黄磊,李喜安,蔡玮彬,乔露
HUANG Lei,LI Xi'an,CAI Weibin,QIAO Lu

• 1:长安大学地质工程与测绘学院
• 2:内蒙古农业大学水利与土木建筑工程学院
• 3:四川省煤田地质工程勘察设计研究院

摘要(Abstract)：

为了深入了解延安新区马兰黄土的粒间作用,揭示其湿陷机理。首先利用扫描电子显微镜观察了黄土的微观结构特征,并且利用IPP图像处理软件对黄土颗粒定量分析,论证了PFC~(2D)软件模拟黄土粒间作用的可行性。然后,基于离散元理论,利用颗粒流PFC~(2D)程序模拟了延安新区不同埋深原状黄土颗粒的分布情况及颗粒间相互作用,以一种直观的方法再现了天然黄土的微观结构特征。对比分析了不同深度黄土颗粒分布及接触力分布与湿陷性的关系。结果表明:骨架颗粒间的作用决定了土体的结构强度,尤其以团粒结构的接触力为主。随着深度的增加,黄土骨架颗粒由点接触方式逐渐过渡到团粒重叠接触,粒间接触力明显增强。PFC~(2D)模拟方法为黄土湿陷性成因机理研究提供了新的思路。
In order to deeply understand the grain effect of Malan Loess in Yan'an new area and to reveal its collapse mechanism, firstly scanning electron microscope was used to observe the microstructure characteristics of loess, and IPP image processing software was used to analyze quantitatively loess particles. Then, based on discrete element theory, the particle flow PFC2 D program was used to simulate the distribution of the undisturbed loess particles and the interaction between the particles in Yan'an new area under different buried depth. The microstructure structure characteristics of the natural loess were visually reproduced. The relationship among the distribution of particles, the contact force and the collapsibility was analyzed. The results show that the structure strength of soil was determined by the action of the skeleton particles, especially the contact force of aggregate contact was dominant. With increase of depths, the loess skeleton particles transit gradually from point-contact to aggregate structure, the contact force decreased also significantly. The PFC2 D method provides a new idea for the research on the formation mechanism of loess collapsibility.

关键词(KeyWords)： 湿陷性试验;湿陷系数;PFC2D;扫描电镜
collapsibility test;coefficient of collapsibility;PFC2D;SEM

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(41572264,41172255,41440044);; 中央高校基本科研业务费资助项目(2014G2260008)~~

作者(Author): 黄磊,李喜安,蔡玮彬,乔露
HUANG Lei,LI Xi'an,CAI Weibin,QIAO Lu

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