含构造节理黄土强度特性研究

Study on strength characteristics of loess with structural joints

构造节理构成了黄土土体的软弱面,极易引发滑坡、崩塌等灾害,是各类黄土地质灾害的构造因素之一。本研究通过对黄土高原域内典型构造节理的调查,分析了黄土构造节理的分布、产状以及形态特征。在此基础上,提出一种新型构造节理模拟方法,并开展无侧限抗压试验和直接剪切试验,得出了如下结论:(1)黄土构造节理产状比较稳定,节理面较为平滑,闭合度较高;(2)通过材料模拟节理面间的接触关系能够有效完善研究的室内实验技术;(3)黄土构造节理与含水率共同影响了黄土体的强度,对其破坏模式起到了控制作用。

Structural joints are widely distributed in loess,which are easy to form soft surfaces of soil and cause disaster,such as landslide and collapse.The joint is one of the structural factors of various geological disasters in loess.The distribution,occurrence and morphological characteristics of structural joints in loess are analyzed,through the investigation of the typical structural joints in the Loess Plateau.On the basis of the above investigation and analysis,a new structural joint simulation technique is presented.Using this technique to prepare specimens containing joints,the unconfined compression test and direct shear test are carried out.The study drew the following conclusions:(1)Structural joints in loess are stable in occurrence,smooth and straight in surface and high in closure.(2)The material simulation of the contact relationship between joint surfaces can effectively supplement the research methods of laboratory experiments.(3)The structural joints and water content of loess together affect the strength of loess body and control the failure mode of the loess body.