某高速公路膨胀土边坡稳定性数值分析

Numerical Analysis on Slope Stability of Expansive Soil in Certain Expressway

简要论述了非饱和膨胀土的工程特性,对膨胀土边坡的失稳机理进行了初步探析。结合工程实例,在室内试验和现场勘查的情况下,利用岩土工程数值分析软件ANSYS和FLAC,引入膨胀土膨胀力的作用,分析了高速公路膨胀土路堤边坡出现的路面开裂和边坡失稳问题,同时指出雨水对膨胀土边坡稳定性影响很大,特别是在路面出现较长纵向裂缝的情况下。分析结果表明,用ANSYS和FLAC软件都可以自动模拟出边坡失稳的滑移面,但FLAC的模拟结果较ANSYS更与现场情况相吻合。最后指出,该路段的膨胀土边坡处于不稳定状态,需要进行边坡加固治理。

The engineering properties of unsaturated expansive soil are briefly discussed and the mechanism of slope failure for expansive soil is explored. Through laboratory tests and in-site inspection Combining with the practical projects, the existing road cracks and slope failures in the high embankments with expansive soll for certain expressway are analyzed by using the geotechnical numerical analysis software ANSYS and FLAC under the conditions of considering the expansive force of expansive soil. It is pointed that the water from rainfall greatly affects the slope stability of expansive soil, especially when existing plenty of longitudinal cracks. The analysis resuhs indicate that the sliding surface of the unstable slope could be simulated by using the ANSYS and FLAC, but the result from FLAC is more accord with the field condition than that from ANSYS. Finally it is pointed that the slopes in expensive soil at the section of the expressway are unstable which should be reinforced.