Estimation of debris flow sedimentation volume through numerical modelling

Abstract

Implementation of potential debris flow hazard in Malaysia has been conducted by JabatanKerja Raya (JKR) in 2011. However, evaluation of this hazard level cannot deny the consequent to the nearest facilities. Thus, run-out analysis based on numerical modelling is easiest and competent way to evaluate the risk level. This paper presents a study on debris flow sedimentation volume with and without sabo dam by numerical simulation using Kanako 2D software. Kanako 2D software is widely being used in Japan and it is equipped with graphical user interface (GUI). A crossed verification upon numerical modelling and actual field data collection, and mitigation situation model that include sabo dam has been conducted. Results showing that Kanako 2D software have a precise output where the sedimentation volume is slightly higher around 5-15 %. It also proven that sabo dam can reduce the impact of debris flow because it can bear the sedimentation volume about 91%. In speeding up the process of setting landform in Kanako 2D, it recommended to use GIS to generate appropriates data. Thus, a laser scanning of topographical data is required.