坡脚开挖对既有路基边坡稳定性的影响

Influence of Slope Toe Excavation on Stability of Existing Subgrade Slope

公路周边新建建筑物场地基坑开挖对既有路基边坡的稳定性会造成一定影响,可导致公路路面裂缝与边坡失稳问题。以广佛肇高速公路某边坡为研究对象,基于现场监测及数值模拟分析手段,分析了坡脚建筑物基坑开挖对既有公路路基边坡稳定性的影响。结果表明:坡脚建筑物基坑开挖对边坡稳定性影响显著,随着建筑物基坑开挖深度的增加,边坡不同部位的变形出现不同程度的增加,且当只有围护桩支护的基坑开挖至10 m时,边坡稳定性急剧下降,最大超过23.24%,严重威胁到边坡的安全;数值计算结果较好地反应了现场实际工况下边坡的变形发展状况。因此,坡脚建筑物基坑在施工前,应对既有路基边坡的坡脚位置进行足够的加固处理。

The excavation of foundation pits for new buildings around the highway will have a certain impact on the stability of the existing roadbed slope,which can lead to road surface cracks and slope instability.Taking a certain slope of GuangfoZhao Expressway as the research object,being based on on-site monitoring and numerical simulation analysis methods,the influence of the excavation of the foundation pit of the building at the foot of the slope on the stability of the existing highway subgrade slope has been analyzed.The results have shown that the excavation of the foundation pit of the building at the foot of the slope has a significant impact on the stability of the slope.When the protected foundation pit is excavated to 10 m,the stability of the slope drops sharply,exceeding 23.24%at most,which seriously threatens the safety of the slope;the numerical calculation results better reflect the deformation development of the slope under the actual working conditions on site.Therefore,before the construction of the foundation pit of the building at the foot of the slope,sufficient reinforcement treatment should be carried out on the foot of the existing roadbed slope.