基础隔震结构不确定参数敏感性分析

Uncertainty parameters sensitivity analysis of base-isolated structures

隔震结构系统参数的不确定性和地震的随机性可能会导致结构响应意想不到的偏移,导致大幅减少安全性评价的准确度和精密度,因此有必要探究隔震支座的不确定性因素对结构响应的影响。本文着重研究基础隔震钢筋混凝土结构的不确定性因素,包括结构的不确定性和地震作用的不确定性。采用龙卷风图对结构不确定参数进行敏感性分析,并对比隔震与非隔震结构的参数敏感性;提出基于我国国情的双响应面法,利用响应面模型同时考察地震动和基础隔震结构的不确定性对地震响应的影响。结果表明:隔震技术可以减小结构不确定性的影响并且地震动的不确定性对结构的影响大大超过结构本身的不确定性。

As the randomness of the earthquake and the inherent uncertainty of the structure,unexpected shifts might occur in the structure response,leading to a significant reduction in accuracy and precision of safety evaluation. Therefore,it is necessary to explore the influence of the uncertainty inherent in isolators on the structural response. This paper focuses on the study of the uncertainty of the base-isolated reinforced concrete structure,including the structural uncertainty and the stochastic earthquake. The parameter sensitivity of the random variables is analyzed by using tornado diagrams and compared for both the base-isolated and non-isolated structure. This paper proposes a dual response surface method based on China＇s national conditions,and uses the response surface model to investigate the impact of the uncertainty within in earthquake and structure on earthquake response. Results show that the base-isolation technology can reduce the influence of the uncertainty within structure and the influence of the randomness within the ground motion considerably exceeds the uncertainty within the structure.