A method for evaluating the seismic performance of rural highway bridges

Abstract

The invention relates to the field of bridge seismic performance evaluation, and specifically discloses a method for evaluating the seismic performance of a rural highway bridge. The invention obtains geometric characteristics, material properties, structural details and boundary conditions of the rural highway bridge to be built, and uses computer-aided design software and finite element analysis software to establish a digital model of the rural highway bridge to be built; according to an earthquake prediction model and earthquake historical records of the area where the rural highway bridge to be built is located, the earthquake risk of the area where the rural highway bridge to be built is evaluated, and a suitable seismic wave is selected as input, so that the seismic performance of the designed bridge is compatible with the actual seismic demand of the bridge; the response information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load is obtained, and the seismic performance of the rural highway bridge to be built is evaluated, so that the seismic performance evaluation result of the bridge is more reliable and accurate, and the overall stability and safety of the bridge are guaranteed.

Description

Technical Field

[0001] The invention relates to the field of bridge seismic performance evaluation, and in particular to a rural highway bridge seismic performance evaluation method. Background Art

[0002] Earthquakes are a natural risk that can cause catastrophic damage to bridges. Testing the seismic performance of bridges during the design phase can ensure that the bridge can withstand the expected earthquake intensity and reduce losses when an earthquake occurs. It can also help the design team identify weak points in the bridge structure and optimize the overall seismic performance of the bridge by adjusting design parameters, selecting more suitable materials or adding seismic components.

[0003] Therefore, the importance of testing the seismic performance of bridges during their design phase cannot be ignored, as it is related to the structural safety of the bridge, public safety, and the stability of the entire transportation network.

[0004] Existing methods for testing the seismic performance of bridges during the bridge design phase mainly use numerical simulation technology, such as finite element analysis, to simulate the seismic response of the bridge, predict the response of the bridge under earthquakes of different intensities, and verify its seismic resistance. This method has the following shortcomings: On the one hand, the existing method does not quantitatively analyze the seismic load applied to the bridge in the seismic response simulation and select appropriate seismic waves as input based on the historical and predicted earthquake conditions in the area where the bridge is located. Instead, it defaults to a set value or applies different levels of seismic loads in sequence, which may cause the seismic performance of the final designed bridge to be higher than the actual seismic requirement of the bridge or lower than the actual seismic requirement of the bridge, thereby causing material waste, increased costs, or substandard stability and safety of the bridge structure, and posing safety hazards.

[0005] On the other hand, when evaluating the results of seismic response simulation of bridges, the existing methods have relatively simple evaluation indicators, mostly focusing on basic indicators such as displacement and deformation, without monitoring the internal force of the bridge structure. As a result, the reliability and accuracy of the seismic performance evaluation results of the bridge are low, and the overall stability and safety of the bridge cannot be guaranteed. Summary of the invention

[0006] In view of the above problems, the present invention proposes a method for evaluating the seismic performance of rural road bridges. The specific technical scheme is as follows: A method for evaluating the seismic performance of rural road bridges, comprising the following steps: Step 1, establishing a digital model of the bridge: through the design drawings of the rural road bridge to be built and the field survey of the area where the rural road bridge to be built is located, the geometric characteristic information, material property information, structural detail information and boundary condition information of the rural road bridge to be built are obtained, and the digital model of the rural road bridge to be built is established using computer-aided design software and finite element analysis software.

[0007] Step 2. Earthquake hazard assessment of the area where the bridge is located: Obtain the earthquake prediction model of the area where the rural highway bridge is to be built through the earthquake zoning map of the area where the rural highway bridge is to be built, and obtain the earthquake historical records of the area where the rural highway bridge is to be built, and assess the comprehensive earthquake hazard index of the area where the rural highway bridge is to be built.

[0008] Step 3. Acquisition and input of suitable seismic loads for bridges: According to the comprehensive seismic hazard index of the area where the rural highway bridge to be built is located, the suitable seismic loads for the rural highway bridge to be built are analyzed and input into the digital model of the rural highway bridge to be built.

[0009] Step 4. Obtaining bridge response under seismic load: Obtain the response information of each component in the digital model of the rural highway bridge to be built under seismic load, where the response information includes deformation information, vibration information, internal force information and damage information.

[0010] Step 5. Comprehensive evaluation and feedback on the seismic performance of the bridge: Based on the response information of each component in the digital model of the rural highway bridge to be built under the action of seismic load, comprehensively evaluate the seismic performance index of the rural highway bridge to be built, determine whether the seismic performance of the rural highway bridge to be built meets the requirements, and provide feedback.

[0011] On the basis of the above embodiment, the specific analysis process of step 2 includes: S1: obtaining a seismic zoning map of the area where the rural highway bridge is to be built from the seismic organization of the area where the rural highway bridge is to be built.

