某高速公路K39高路堤下软基处理方案及效果研究

Study on Treatment Scheme and Effect of Soft Foundation under K39 High-fill Embankment of a Highway

为合理处理某高速公路高填路堤下软弱地基,保证路堤的稳定性,运用有限差分数值软件FLAC3D对采用挖除换填石碴和抛石挤淤两种方案进行对比分析。结果表明:两种处理方式的沉降均满足要求,且与规范法的计算值基本一致;但是抛石挤淤方案因难以确保淤泥全部挤出,从而稳定性不满足要求。通过施工过程中的沉降及深部侧向位移观测,选用挖除换填的处理方法是可行的,但应严格控制路堤的填筑速率和质量,确保施工过程中的稳定性。

In order to reasonably treat the soft foundation under high-fill embankment of a highway and ensure the stability of embankment, such two schemes as excavation of replaced rock ballast and throwing stones to packing sedimentation were analyied comparalively by using finite difference numerical software FLAC3D. The results show that the settlement of such two schemes meets the requirements and is basically consistent with the calculated value based on specification approach. However, the latter did not meet the stability requirements because it is difficult to ensure the sludge could be extruded completely. Through the settlement and deep lateral displacement observation during construction, the former scheme is feasible, but the filling speed and quality of the embankment should be strictly controlled so as to ensure the stability during construction.