Theoretical Study Of Suspenders’ Replacement Strategies Of Long-span CFST Arch Bridges

Arch bridge has been widely used due to its beautiful styling and reasonable loadingmode, the progress of construction techniques and materials technology has promotedthe rapid development of bridge technology, and new bridge types and the newtechnology appear constantly. Concrete Filled Steel Tubular（CFST）Arch BridgesBridge,as one of the new bridge types, has been widely applied in our country durningthe nearly three decades.Suspender is one of the key mechanical components in this bridge type.Because ofthe lack of design experience in the early years,,diseases such as steel corrosion andfracture,protective cover cracking,anchorage corrosion and damage short suspenderdamages began to appear with the increase of bridges’ service time.These factors lead tothe much shorter actual service life than the design service life.In order to avoid thebridge accident caused by suspender diseases,many bridge suspenders began to bereplaced。 But because of the lack of engineering experience and the relevantspecification,the most choices of strategy for the replacement of the suspenders social atpresent stage was made according to the related engineering experience.Therefore, itwill make great practical significance to study strategy for the replacement of the bridgesuspenders.So the author studied how to develop strategies for the replacement of the bridgesuspenders.The following are the main works in the paper:①Summarized the main factors which affect the service life of these suspenders.Through summing up what these influencing factors have in common;②Analyzed the the failure probability characteristics of series and parallel systemrespectively.③Analyzed the influence of the failure probability for suspender system withdifferent replacement and maintenance strategies,and compared the economy of thestrategies, combined with an engineering example.④Assumed it to be a parallel system, and made the flowchart of optimizingstrategies⑤Summarizes the main points for generating strategy of suspender replacement，and draw the flow chart.