[0012] The latitude and longitude coordinates of the rural road bridge to be built are obtained, and the specific geographical location of the rural road bridge to be built is marked on the earthquake zoning map of the area where the rural road bridge to be built is located.

[0013] According to the specific geographical location of the rural road bridge to be built, the predicted earthquake parameters of the location point are read on the seismic zoning map to obtain the predicted seismic activity information of the area where the rural road bridge to be built is located, wherein the seismic activity information includes the time distribution of earthquakes, the spatial distribution of earthquakes, the frequency of earthquakes and the intensity of earthquakes, and an earthquake prediction model is constructed for the area where the rural road bridge to be built is located.

[0014] S2: Extract the historical earthquake records stored in the database for the area where the rural highway bridge is to be built, and obtain the seismic wave data of each historical earthquake in the area where the rural highway bridge is to be built, wherein the seismic wave data includes the amplitude, frequency and duration of the seismic wave.

[0015] On the basis of the above embodiment, the specific analysis process of step two also includes: D1: extracting the influencing factors corresponding to the time distribution of each earthquake and the spatial distribution of each earthquake stored in the database, and according to the predicted time distribution of earthquakes and the spatial distribution of earthquakes in the area where the rural highway bridge is to be built, respectively screen out the influencing factors corresponding to the predicted time distribution of earthquakes and the spatial distribution of earthquakes in the area where the rural highway bridge is to be built, and record them as δ1 and δ2 respectively.

[0016] The predicted earthquake frequency and earthquake intensity in the area where the rural highway bridge is to be built are denoted as h and p respectively.

[0017] By analyzing the formula Get the expected earthquake risk factor φ of the area where the rural highway bridge is to be built 预期 , where h0 and p0 represent the preset thresholds of earthquake frequency and earthquake intensity respectively, a1 and a2 represent the preset weights of earthquake frequency and earthquake intensity respectively, and a1+a2=1.

[0018] D2: The amplitude, frequency and duration of each historical earthquake in the area where the rural highway bridge is to be built are recorded as b x 、f x ,t x , x represents the number of the xth earthquake in history, x=1,2,...,y.

[0019] By analyzing the formula Get the historical earthquake risk factor φ of the area where the rural highway bridge is to be built 历史 , where b0, f0, t0 represent the thresholds of the amplitude, frequency and duration of the preset seismic wave, respectively, c1, c2, c3 represent the weights of the amplitude, frequency and duration of the preset seismic wave, respectively, and c1+c2+c3=1.

[0020] D3: Calculate the weighted average of the expected earthquake risk factor and the historical earthquake risk factor in the area where the rural highway bridge is to be built, and obtain the comprehensive earthquake risk index in the area where the rural highway bridge is to be built.

[0021] On the basis of the above embodiment, the specific analysis process of step three is: extract the basic information of simulated seismic wave force corresponding to each range of comprehensive earthquake hazard index stored in the database, wherein the basic information includes direction, intensity, frequency, and duration; according to the comprehensive earthquake hazard index of the area where the rural road bridge is to be built, screen and obtain the basic information of simulated seismic wave force corresponding to the comprehensive earthquake hazard index of the area where the rural road bridge is to be built, and record it as the basic information of simulated seismic wave force suitable for the rural road bridge to be built, thereby obtaining the suitable seismic load for the rural road bridge to be built, and inputting it into the digital model of the rural road bridge to be built.

[0022] On the basis of the above embodiment, the specific analysis process of step five includes: according to the deformation information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the maximum displacement, maximum rotation angle and maximum deflection of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained, and they are respectively recorded as l i ,θ i , τ i , i represents the number of the i-th component in the digital model of the rural highway bridge to be built, i = 1, 2, ..., n.

[0023] By analyzing the formula The deformation coefficient ψ1 of the rural highway bridge to be built under the action of earthquake load is obtained, where l0, θ0, τ0 represent the threshold values ​​of the maximum displacement, maximum rotation angle and maximum deflection of the preset bridge components, β l-i , β′ θ-i , β″ τ-i They respectively represent the displacement influence weight, rotation influence weight and deflection influence weight of the i-th component in the preset digital model of the rural highway bridge to be built,

[0024] On the basis of the above embodiment, the specific analysis process of step 5 further includes: according to the vibration information of each component in the digital model of the rural highway bridge to be built under the earthquake load, the vibration amplitude and frequency of each component in the digital model of the rural highway bridge to be built under the earthquake load are obtained, which are respectively recorded as B i 、F i .

[0025] By analyzing the formula The vibration coefficient ψ2 of the rural highway bridge to be built under the action of earthquake load is obtained, where B0 and F0 represent the threshold values ​​of the vibration amplitude and frequency of the preset bridge components respectively.

[0026] On the basis of the above embodiment, the specific analysis process of step 5 further includes: according to the internal force information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the values ​​of various internal forces of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained, which are recorded as g iu , u represents the number of the u-th internal force, u=1,2,...,v.

