Comparative analysis on flexible supporting technology of different types of expansive soil cutting slope in the south and the north of China

The problem of collapse and sliding of expansive soil cutting slope in the expressway of Nanning to Youyiguan and Baise to Longlin in the Guangxi Zhuang Autonomous Region and West Sixth Ring in Beijing municipality has been successfully treated by geogrid reinforced flexible supporting technology. These treated projects have been experienced for six to eleven years. The actual cases of different expansive rock (soil) cutting slopes treated by this technology in the south and the north of China are reviewed and summarized. Three aspects, i.e. the engineering geology and soil characteristics, the forms and characteristics of slope failure, the design plan of treatment considering the impact of soil (rock) properties and climatic environment are compared specifically. The universal validity of using flexible supporting technology to treat expansive soil cutting slope with the characteristic of shallow damage has been verified. The technology needs to be supplemented, modified and perfected based on the actual conditions, and then the world technical problem that different types of expansive rock (soil) subgrade in different areas will be slippery while in cutting can be effectively solved.