A framework for designing slit-type barrier for debris-flow hazards

Abstract

In cases of debris-flow hazards, a high-speed flow would result in heavier casualties, due to insufficient time for evacuation, and more severe infrastructure damage. To attenuate the speed of the debris, we recommended using the slit-type open barrier as a mitigation method due to the ease of maintenance and reusability after mitigating a debris-flow hazard. In this study, a framework was developed to provide recommendations for the design of slit-type barriers. The framework consists of the following procedures: (1) debris-flow analysis using the DAN3D numerical program, (2) risk analysis using the debris-flow vulnerability analysis developed by Kang and Kim (2014), (3) selection of suitable barrier location based on debris-flow analysis and (4) design of slit-type barrier walls based on performance predicted using the FLOW-3D numerical program. A case study of the high-speed debris-flow hazard at Mt. Umyeon, Seoul, Korea in July 2011 was used to demonstrate the framework for designing slit-type barriers. Finally, the benefits and limitations of the developed framework are discussed.