Experiments research on anti-scourability of the big-sized samples from loess caves

摘要

Soil erosion resistant capacity is divided into the soil anti-erodibility and the soil anti-scouribility. Tunnel erosion belongs to one of specific soil erosions, which is largely distributed in loess areas. Tunnel erosion in the loess not only directly causes a large amount of materials loss, but also indirectly brings many engineering geological problems associated with landslides, road bases and dams. This paper, by means of field experiments of big-sized samples from loess cave, analyzing scouring process of big-sized original state loess, which divided into three periods: a period of rapid erosion, an erosion slow-down period and a period of steady erosion, discussing influence factors of loess erosion rates, and calculating the comprehensive index of soil anti-scourability, that is, loess erodible coefficient. Results of this study can play a significant role on quantizing analysis on the formation and evolution of loess caves, further understanding of tunnel erosion processes of loess, also have practical value to direct soil and water conservation.