山区典型软土路基稳定性影响因素敏感性分析

Sensitivity Analyses of Influencing Factors of Typical Soft Soil Subgrade Stability in Mountain Area

受到地形地貌的影响,山丘地区与平原地区的软土路基稳定性具有明显差异。为研究山区软土路基稳定性,首先分析了各种地形条件下软土路基的存在形式;然后利用Plaxis有限元软件对山区软土路基典型形式的稳定性进行分析;最后计算地形因素对山区软土路基的稳定性的影响;并分析稳定性安全系数对各影响因素的敏感性。研究结果表明,山区软土路基主要有斜坡软土路基、层状软土路基和谷间锅底状软土路基三种形式。斜坡软土路基较平原软土路基易失稳,谷间软土路基较平原软土路基更稳定。斜坡软土路基的稳定性安全系数对各因素的敏感性从大到小依次为填土高度、软土层厚度和软土层倾斜度。谷间软土路基的稳定性安全系数各因素的敏感性从大到小依次为填土高度、软土层覆盖范围和坡脚与山体距离。

The stability between soft soil roadbed in mountain area and plain area is obviously different due to topography. For the study of mountain area soft soil subgrade stability,the form of soft soil subgrade were analyzed on the various terrain conditions firstly,and then the finite element software Plaxis was used to analyze the typical form of soft soil subgrade stability in mountainous area,and finally soft soil subgrade stability of terrain factors on the mountainous area was calculated,and sensitivity analysis of main factors affecting the stability safety coefficient of each was carried out. The results show that the soft soil subgrade in the mountainous areas has three forms：sloped soft soil subgrade,layered soft soil subgrade and pot bottom shape soft soil subgrade in the valle. The sloped soft soil subgrade is less stable and pot bottom shape soft soil subgrade is more stable than plain soft soil subgrade.The stability safety factor of sloped soft soil subgrade has the sensitivity from big to small in order to fill height,soft soil layer thickness and soft soil tilt angle. The stability safety factor of the soft soil subgrade in the valley has the sensitivity from the big to the small in order to the fill height,the soft soil coverage and the distance between the slope foot and the mountain.