Fluvial Fan Process due to Swing Phenomena

Abstract

To analyze the fan formation process due to swing phenomena of the debris flow, the authors performed a numerical simulation of debris flow by means of depth integrated two dimensional governing equations of solid-water mixture and the bed shear stress formula characterized by yield and the fluid type shear stress. In this research, the debris flow phenomena and fan formation processes are studied as the test case applied in the Chacaito Creek located in the metropolitan urban area of Caracas city, Venezuela. The results of 2-D numerical simulations confirmed the influences of swing phenomena in the temporal variations of the morphology of debris fan. Likewise, the research demonstrates that fan formation processes in successive numerical simulations have variations in the spatial distribution of the sediment deposition due to changes in the debris flow directions caused by the topographic conditions at the fan head and the swing phenomena.