[0027] Extract the expected values ​​of various internal forces of each component in the digital model of the rural highway bridge to be built stored in the database and record them as

[0028] By analyzing the formula The internal force compliance coefficient of the rural highway bridge to be built under the action of earthquake load is obtained as ψ3, where e represents the natural constant, △g iu It represents the deviation threshold of the u-th internal force of the ith component in the digital model of the rural highway bridge to be built under the preset seismic load.

[0029] On the basis of the above embodiment, the specific analysis process of step five also includes: according to the damage information of each component in the digital model of the rural road bridge to be built under the action of seismic load, obtaining the length and position of each crack in each component in the digital model of the rural road bridge to be built under the action of seismic load, as well as the area and position of each damage.

[0030] The crack influence factor and damage influence factor of each area of ​​each component of the rural highway bridge to be built are set. According to the location of each crack and the location of each damage in each component of the digital model of the rural highway bridge to be built under the action of seismic load, the crack influence factor of each crack area in each component of the digital model of the rural highway bridge to be built under the action of seismic load and the damage influence factor of each damage area are screened and recorded as ε ij , j represents the number of the j-th crack, j=1, 2, ..., m, and j′ represents the number of the j′-th damage, j′=1, 2, ..., m′.

[0031] By analyzing the formula The damage coefficient ψ4 of the rural highway bridge to be built under earthquake load is obtained, where r ij 、z ij′ They represent the length of the jth crack in the i-th component and the damaged area at the j′th location in the digital model of the rural highway bridge to be built under earthquake load, respectively, and η △r , κ △z They respectively represent the influence factors corresponding to the preset unit crack length and unit damage area.

[0032] On the basis of the above embodiment, the specific analysis process of step 5 also includes: substituting the deformation coefficient ψ1, vibration coefficient ψ2, internal force compliance coefficient ψ3 and damage coefficient ψ4 of the rural road bridge to be built under the earthquake load into the analysis formula The seismic performance index ξ of the rural highway bridge to be built is obtained, where σ1, σ2, σ3, and σ4 represent the weights of the preset deformation coefficient, vibration coefficient, internal force compliance coefficient, and damage coefficient, respectively, and σ1+σ2+σ3+σ4=1.

[0033] On the basis of the above embodiment, the specific analysis process of step five also includes: comparing the seismic performance index of the rural road bridge to be built with a preset seismic performance index warning value; if the seismic performance index of the rural road bridge to be built is greater than or equal to the preset seismic performance index warning value, the seismic performance of the rural road bridge to be built meets the requirements; otherwise, the seismic performance of the rural road bridge to be built does not meet the requirements, and the feedback is given to the design team of the rural road bridge to be built.

[0034] Compared with the prior art, the rural highway bridge seismic performance assessment method described in the present invention has the following beneficial effects: 1. The present invention quantitatively analyzes the seismic load simulated by the seismic response of the bridge based on the historical and predicted earthquake conditions in the area where the bridge is located, and selects appropriate seismic waves as input, so that the seismic performance of the designed bridge is compatible with the actual seismic requirements of the bridge, avoiding material waste and increased costs, while ensuring the safety of the bridge structure.

[0035] 2. When evaluating the results of the bridge seismic response simulation, the present invention analyzes the responses of various parts of the bridge in various dimensions, such as deformation, vibration, damage and internal force, thereby improving the reliability and accuracy of the evaluation results of the bridge's seismic performance, ensuring the overall stability and safety of the bridge, and is also conducive to identifying potential weak links in the bridge, providing reference opinions for the design team, so that the bridge meets the requirements of the seismic design specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0037] Figure 1 It is a schematic diagram of the method flow of the present invention. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] See also Figure 1 As shown, a method for evaluating the seismic performance of a rural highway bridge provided by the present invention comprises the following steps: Step 1, establishing a digital model of the bridge: obtaining geometric characteristic information, material property information, structural detail information and boundary condition information of the rural highway bridge to be built through the design drawings of the rural highway bridge to be built and the field survey of the area where the rural highway bridge to be built is located, and establishing a digital model of the rural highway bridge to be built using computer-aided design software and finite element analysis software.

[0040] It should be noted that the geometric characteristic information of the rural road bridge to be built includes bridge type, overall bridge dimension information, pier information, beam information and support information, among which the overall bridge dimension information includes total length, span, width, height, etc., the pier information includes the position, height, cross-sectional size and shape of each pier, the beam information includes the type, length, cross-sectional size and shape of each beam, and the support information includes the type and position of each support.

[0041] In a specific embodiment, the bridge types include beam bridges, arch bridges, suspension bridges, cable-stayed bridges, etc.

[0042] In a specific embodiment, the types of beams include continuous beams, simply supported beams, and the like.

[0043] In a specific embodiment, the types of supports include fixed supports, movable supports, hinge points, etc.

