摘要
正态信息扩散法是一种有效的推断岩土参数概率密度函数的方法,但仍存在窗宽h选择和样本区间确定问题。因此,提出以判定系数最大为目标,以0.1h步长改变初始窗宽值的正态信息扩散最优窗宽确定方法,且最优窗宽与直方图存在匹配关系,建立合理的直方图是岩土参数概率分布推断的前提。在此基础上,提出以2σ统计原理为基础,参考偏度系数c进行调整,“收窄”样本区间的区间取值法。工程实际测试样本的统计结果表明:最优匹配窗宽下的信息扩散分布所得到的概率密度函数优于h窗宽下的概率密度函数,5组岩土参数测试样本在窗宽取为h时,判定系数均小于0.9,在最优窗宽下,拟合判定系数均大于0.97,K-S检验值至少减小0.01;5组样本“收窄”样本边界后获得的正态信息扩散分布在首、尾端均未出现负值、波动情况。
The normal information diffusion method is an effective method for inferring probability density functions of geotechnical parameters,but the problems of window width selection and sample interval determination are still there.A method for determining the optimal window width of the normal information diffusion is proposed herein through taking the maximization of the determination coefficient as the objective and changing the initial window width by the step length of 0.1 h.Moreover,as a matching relationship exits between the optimal window width and the histogram,the establishment of reasonable histogram is the premise of inferring the probability distribution of geotechnical parameters.On this basis,an interval value-taking method is put forward,which narrows the sample interval by means of taking 2σ statistical principle as the basis and adjusting with the reference of the skewness coefficient c.The statistical results of the relevant engineering testing samples show that the probability density function obtained from the information diffusion distribution under the optimal matching window width is better than that under h window width.The determination coefficients of 5 groups of geotechnical parameter testing samples are all less than 0.9 when h is taken as the window width,while the fitting determination coefficients are all larger than 0.97 and the K-S test value is reduced at least by 0.01 under the optimal window width.After narrowing the boundaries of 5 groups of the samples,no negative values or fluctuations of the obtained normal information diffusion distributions appear at the first section and the end of all the probability density function curves.
作者
孔令奇
李翠娟
KONG Lingqi;LI Cuijuan(School of Materials and Environmental Engineering,Chengdu Technological University,Chengdu 610031,Sichuan,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,Sichuan,China)
出处
《水利水电技术（中英文）》
北大核心
2021年第11期219-228,共10页
Water Resources and Hydropower Engineering
基金
国家自然科学基金资助项目(51308466)。
关键词
岩土参数
概率分布
正态信息扩散法
窗宽
判定系数
geotechnical parameters
probability distribution
normal information diffusion
window width
determination coefficient
作者简介
通信作者:孔令奇(1980-),男,讲师,硕士,从事岩土工程可靠度和数据挖掘技术研究。E-mail:5929985@qq.com。
