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With the advances in modern construction technology , the cable-stayed bridge as a beautiful, practical type of bridge , more and more applications in the long-span bridges . The cable-stayed is the most important load-bearing structure of the main beam , engineering live , it 's too short life , greatly affected the normal service of the cable-stayed bridge . In this study, 20 -year cable-stayed cable-stayed bridge in service for Panzhihua Tongzilin analysis . PE sets of protective wire surface there is a serious injury . By scanning electron microscope ( SEM - EDR) , laser scanning confocal microscopy (LSCM) scanning instrument , microscopic analysis of the surface damage , and get the following conclusions : 1 , the study found , there are a few parts of the wire rope freedom elongation ( central wire ) abrasions, but a good metallic luster , no corrosion phenomenon ; small amount of rust near the bridge tower parts ( head , wire ) , and there is some wear and tear , were not found in these two parts of the siltation of the grout . Site ( tail wire ) near the main beam , wire corrosion , damage is most severe , found on the surface of a large number of grout ; affect the life of cable-stayed friction damage and corrosion . Judging from the overall situation , the local concentration and symmetrical trend wire damage , while the cable in the free length of the cushioning effect of the load . 2 , cable-stayed steel wire subject to varying degrees of damage , macro axial injury is micro axial , tangential and radial composite role of the three friction mechanism . The central elongate freely section by the radial and tangential injury have around a depth of 6-8μm , but the head and tail of the wire by the wear mechanism , scratches is covered . Tail wire continuously grind profile plane , together with a large number of corrosion , impact a main part of the cable-stayed life . 3, the surface of the wire EDX analysis showed that the oxygen element and zinc content in the decline , iron on the rise , indicating serious injury in the friction part , the wire surface of the galvanized layer is seriously damaged ; wire is exposed to the air , surface abrasions in constantly ; formed by the other part of the galvanized layer in Zn0 the form homeostasis. Ministries segment wire cross-sectional analysis , found no obvious cracks , but externally by a serious injury , the outline of the cross-sectional edge becomes rough .
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