[0044] It should be noted that the material property information of the rural road bridges to be built includes the elastic modulus, Poisson's ratio, yield strength, tensile strength, density of steel, concrete, prestressed concrete, wood, composite materials and stone, as well as the physical and mechanical properties of the soil, such as shear modulus and damping ratio.

[0045] It should be noted that the elastic modulus is used to measure the ability of a material to resist deformation within the elastic range.

[0046] It should be noted that Poisson's ratio is used to describe the proportional relationship between the lateral strain and the longitudinal strain of a material.

[0047] It should be noted that yield strength refers to the stress point at which the material begins to deform plastically.

[0048] It should be noted that tensile strength refers to the maximum stress that a material can withstand before breaking.

[0049] It should be noted that the structural detail information of the rural highway bridges to be built includes detailed features, such as piers, abutments, expansion joints, bridge decks, crash barriers, etc., as well as connection details, such as welding, bolted connections, cast connections, prestressed tendons, etc., and also includes seismic design, such as isolation layers, damper types and parameters, as well as the design and application of prestressed systems.

[0050] It should be noted that the boundary condition information of the rural highway bridge to be built includes constraint information, temperature effect information and foundation condition information, among which the constraint information includes fixed end, free end, rolling bearing, spring bearing, etc. The temperature effect information is the influence of thermal expansion and contraction on the structure, and the foundation condition information includes soil type, groundwater level, geological structure information, etc.

[0051] It should be noted that soil types include but are not limited to: hard rock, hard soil, medium-soft soil, soft soil, etc.

[0052] Step 2. Earthquake hazard assessment of the area where the bridge is located: Obtain the earthquake prediction model of the area where the rural highway bridge is to be built through the earthquake zoning map of the area where the rural highway bridge is to be built, and obtain the earthquake historical records of the area where the rural highway bridge is to be built, and assess the comprehensive earthquake hazard index of the area where the rural highway bridge is to be built.

[0053] As a preferred solution, the specific analysis process of step 2 includes: S1: obtaining a seismic zoning map of the area where the rural highway bridge is to be built from the seismic agency of the area where the rural highway bridge is to be built.

[0054] In another specific embodiment, the latest earthquake zoning map of the area where the rural highway bridge is to be built is obtained through the Geological Survey Bureau.

[0055] It should be noted that earthquake zoning maps are maps that predict the intensity and frequency of earthquakes that a region may suffer in the future based on historical earthquake records, geological structures and seismological research results. These maps usually use parameters such as peak ground acceleration, response spectrum or ground motion displacement to indicate the impact of earthquakes.

[0056] The latitude and longitude coordinates of the rural road bridge to be built are obtained, and the specific geographical location of the rural road bridge to be built is marked on the earthquake zoning map of the area where the rural road bridge to be built is located.

[0057] According to the specific geographical location of the rural road bridge to be built, the predicted earthquake parameters of the location point are read on the seismic zoning map to obtain the predicted seismic activity information of the area where the rural road bridge to be built is located, wherein the seismic activity information includes the time distribution of earthquakes, the spatial distribution of earthquakes, the frequency of earthquakes and the intensity of earthquakes, and an earthquake prediction model is constructed for the area where the rural road bridge to be built is located.

[0058] It should be noted that seismic activity refers to the characteristics of earthquakes occurring in a specific area and a specific time period.

[0059] It should be noted that the temporal distribution of earthquakes refers to the temporal pattern of earthquake occurrence, such as whether there is a periodic activity cycle, or whether they are more frequent in certain periods.

[0060] It should be noted that the spatial distribution of earthquakes refers to the geographical distribution of earthquakes, which is usually related to plate boundaries, fault lines or other geological structures.

[0061] It should be noted that earthquake frequency refers to the number of earthquakes occurring per unit time within a specific period of time, which can be used to describe the activity level of earthquake activity.

[0062] It should be noted that earthquake intensity refers to the magnitude of an earthquake, which reflects the amount of energy released by the earthquake. Magnitude is usually expressed in Richter magnitude or moment magnitude.

[0063] S2: Extract the historical earthquake records stored in the database for the area where the rural highway bridge is to be built, and obtain the seismic wave data of each historical earthquake in the area where the rural highway bridge is to be built, wherein the seismic wave data includes the amplitude, frequency and duration of the seismic wave.

[0064] As a preferred solution, the specific analysis process of step 2 also includes: D1: extracting the influencing factors corresponding to the time distribution of each earthquake and the spatial distribution of each earthquake stored in the database, and according to the predicted time distribution of earthquakes and the spatial distribution of earthquakes in the area where the rural highway bridge is to be built, respectively screening and obtaining the influencing factors corresponding to the predicted time distribution of earthquakes and the spatial distribution of earthquakes in the area where the rural highway bridge is to be built, and recording them as δ1 and δ2 respectively.

