软土地区顶管基坑开挖对高速路堤的影响分析

摘要:

借助上海某顶管工程下穿高速公路项目,通过建立有限元模型分析基坑开挖对高速路堤的影响,通过数值模型与实测数据对比,变形规律基本相似,最大数值偏差在13%以内,模型具有一定的参考价值。工作坑距离路堤坡脚大于3倍开挖深度,路堤的变形非常微弱,可忽略。接收坑距离路堤坡脚2.6倍开挖深度,路堤有了明显的变形。建设条件允许时,基坑距离高速坡脚的距离宜控制在3倍开挖深度以上。当基坑距离路堤小于3倍开挖深度时,建议硬路肩做适当坡面防护等加强措施。

Abstract:

With the help of a pipe jacking project under the expressway in Shanghai, the influence of foundation pit excavation on the expressway embankment was analyzed by establishing a finite element model. Through the comparison between the numerical model and the measured data, the deformation law was basically similar, and the maximum numerical deviation was within 13%. The model had a certain reference value. The working pit was more than 3 times the excavation depth from the embankment slope toe, and the deformation of the embankment was very weak and could be ignored. The receiving pit was 2.6 times the excavation depth from the embankment slope toe, and the embankment had obvious deformation. If the construction conditions was permitted, the distance between the foundation pit and the toe of the high-speed slope should be controlled at more than 3 times the excavation depth. If the distance between the foundation pit and the embankment will be less than 3 times the excavation depth, it should be recommended to take appropriate slope protection and other strengthening measures for the hard shoulder.