泥石流堵河影响因素研究——以岷江上游为例

Study on Factors Affecting the River-blocking due to Debris-flow in the Upper Reaches of Minjiang River

以岷江上游为研究区,选取堵河型泥石流沟4条、堵塞型和不堵河型泥石流沟各2条,在详细分析和比较8条典型泥石流的流域特征、一次有代表性的泥石流过程的泥石流流体特征及沟口处主河特征的基础上,结合专家问卷调查,得出了与泥石流堵河关系较为密切的因素,它们是:泥石流规模、堆积区主河宽度、泥石流沟床比降、泥石流流量、入汇处主河流量、泥石流颗粒级配、入汇处主河比降、泥石流粘度、重度、泥石流沟与主河夹角、泥石流暴发频率等。

Taking the upper reaches of the Minjiang River as a study case, 4 debris-flow gullies of river blocking type, 2 debris-flow gullies of damming type and 2 of non-river-blocking type are selected for the study. By the analyzing and comparing characteristics of 8 debris flow basin, a representative flow course of each debris flow gully and the characteristics of main river where debris flow gullies converge, and in terms of experts＇ questionnaire investigation, it is known that the factors closely related to debris flows of river-blocking type are debris-flow scale, width of accumulation section of the main river, the gradient of gully-bed of debris flow, the debris-flow volume, the discharge of debris flow, the discharge of main river where the debris flows converge, grain grade of debris-flow, gradient of the main river where the debris flows converge, the unit weight of debris flow, the viscosity of debris flow, the angle of the gully to the main river and frequency of debris flows.