[0065] The predicted earthquake frequency and earthquake intensity in the area where the rural highway bridge is to be built are denoted as h and p respectively.

[0066] By analyzing the formula Get the expected earthquake risk factor φ of the area where the rural highway bridge is to be built 预期 , where h0 and p0 represent the preset thresholds of earthquake frequency and earthquake intensity respectively, a1 and a2 represent the preset weights of earthquake frequency and earthquake intensity respectively, and a1+a2=1.

[0067] D2: The amplitude, frequency and duration of each historical earthquake in the area where the rural highway bridge is to be built are recorded as b x 、f x ,t x , x represents the number of the xth earthquake in history, x=1,2,...,y.

[0068] By analyzing the formula Get the historical earthquake risk factor φ of the area where the rural highway bridge is to be built 历史 , where b0, f0, t0 represent the thresholds of the amplitude, frequency and duration of the preset seismic wave, respectively, c1, c2, c3 represent the weights of the amplitude, frequency and duration of the preset seismic wave, respectively, and c1+c2+c3=1.

[0069] D3: Calculate the weighted average of the expected earthquake risk factor and the historical earthquake risk factor in the area where the rural highway bridge is to be built, and obtain the comprehensive earthquake risk index in the area where the rural highway bridge is to be built.

[0070] It should be noted that the weights of the expected earthquake risk factor and the historical earthquake risk factor are set values, and the cumulative sum is 1.

[0071] Step 3. Acquisition and input of suitable seismic loads for bridges: According to the comprehensive seismic hazard index of the area where the rural highway bridge to be built is located, the suitable seismic loads for the rural highway bridge to be built are analyzed and input into the digital model of the rural highway bridge to be built.

[0072] As a preferred solution, the specific analysis process of step three is: extracting the basic information of simulated seismic wave forces corresponding to the range of each comprehensive earthquake hazard index stored in the database, wherein the basic information includes direction, intensity, frequency, and duration; based on the comprehensive earthquake hazard index of the area where the rural road bridge is to be built, screening out the basic information of simulated seismic wave forces corresponding to the comprehensive earthquake hazard index of the area where the rural road bridge is to be built, recording it as the basic information of simulated seismic wave forces suitable for the rural road bridge to be built, and then obtaining the suitable seismic load for the rural road bridge to be built, and inputting it into the digital model of the rural road bridge to be built.

[0073] It should be noted that the directions of the simulated seismic wave force can be multiple.

[0074] In this embodiment, the present invention quantitatively analyzes the seismic load simulated by the seismic response of the bridge and selects appropriate seismic waves as input based on the historical and predicted earthquake conditions in the area where the bridge is located, so that the seismic performance of the designed bridge is compatible with the actual seismic requirements of the bridge, avoiding material waste and increased costs, while ensuring the safety of the bridge structure.

[0075] Step 4. Obtaining bridge response under seismic load: Obtain the response information of each component in the digital model of the rural highway bridge to be built under seismic load, where the response information includes deformation information, vibration information, internal force information and damage information.

[0076] In a specific embodiment, the components of the rural highway bridge to be constructed include but are not limited to: piers, abutments, main beams, connectors and supports, etc.

[0077] In another specific embodiment, the components of the rural road bridge to be constructed are also referred to as components or structures.

[0078] Step 5. Comprehensive evaluation and feedback on the seismic performance of the bridge: Based on the response information of each component in the digital model of the rural highway bridge to be built under the action of seismic load, comprehensively evaluate the seismic performance index of the rural highway bridge to be built, determine whether the seismic performance of the rural highway bridge to be built meets the requirements, and provide feedback.

[0079] As a preferred solution, the specific analysis process of step 5 includes: according to the deformation information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the maximum displacement, maximum rotation angle and maximum deflection of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained, and they are respectively recorded as l i ,θ i , τ i , i represents the number of the i-th component in the digital model of the rural highway bridge to be built, i = 1, 2, ..., n.

[0080] By analyzing the formula The deformation coefficient ψ1 of the rural highway bridge to be built under the action of earthquake load is obtained, where l0, θ0, τ0 represent the threshold values ​​of the maximum displacement, maximum rotation angle and maximum deflection of the preset bridge components, β l-i , β′ θ-i , β″ τ-i They respectively represent the displacement influence weight, rotation influence weight and deflection influence weight of the i-th component in the preset digital model of the rural highway bridge to be built,

[0081] In a specific embodiment, the displacement influence weights of the bearings and the tops of the piers in the digital model of the rural highway bridge to be constructed are greater than those of other components.

[0082] In a specific embodiment, the deflection influence weights of the beam and the bridge deck in the digital model of the rural highway bridge to be constructed are greater than those of other components.

[0083] It should be noted that the rotation angle refers to the angle of rotation of the cross section of the bridge structure relative to its original position when it is subjected to external forces. The size of the rotation angle reflects the rigidity of the bridge structure. A smaller rotation angle means that the bridge has higher rigidity, while a larger rotation angle may indicate greater structural flexibility or potential structural problems.

