EXPERIMENTAL-STUDY OF BRIDGE SEISMIC SLIDING ISOLATION SYSTEMS

An experimental study of a seismically isolated and a comparable nonis olated bridge is presented, The bridge model featured flexible and sti ff piers and, in certain cases, different isolation system properties at the two piers. Designs for application in areas of low to moderate seismic activity and designs for application in areas of strong seismi c activity and all types of soil conditions were tested. All systems c onsisted of sliding bearings and rubber restoring force devices, Moreo ver, fluid viscous dampers were utilized in a system specifically desi gned to withstand the strong and long period level 2 Japanese design m otions while transferring a force to the substructure not more than on e-third of the deck weight and allowing bearing displacements less tha n 200 mm in prototype scale, The analytical modelling of the systems a nd a design example are presented.