孔内深层强夯法在城市道路路基杂填土处理中的应用研究

Study on Application of Down-hole Dynamic Compaction in Treatment of Miscellaneous Fill in Urban Road Subgrade

在城市道路设计中,若遇到路基范围内存在较深杂填土的情况,需查明其性质、成因、类型、规模,然后综合考虑地质情况、道路等级、周边环境和工程经济等因素来制定处理方案。对西安市某次干路约800m长路基较深杂填土的几种处理方式进行分析比较,在这些处理方式中,孔内深层强夯法(DDC)具有显著优势,它适用于处理深层、不均匀土壤,对周边环境的影响较小,且成本相对较低。因此,最终采用DDC法对杂填土路基进行处理,并对承载力等关键指标检测。检测结果表明,经DDC法处理的路基有效提高了路基承载力,同时路床顶面的压实度和弯沉值也满足了道路设计的要求。

In urban road design,there may be deep miscellaneous fill in subgrade.It is necessary to identify its nature,cause,type and scale,and then comprehensively consider the geological conditions,road grade,surrounding environment and engineering economy to formulate a treatment scheme.Several methods for treating the deep miscellaneous fill of an approximately 800-meter-long subgrade of a secondary trunk road in Xi'an are analyzed and compared.Among these treatment methods,the down-hole dynamic compaction(DDC)has the significant advantages,which is well suited for treating the deep and uneven soil with little influence on the surrounding environment,and its cost is relatively low.Therefore,the method of DDC is ultimately adopted to treat the miscellaneous fill subgrade.And the key indexes of bearing capacity and so on are detected.The detecting results indicate that the subgrade treated by DDC method effectively enhances its subgrade bearing capacity.Additionally,the compaction degree and deflection values of the roadbed top surface meet the requirements of road design.