Construction of a cable bridge component fire resistance and toughness evaluation system and a using method thereof

Abstract

The application discloses a kind of cable bridge component fire damage toughness evaluation system construction and use method, it is related to bridge fire safety assessment technical field.Construction method includes: cable bridge component is divided into structural component and non-structural component, respectively, establish independent fire damage state classification standard for two kinds of components, determine fire response characteristic parameter and set its quantitative mapping relationship between fire damage state grade, determine the recommended repair measures and repair quota parameters corresponding to each fire damage state grade, above-mentioned information is associated and integrated to form component fire damage toughness evaluation system.Use method includes: obtaining component fire response characteristic parameter, input component fire damage toughness evaluation system to determine fire damage state grade, output recommended repair measures and repair quota parameters.The present application introduces the concept of toughness into component level fire damage assessment, realizes the quantitative through from damage determination to repair decision, provides technical support for bridge rapid assessment and repair decision after fire.

Description

Technical Field

[0001] This invention relates to the field of bridge fire safety assessment technology, and in particular to the construction and application method of a fire damage toughness evaluation system for cable bridge components. Background Technology

[0002] In cable-stayed bridges, key load-bearing components such as main cables, suspenders, and stay cables are prone to material strength degradation, stiffness reduction, and load-bearing capacity decay under the combined effects of high temperature and high stress in a fire. Simultaneously, the redistribution of internal forces in localized components after fire can affect the overall structural stress state of the bridge, thus threatening its overall safety performance. Currently, domestic and international research on cable-stayed bridge fire problems mainly focuses on the heat transfer characteristics, mechanical property degradation, and fire resistance limit analysis of bridge components under fire conditions. Most studies employ thermo-mechanical coupled numerical simulation methods to investigate the evolution of the temperature field and failure mechanisms of components under fire, and to assess the fire resistance limit temperature and fire resistance time of the components.

[0003] However, existing research still has the following shortcomings: First, most studies focus on the critical failure state of components, lacking an evaluation system for quantitatively classifying different fire damage levels; second, existing fire damage assessments mainly refer to building structure-related standards, lacking a systematic fire damage classification method that covers multiple component types and is tailored to the characteristics of cable-stayed bridges; third, existing studies focus more on the damage to structural components themselves, while giving less consideration to the post-fire repair needs of non-structural components such as bridge deck pavement and railings; fourth, existing assessment methods usually lack a comprehensive consideration of repair costs, repair time, and post-disaster recovery capabilities, making it difficult to meet the needs of rapid assessment and recovery decision-making after a bridge fire; fifth, with the gradual application of fire-resistant coatings, aerogel composite materials, and other fire protection measures in cable-stayed bridges, existing fire damage assessment methods have not yet systematically considered the impact of fire-resistant protective layer damage on the fire damage status, repair measures, and recovery capabilities of components.

[0004] In recent years, the concept of "resilience" has been increasingly applied to the field of disaster resistance in engineering structures. Unlike traditional methods that only focus on structural damage, resilience theory places greater emphasis on the structure's ability to maintain function and recover after a disaster. Therefore, introducing the concept of resilience into the field of fire assessment of cable-stayed bridge components helps to comprehensively consider the safety, economy, and recoverability of bridges after a fire, providing a basis for bridge fire-resistant design, fire prevention measures, and post-disaster repair decisions.

[0005] In summary, current technologies lack a suitable evaluation system and construction method for assessing the fire toughness of cable-stayed bridge components that comprehensively considers the fire damage characteristics of both structural and non-structural components, and integrates damage classification, repair measures, and repair quota parameters. Therefore, there is an urgent need to establish a standardized evaluation system that can quantitatively characterize the degree of fire damage to components and correlate it with repair decisions, providing technical support for damage assessment, repair decisions, and fire toughness analysis after cable-stayed bridge fires. Summary of the Invention

[0006] To address the aforementioned technical shortcomings, the purpose of this invention is to provide a method for constructing and using a fire damage toughness evaluation system for cable-stayed bridge components, which introduces the concept of toughness into fire damage assessment at the component level. By establishing the correspondence between fire damage status levels, fire response characteristic parameters, recommended repair measures, and recommended repair quota parameters, a quantitative assessment of the degree of fire damage to bridge components and their post-disaster recovery capacity is achieved. This enables a comprehensive evaluation from fire response to repair decision-making, providing technical support for damage assessment, repair decision-making, and fire toughness analysis after a bridge fire.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] This invention provides a method for constructing a fire damage toughness evaluation system for cable-stayed bridge components, comprising the following steps:

[0009] S1: Component Classification: The components of the target cable bridge are divided into structural components and non-structural components;

[0010] S2: Fire damage status classification: Establish independent fire damage status classification standards for the structural components and non-structural components respectively, and define the fire damage status description corresponding to each fire damage status level;

[0011] S3: Establish a mapping relationship: Determine the fire response characteristic parameters that can quantitatively characterize the degree of fire damage to components, and set quantitative thresholds for each fire damage state level of each type of component to establish a mapping relationship between fire response characteristic parameters and fire damage state level.

[0012] S4: Determination of repair quota parameters: For each fire damage status level, determine the corresponding recommended repair measures, and determine the repair quota parameters based on the recommended repair measures;

[0013] S5: Establish a component fire damage toughness evaluation system: Integrate the fire damage status level, fire response characteristic parameters, recommended repair measures, and repair quota parameters to form a component fire damage toughness evaluation system for fire damage assessment and repair decision-making of cable bridge components.

[0014] Preferably, in step S1, the structural components are those that provide load-bearing capacity or maintain the overall stability of the structure, including main cables, suspenders, stay cables, cable clamps, anchor cups, ear plates, stiffening girders, and bridge towers; the non-structural components are those that do not provide load-bearing capacity but affect the bridge's functionality, including bridge deck pavement, railings, guardrails, expansion joints, drainage pipes, maintenance walkways, lighting facilities, and air clamps (sealing and clamping components of the main cable dehumidification system).

[0015] Preferably, in step S2, the fire damage status of the structural components is divided into five levels, corresponding to intact, minor, slight, moderate and severe, respectively; the fire damage status of the non-structural components is divided into four levels, corresponding to intact, minor, moderate and severe, respectively; for specific component types, the fire damage status description of each level is further refined into a description reflecting the unique damage characteristics of the component.

[0016] Preferably, in step S3, the fire response characteristic parameters include temperature parameters, temperature state ratio parameters, and mechanical degradation indicators; the temperature parameters refer to the temperature values ​​at specific points on or inside the component surface; the temperature state ratio parameters refer to the proportion of the component whose temperature exceeds a preset critical temperature to the whole; the mechanical degradation indicators include the load-bearing capacity reduction factor, load ratio, and strength reduction percentage.

[0017] Preferably, the quantitative threshold in step S3 is determined based on one or more of the following factors, including: the high-temperature physical and chemical properties of the fireproof material or anti-corrosion coating of the component, the high-temperature mechanical property degradation law of the steel or concrete material of the component body, and the stress state of the component under fire.

[0018] Preferably, the suggested repair measures in step S4 include one or more of the following: surface repair, local repair, component reinforcement, partial replacement, and overall replacement; the repair quota parameters include unit repair cost and unit repair time.

[0019] Preferably, in the component fire damage toughness evaluation system, each fire damage state level is provided with a fire damage state description, a judgment basis established by quantitative thresholds of fire response characteristic parameters, recommended repair measures, and repair quota parameters.

[0020] Preferably, the target cable bridge is a suspension bridge or a cable-stayed bridge.

[0021] This invention also provides a fire damage toughness evaluation system for cable-stayed bridge components, comprising:

[0022] The data acquisition module is used to acquire fire response characteristic parameters of the target bridge components;

[0023] Storage module, used to store the fire damage toughness evaluation system of the constructed components;

[0024] The level determination module is used to determine the fire damage status level of the target bridge component based on the fire response characteristic parameters and the mapping relationship between the fire response characteristic parameters and the fire damage status level in the component fire damage toughness evaluation system.

[0025] The output module is used to retrieve and output the corresponding suggested repair measures and repair quota parameters from the component fire damage toughness evaluation system based on the fire damage status level determined by the level determination module.

[0026] This invention also provides a method for using a fire damage toughness evaluation system for cable-stayed bridge components, comprising:

[0027] Obtain fire response characteristic parameters of the bridge components to be evaluated;

[0028] The fire response characteristic parameters are input into the component fire damage toughness evaluation system. The fire damage status level of the component is determined by using the quantitative mapping relationship between the fire response characteristic parameters and the fire damage status level in the component fire damage toughness evaluation system.