[0084] It should be noted that deflection refers to the vertical displacement of any point in the bridge structure relative to its original position when it is under load. In simple terms, it is the degree to which the bridge bends downward. For a well-designed bridge, the deflection should be controlled within a safe range to ensure the stability and durability of the structure. Excessive deflection will not only affect the appearance and use function of the bridge, but may also pose a threat to the integrity of the structure.

[0085] As a preferred solution, the specific analysis process of step 5 further includes: according to the vibration information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the vibration amplitude and frequency of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained, and they are respectively recorded as B i 、F i .

[0086] By analyzing the formula The vibration coefficient ψ2 of the rural highway bridge to be built under the action of earthquake load is obtained, where B0 and F0 represent the threshold values ​​of the vibration amplitude and frequency of the preset bridge components respectively.

[0087] As a preferred solution, the specific analysis process of step 5 further includes: obtaining the values ​​of various internal forces of various components in the digital model of the rural highway bridge to be built under the action of seismic load according to the internal force information of each component in the digital model of the rural highway bridge to be built under the action of seismic load, and recording it as g iu , u represents the number of the u-th internal force, u=1,2,...,v.

[0088] Extract the expected values ​​of various internal forces of each component in the digital model of the rural highway bridge to be built stored in the database and record them as

[0089] By analyzing the formula The internal force compliance coefficient of the rural highway bridge to be built under the action of earthquake load is obtained as ψ3, where e represents the natural constant, △g iu It represents the deviation threshold of the u-th internal force of the ith component in the digital model of the rural highway bridge to be built under the preset seismic load.

[0090] It should be noted that the internal force of the bridge structure refers to the force generated by the internal components of the bridge under the action of external loads. These forces are the result of the interaction between the internal parts of the structural materials to resist the external loads and maintain the stability of the structure and the unchanged shape.

[0091] In a specific embodiment, the internal forces in the bridge structure include, but are not limited to, axial force, shear force, bending moment, torque, lateral force, etc.

[0092] It should be noted that the internal force of the bridge structure should be controlled within the range allowed by the structural material and design. If the designed bridge structure is too conservative, the internal force is far lower than the bearing capacity of the material, which will lead to oversized structure, waste of materials and increased costs. On the contrary, if the internal force is close to the bearing limit of the material, although it can save materials, it will increase the risk of structural failure and reduce the safety margin.

[0093] As a preferred solution, the specific analysis process of step five also includes: according to the damage information of each component in the digital model of the rural highway bridge to be built under the action of seismic load, obtaining the length and position of each crack in each component in the digital model of the rural highway bridge to be built under the action of seismic load, as well as the area and position of each damage.

[0094] The crack influence factor and damage influence factor of each area of ​​each component of the rural highway bridge to be built are set. According to the location of each crack and the location of each damage in each component of the digital model of the rural highway bridge to be built under the action of seismic load, the crack influence factor of each crack area in each component of the digital model of the rural highway bridge to be built under the action of seismic load and the damage influence factor of each damage area are screened and recorded as ε ij , j represents the number of the j-th crack, j=1, 2, ..., m, and j′ represents the number of the j′-th damage, j′=1, 2, ..., m′.

[0095] By analyzing the formula The damage coefficient ψ4 of the rural highway bridge to be built under earthquake load is obtained, where r ij 、z ij′ They represent the length of the jth crack in the i-th component and the damaged area at the j′th location in the digital model of the rural highway bridge to be built under earthquake load, respectively, and η △r , κ △z They respectively represent the influence factors corresponding to the preset unit crack length and unit damage area.

[0096] As a preferred solution, the specific analysis process of step 5 further includes: substituting the deformation coefficient ψ1, vibration coefficient ψ2, internal force compliance coefficient ψ3 and damage coefficient ψ4 of the rural highway bridge to be built under the action of seismic load into the analysis formula The seismic performance index ξ of the rural highway bridge to be built is obtained, where σ1, σ2, σ3, and σ4 represent the weights of the preset deformation coefficient, vibration coefficient, internal force compliance coefficient, and damage coefficient, respectively, and σ1+σ2+σ3+σ4=1.

[0097] As a preferred solution, the specific analysis process of step five also includes: comparing the seismic performance index of the rural road bridge to be built with a preset seismic performance index warning value; if the seismic performance index of the rural road bridge to be built is greater than or equal to the preset seismic performance index warning value, the seismic performance of the rural road bridge to be built meets the requirements; otherwise, the seismic performance of the rural road bridge to be built does not meet the requirements, and the feedback is given to the design team of the rural road bridge to be built.

