计算“7·10”四川省汶川县连山大桥泥石流运动参数,分析泥石流运动与堵溃特征,揭示“7·10”连山大桥泥石流灾害成因,为合理选择泥石流治理方案提供科学依据。通过对连山大桥泥石流灾害进行的现场勘查、泥石流运动特征参数(泥石流容重、流速、流量、一次总量及冲击力)的计算、沟道泥石流堵溃特征的分析,结果表明连山大桥泥石流为黏性泥石流,主沟泥石流流速为4.2~9.3m/s,配方法计算得到的泥石流峰值流量(41.8m3/s)远小于形态调查法得到的流量(出山口176.4m3/s),百年一遇泥石流一次总量为6620m3,块石最大冲击力为4955kN。“7·10”连山大桥泥石流灾害主要成因为泥石流在运动过程中发生2次堵溃,泥石流流量剧增。针对连山大桥泥石流沟现状,进行泥石流工程治理和监测预警工作是十分必要的。
The paper calculates the dynamic characteristic parameters of the Lianshan bridge debris flow outbreaking disasters on July 10, 2013 in Wenchuan, Sichuan. It analyzes the dynamic characteristics and the block and burst characteristics of the debris flow gully. And it reveals the cause of the debris flow disaster. These researches provide scientific basis for selecting the prevention measures of the Lianshan bridge debris flow. The paper calculates the dynamic characteristic parameters of the debris flow including density, velocity of debris flow, flow of debris flow, total volume and impact analyzes the changing process of the debris flow, and studies the blocking and burst characteristics of the debris flow. The results show that the debris flow of the Lianshan bridge is viscous. The velocity of the debris flow is 4.2--9.3 m/s. The calculated peak flow rate of the debris flow (41.8 m3/s) by the rain flood method is far less than that by the investigation method (176.4 ma/s). The total volume of the debris flow is 0. 662 5〈 104 ma. The maximal impact of thedebris flow is 4955 kN. The main cause is that process of the debris flow movement, and the current situation of the Lianshan bridge debris the gully has tWO obvious blocks and bursts in the flow of debris flow has increased. According to the flow gully, the work of the debris flow engineering management and monitoring and early warning is very necessary.