工程科学与技术2025，Vol.57Issue(6)：81-92,12.DOI:10.12454/j.jsuese.202400018
近断层脉冲型和远场长周期地震动作用下隔震结构的动力响应与调谐减震控制
Dynamic Response and Seismic Control of Isolated Structures Using a Tuned Mass Damper Under Near-fault Pulse-type and Far-fault Long-period Ground Motions
摘要
Abstract
Objective Long-period ground motions have a serious impact on long-period structures and may even cause damage.Currently,seismic isolation technology has demonstrated excellent technical advantages.However,it remains essential to evaluate whether isolated structures with long-period characteristics will be significantly affected by long-period ground motions.Furthermore,it is necessary to verify whether incorporating a tuned mass damper(TMD)can improve the seismic performance of isolated structures subjected to such unique ground motion characteristics. Methods To ensure the reliability of the analysis results,50 near-fault pulse-type ground motions and 50 far-fault long-period ground motions were selected as input seismic loads based on relevant screening criteria.For the near-fault pulse-type ground motions,NGA-West2 is used as the initial screening database.The correlations between pulse period and response spectrum,as well as between PGV/PGA and response spectrum,are analyzed.Finally,a threshold of PGV/PGA>0.2 is used as an additional screening criterion.For the far-fault long-period ground motions,the weighted square average of the periodicity of the ground motion amplification coefficient spectrum between 2 s and 6 s is considered as the boundary parameter of ground motions,with a threshold value greater than 0.4 defining long-period ground motions.The acceleration response spectra of the selected records are significantly higher than the standard design response spectrum,exhibiting obvious long-period characteristics.Based on the dynamic characteristics of isolated structures,19 simplified single-degree-of-freedom isolated structure models are established,each with a yield displacement of 0.75 mm,post-yield stiffness ratio of 1∶13,and yield-weight ratios ranging from 0.01 to 0.10.The isolation bearing adopts a bilinear model.To efficiently process large amounts of data,a MATLAB program based on the Newmark-β method was self-developed,and its accuracy was verified through comparison with results obtained from commercial software.The amplitudes of the selected ground motion acceleration are adjusted to five intensity levels of 200,300,400,510,and 600 cm/s2.Under the above calculation conditions,the maximum dis-placement response of the isolation layer and the maximum acceleration response of the superstructure were obtained through elastic-plastic time-history analyses.Subsequently,the correlations among the dynamic responses of the isolated structure,post-yield stiffness ratio,ground motion type,and ground motion intensity were analyzed.The tangent stiffness corresponding to the maximum displacement was used to define the equivalent stiffness,and the equivalent damping ratio was determined according to the principle of energy consumption.The parameters of the TMD were optimized by controlling the mean square value of the structural displacement response.Finally,the damping rate of the TMD on the peak displacement of the isolation layer and the acceleration of the superstructure was analyzed.The study considered both single-degree-of-freedom and multi-degree-of-freedom isolated structures. Results and Discussions The results indicate that under long-period ground motions,the isolation layer exhibits large displacement responses.To effectively control the maximum displacement of the isolation layer,the yield-weight ratio of the isolation layer should be more than 0.06.How-ever,considering the safety of non-structural components in the superstructure,the yield-weight ratio should not exceed 0.07 to avoid excessive acceleration responses in the superstructure.Under far-fault long-period ground motions,the control effect of the TMD on the displacement of the isolation layer and the acceleration response of the superstructure increases with an increase in the input ground motion intensity.The TMD is ef-fective in controlling the dynamic response of the isolated structure subjected to rare and extremely rare ground motions.In contrast,under near-fault pulse-type ground motions,the hysteretic delay in the tuning response of the TMD causes a poor damping effect on the displacement of the isolation layer.As the yield-weight ratio increases,the damping effect worsens and may even become negative.Nevertheless,the acceleration re-sponse of the superstructure has a relatively obvious damping effect. Conclusion Under different intensity levels of ground motion,the difference in the degree of nonlinearity of the isolation layer can cause detun-ing of the TMD,which might lead to significant differences in the damping effect.Therefore,the input level of the ground motion must be care-fully considered in the design of TMDs.关键词
长周期地震动/隔震结构/调谐减震控制/近断层脉冲/远场长周期Key words
long-period ground motions/seismic isolated structures/tuned mass damper/near-fault pulse-like/far-fault long-period分类
土木建筑引用本文复制引用
康迎杰,张泽文,刘庆宽,潘鹏..近断层脉冲型和远场长周期地震动作用下隔震结构的动力响应与调谐减震控制[J].工程科学与技术,2025,57(6):81-92,12.基金项目
国家自然科学基金项目(52208493) （52208493）
河北省自然科学基金项目(E2022210038 （）
E2022210078) （）
河北省高等学校科学技术研究项目(BJK2023038) （BJK2023038）
中央引导地方科技发展资金项目(236Z5410G) （236Z5410G）
