The characteristics and control of the low frequency debris flow——Taking the Chayuan gully debris flow Wenchuan County, Sichuan Province as a example
Jinshan Zhang, Xingju Shen · The Chinese Journal of Geological Hazard and Control · 2005
The low frequency debris flow refers to the debris flow which occurs once for more than thirty years. Because of the low frequency and short of people's cognition, it always causes huge harmness comparing with other debris flows. Taking the Chayuan gully debris flow, Wenchuan County, Sichuan Province occurring on August 9,2003 as an example, this paper discussed the characteristic of the low frequency debris flow from the material source and the reason caused by human being and nature. At the same time, the velocity, the discharge and the density were calculated by the way of configuration investigation and weighing density. Aiming at the characteristic of the low frequency, the large disaster and the concealment, considering the needed fund and the importance of the protected object, some measures of precaution and control were set up such as division of risk analysis of debris flow, reservation of water and soil of small watershed, popularization the knowledge of averting disaster and strengthening surveillance and prediction, Which could provide the use of reference for the harness of the low frequency debris flow area.