Experimental evaluation on in-soil water migration reducing performance of restraining moisture geotextile (RMG)

Engineering materials such as geosynthetics clay liners (GCL) and gravel layers are effective to cut off the in-soil water migration and have been widely employed to stabilize the moisture content of subgrades. However, the moisture stabilizing performance of GCL or gravel layer is usually compromised due to the complexity of service condition. This paper introduces an engineering material named restraining moisture geotextiles (RMG), which is expected to show low permeability as GCL. With characterization of basic properties of RMG, moisture migration column test of silty soil and test cases with employments of RMG, GCL, and gravel layer are performed, respectively. The temperature and moisture fields of soil columns subjected to a freezing-thawing process are measured, and the capillarity and in-soil water migrating behavior are analyzed. Carbon footprints of GCL and RMG are compared and discussed. Test results show that RMG, GCL and gravel layer are effective to cut off the capillarity, but the gravel layer can result in higher moisture content in silty soil due to the vapor migration and capillary isolation. In conclusion, RMG can be an alternative method with low permeability on reducing the in-soil water migration, and is much lighter and more engery-efficient than GCL.