摘要
利用动扭剪仪,研究了不同地区(兰州、洛川、杨凌、巩义)黄土的动强度特性以及变形特性。重点研究了不同地区黄土在不同含水率,不同固结应力和振次下的动强度特性及其相互差异。研究表明:各地区黄土动强度特性由强到弱依次是杨凌、巩义、洛川、兰州,总趋势上呈现出由西北向东南逐渐增强的态势;含水率及固结应力对试样强度均影响明显;各地区黄土受含水率影响存在明显差异,随强度的增强对含水率的敏感性增强;非饱和黄土和饱和黄土在强度及变形特性存在明显差异;由四个地区的原状黄土的τdf/σ3与破坏振次N的关系曲线,得出这些地区黄土τdf/σ3~N均没有归一性,但随着含水率的增大归一性趋势逐渐增强。
Some aspects such as the behaviors of dynamic strength and dynamic deformation of the loess in different regions(Lanzhou,Luochuan,Gongyi,Yangling),were studied with the dynamic torsional shear test.The study is focused on the dynamic strength characteristics of the loess under different water content,different consolidation stress and different vibration times in different regions.The research showed that: The dynamic strength characteristics of the loess in different regions from strong to weak were Yangling,Gongyi,Luochuan and Lanzhou ones,the main trend tended rising from the northwest to the southeast.Water content and consolidation stress had significant influence on the dynamic strength of the loess;There were significant differences between the loess in different regions affected by the water content,with the enhance mnet of the strength,the sensitivity of water content is enhanced,too.There were significant differences between the strength and deformation characteristics of unsaturated loess and saturated loess.The relation curves between τdf/σ3 and damage vibration times N of the loess in different regions showed that the τdf/σ3 had no normalized relation,but with the enhancement of water content,it tended to be enhanced.
引文
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