[0029] Based on the determined fire damage level, the corresponding suggested repair measures and repair quota parameters are read and output from the component fire damage toughness evaluation system.

[0030] Preferably, the fire response characteristic parameters are obtained from on-site detection data after a fire or from the results of thermo-mechanical coupling numerical simulation analysis.

[0031] Beneficial effects:

[0032] (1) Introducing the concept of resilience into fire damage assessment at the component level breaks through the limitations of traditional methods that only focus on the fire resistance limit of components. By directly linking the fire damage status level classification with repair costs and repair time, the assessment system is upgraded from a "damage rating tool" to a "resilience assessment tool" that takes into account both the degree of damage and the cost of recovery. This reflects the core connotation of recovery capacity in resilience theory and provides technical support at the component level for the assessment of bridge fire resistance resilience.

[0033] (2) Incorporating structural and non-structural components into a unified evaluation system, the system systematically considers the different damage characteristics and repair needs of structural components such as main cables, suspenders, and stay cables, as well as non-structural components such as bridge deck pavement and railings under fire, filling the gap in existing research that only focuses on structural components and ignores fire damage to non-structural components.

[0034] (3) Establish a hierarchical correspondence between the fire damage status level and the recommended repair measures and repair quota parameters, so that the evaluation results can provide a quantitative basis for the selection of repair schemes and the estimation of repair costs, and provide a quantitative basis for bridge fire-resistant design and post-disaster repair decision-making, thus solving the problem that the existing assessment methods cannot meet the needs of rapid assessment and recovery decision-making after bridge fires.

[0035] (4) The high-temperature physical and chemical properties of fireproof materials and anti-corrosion coatings are comprehensively considered in the quantitative threshold setting. It can be applied to the fire damage evaluation of components with and without fire protection, and can meet the actual needs of the current development of fire protection technology for cable bridges.

[0036] (5) It provides a standardized evaluation system construction method and supporting evaluation methods. The construction process is clear and highly operable. Those skilled in the art can adjust and expand the evaluation system according to the target bridge type, material parameters, etc. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 A flowchart illustrating a method for constructing a fire damage toughness evaluation system for cable-stayed bridge components, as provided in an embodiment of the present invention. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] This embodiment takes a suspension bridge with a main span of 2180 meters as an example and provides a method for constructing a fire damage toughness evaluation system for cable-stayed bridge components, specifically including the following steps:

[0041] S1: Component classification;

[0042] The components of the target suspension bridge that are susceptible to fire are divided into structural components and non-structural components.

[0043] Structural components are those that provide load-bearing capacity or maintain the overall stability of the structure, while non-structural components are those that do not provide load-bearing capacity but affect the bridge's functionality.

[0044] In this embodiment, structural components include the main cable, suspenders, cable clamps, anchor cups and lugs, stiffening girders (main beams), and bridge towers; non-structural components include bridge deck pavement, railings and guardrails, expansion joints, drainage pipes, maintenance access roads above the main cable, lighting facilities, and air clamps (sealing and clamping components of the main cable dehumidification system). The above examples are merely illustrations, and other types of components affected by fire are not excluded.

[0045] S2: Fire damage status classification;

[0046] Establish separate fire damage status classification standards for structural components and non-structural components, and define the corresponding fire damage status descriptions for each level.

[0047] This embodiment refers to Clause 5.2 of GB / T 38591-2020 "Evaluation Standard for Seismic Toughness of Buildings" and Clause 3.2 of JTG / T H21-2011 "Evaluation Standard for Technical Condition of Highway Bridges". Combining the damage characteristics of cable-stayed bridge components in vehicle fire accidents, the fire damage status of structural components is divided into five levels, as shown in Table 1; the fire damage status of non-structural components is divided into four levels, as shown in Table 2; and the fire damage status description under each level is defined.

[0048] Table 1:

[0049]

[0050] Table 2:

[0051]

[0052] S3: Determination of fire response characteristic parameters;

[0053] For different types of components, fire response characteristic parameters are determined to quantitatively assess their fire damage level. In this embodiment, the component fire response characteristic parameters are divided into three categories based on the component type:

[0054] ①Temperature parameters: These refer to the temperature value at a certain point on or inside the surface of a component, such as the surface temperature of the main cable, the temperature of the outer steel wire of the suspender cable, and the surface temperature of the steel clamp.

