Research On Monitoring And Waring System For Debris Flow

Debris flow is one of the main mountain hazards in China and it causes greateconomic loss and casualties every year. Especially after512WenChuanEarthquake, most surface of SiChuan mountains had been shattered and debris flowsource supply increased, the debris flow occurs more frequently.In this paper, Township of WenChuan County Liujiagou gully was selected as theresearch object. In the process of research, field survey for debris flow and dateanalysis are used, combined with debris flow study at home and board, to analysisthe LiuJiaGou debris flow. And according to the result of field survey, the debris flowwarning model for LiuJiaGou was established. It’s significant theoretical and practicalvalue on LiuJiaGou debris flow monitoring and early warning model. To completethis study,the works of this paper is follows:1. In order to get the formation characteristics of LiuJiaGou debris flow gullyaccurately, the geological background of the LiuJiaGou was surveyed in field. And thegeological environments, such as morphology, lithology, geological structure,earthquake, meteorological and hydrological, etc. are analyzed.2. Because of the facilities for debris flow observation is limited, the motionfeature of the debris flow cannot be directly surveyed. So we,based on the analysis ofresults by filed surveyed,analyzed and calculated the velocity of the debris fluid，theimpact force of debris fluid, etc. This date can be used to as the results in managementengineering for this debris flow gully.3. According to field investigation data, combined with previous research resultsof debris flow, we use the numerical theory and hierarchical analysis method to rankthe risk of the debris flow. According to the risk assessment model, we selected11evaluation factors, including24-hour maximum rainfall, dynamic reserves of soil andetc. And combined with the experts and scholars suggestions, we determine the ratioof the relative importance of each factor and score the factors. The LiuJiaGou debrisflow was ranked moderate risk on the basis of the result of the score. 4. According to the results, combined with the characteristics of the LiuJiaGoudebris flow, we determine the methods and means of monitoring warning in singlemode and multi-warning system. Including①critical rainfall warning indicators;②debris flow mud depth level critical warning indicators;③Multi-warningmonitoring collaborative work processes.5. Four debris flow warning levels was established based on the early warningsystem. Different early warning information will be noticed to the residents accordingto the warning level. And three departments, undertook the task that is to publish theearly warning information, was established as the early warning system.6.By monitoring the process of “710” debris flow, the early warning system andthe management system are proved to be reasonable.