原状膨胀土二维胀缩各向异性试验研究  

EXPERIMENTAL STUDY ON TWO-DIMENSIONAL SWELLING-SHRINKAGE ANISOTROPY OF UNDISTURBED EXPANSIVE SOIL

作　　者：胡瑾 周亚东[2,3] Hu Jin;Zhou Ya-dong

机构地区：[1]中冶武勘工程技术有限公司,武汉430080 [2]天津市软土特性与工程环境重点实验室,天津300384 [3]天津城建大学土木工程学院,天津300384

出　　处：《建筑技术开发》2024年第12期158-161,共4页Building Technology Development

基　　金：国家自然科学基金项目(51608351)。

摘　　要：膨胀土的胀缩变形具有方向性,存在各向异性的问题,横向胀缩变形对膨胀土边坡工程影响不可忽视。为研究原状膨胀土的二维胀缩各向异性,采用简易方法制备竖向、横向原状土样,进行干湿循环、不同初始状态、荷载作用下的膨胀土二维膨胀与收缩各向异性试验。结果表明,竖向胀缩变形大于横向胀缩变形,竖向、横向最大膨胀率与最大收缩率不相等,原状膨胀土二维胀缩变形是不可逆的;干湿循环过程中,原状膨胀土的绝对膨胀率、相对膨胀率、绝对收缩率与相对收缩率,竖向数值均大于横向数值;原状膨胀土的胀缩各向异性与含水率、干密度等初始状态无关。The expansion and contraction deformation of expansive soil is directional and anisotropic.The influence of lateral expansion and contraction deformation on expansive soil slope engineering cannot be ignored.In order to study the two-dimensional swelling-shrinkage anisotropy of undisturbed expansive soil,the vertical and horizontal undisturbed soil samples were prepared by simple method,and the two-dimensional swelling and shrinkage anisotropy tests of expansive soil under dry-wet cycle,different initial states and loads were carried out.The results show that the vertical expansion-shrinkage deformation is greater than the transverse swelling-shrinkage deformation.The maximum vertical and transverse expansion rates are not equal to the maximum shrinkage rate,and the two-dimensional swelling-shrinkage deformation of undisturbed expansive soil is irreversible.During the wetting-drying cycle,the absolute expansion rate,relative expansion rate,absolute shrinkage rate and relative shrinkage rate of the undisturbed expansive soil,and the vertical values are greater than the horizontal values;the swelling-shrinkage anisotropy of undisturbed expansive soil has nothing to do with the initial state such as water content and dry density.

关 键 词：原状 膨胀土 胀缩变形 各向异性 

分 类 号：TU443[建筑科学—岩土工程]