地震作用下边坡随机动力分析方法的若干进展

ADVANCES IN STOCHASTIC DYNAMIC ANALYSIS OF SLOPES UNDER EARTHQUAKES

不确定性问题是边坡工程抗震设计所面临的巨大挑战。为此,本文综述了近年来在边坡随机动力分析方法方面的相关研究,并探讨了此类分析方法在边坡工程抗震设计中的应用前景。首先,回顾了在边坡动力稳定性方面的已有研究成果,分析了边坡工程中所涉及的不确定性问题。其次,总结了边坡随机动力分析的流程,引入了一种基于概率密度演化的边坡随机动力分析框架。然后重点介绍了随机动力分析中的地震动不确定性,通过典型台站实测资料说明了地震动不确定性的存在性,介绍了基于场地特征的随机地震动模型。在此基础上,阐述了边坡随机动力分析的具体内容,主要包括:(1)边坡随机动力响应分析;(2)边坡动力可靠度分析;(3)边坡地震易损性分析;(4)边坡动力失稳及风险评估;(5)边坡抗震性能优化设计等。最后,回顾了边坡随机动力分析方法的若干进展,分析了所取得的成果并进行了展望。总的来说,边坡随机动力分析将确定性分析拓展到了基于完备概率集的不确定性分析,为边坡工程抗震设计提供了一定的理论参考,但在随机地震动模拟、多随机因素耦合、支护结构优化设计等方面仍需进一步完善。

The uncertainties are great challenges for seismic design of slope engineering.This paper reviews the recent researches on random dynamic analysis methods of slope,and discusses the application prospect of those methods in engineering seismic design.Firstly,this paper reviews previous researches on dynamic stability of slopes and analyses the uncertainty problems involved in slope engineering.Secondly,it summarizes the processes of slope random dynamic analysis.It introduces a framework of slope random dynamic analysis based on probability density evolution.Then,it introduces the research on the uncertainty of ground motions,where the recorded waves of a typical station are used to explain the existence of the ground motion uncertainty,and a random ground motion model based on the site characteristics is discussed.On this basis,the paper identifies the specific contents of random dynamic analysis of slope.They include(1)random dynamic response analysis of slope,(2)dynamic reliability analysis of slope,(3)seismic fragility analysis of slope,(4)dynamic instability and risk assessment of slope,(5)optimal design of seismic performance of slope.At last,the paper briefly introduces some advances of slope random dynamic analysis method,analyses the achievements and prospects.The research of slope seismic is extended from the deterministic analysis to the uncertainty analysis.The paper provides a theoretical reference for the aseismic design of slope engineering.However,it still needs to be further improved in the aspects of random ground motion simulation,multi random factors coupling,and support structure optimization design.