Seismic Performance Evaluation and Displacement Control of Bridges Isolated with FPS

• Main Authors: Gao, Chi-Hong, 高志宏
• Other Authors: Wong Yen-Po
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/79056821774066223943

碩士 === 國立交通大學 === 土木工程學系 === 84 === In this thesis, the feasibility of using sliding isolation bearings, in particular the Friction Pendulum System (FPS), for aseismic design of bridges is verified through numerical simulations. Although it has been shown that isolation can effectively reduce the forces transmitted to the bridge piers, the superstructure of the isolated bridge may be excessive under low-frequency ground excitations. Two approaches are considered to resolve this problem: one by introducing the Tuned Mass Damper (TMD) for displacement control and the other by providing the bridge superstructure with lateral constraint in one end. A numerical procedure referred to as the "multi- support shear balance method" is developed for nonlinear dynamic analysis of continuous bridges isolated with FPS bearings. Results obtained through extensive numerical simulations indicate that the use of TMD is not sufficient for displacement control of the isolated bridge whereas those with lateral constraints on the superstructure present excellent aseismic performance. Under such configurations, negligible displacements of bridge superstructure are observed while significant reductions of pier shears and moments are achieved without extra displacement control devices. The system performs consistently well in seismic areas of both hard and soft soil-profiles.