[0055] ② Temperature state ratio parameter: refers to the proportion of the part of the component that reaches the preset critical temperature to the whole, such as the proportion of the number of steel wires with a temperature exceeding 300℃ in the main cable to the total number of steel wires;

[0056] ③Mechanical degradation index: refers to the degree of degradation of the mechanical properties of components caused by fire, such as the load-bearing capacity reduction factor, load ratio, and the decrease in strength of the outer steel wire.

[0057] Those skilled in the art can select one or more of the above three types of parameters according to the component type and evaluation requirements.

[0058] S4: Establishment of quantitative judgment criteria;

[0059] For each fire damage state level of each component, a quantitative threshold for the fire response characteristic parameter in S3 is set, and a mapping relationship between the two is established. The setting of the quantitative threshold comprehensively considers the high-temperature physical and chemical properties of the component's fireproof materials and anti-corrosion coatings, the high-temperature mechanical property degradation law of the component's steel or concrete materials, and the stress state of the component under fire.

[0060] The specific value of the quantitative threshold can be determined based on the results of high-temperature material tests, finite element analysis results, data from engineering fire case studies, or experience in bridge repair projects.

[0061] S5: Determining the repair quota parameters;

[0062] For each fire damage level, corresponding recommended repair measures are determined, and repair quota parameters are established based on these recommended measures. The repair quota parameters include unit repair cost and unit repair time, the specific values ​​of which are determined based on relevant bridge engineering budget quotas, local material and labor market unit prices, and experience surveys of similar bridge repair projects.

[0063] In this embodiment, the recommended repair measures are determined based on the component type and the degree of damage, and typically include one or more of the following: surface repair, local repair, component reinforcement, partial replacement, and overall replacement.

[0064] Surface repair includes, for example, recoating with anti-corrosion coatings and repairing fireproof layers;

[0065] Local repairs include rust removal and local reinforcement of the fire-affected area, and grouting to seal concrete cracks.

[0066] Component reinforcement, such as wrapping with steel plates or reinforcing with carbon fiber cloth, etc.

[0067] Partial replacement includes, for example, cutting off and replacing the damaged section of steel, or replacing sealing elements;

[0068] Complete replacement, such as replacing the entire cable or replacing the expansion joint device.

[0069] The above examples are merely illustrations. Those skilled in the art can determine the appropriate recommended repair measures based on the actual type of the component and the characteristics of the damage.

[0070] S6: Establish a component fire damage toughness evaluation system;

[0071] A correspondence was established between fire damage status levels, fire response characteristic parameters, recommended repair measures, and repair quota parameters to form a fire damage toughness evaluation system for cable-stayed bridge components. In this component fire damage toughness evaluation system, each fire damage status level for each type of component is associated with a fire damage status description, a judgment basis established from quantitative thresholds of fire response characteristic parameters, recommended repair measures, and repair quota parameters (unit repair cost and unit repair time).

[0072] Based on the general classification standard established in S2, the fire damage status description of each level is further refined to reflect the unique damage characteristics of the component for specific component types.

[0073] This embodiment uses parallel wire slings (without fire protection) and wire rope slings (coated with epoxy fire-retardant paint) in structural components, and railings and guardrails, and air clamps (sealing clamp components of the main cable dehumidification system, coated with epoxy fire-retardant paint) in non-structural components as examples to demonstrate the evaluation system content for specific components. The constructed component fire damage toughness evaluation system is shown in Tables 3-6. For simplicity, only the evaluation parameters of representative components are listed in Tables 3-6; the grade evaluation parameters of other components can be compared accordingly. In Tables 3-6, the specific values ​​of unit repair cost and unit repair time are determined based on relevant budget quotas for bridge engineering, local material and labor market unit prices, and experience surveys of similar bridge repair projects. Tables 3-6 only provide the basis and determination method for these values.

[0074] Table 3:

[0075]

[0076] In Table 3: T0: Damage temperature of PE sheath, taken as 100℃ based on the survey results.

[0077] T1: The temperature at which the galvanized anti-corrosion coating on the sling surface is undamaged, taken as 200℃ based on literature review and experimental research.

