Method for Developing Hazard Map Due to Debris Flow Prediction (PAP014408)

Código

PAP014408

Autores

Rosiret Escalona Martinez, Atsuhiro Yorozuya, Shunji Egashira, Yoichi Iwami

Tema

Land use and Floods, landslides and erosion

Resumo

This study aims to propose a method for developing hazard maps due to debris flow based on numerical simulations with 1-D and 2-D debris flow models. The 1-D numerical simulations were conducted to investigate variables responsible to debris flow volume. 2-D numerical simulations were performed to analyze the debris flow behavior over ideal debris fans, as well as to obtain basic information necessary for preparing a hazard map. The 1-D numerical results show that the debris flow volume increases with supply water discharge, length of stream reach and bed slope in condition that potential erosion depth is large enough for sediment transport capacity of debris flow, and that the debris flow size reaches its equilibrium after flowing over some distance. The 2-D numerical results show that debris flow spreading increases longitudinally with the fan slope and in addition, a hazardous area, which is usually considered as deposition area, is reproduced in response to the ground surface topography of the fan, although there is an artificial channel for draining flood water.