基于刚度比的基础隔震结构减震系数  

Seismic Decrease Coefficient of Base Isolation Structure Based on Stiffness Ratio

作　　者：尚守平[1] 王彦 SHANG Shouping;WANG Yan(College of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082

出　　处：《湖南大学学报（自然科学版）》2023年第3期23-31,共9页Journal of Hunan University:Natural Sciences

基　　金：国家“十二五”科技支撑计划项目(2015BAL03B01)。

摘　　要：水平向减震系数是隔震设计的重要指标.将上部结构与隔震层刚度之比作为基本变量,通过双自由度等效模型对减震系数的影响因素进行了理论研究.通过振型分析计算了上部结构的等效转换系数,推导了刚度比形式的内力和减震系数表达式,分析了减震系数的影响因素,计算了隔震结构满足减震系数要求所需的刚度比限值.发现减震系数曲线存在不变量即基准曲线,提出基准点概念.结果表明,刚度比和隔震层阻尼比是减震系数的决定因素,减震系数随刚度比或隔震层阻尼比增大而减小;当刚度比大于4.5或8时,减震系数分别低于0.5或0.4;与5个工程实例对比,减震系数表达式准确性较好.成果整理成表格可供查阅.The Horizontal Seismic Decrease Coefficient(HSDC)is an important parameter in seismic isolated design.This paper investigates the influencing factors of HSDC theoretically in the Two-Degree-of-Freedom equiva⁃lent vibration system,in which the stiffness ratio of superstructure to isolation layer(SRSI)is regarded as a basic variable.The equivalent converting coefficient of the superstructure was calculated by mode-shapes analysis.The in⁃ternal force and HSDC were both derived and expressed in SRSI,and then the influencing factors of HSDC were ana⁃lyzed.The limits of SRSI,required for the seismic isolation structure to meet the requirements of HSDC,were calcu⁃lated according to the design codes.The fixed curve of HSDC was found and defined as the Datum Curve,as well as the concept of Datum Points in HSDC was further proposed for design.The results show that:HSDC is determined by SRSI and the damping ratio of the isolation layer,and furthermore,HSDC decreases with the increase of SRSI and the damping ratio of the isolation layer;the HSDC is lower than 0.5 or 0.4 when SRSI is greater than 4.5 or 8,respectively;the HSDC’s expression gives accurate estimates when comparing with 5 example projects.The results are ar⁃ranged into tables for reference.

关 键 词：基础隔震 隔震结构 刚度比 减震系数 

分 类 号：TU318[建筑科学—结构工程] TU