基于灾害演化网络的泥石流风险评估方法研究

Research on Risk Assessment Method of Debris Flows Based on Disaster Evolution Network

为准确地进行泥石流灾害演化风险评估、关键节点的定量识别,构建了基于灾害演化网络、结合随机过程的风险评估模型。通过构建灾害演化网络分析灾害链演化规律和灾害节点的影响程度,引入概率随机分布描述致灾节点发生概率和灾害节点的可能性,并将致灾节点发生概率,灾害节点发生后的影响程度和发生可能性进行耦合,识别灾害网络演化关键节点。将该方法应用于四川汶川板子沟地区泥石流后,结果表明:在四川汶川板子沟地区泥石流灾害演化中,风险控制的关键点分别是阻止泥石流入侵居民聚集地,减少交通受阻和救援受阻,与实际救援现场情况相符。研究结果可以为更有效地进行泥石流灾害应急救援提供一定的理论支撑。

Aiming to perform risk assessment of debris flow hazard evolution and quantitative identification of key nodes accurately,and by incorporating with stochastic process,a risk assessment model is constructed based on the hazard evolution network.By constructing a disaster evolution network to analyze the evolution law of disaster chain and the influence degree of disaster nodes and introducing probabilistic random distribution,the probability of occurrence of disaster-causing nodes and the likelihood of disaster nodes are described.Besides,the probability of occurrence of disaster-causing nodes,the degree of influence and the possibility of occurrence of disaster nodes are coupled to identify the key nodes of disaster network evolution.After applying it to the debris flow in Banzi catchment,Wenchuan County,Sichuan Province,the results show that stopping the debris flow from invading the residents'gathering place and reducing the traffic obstruction and rescue obstruction are the key points of risk control in the debris flow disaster evolution in Banzi catchment,which is in line with the situation of the actual rescue site.Therefore,the results of the study can provide certain theoretical support for more effective debris flow disaster emergency rescue.