[0098] In this embodiment, when evaluating the results of the bridge seismic response simulation, the present invention analyzes the responses of various parts of the bridge in various dimensions, such as deformation, vibration, damage and internal force, thereby improving the reliability and accuracy of the evaluation results of the bridge's seismic performance, ensuring the overall stability and safety of the bridge, and facilitating the identification of potential weak links in the bridge, providing reference opinions for the design team, so that the bridge meets the requirements of the seismic design specifications.

[0099] The above contents are merely examples and explanations of the concept of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, they shall all fall within the protection scope of the present invention.

Claims

1. A method for evaluating the seismic performance of rural highway bridges, characterized in that: The steps include: Step 1: Establishment of digital model of bridge: obtain geometric characteristic information, material property information, structural detail information and boundary condition information of the rural highway bridge to be built through design drawings of the rural highway bridge to be built and field survey of the area where the rural highway bridge to be built is located, and establish the digital model of the rural highway bridge to be built using computer-aided design software and finite element analysis software; Step 2: Seismic hazard assessment of the area where the bridge is located: obtain an earthquake prediction model for the area where the rural highway bridge is to be built through the earthquake zoning map of the area where the rural highway bridge is to be built, and obtain earthquake historical records for the area where the rural highway bridge is to be built, and assess the comprehensive earthquake hazard index for the area where the rural highway bridge is to be built; Step 3: Obtain and input the appropriate seismic load for the bridge: According to the comprehensive seismic hazard index of the area where the rural highway bridge to be built is located, analyze the appropriate seismic load for the rural highway bridge to be built and input it into the digital model of the rural highway bridge to be built; Step 4: Obtaining bridge response under earthquake load: Obtaining the response information of each component in the digital model of the rural highway bridge to be built under earthquake load, wherein the response information includes deformation information, vibration information, internal force information and damage information; Step 5: Comprehensive evaluation and feedback of bridge seismic performance: Based on the response information of each component in the digital model of the rural highway bridge to be built under the action of seismic load, comprehensively evaluate the seismic performance index of the rural highway bridge to be built, judge whether the seismic performance of the rural highway bridge to be built meets the requirements, and provide feedback; The specific analysis process of step 2 includes: S1: Obtain the seismic zoning map of the area where the rural highway bridge is to be built from the seismic agency of the area where the rural highway bridge is to be built; Obtain the latitude and longitude coordinates of the rural highway bridge to be built, and mark the specific geographical location of the rural highway bridge to be built on the seismic zoning map of the area where the rural highway bridge to be built is located; According to the specific geographical location of the rural highway bridge to be built, the earthquake parameters predicted for the specific geographical location are read on the earthquake zoning map, and the earthquake activity information predicted for the area where the rural highway bridge to be built is obtained, wherein the earthquake activity information includes earthquake time distribution, earthquake spatial distribution, earthquake frequency and earthquake intensity, and an earthquake prediction model for the area where the rural highway bridge to be built is built; S2: extracting the historical records of earthquakes in the area where the rural highway bridge to be built is located stored in the database, and obtaining the seismic wave data of each historical earthquake in the area where the rural highway bridge to be built is located, wherein the seismic wave data includes the amplitude, frequency and duration of the seismic wave; S3: extract the influencing factors corresponding to the time distribution of each earthquake and the spatial distribution of each earthquake stored in the database, and select the influencing factors corresponding to the predicted time distribution of earthquakes and the spatial distribution of earthquakes in the area where the rural highway bridge is to be built, and record them as δ1 and δ2 respectively; The predicted earthquake frequency and earthquake intensity in the area where the rural highway bridge is to be built are denoted as h and p respectively; By analyzing the formula Get the expected earthquake risk factor φ of the area where the rural highway bridge is to be built 预期 , where h0 and p0 represent the preset thresholds of earthquake frequency and earthquake intensity, respectively, a1 and a2 represent the preset weights of earthquake frequency and earthquake intensity, respectively, and a1+a2=1; S4: The amplitude, frequency and duration of each historical earthquake in the area where the rural highway bridge is to be built are recorded as b x 、f x ,t x , x represents the number of the x-th earthquake in history, x=1,2,...,y; By analyzing the formula Get the historical earthquake risk factor φ of the area where the rural highway bridge is to be built 历史 , where b0, f0, t0 represent the thresholds of the amplitude, frequency and duration of the preset seismic wave, respectively, c1, c2, c3 represent the weights of the amplitude, frequency and duration of the preset seismic wave, respectively, c1+c2+c3=1; S5: Calculate the weighted average of the expected earthquake risk factor and the historical earthquake risk factor in the area where the rural highway bridge is to be built, and obtain the comprehensive earthquake risk index of the area where the rural highway bridge is to be built.

