Engineering and Geological Characteristics of Sliding Sand Hillslopes in Granitic Mountains of West China

摘要

In the granitic mountains of West China, the spectacular scenery that has developed under arid conditions includes the presence of sand ramps lying at the toe slopes. The analysis of ramp geomorphology and sedimentology, and rock slopes above the ramps indicates that the ramps were formed by deposits of sand hillslopes after sliding. The process of a typical sliding sand hillslope (SSH) involves three major events: formation of sand due to weathering of rocks in upland areas and slopes, transportation of sand along the hillslope, and accumulation of sand at the toe of the slope. SSH commonly exists in the granitic mountains of Tibet and Xinjiang, however, it is one of the landforms rarely reported from mountain environments. This paper presents engineering and geological characteristics of SSHs based on field investigations and laboratory tests. This study investigated major damages of SSH and possible causes for intensive occurrence of SSH in this specific area. At the end of this paper, remedial measures to protect highways in this area are proposed.