Study On The Auto Monitoring And Early-warning Of Debris Flow Of Wangmo River In Guizhou Province

As a sudden flood in ravine, debris flow frequently threatened hilly area in China and caused huge economic losses. Wangmo county has vast mountain area and complex terrain in Guizhou province. In the year of 2006, 2008 and 2011, the basin of Wangmo river of the county had been affected by extremely rainstorm and caused major mudslide and flush flood. The mudslide had caused huge losses in Wangmo County. The work of control debris flow is imminent.And the monitoring and early warning of mudslide is the most important of the control. This thesis taken debris flow of Wangmo river as the research object, based on the research results of monitoring and early warning of mudslide, the basin had been studied, the information of debris flow had been gathered, the development characteristic and formation of rock-mud flows had been analyzed. And the targeted monitoring plan of Wangmo river mudslide had been studied and designed. With the four-level warning method of debris flow, the early warning index and system had been initially formulated. Finally, the auto monitoring and early warning system of Wangmo river mudslide had been built. The following results:(1) Based on investigations, the development characteristic and formation of rock-mud flows had been analyzed. Meanwhile, the characteristics of Wangmo river mudslide had been summarized. The mudslide had small-scale mudslides in many places, the longer flow distance and big scale.(2) By analyzed of the key parameters of mudslide in the stage of formation, movement and disaster, with the specification of monitoring technology of debris flow, there are seven kinds of parameters and monitoring instruments had been determined. The parameters are rainfall parameters, soil moisture content, pore-water pressure, water level, current velocity, infrasound and image. According to the the characteristics of mudslide, the auto monitoring plan had been designed.(3) By analyzing the historical information of Wangmo river mudslide and gathering the references of debris flow monitoring, the thresholds of parameters had been slated. Based on the 60%, 80%, 90% and 100% of the thresholds, the four-level early warning index of rainfall, soil moisture content, pore-water pressure, water level, current velocity and infrasound had been slated. And the video monitoring method had been formulated. On this basis, the early warning framework of Wangmo river mudslide had been built.(4) By studied the formation of auto monitoring and early-warning system, combining the monitoring plan, early-warning index and framework, the auto monitoring and early-warning system had been built which consisted of five subsystems. They are sensor system, auto collecting and transmitting system, auxiliary and power system, gathering and analysing system, warning and decision platform. Initial results have been achieved by this system.