标题:Analysis of the Tangjiaxi landslide-generated waves in the Zhexi Reservoir, China, by a granular flow coupling model
作者:Bolin Huang, Yueping Yin, Shichang Wang, Jianmin Tan, and Guangning Liu
期刊:Natural Hazards and Earth System Science
卷: 期:17 页:657-670
DOI:10.5194/nhess-17-657-2017
出版时间:2017
摘要:
A rocky granular flow is commonly formed after the failure of rocky bank slopes. An impulse wave disaster may also be initiated if the rocky granular flow rushes into a river with a high velocity. Currently, the granular mass–water body coupling study is an important trend in the field of landslide-induced impulse waves. In this paper, a full cou pling numerical model for landslide-induced impulse waves is developed based on a non-coherent granular flow equation, i.e., the Mih equation. In this model, the Mih equation for continuous non-coherent granular flow controls movements of sliding mass, the two-phase flow equation regulates the in teraction between sliding mass and water, and the renormal ization group (RNG) turbulence model governs the move ment of the water body. The proposed model is validated and applied for the 2014 Tangjiaxi landslide of the Zhexi Reser voir located in Hunan Province, China, to analyze the char acteristics of both landslide motion and its following impulse waves. On 16 July 2014, a rocky debris flow was formed after the failure of the Tangjiaxi landslide, damming the Tangjiaxi stream and causing an impulse wave disaster with three dead and nine missing bodies. Based on the full coupling numeri cal analysis, the granular flow impacts the water with a max imum velocity of about 22.5 m s−1 . Moreover, the propaga tion velocity of the generated waves reaches up to 12 m s−1 .The maximum calculated run-up of 21.8 m is close enough to the real value of 22.7 m. The predicted landslide final de posit and wave run-up heights are in a good agreement with the field survey data. These facts verify the ability of the pro posed model for simulating the real impulse wave generated by rocky granular flow events.