Research on runout scale of gully type rainstorm debris flow based on numerical simulation

Journals

Title：
Research on runout scale of gully type rainstorm debris flow based on numerical simulation
Author：
Ze Tang, Jing Li
Author Affiliation：
Chengdu University of Technology, Chengdu 610059, China
Received：Oct.25, 2022

Accepted：Nov.21, 2022

Published：Dec.6, 2022

Abstract

The occurrence of gully type rainstorm debris flow will pose a serious threat to people’s lives and properties. The runout scale of debris flow is an important parameter to estimate disaster losses, so it is necessary to research the runout scale of gully type rainstorm debris flow. The numerical simulation method can be used to reproduce debris flow events. In order to simulate the runout process of gully type rainstorm debris flow after the earthquake and estimate the runout scale, the “8.14” catastrophic debris flow event occurred in Hongchun Gully, Yingxiu Town was taken as the research object, and the event was simulated with the R. Avaflow model to analyze the runout process of debris flow, and a contrastive analysis was conducted between the simulation results and the measured data of the debris flow accumulation fan. The simulation results showed that the maximum erosion depth of the “8.14” catastrophic debris flow in the Hongchun Gully was 1.27 m, which occurred at the corner of the main gully, and the total amount of debris flow was 780,000 m3 . The simulation results are close to the measured data. R. Avaflow model has good applicability and accuracy, and can be used to simulate and estimate the runout scale of rainstorm debris flow. The research results can provide an important reference for risk evaluation of rainstorm debris flow.

Keywords

Runout scale, rainstorm debris flow, R. Avaflow model, earthquake area.

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