黄土公路阶梯状高路堑边坡稳定性研究

 为揭示黄土公路阶梯状高路堑边坡的稳定性状，依托阎良—禹门口高速公路黄土高边坡工程，对非扰动黄土阶梯状高路堑边坡模型进行离心试验研究，采用有限元分析软件ANSYS对阶梯状高路堑边坡稳定性进行数值分析，深入研究黄土公路阶梯状高路堑边坡的变形发展过程、破坏特征及其稳定性。研究结果表明：非饱和黄土阶梯状多级矮坡在发生破坏前会发生明显的侧向变形，最大水平位移发生在1/3坡高且向内平距2/3坡脚处，边坡的变形存在先垂直、后水平的特点；非扰动黄土边坡发生侧向变形时，在坡内存在很短距离的无水平应变区；黄土阶梯状多级矮坡的稳定性主要受宏观坡率的控制，高边坡的整体稳定性不受次级矮坡的影响；阶梯状多级矮坡利用黄土的直立特性，采用大于70°坡角的多级矮坡来消除降雨对坡面的冲刷，可最大限度地增加坡面的降雨入渗量，减少坡面产流，为防护边坡植物的生长创造好的立地条件。阶梯状多级矮坡是黄土地区公路路堑边坡较好的一种坡型，具有良好的工程和应用价值。

STUDY OF STABILITY CHARACTERISTICS OF MULTI-STAIR HIGH CUT SLOPE IN LOESS HIGHWAY

In order to study the stability characteristics of the multi-stair high cut slope in loess highway，the centrifugal test was carried out based on loess slope engineering of Yanliang—Yumenkou highway，and numerical analysis method was used to analyze the stability behavior of multi-stair high cut slope by ANSYS program modeling，including the deformation process，destruction character，and stability characteristics. The results show that the lateral deformation will occur before the damage of multi-stair low unsaturated loess slope，and the maximum horizontal displacement appeared in 1/3 slope height and from 2/3 slope toe，and the characteristic of slope deformation is vertical firstly，and then horizontal. When the lateral deformation of unsaturated loess slope appears，there is a very short region of no horizontal strain in the loess slope. The stability of multi-stair-low slope is mainly controlled by macro-ratio of slope，but there is no influence of secondary low slope on high slope stability. Multi-stair-low slope，where inclination is above 70°，can eliminate the surface washing out by upstanding characteristic of loess. Therefore，the water infiltration is increased and the runoff generation is decreased. A good site condition is created for the protection of plant growth. Multi-stair-low slope is a well form in slope engineering of loess area highway，which has good engineering and application values.