To improve the seismic performance of the single pylon cable-stayed bridges of con-solidation systems,the concept of the base isolation design was applied to the seismic design of the bridges.By way of example of a single pylon cable-stayed bridge with spans of(1 55+1 55)m,the applicability of the base isolation design was analyzed.The SAP2000 was used to establish the dy-namic finite element model for the bridge.10 seismic waves were selected,the longitudinal time-history analysis was done for the different base isolation schemes having the 4 types of the laminat-ed rubber bearings(RBs)and 5 types of the friction pendulum bearings(FPBs)and the changes of the seismic performance of the bridge after the base isolation design was applied were compared. The results yield that the application of the base isolation design can make the global stiffness of the single pylon cable-stayed bridges decrease and the natural vibration periods increase.The isola-tion layers of the laminated rubber bearings can cause the increase of the girder end displacement and the decrease of the pylon footing bending moment,but the changing laws of the increase and decrease are influenced greatly by the seismic wave characteristics.In the case that the influences of the isolation layers of the friction pendulum bearings on the girder end displacement are not great,the bearings can greatly decrease the pylon bending moment,the changing law of the de-crease is influenced a little by the seismic wave characteristics and the bearings can be used for the base isolation design scheme of the bridges.%为提升固结体系独塔斜拉桥的抗震性能,将基础隔震设计理念应用于桥梁的抗震设计中.以某(155+155)m独塔斜拉桥为背景,分析基础隔震设计的适用性.采用 SAP2000建立桥梁动力有限元分析模型,选取10条地震波,对4种叠层橡胶支座和5种摩擦摆支座基础隔震方案进行顺桥向时程分析,对比采用基础隔震设计后独塔斜拉桥抗震性能的变化.结果表明:基础隔震设计使得独塔斜拉桥的整体刚度降低,自振周期增大;叠层橡胶支座隔震层会引起梁端位移的增大以及塔底弯矩的减小,但变化规律受地震波特性影响较大;摩擦摆支座隔震层在对梁端位移影响不大的情况下,可大幅降低塔底弯矩,且变化规律受地震波特性影响较小,可作为独塔斜拉桥的基础隔震设计方案.
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