岩石流变参数鲁棒辨识方法研究  

Research on robust identification of rheological parameters of rocks

作　　者：韩冰[1,2] 王芝银[1] 

机构地区：[1]中国石油大学城市油气输配技术北京市重点实验室,北京102249 [2]中国石油管道公司管道研究中心,河北廊坊065000

出　　处：《岩土力学》2008年第10期2661-2666,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.50374049)资助

摘　　要：基于室内岩石三轴蠕变试验资料对岩石的流变本构模型及流变参数进行辨识,是研究岩石流变力学特性的重要手段。由于受到试验条件和随机噪声的影响,试验数据中经常夹杂有异常值,采用传统的最小二乘法进行参数估计其结果往往会出现较大偏差。为了克服异常值对参数辨识结果的影响,引入统计学中的稳健估计理论,通过对实测的样本资料赋予不同的权重,采用双二次加权最小二乘法对流变参数进行估计。对比试验和计算结果表明,该方法能够有效地减小异常值对辨识结果的影响,在估值精度、收敛性、鲁棒性方面均优于传统的最小二乘估计方法。It is an important method for studying the rheological characteristics of rock to choose an appropriate rheological model and obtain the corresponding parameters based on the triaxial creep experiment of rock in lab. However, there are always a few abnormal values in sample data due to the influence of experiment conditions and random noises; the estimation accuracy may be worse if we use the ordinary least square algorithm to estimate parameters. The robust estimation theory derived from statistics is applied to the parameter identification by using double quadratic iteratively weighted least square algorithm; and it can reduce estimation bias due to the presence of abnormal values. This method is compared with that using ordinary least square estimation; the result shows that the former has high accuracy, uniform convergence and strong robustness, which is better than the ordinary least squares estimation.

关 键 词：三轴蠕变试验 异常值 鲁棒估计 参数辨识 

分 类 号：TU452[建筑科学—岩土工程] TU458.3[建筑科学—土工工程]