铁路膨胀土路堤变形控制方法研究

Study on Deformation Control Method of Railway Expansive Soil Embankment

为控制铁路膨胀土路堤运营期内变形,科学确定膨胀土填料的压实控制标准,对膨胀土路堤不同压实控制方法下的变形量进行了计算,提出铁路膨胀土路堤变形控制方法;结合南昆铁路南宁至百色段增建二线膨胀土路堤试验段工程现场监测结果进行验证。计算结果表明:由湿法重型击实所确定的压实控制指标填筑的膨胀土路堤总变形量较小,最大沉降量为40.5 mm,应采用湿法击实曲线实测93%最大干密度对应的含水率作为膨胀土压实控制含水率;监测结果表明:路堤在将近一年运营期内仅发生沉降变形,最大沉降量为37.0 mm。其膨胀土路堤变形控制方法具有较高可靠性。

In order to control the deformation of railway expansive soil embankment during the operation period and scientifically determine the compaction control standard of expansive soil filler,the deformation of expansive soil embankment under different compaction control methods is calculated,and the deformation control method of railway expansive soil embankment is put forward,which is verified by relying on the monitoring results of engineering site of the second line expansion soil embankment test section of Nanning to Baise Section of Nanning—Kunming.The calculation results show that the total deformation of expansive soil embankment filled by the compaction control index determined by wet heavy compaction is small,and the maximum settlement is 40.5 mm,so the moisture content corresponding to 93%maximum dry density of wet side of wet compaction curve should be used as the compaction control moisture content of expansive soil.The monitoring results show that the embankment will only undergo settlement deformation during the operation period of nearly one year,and the maximum settlement is 37.0 mm.The deformation control method of expansive soil embankment in this paper has high reliability.