Dam Break-Induced Urban Flood Propagation Modelling with DualSPHysics: A Validation Case Study

Sustainable, safe and healthy growth of urban areas is currently achieved by a series of measures and initiatives, including the planning, management and mitigation of natural and anthropic possible hazards. Among potential menaces, extreme precipitation events of short duration, inducing severe urban flooding, may pose a significant threat for residents, especially if no counter-measures are planned to tackle with. Urban development, if not integrated with flooding mitigation strategies, generally goes with an increase of the impermeable surface, yielding a decreasing of infiltration and water evaporation as a result, and ultimately an increase of runoff peaks and a decrease of concentration times. These kinds of phenomena tend to worsen due to the ongoing climate change. In this framework, the sudden release of water through a simplified scaled urban configuration, following an abrupt dam breaching, is here numerically investigated. The open-source Lagrangian-based DualSPHysics solver was used for this aim. The aligned square city layout of 5 x 5 buildings case of Soares-Frazão and Zech (2008) was adopted as a validation case study. DualSPHysics post-processed free surface vertical profiles were compared with data recorded at 17 water-level gauges and numerical results of a finite-volume shallow water scheme, showing a reasonable agreement.