基于随机动力分析的高土石坝极限抗震能力研究  

Ultimate a seismic capacity of high earth-rock dams based on stochastic dynamic analysis

作　　者：庞锐[1,2] 卢韵竹 季睿 徐斌[1,2] PANG Rui;LU Yunzhu;JI Rui;XU Bin(School of Infrastructure Engineering,Dalian University of Technology,Dalian 116024,China;The State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学建设工程学院,辽宁大连116024 [2]海岸和近海工程国家重点试验室(大连理工大学),辽宁大连116024

出　　处：《岩土工程学报》2024年第10期2237-2244,共8页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(52279096,52279125,52379117)。

摘　　要：地震动的随机性对大坝的动力响应影响较大,极限抗震能力作为大坝抗震安全性能的重要环节,在评估过程中也应该充分考虑荷载随机性的影响。基于大量高土石坝随机动力有限元计算,探究坝顶震陷率和坝坡累计滑移量两个重要坝体变形指标之间的关系,并建议了土石坝安全控制标准。利用概率密度演化法对高土石坝进行极限抗震能力分析。结果表明:震陷率随着累计滑移量的增大而增大,二者之间符合逻辑斯蒂增长模型;取10%的超越概率,以250m规则高面板堆石坝和高心墙堆石坝为例,极限抗震能力分别为0.7g~0.75g和0.8g~0.85g;从概率角度提出了评估大坝极限抗震能力的新方法。The randomness of seismic motion significantly affects the dynamic response of dams.The ultimate capacity is a critical factor for the seismic safety of dams,thus during the assessment process the influences of load randomness should be thoroughly considered.Based on a large number of random dynamic finite element calculations for high earth-rock dams,the relationship between the settlement rate of dam crest and the cumulative sliding displacement of slope,two important deformation indices of dams is studied.Additionally,the safety control standards for earth-rock dams are proposed.The probabilistic density evolution method is used to analyze the ultimate a seismic capacity of dams.The results indicate that the settlement rate increases with the cumulative sliding displacement and follows a logistic growth model.Taking the exceedance probability of 10%as an example,the ultimate a seismic capacities for a 250 m-high faced rockfill dam and a high-core rockfill dam are approximately 0.7g~0.75g and 0.8g~0.85g,respectively.A new probabilistic approach is proposed for evaluating the ultimate a seismic capacities of dams.

关 键 词：随机动力分析 高土石坝 极限抗震能力 谱表达-随机函数法 概率密度演化法 

分 类 号：TU43[建筑科学—岩土工程]