2. A rural highway bridge seismic performance evaluation method according to claim 1, characterized in that: The specific analysis process of step three is as follows: Extract the basic information of simulated seismic wave force corresponding to each range of comprehensive earthquake hazard index stored in the database, wherein the basic information includes direction, intensity, frequency and duration; according to the comprehensive earthquake hazard index of the area where the rural highway bridge to be built is located, screen and obtain the basic information of simulated seismic wave force corresponding to the comprehensive earthquake hazard index of the area where the rural highway bridge to be built is located; record it as the basic information of simulated seismic wave force suitable for the rural highway bridge to be built; then obtain the suitable seismic load for the rural highway bridge to be built and input it into the digital model of the rural highway bridge to be built.

3. A rural highway bridge seismic performance evaluation method according to claim 1, characterized in that: The specific analysis process of step 5 includes: According to the deformation information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the maximum displacement, maximum rotation angle and maximum deflection of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained, and they are recorded as l i ,θ i , τ i , i represents the number of the i-th component in the digital model of the rural highway bridge to be built, i = 1, 2, ..., n; By analyzing the formula The deformation coefficient ψ1 of the rural highway bridge to be built under the action of earthquake load is obtained, where l0, θ0, τ0 represent the threshold values ​​of the maximum displacement, maximum rotation angle and maximum deflection of the preset bridge components, β l-i , β θ ' -i , β τ ″ -i They respectively represent the displacement influence weight, rotation influence weight and deflection influence weight of the i-th component in the preset digital model of the rural highway bridge to be built, 4. A rural highway bridge seismic performance evaluation method according to claim 3, characterized in that: The specific analysis process of step 5 also includes: According to the vibration information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the vibration amplitude and frequency of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained, which are recorded as B i 、F i ; By analyzing the formula The vibration coefficient ψ2 of the rural highway bridge to be built under the action of earthquake load is obtained, where B0 and F0 represent the threshold values ​​of the vibration amplitude and frequency of the preset bridge components respectively.

5. A rural highway bridge seismic performance evaluation method according to claim 4, characterized in that: The specific analysis process of step 5 also includes: According to the internal force information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the values ​​of various internal forces of each component in the digital model of the rural highway bridge to be built under the action of earthquake load are obtained and recorded as g iu , u represents the number of the u-th internal force, u=1,2,...,v; The expected values ​​of various internal forces of various components in the digital model of the rural highway bridge to be built stored in the database are extracted and recorded as By analyzing the formula The internal force compliance coefficient ψ3 of the rural highway bridge to be built under the action of earthquake load is obtained, where e represents the natural constant and Δg iu It represents the deviation threshold of the u-th internal force of the ith component in the digital model of the rural highway bridge to be built under the preset seismic load.

6. A rural highway bridge seismic performance assessment method according to claim 5, characterized in that: The specific analysis process of step 5 also includes: According to the damage information of each component in the digital model of the rural highway bridge to be built under the action of earthquake load, the length and position of each crack in each component in the digital model of the rural highway bridge to be built under the action of earthquake load and the area and position of each damage are obtained; The crack influence factor and damage influence factor of each area of ​​each component of the rural highway bridge to be built are set. According to the location of each crack and the location of each damage in each component of the digital model of the rural highway bridge to be built under the action of seismic load, the crack influence factor of each crack area in each component of the digital model of the rural highway bridge to be built under the action of seismic load and the damage influence factor of each damage area are screened and recorded as ε ij , j represents the number of the j-th crack, j = 1, 2, ..., m, j′ represents the number of the j′-th damage, j′ = 1, 2, ..., m′; By analyzing the formula The damage coefficient ψ4 of the rural highway bridge to be built under earthquake load is obtained, where r ij 、z ij′ They represent the length of the jth crack in the i-th component and the damaged area at the j′th location in the digital model of the rural highway bridge to be built under earthquake load, respectively, and η Δr , κ Δz They respectively represent the influence factors corresponding to the preset unit crack length and unit damage area.

7. A rural highway bridge seismic performance assessment method according to claim 6, characterized in that: The specific analysis process of step 5 also includes: Substitute the deformation coefficient ψ1, vibration coefficient ψ2, internal force compliance coefficient ψ3 and damage coefficient ψ4 of the rural highway bridge to be built under seismic load into the analysis formula The seismic performance index ξ of the rural highway bridge to be built is obtained, where σ1, σ2, σ3, and σ4 represent the weights of the preset deformation coefficient, vibration coefficient, internal force compliance coefficient, and damage coefficient, respectively, and σ1+σ2+σ3+σ4=1.

8. A rural highway bridge seismic performance assessment method according to claim 1, characterized in that: The specific analysis process of step 5 also includes: The seismic performance index of the rural road bridge to be built is compared with the preset seismic performance index warning value. If the seismic performance index of the rural road bridge to be built is greater than or equal to the preset seismic performance index warning value, the seismic performance of the rural road bridge to be built meets the requirements; otherwise, the seismic performance of the rural road bridge to be built does not meet the requirements, and the feedback is given to the design team of the rural road bridge to be built.

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