Application of rational end cross members consisting of composite structure for seismic restrainers in earthquake to steel girder bridges

We have developed two rational end cross members to conveniently install seismic restrainers. One is a reinforced concrete end cross beam for steel plate twin girder bridges. The other is a steel plates- concrete sandwich end diaphragm for steel box girder bridges. Both of them are categorized as composite construction in steel and concrete. Their half scaled model tests could verify their sufficient strengths against the design horizontal forces transmitting through the seismic restrainers in earthquake. Based on the satisfactory test results, their design methods have proposed. Thus, they have been applied successfully to bridges now in service on Kita Kobe Route of Hanshin Expressway Public Corporation in Japan.