滞后阻尼下场地地震反应等效Rayleigh阻尼优化解  

An optimization solution for equivalent Rayleigh damping for site seismic response under hysteretic damping

作　　者：程业[1] 潘旦光[1,2] CHENG Ye;PAN Dan-guang(Department of Civil Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Key Laboratory of Urban Underground Space Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学土木系,北京100083 [2]北京科技大学城市地下空间工程北京市重点实验室,北京100083

出　　处：《岩土力学》2021年第7期2023-2030,2040,共9页Rock and Soil Mechanics

基　　金：土木工程防灾国家重点实验室开放基金(No.SLDRCE15-01)。

摘　　要：为将场地地震反应分析中与频率无关的滞后阻尼,等效为便于时域分析的黏滞阻尼,提出了滞后阻尼转换频率优化算法,在此基础上构建等效Rayleigh阻尼计算的优化方法。以单自由度滞后阻尼体系等效黏滞阻尼模型的加速度累积误差最小构造目标函数,建立滞后阻尼转换频率优化算法。以21条地震波作为输入,统计分析了自振频率、滞后阻尼比和卓越频率对滞后阻尼转换频率的影响。计算结果表明最优滞后阻尼转换频率主要受自振频率影响,而滞后阻尼比和卓越频率影响很小。在此基础上,以场地地表加速度反应误差最小为目标函数,建立了滞后阻尼下等效Rayleigh阻尼系数的优化方程。以一个河谷场地地震反应为例,分析比较了所提方法和传统Rayleigh阻尼构造方法的计算精度,验证所提方法的精度与有效性。In order to make the frequency independent hysteresis damping in site seismic response analysis equivalent to the viscous damping for time domain analysis,an optimization method is proposed to optimize the conversion frequency of hysteresis damping,and on this basis,the optimization method of equivalent Rayleigh damping calculation is constructed.Firstly,the objective function is constructed by minimizing the cumulative acceleration error of the equivalent viscous damping system of the single degree of freedom hysteretic damping system,and the optimization algorithm of the hysteretic damping conversion frequency is established.Then,taking 21 seismic waves as input,the effects of natural frequency,hysteresis damping ratio and dominant frequency on the hysteresis damping conversion frequency are analyzed statistically.The results show that the optimal conversion frequency of hysteretic damping is mainly affected by the natural frequency,while the influences of hysteretic damping ratio and dominant frequency are very small.On this basis,taking the minimum ground acceleration response error as the objective function,the constrained optimization equation for solving Rayleigh damping coefficient is established.Finally,taking the seismic response of a valley site as an example,the computational accuracy of the proposed method and the traditional Rayleigh damping structure method are analyzed and compared,and the accuracy and effectiveness of the proposed method are verified.

关 键 词：场地反应 滞后阻尼 Rayleigh阻尼系数 滞后阻尼转换频率 优化方法 

分 类 号：TU435[建筑科学—岩土工程] P315.9[建筑科学—土工工程]