Study On Fatigue Risk Assessment Of Steel-concrete Composite Segment And Maintenance Decision-model

According to the steel-concrete composite segment has been applied in thebridge structure progressively, establishing fatigue damage risk assessment andresearch about maintenance decision-mode of steel-concrete composite segment,issignificant to guarantee the safety of the bridge.The core content is divided into three parts: the influence factors ofsteel-concrete joining section fatigue and the determination of fatigue took place, thelife cycle risk assessment study due to fatigue and the selection of steel pipe supportplan and its impact on cost analysis. Its core idea is introduced the fatigue concept ofsteel-concrete joining section to summarize the influence factors of steel-concretejoining section fatigue, and through ANSYS to get the actual fatigue took place ofcomponent and fatigue stress amplitude. And through S-V curve to get actual fatigue,then use the steel-concrete joining section risk probability model of the riskassessment to calculate risk damage probability and fatigue reliability index, based onthe fatigue to get with the steel-concrete joining section risk probability, in order tounite with economics formula, choose the maintenance cost and benefit parameters tofit the multiple objective optimization principles. On the basis, building the life periodcost analysis and prediction theory model on the steel-concrete joining section to laygroundwork.The main study contents and research results are as following:1) Life cycle’s framework construction based on the research in the fatigue effectof the steel-concrete joining section.Building up the research framework of the steel-concrete joins section life cycletheory through general research methods. Construction the target system of thesteel-concrete joins section life cycle, analysis the key elements relationship instructural life cycle study. Further analysis main courses of the steel-concrete joiningsection fatigue failure. Settle down the basic contents of the structure whole life cycleresearch. 2) The fatigue influence factors of the steel-concrete joining sectionAccording to the study on the existing research status, category, cause analysisand protective measures of the highway the steel-concrete joining section fatigue bysimple description. It gives us the systematic, comprehensive expounds on thesteel-concrete joining section fatigue failure and its cause. Using ANSYS to analyzesteel-concrete joining section of the bridge, ensure the fatigue took place, providingtheoretical basis to the rest of the article is provided based in the fatigue damagestudy.3) Research in the steel-concrete joining section life cycle risk assessment due tofatigueAnalysis the connotation and significance of the steel-concrete joining sectionrisk assessment, research for steel-concrete joining section risk assessment analysis ofprobability of risk injury methods and corresponding loss model, based on the risk ofbenefit function decision model, set up analysis methods of the steel-concrete joiningsection risk assessment. Calculated component fatigue and the probability randomload of failure of the component fatigue which combined with bridge status indicators,get the fatigue of the component level groundwork.4) Analysis in steel-concrete joining section maintenance plan selection and itsimpact on costAccording to fatigue risk factors,economic factors and the connotation ofsteel-concrete joining section life cycle maintenance, with a detailed description of thesteel-concrete joining section under the influence of fatigue risk determine the fatigueof the component level, unite with economics formula. It chooses the maintenancecost and benefit parameters to fit the multiple objective optimization principles. Andon this basis, building the life period cost analysis and prediction theory model on thesteel-concrete joining section. Using EXCEL to set up the mathematical modelLCASF could use in the long span hybrid girder cable-stayed bridge life cycle costbased on the fatigue. 5) Summarize base on the research aboveSummarizing and analysing the whole thesis, putting forward the innovation pointsand the problems is solved that provides reference for future’s fatigue risk under theinfluence of components for the research and risk assessment of the risks maintenancecost analysis and offers the possible custody program recommendations at the sametime.Overall, due to the steel structure bridge construction and investment is huge andthe consumption of e resource is great. We earnestly need to strengthen steel structurebridge’s life cycle theory and its application in order to save costs and get long-termbenefits.