基于Fisher判别法的多年冻土融沉等级的判别

Classification of Permafrost Thawing Grade Based on Fisher Criterion

为探究砂土、粉土在多年冻土区的融沉特性,选取含水率、干密度、超塑含水率、融沉系数为融沉分级的判定指标,建立Fisher判别分析模型对土样进行融沉等级的判定。得出结论:1)单因素分析可见土样含水率、干密度以及超塑含水率分别与土样融沉系数之间关系R^(2)>0.7;2)土样的融沉等级主要取决于多因素之间相互作用的结果,以多因素分析结果得出,土样多因素与融沉系数之间关系R^(2)>0.82;3)Fisher判别法恰好具有对多因素同时分析的优势,结果表明Fisher判别分析法提高了判别等级,使融沉等级的结果判别更准确。可在多年冻土区管道地基土含水量过大的情况下,提供可行、快捷的判定方法,同时为多年冻土区冻土融沉等级的判定提供参考。

In order to explore the thawing settlement characteristics of sand and silt in permafrost regions,water content,dry density,superplastic water content and thawing settlement coefficient are selected as the judgment indicators for thawing settlement grading.A Fisher discriminant analysis model is established to determine the thawing settlement grade of soil samples.Conclusion:1)Single factor analysis shows that the relationship between water content,dry density,and superplastic water content and thawing settlement coefficient R^(2)>0.7,respectively;2)The degree of thawing settlement of soil samples mainly depends on the interaction between multiple factors.According to the results of multi factor analysis,the relationship between multiple factors and thawing settlement coefficient of soil samples R^(2)>0.82;3)Fisher discriminant analysis has the advantage of analyzing multiple factors simultaneously,and the results show that Fisher discriminant analysis improves the discrimination level,making the result discrimination of melting and settling levels more accurate.It can provide a feasible and fast judgment method when the water content of pipeline foundation soil in permafrost regions is too high,and provide reference for the judgment of thawing settlement grading of permafrost regions.