Debris Flow Modelling Incorporating Structural Mitigation Measures with FLO-2D

Abstract

Debris flow is common in season of significant rainfalls, an area with this recurrent problem is Huaycoloro river basin in Lurigancho district, Lima-Perú, this paper objective is modeling Huaycoloro river basin debris flow impact analysis of the structures in these natural disasters with FLO-2D software. Methodology to analyze it began with geomorphology and topography input data. Model was calibrated according to data flood signs of last debris flows events in study area. Using FLO-2D, this is modeled for 500 years return period and according to results optimal location of structures were analyzed at different location scenarios. Pre-dimensioning of structures was done in base of impact force produced by flow for aforementioned return period with aim of location them at specific points where depth developed by flow is important, and this way, incorporate structures to digital elevation model and as results allowed us to reduce 1.4 meters depth and 0.7 m/s of velocity in all system compared to initial scenario without structures. In conclusion structures allows us to improve disaster mitigation conditions caused by debris flows.