NEGATIVELY BUOYANT DEBRIS IMPACT UNDER TSUNAMIS-LIKE CONDITIONS

Field surveys following major coastal disasters, such as the Chile tsunami in 2010 or the Tohoku tsunami in Japan in 2011, have pointed out the lack of resilience of coastal communities to such events and the need to better understand the risks associated with them (Takahashi et al. [2010]; Palermo et al. [2013]; Esteban et al. [2015]). While the primary cause of destruction during tsunamis remains associated with the hydraulic loads (hydrostatic, hydrodynamics, wave impact, etc.), it has been demonstrated that debris loading is also a major cause of damage on structures, mainly through debris impact and damming (Yeh et al. [2014]). In the past decade, multiple studies have addressed debris transport and loading in extreme events (Shafiei et al. [2016]; Ikeno et al. [2016]; Stolle et al. [2018]). However, those studies mainly focused on positively buoyant debris, like wood logs or empty containers, leaving a gap in knowledge. Indeed, Stolle et al. [2020], in a field survey following the Indonesian tsunami in 2018, identified the study of neutrally and negatively buoyant debris as one of five major needs in debris loading research, with even ASCE7-16 Chapter 6 containing limited recommendation on the load associated with those type of debris.