【作者】 贾永生；

【导师】 隆威；

【作者基本信息】 中南大学 ， 地质工程， 2007， 硕士

【摘要】 膨胀土是一种特殊的粘性土。我国是膨胀土分布最广泛的国家之一，随着我国高等级公路的大量兴建，开展膨胀土地区公路路堑边坡问题的研究具有重要的现实意义。本文通过理论分析和室内外试验，对膨胀土的性质、判别分类方法和路堑边坡稳定性问题进行了分析研究。通过对赣大高速公路膨胀土的试验研究，分析了膨胀土的成分、结构和物理性质特点及膨胀土的胀缩特性，研究结果表明干湿循环后的膨胀土强度具有强衰减性。从工程实际应用角度对膨胀土的判别和分类方法进行了分析和研究，提出了赣大高速公路膨胀土的综合判别方法。根据膨胀土路堑边坡滑坡的特点，分析了膨胀土滑坡的原因和机理。膨胀土具有亲水性强，强度衰减快，残余强度低等特点，是边坡失稳的内在因素。而外因则是边坡平衡条件的破坏，引起土体结构松弛和应力状态改变。基于边坡稳定性分析的Sarma法，推算出了针对膨胀土路堑边坡稳定性分析的计算公式。对膨胀土路堑边坡进行了开挖过程中的稳定性模拟分析，表明随着开挖的深入或浸水深度的增大，膨胀土路堑边坡的安全系数不断降低。对膨胀土路堑边坡提出了动态分析、综合治理的防护措施。更多还原

【Abstract】 Expansive soil is a special clay soil, which has widely distributed in china. Along with the large-scale construction of highway, it is important to study on the roadbed and slope problems in the districts of the expansive soil.This passage had analyzed the property and the classification and the identification of the expansive soils and the stability of slopes by using the theoretical and the experimental methods.Based on the experiments and inspections of the expansive soils in Ganzhou-Dayu Highway, the compositions, structures, physical properties, the swell-shrink characters of the expansive soils are analyzed. The mechanism of the swell-shrink is discussed. The strength-decaying character is demonstrated by the experimental approach.Considering the specific of the Ganzhou-Dayu Highway project, a classification is suggested. And it may be used for the judgments of the regional expansive soils.The landslide feature of the expansive soil is analyzed. The reason and mechanism of the expansive soil slope is also analyzed. According to the analytical method of the slope stability, the passage has calculated the the Smarm means for the stability of the expansive slope.The dynamic simulated analyses on the stability of the expansive soil slope in the process of digging, fore-and-after of soaking and different soaking depth have been carried out. The results show that with the increase of the digging and the slope soaking depths, the safety coefficient of the trench slope is decreasing. It indicates that the stability of the depth trench slope is controlled directly by the digging effect in the construction stage and by the soaking effect after the construction. Put forward dynamic analysis and comprehensive treatment measure of the expansive soil slope.更多还原