孔内深层强夯挤密法在山区公路软基处理中的应用

Application of Down-Hole Dynamic Consolidation to Expressway′s Soft Foundation in Mountain Areas

介绍了孔内深层强夯挤密法(DDC)的作用机理,针对山区高速公路软基的工程地质特点,首次采用孔内深层强夯挤密法对GZ40勉宁高速公路软基进行了处理,通过对处理后的复合地基的现场静荷载试验和理论分析计算,得出处理后的复合地基承载力提高了近2倍,复合地基承载力和沉降量均满足工程设计要求,同时对该方法进行了社会经济效益分析与评价。工程应用表明该方法处理山区软基效果良好,具有施工方便简单、速度快、无污染、对周围环境影响小和工程造价低等优点,具有广阔的应用前景和推广价值。

This paper introduces the mechanism of down-hole dynamic consolidation （DDC）, according to engineering geological characteristics of expressway＇s soft foundation in mountain areas. Down-bole dynamic consolidation was used for the first time to treat the soft foundation of GZ40 Mian-Ning expressway, the bearing capacity of composite foundation was increased twice, both the bearing capacity and settlement of composite foundation meets the need of engineering design through in-situ static load test and theory calculation, meanwhile, social and economic benefit of this method was also analyzed. Analysis shows the method of down- hole dynamic consolidation has several advantages： convenient and rapid construction, no contamination, no impact on surrounding environment and low cost, etc. So the method of down-hole dynamic consolidation has great practical value and bright market prospect.