Ennouini Wafae
Evaluation of the influence of large wood transport on Flood Risk scenarios
Evaluation of the influence of large wood transport on Flood Risk scenarios
Abstract della ricerca
Evaluation of the influence of large wood transport on Flood Risk scenarios
Background nella ricerca
The presence of floating material is, on the contrary, normally disregarded, although it has been proved that it may significantly intensify the drawback of the flood. Vegetable materials, plastic objects and even cars or containers, which are initially located in the floodplains and may be entrained during the event, can flow on the water surface, moving down-stream and reaching urban areas. In presence of bridges or culverts, they may block openings and increase the backwater effect, already triggered by the presence of piers or of channel narrowing. Due to the above mentioned risk, a comprehensive approach for flood risk mitigation should be adopted with appropriate integrated management strategies that take into account the effect of woody material on hydraulic risk. All the processes that contribute to wood transport, like the estimation of the available wood volumes [15, 38] or the description of wood dynamics, should be carefully analysed to become part of an integrated approach. In this framework, experimental and theoretical insights for the assessment of large wood entrainment and transport are analysed in the literature, pointing out the connections between wood motion and the geometrical characteristics of logs, of channel hydraulics and of the river morphology. The interaction with in-stream structures, such as bridge piers, decks or retention structures, needs also to be considered for the evaluation of flood risk.
Obiettivi della ricerca
The development of a parallel numerical model that incorporates the motion of rigid bodies in the estimation of flood risk. It considers the two-dimensional transport of large wood, predicting their mode od motion (sliding,rolling,floating), their trajectories, orientation and the interaction with other bodies or with inline structures.
Metodi
Two ways coupling of the Eulerian solution of the shallow water equations and the Lagrangian model of the transport of large wood
Risultati
Achieved: developement of a numerical model that incorporates the motion of rigid bodies in the estimation of flood risk. It considers the two-dimensional transport of large wood, predicting their mode od motion (sliding,rolling,floating), their trajectories, orientation, the model was applied to flume test case studies and to a real case study (tagliamento river) and compared the results to real data servey tracked using a gps . Expected: Experimental campaign at Unical and the calibration of the Rolling/Sliding mode, parallelizing the code to optimize the time cost and integrating a rain-on-grid (direct rainfall to the cells) model to take into account the incipient of motion in the case of overland flow.