202] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

[0203] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0204] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0205] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0206] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A design method for a replaceable energy-absorbing tie beam for improving the seismic performance of a double-column pier of a bridge, characterized in that: The specific steps include: Step S1: Collect the dimensional data of the bridge pier and the ordinary concrete tie beam, and determine the shear bearing capacity V of the ordinary concrete tie beam by calculation. cs ; Step S2: Obtain the shear bearing capacity V calculated in step S1 cs , and set the shear strength of the tie beam energy absorption section to V h ; Step S3: Using the finite element analysis model, the shear bearing capacity V of the ordinary reinforced concrete tie beam is cs Shear strength V of energy dissipation section h Perform verification and set u1 as the preset coefficient to ensure V h Does not exceed the preset coefficient u1 and V cs Product, if V h >u1×V cs , then re-design the energy consumption section matching; Step S4: obtaining quantifiable parameters A of the bridge pier under the effects of temperature and daily vehicle load, and performing analysis and processing to construct a graded energy consumption differentiation index M1, which is used to dynamically adjust u1; and the quantifiable parameters A include temperature parameters, vehicle load parameters, daily load parameters, structural parameters and material parameters; The temperature parameters include the ambient temperature and the temperature inside the concrete; the ambient temperature parameter and the concrete temperature parameter are marked as WDc1 and WDc2 respectively; The vehicle load parameters include vehicle axle weight Waxle, vehicle flow Nveh, and vehicle speed Vveh; and the vehicle load parameters are marked as QCZh; the calculation formula is as follows: Waxle,j is the vehicle axle weight in the jth period, which is the axle weight of vehicles passing through the bridge per unit time; Nveh,j is the traffic volume in the jth period, which is the number of vehicles passing through the bridge per unit time; Vveh,j is the vehicle speed in the jth period, which is the speed at which vehicles pass through the bridge; M is the total number of periods; The daily load parameters include the average daily traffic load Lday, the peak traffic load Lpeak and the dynamic load coefficient DLC; The daily load parameter is marked as RCHz, and the calculation formula is as follows: Lday is the total vehicle load passing through the bridge in one day; Lpeak is the maximum vehicle load in the current time period; DLC is the load magnification factor caused by the dynamic load of the vehicle; Lstatic is the static load of the vehicle; The structural parameters include pier strain òpier, tie beam strain òbeam, and bridge displacement Dbridge; The average value function of the structure's own parameters is marked as JGc, and the calculation formula is as follows: òpier is the strain of the pier under daily load; òbeam is the strain of the tie beam under daily load; Dbridge is the displacement of the bridge under load; The material parameters include concrete strength fc and steel bar yield strength fy; The normalized formula for the material parameters is marked as CLs, and the calculation formula is as follows: fc is the compressive strength of concrete actually used; fy is the yield strength of steel bars; k is a constant used to normalize material parameters; The calculation formula of the graded energy consumption differentiation index M1 is defined as follows: Parameter explanation: M1 is the graded energy consumption differentiation index; N3 is the sampling times of ambient temperature and concrete internal temperature; The value range of the graded energy consumption differentiation index M1 is set to (0.5, 5). When the M1 value is close to 0.5, it indicates that the seismic performance of the bridge under daily loads and environmental changes is poor and needs to be further strengthened; when the M1 value is close to 5, it indicates that the seismic performance of the bridge under various loads and environmental changes is good, and the design has achieved the expected graded energy consumption effect; Step S5: obtaining a calculation formula for the slenderness ratio of the replaceable energy-absorbing tie beam to perform matching design of the energy-absorbing section; Step S6: Set the width-to-thickness ratio of the energy-absorbing section flange to a limited value Within, where f y′ is the yield strength of the flange material. If the width-to-thickness ratio of the energy-absorbing section flange exceeds the limit value Then re-design the energy consumption section matching; Step S7: limiting the design width of the connection section to 0.6D-0.8D and the height to 0.8D-1.0D, where D is the diameter of the pier; Step S8: Set the energy dissipation section stiffness K h and the connection segment stiffness K l The ratio is limited to 0.1 to 0.25, and graded energy consumption is judged; Step S9: Obtain the plastic shear bearing capacity V of the connection segment lp and plastic bending capacity M lp It is limited to Mlp≥0.5lΩVh, Vlp≥ΩVh, where l is the clear span of the tie beam and Ω is the overstrength coefficient; Step S10: Conduct a comprehensive seismic performance assessment of the double-column pier structure of the bridge through a finite element analysis model.

2. The design method of a replaceable energy-dissipating cross beam for improving the seismic performance of a double-column pier of a bridge according to claim 1, characterized in that: The value range (0.5, 5) of the hierarchical energy-dissipation discrimination index M1 is divided into four intervals, and each interval is described in detail; Interval 1 (0.5 < M1 ≤ 1.5). Within this interval, the grading energy consumption discrimination index M1 is relatively low, indicating that the seismic performance of the bridge under daily loads and environmental changes is poor and further strengthening is required. Technically, it is necessary to enhance the bridge structure to improve its seismic performance. By increasing the structural strength of at least 10% of the piers and crossbeams, the overall seismic capacity of the bridge can be effectively improved; u1 is increased by at least 25% to ensure the shear strength V of the energy dissipation section h and the shear bearing capacity V of the ordinary concrete crossbeam cs There is a sufficient gap between them; Interval two (1.5 < M1 ≤ 2.5), the hierarchical energy-dissipation discrimination index M1 is at a medium level, indicating that the seismic performance of the bridge under daily loads and environmental changes is relatively stable, but there is still room for improvement; Technically, it is necessary to regularly maintain and optimize the bridge structure to improve its seismic performance; by optimizing the structural design of the piers and cross beams, further improve the overall performance of the bridge; increase u1 by 10% to strengthen the response of the energy-dissipation section; Interval three (2.5 < M1 ≤ 3.5), within the third interval, the hierarchical energy-dissipation discrimination index M1 is at a relatively high level, indicating that the seismic performance of the bridge under daily loads and environmental changes is good, but there is still room for optimization. Technically, it is necessary to optimize and improve the bridge structure by less than 5% to further improve its seismic performance; by further optimizing the structural design of the piers and cross beams, improve the overall performance of the bridge; if it is predicted that the change in environmental temperature or load conditions will cause the value of M1 to decrease by 1%, then make a corresponding increase in u1 of at least 3%; Interval four (3.5 < M1 < 5), within the fourth interval, the hierarchical energy-dissipation discrimination index M1 is at the highest level, indicating that the seismic performance of the bridge under daily loads and environmental changes is very good, and the design has achieved the expected hierarchical energy-dissipation effect; Technically, it is necessary to maintain and monitor the bridge structure to ensure its long-term stability; Adjust u1 value by 2% to ensure the shear strength V of the energy dissipation section h Continue to stay above the optimization level.

3. The design method of replaceable energy-absorbing tie beam for improving the seismic performance of double-column piers of bridges according to claim 1 is characterized in that: The slenderness ratio calculation formula is: Where e is the length of the energy consumption section, M P is the bending bearing capacity, V P is the shear bearing capacity; if or When the energy dissipation section undergoes bending-shear coupling yield and bending yield, the matching design of the energy dissipation section needs to be redesigned, that is, the length of the energy dissipation section is adjusted according to Δ0.1e and then recalculated. When , shear yield occurs in the energy dissipation section, meeting the design requirements.

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