摘要
岩土材料参数由于多种原因具有较大的离散性,对其进行概率统计分析,并优化确定非常必要.以某地区粉质粘土的抗剪强度指标———粘聚力为例,介绍了在获得大样本参数的条件下,进行概率分布拟合的χ2检验法.并以此大样本概型为先验分布,具体工程小样本参数的概型为似然函数,利用Bayes方法得到验后分布的概型参数.计算结果表明,验后分布的方差小于先验分布和似然函数的方差,从而达到优化目的.
Geotechnical parameters of geometerials have large scattering property due to some causes. It is very useful to analyse and optimize the geotechnical parameters using the methods of probability statistics.An example of the cohesion of a silty clay in an area is used. Based on the example,χ~2 check method in fitting probability distribution is introduced under the condition of large sample number. Based on the distribution of the large sample used as the prior distribution and the distribution of a little sample used as the likelihood function, the parameters of the post distribution are given using Bayes method. The calculated results indicate that the variance value of the post distribution is the smallest in the three variance values of the prior distribution, the likelihood function and the post distribution. Therefore the object of optimizing the geotechnical parameters is realized.
出处
《华北水利水电学院学报》
2004年第2期51-54,共4页
North China Institute of Water Conservancy and Hydroelectric Power
关键词
岩土参数
X^2检验法
先验分布
似然函数
验后分布
BAYES方法
geotechnical parameter
χ~2 check method
prior distribution
likelihood function
post distribution
Bayes method