[0078] T2: The temperature limit for no damage to the sling wire, which is 300℃ based on literature review and experimental research.

[0079] T3: Upper limit of moderate damage temperature for sling wires, taken as 450℃ based on engineering research.

[0080] The temperature values ​​for T0-T3 can be referenced in Table 3, or adjusted according to the materials used in the actual project, based on experimental data or survey parameters. "Large area" in the context of large-area coking refers to an area exceeding 70% of the total area.

[0081] The load ratio is the ratio of the actual stress on a component under fire conditions to its ultimate bearing capacity.

[0082] Table 4:

[0083]

[0084] In Table 4: T0: Temperature limit for changes in the physical and chemical properties of the fireproof layer material of the suspension cable; for epoxy fireproof coating, it is 80℃.

[0085] T1: Expansion temperature of epoxy fireproof coating for slings, taken as 250℃ according to product properties. After the coating expands, it cannot be used anymore. The fireproof coating and the anti-corrosion layer of steel wire in contact with the fireproof coating must be removed and recoated.

[0086] T2: The temperature limit for no damage to the sling wire, which is 300℃ based on literature review and experimental research.

[0087] T3: Upper limit of moderate damage temperature for sling wires, taken as 450℃ based on engineering research.

[0088] The temperature values ​​for T0-T3 can be referenced in Table 4. Alternatively, the corresponding temperature limits can be adjusted according to the materials used in the actual project, based on test data or survey parameters.

[0089] The load ratio is the ratio of the actual stress on a component under fire conditions to its ultimate bearing capacity.

[0090] Table 5:

[0091]

[0092] In Table 5: T0: The temperature at which the physicochemical properties of the anti-corrosion coating on the surface of the guardrail and railing change or the upper limit of the normal operating temperature, which is taken as 80℃ based on literature research.

[0093] T1: The temperature limit for the steel material of the guardrail and railing body without damage, taken as 300℃ based on literature review.

[0094] T2: Oxidation mutation temperature of the steel material of the guardrail and railing body. According to literature research, 570℃ is taken for carbon steel.

[0095] The temperature values ​​for T0-T2 can be referenced in Table 5. Alternatively, the corresponding temperature limits can be adjusted according to the materials used in the actual project, based on test data or survey parameters.

[0096] Table 6:

[0097]

[0098] In Table 6: T0 a The temperature limit for the transformation of the physical and chemical properties of the fireproof layer on the surface of the gas-insulated coating is 80℃ for epoxy fireproof coating.

[0099] T0 b Damage temperature limit for air clamp sealing elements: 120℃ for high-performance rubber.

[0100] T2: The temperature limit at which the stainless steel body of the gas clamp undergoes sensitization and permanent loss of corrosion resistance, taken as 500℃ based on literature review.

[0101] The temperature values ​​for T0-T2 can be referenced in Table 6. Alternatively, the corresponding temperature limits can be adjusted according to the materials used in the actual project, based on test data or survey parameters.

[0102] Based on the established fire damage toughness evaluation system for cable-stayed bridge components, this embodiment also provides a method for using the system, the specific steps of which are as follows:

[0103] S10.1: Obtain fire response characteristic parameters of the component to be evaluated, including temperature parameters, temperature state ratio parameters, and mechanical degradation indices, through on-site post-fire testing or thermo-mechanical coupling numerical simulation.

[0104] S10.2: Input the obtained fire response characteristic parameters into the component fire damage toughness evaluation system constructed by the above construction method.

[0105] S10.3: Utilize the quantitative mapping relationship between fire response characteristic parameters and fire damage status levels in the component fire damage toughness evaluation system, compare the actual fire response characteristic parameters of the component with the judgment criteria for each level, and determine the fire damage status level of the component.

[0106] S10.4: Based on the determined fire damage level, output the corresponding recommended repair measures and repair quota parameters to provide a basis for damage assessment and repair decisions after a bridge fire.

[0107] For example, a sling is tested and found to have an outer wire temperature of 320℃ and a load ratio of 0.50. According to the criteria in Table 3, it is classified as Level 3 (moderate) damage. The output result is: Recommended repair measures are "repair and reinforce the entire sling, recoat the anti-corrosion layer, and replace the PE sheath," with a corresponding unit repair cost of C and a unit repair time of T. The unit repair cost and repair time can be obtained based on specific values ​​determined through quotas and market research.

