一维固结条件下黏土微结构再造过程研究和描述  

A method for describing microstructure of clay rebuilding in process of one-dimensional consolidation

作　　者：李顺群[1,2] 高凌霞[3] 柴寿喜[1,2] 王英红[4] 刘双菊[1,2] 

机构地区：[1]天津城市建设学院土木工程系,天津300384 [2]天津城市建设学院天津市软土特性与工程环境重点实验室,天津300384 [3]大连民族学院土木建筑工程学院,辽宁大连116600 [4]天津城市建设学院电子与信息工程系,天津300384

出　　处：《岩土力学》2010年第11期3435-3440,共6页Rock and Soil Mechanics

基　　金：教育部科学技术研究重点项目(No210004);冻土工程国家重点实验室开放基金资助项目(NoSKLFSE200906)

摘　　要：采用冷冻制样方法,对不同固结压力作用下得到的重塑黏土压缩试样进行了真空干燥,对其水平截面、45o截面和垂直截面上获得的SEM照片域微结构参数进行了研究。对简单微结构参数的研究表明,随固结压力增大颗粒体所占比重越来越大。对合成微结构参数的研究包括主成分分析和聚类分析两方面,结果表明,随固结压力增大,第一主成分指标近似线性增大;不同固结压力作用下的样品具有明显的聚类特征,且类内距离随固结压力增大逐渐增大。在建立各种土力学关系时,可以考虑纳入合成微结构参数而并非简单微结构参数,以反映土微结构的整体特征。Vacuum freeze drying method is utilized to prepare samples for SEM from one-dimensional consolidated clay,which is originally remolded and subsequently suffered the 5 grade pressures respectively.And then,simple and synthetical microstructure parameters of SEM photos obtained from horizontal,45o inclined and vertical plane are studied to discover relation between macroscopical mechanics and micro structure.Study of simple parameters shows that grain area ratio and perimeter increase with consolidation pressure while other parameters have no constant tendency.Synthetical parameters come from two data analysis methods,namely principal component analysis and pedigree cluster analysis.It is shown that the first principal component approximately linearly increases with consolidation pressure.Samples can be exactly clustered into several families according to the pressure;and inner distance of a family nonlinearly increases with pressure.Synthetical parameter is distinctly superior to simple parameter in study of soil mechanics because the former can reflect the whole microstructure qualities;but the latter can＇t.

关 键 词：一维固结 微结构再造 主成分分析 聚类分析 

分 类 号：TU411.92[建筑科学—岩土工程]