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The Wando grand bridge has been designed in 2003 and main structure has constructed in 2010. The bridge is composed of 75 m steel tower, 500 m steel girder and 32 cables. This paper presents the design, fabrication, erection, and cable installation of the bridge.The main bridge is 500m long and composed of 70 m, 90 m, 200 m, and 140 m spans. Super structure of Wando grand bridge is orthotropic steel deck with U-rib. The width of the deck is 24.8 m and is composed of four lanes for vehicle + one lane for pedestrian. Diaphragm is located at every 6 m, and interval of U-rib is 0.64 m. The material for main plates is SM520B(tensile strength is 520 MPa) which is used widely for bridge superstructure in Korea. Multi strand cables are installed at 32 points in a 2-face fan type. Total length of cable is 3,587 m and the total length of strand is 188,266 m. The ultimate tensile strength of strand, Fpu is 1,770 MPa. Allowable strength of cable is 0.45 Fpu at completed stage, 0.65 Fpu at erection stage, respectively.The verticality of tower was given as 1/2000 at construction site. Considering construction error, the target for verticality was set to 1/5000. To get the accurate straightness, every structural element at the internal joint of pylon was milled using facing machine. Girder was diveded to nine segments in which 4 segments have been erected by crawler crane and others have been erected by floating crane. As the bridge was constructed at shallow sea zone, special floating crane having 2 booms and 4 hooks was utilized.Geometric control was utilized to make accurate erection. At the first step, weight of some blocks were measured in factory using load cell and compared with shop drawing net weight. The target value of geometric control of the bridge is ± 60mm for girder deflection, ± 35mm for tower horizontal displacement, and 10% for cable tension. Construction has been performed successfully, and there is no adjustment for cable tension. Cable has been installed at average three days erection cycle. As the cable is mono strand type of Freyssinet, ISO tensioning method has been used.The pavement for the bridge was finished last year and bridge has been opened.