冻融作用引起的黄土边坡剥落机理研究

项目名称： 冻融作用引起的黄土边坡剥落机理研究

项目编号： No.40802068

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 交通运输

项目作者： 叶万军

作者单位： 西安科技大学

项目金额： 20万元

中文摘要： 坡面剥落是黄土边坡变形破坏的一种主要形式，冻融循环是导致黄土边坡剥落的主导因素之一。本项目在对西北黄土地区黄土边坡剥落病害进行调查的基础上，开展在冻融循环条件下黄土土性试验，对典型黄土边坡剥落定点观测，采用CT识别技术，研究了冻融土样的损伤细观结构，确定了不同土性黄土样的冻融损伤劣化规律及冻融剥落行为，提出了黄土边坡剥落的劣化破坏模式，建立了冻融黄土的损伤演化方程；得出不同黄土在不同状态下单轴抗压强度、弹性模量与冻融次数的量化关系式，分析了其冻融耐久性；揭示在不同冻融循环次数、冻结温度、冻结速度等因素下黄土边坡剥落形成扩展方式，建立黄土边坡剥落病害形成与冻融循环次数、冻结温度、冻结速度等各影响因子之间的定量关系；预测黄土边坡剥落体扩展范围；探索在冻融环境下黄土边坡剥落形成的成因机理。该项目的研究无疑是黄土边坡病害的勘察、评价及防治的基础，具有重要的理论与实际意义。

中文关键词： 黄土边坡；剥落；试验；冻融循环；成因机理；

英文摘要： Slope spalling is one major form resulting in loess slope deformation and damage. And the freeze-thaw cycle is one of the major factors for loess slope spalling. In this project, based on the investigation for the loess slope spalling in the loess area of northwest China, loess feature tests are performed under freeze-thaw cycle conditions in order for carrying on fixed-point observation for the typical loess slope spalling by CT Identification Technology, studying the freeze-thaw soil sample damage meso-structure, and determining the deterioration law of the freeze-thaw loess; obtaining the quantitative relation among the uniaxial compressive strength, the elastic modulus, and the freeze-thaw times to analyze the freeze-thaw durability under different staus of loess; disclosing the loess slope spalling forming and expanding modes under various factors' effect, including freeze-thaw cycle times, freezing temperature, and speed, etc., and establishing the quantitative relation between the forming of loess slope spalling damage and various effecting factors like the freeze-thaw cycles, freezing temperature, and freezing speed, etc.; predicting the expanding scope of the loess slope spalling; and exploring the cause of formation of loess slope spalling in freeze-thaw environment. The study of this project is no doubt the fundation of renaissance, evaluation, and prevention and treatment for the loess slope peeling. It is of both important theoretical and practical meanings.

英文关键词： loess slope;spalling;test;freezing andthaw cycle; mechanism;