Vertical displacement of collapsed bridge in Palau

Vertical displacement of the Korror-Babeldaop (KB) Bridge in Palau is presented. This bridge was built in 1977 by the cantilever method and collapsed 3 months after remedial prestressing in 1996. KB Bridge was a segmental prestressed concrete girder having the world record of 241 m and maximum girder depth of 14.17 m. The final mid-span deflection was in design expected to be 0.53 to 0.65 m but after 18 years it reached 1.39 m and was still increasing. With a very limited amount of official information of the bridge was available and bridge was analyzed by ANSYS finite element program. Presented is an accurate analysis using 5392 hexahedral three-dimensional (3D) finite elements with 9614 nodes by ANSYS. Hognestad concrete model and Solid 65 element type were considered. The actual vertical displacements of free end of the cantilever bridge under truck loading were compared with the 3D finite element analyses results in order to come up with a benchmark model. The collapse reasons of KB Bridge were discussed.