云南鲁甸某既有框架结构在长周期地震动作用下隔减震加固研究

Study on seismic isolation and reinforcement of an existing frame structure under long period ground motion in Ludian,Yunnan Province

建筑结构在长周期地震动与普通地震动作用下地震响应有所不同。运用ETABS建立云南鲁甸某5层既有框架结构非线性模型,分别输入远场类谐和长周期地震波、近断层脉冲型地震波和普通地震波进行罕遇地震下的非线性时程分析,并运用层间隔震和阻尼减震两种方法进行加固改造。结果表明:在长周期地震动作用下,既有建筑地震响应明显,层间位移显著增大;在远场类谐和长周期地震动作用下既有建筑地震响应大于近断层脉冲型地震动作用;运用层间隔震和阻尼器减震改造均能减小既有建筑地震响应;长周期地震动影响较大区域建议采用层间隔震加固,影响较小区域建议直接采用阻尼减震加固。

The seismic response of building structures under long period ground motion was significantly different from that under ordinary ground motion.Five-story existing frame structure model is established by ETABS in Ludian,Yunnan Province,the nonlinear time history analysis of rare earthquakes is carried out by inputting far-field harmonic-alike ground motion,near fault pulse type seismic wave and ordinary seismic wave,and the two methods of mid-story isolation and supplemental viscous damping are used for reinforcement.The results show that under the action of long period ground motion,the seismic response of the existing buildings is obvious,the inter-story displacement and inter-story displacement angle increase significantly;the seismic response of the existing buildings under the action of far-field harmonic-alike ground motion is greater than that under the action of near fault pulse type seismic wave;the seismic response of existing buildings can be reduced by using mid-story isolation and supplemental viscous damping;it is suggested to use mid-story isolation in the area with large influence of long-period ground motion and use supplemental viscous damping in the area with small influence.