[0108] Obviously, the above method is also applicable to similar components of cable-stayed bridges. Those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations of this invention fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for constructing a fire damage toughness evaluation system for cable-stayed bridge components, characterized in that, Includes the following steps: S1: Component Classification: The components of the target cable bridge are divided into structural components and non-structural components; S2: Fire damage status classification: Establish independent fire damage status classification standards for the structural components and non-structural components respectively, and define the fire damage status description corresponding to each fire damage status level; S3: Constructing a mapping relationship: Determining fire response characteristic parameters that can quantitatively characterize the degree of fire damage to components. The fire response characteristic parameters include temperature parameters, temperature state ratio parameters, and mechanical degradation indices. The temperature parameters refer to the temperature values ​​at specific points on or inside the component surface. The temperature state ratio parameters refer to the proportion of the component whose temperature exceeds a preset critical temperature. The mechanical degradation indices include the load-bearing capacity reduction factor, load ratio, and strength reduction percentage. For each type of component, a quantitative threshold for fire response characteristic parameters is set for each fire damage state level to establish a mapping relationship between fire response characteristic parameters and fire damage state level. The quantitative threshold is determined based on one or more of the following factors, including the high-temperature physical and chemical properties of the component's fireproof material or anti-corrosion coating, the high-temperature mechanical property degradation law of the component's steel or concrete material, and the stress state of the component under fire. S4: Determination of Repair Quota Parameters: For each fire damage level, determine the corresponding recommended repair measures, and determine the repair quota parameters based on the recommended repair measures; the recommended repair measures include one or more of the following: surface repair, local repair, component reinforcement, partial replacement, and overall replacement; the repair quota parameters include unit repair cost and unit repair time; S5: Establish a component fire damage resilience evaluation system: Integrate the fire damage status level, fire response characteristic parameters, recommended repair measures, and repair quota parameters to form a component fire damage resilience evaluation system for fire damage assessment and repair decision-making of cable-stayed bridge components; In the component fire damage resilience evaluation system, each fire damage status level of each component is associated with a fire damage status description and a judgment basis established by quantitative thresholds of fire response characteristic parameters, recommended repair measures, and repair quota parameters. The component fire damage resilience evaluation system establishes a hierarchical correspondence between the fire damage status level and the recommended repair measures and repair quota parameters, so that the evaluation results can provide a quantitative basis for the selection of repair schemes and the estimation of repair costs; The method for using the component fire damage toughness evaluation system is as follows: Obtain fire response characteristic parameters of the bridge components to be evaluated; The fire response characteristic parameters are input into the component fire damage toughness evaluation system. The fire damage status level of the component is determined by using the quantitative mapping relationship between the fire response characteristic parameters and the fire damage status level in the component fire damage toughness evaluation system. Based on the determined fire damage level, the corresponding suggested repair measures and repair quota parameters are read and output from the component fire damage toughness evaluation system.

2. The method for constructing the fire damage toughness evaluation system for cable-stayed bridge components according to claim 1, characterized in that, In step S1, the structural components are those that provide load-bearing capacity or maintain the overall stability of the structure, including main cables, suspenders, stay cables, cable clamps, anchor cups, ear plates, stiffening girders, and bridge towers; the non-structural components are those that do not provide load-bearing capacity but affect the bridge's functionality, including bridge deck paving, railings, guardrails, expansion joints, drainage pipes, maintenance walkways, and lighting facilities.

3. The method for constructing the fire damage toughness evaluation system for cable-stayed bridge components according to claim 2, characterized in that, In step S2, the fire damage status of the structural components is divided into five levels, corresponding to intact, minor, slight, moderate and severe; the fire damage status of the non-structural components is divided into four levels, corresponding to intact, minor, moderate and severe; for specific component types, the fire damage status description of each level is further refined into a description reflecting the unique damage characteristics of that component.

4. The method for constructing the fire damage toughness evaluation system for cable-stayed bridge components according to claim 1, characterized in that, The target cable bridge is a suspension bridge or a cable-stayed bridge.

5. The method for constructing the fire damage toughness evaluation system for cable-stayed bridge components according to claim 1, characterized in that, The fire response characteristic parameters obtained are derived from on-site detection data after the fire or from the results of thermo-mechanical coupling numerical simulation analysis.

Images