Appropriate Wrapping Width of Expansive Soil Embankment Built by Enveloping Method

Abstract

In two sections of expansive soil trial embankments of Guangxi Ningming area, four monitoring profiles were set and series of testing elements were buried for field monitoring to find out the appropriate wrapping width. The statistical analysis of the monitoring data of water content, horizontal displacement changed with drying-wetting cycle of seasons in several monitored slopes was carried out. The results shows that, when the horizontal distance to the slope surface in trial embankments is larger than three meters, the variation of soil water content and horizontal displacement are small, the wrapping depth of trial embankments is suitable; the obtained optimum seasons for expansive soil embankment construction in Guangxi are from January to April, and the prominent effect depth of expansive soil in the condition of wetting-drying cycle is 1.49 m; furthermore, the appropriate wrapping width of expansive soil embankment built by the enveloping and wrapping technique in Nan-you Expressway is determined to be 3 m. On the basis of the research, the method of determining the appropriate wrapping width of expansive soil embankment built by the enveloping and wrapping method was put forward.