Engineering lessons from the 28 September 2018 Indonesian tsunami: debris loading

A field survey team went to Palu City, Indonesia in the aftermath of the September 28th, 2018 earthquake and tsunami to investigate its effects on local infrastructure and buildings. The study focused on the coast of Palu Bay, where a tsunami wave between approximately 2 and 7 m high impacted the local community as a result of several complex tsunami source mechanisms. The following study outlines the results, focused on loading caused by debris entrained within the inundating flow. Damage to timber buildings along the coast was widespread, though reinforced concrete structures for the most part survived, providing valuable insights into the type of debris loads and their effects on structures. The results of this survey are placed within the context of Canadian tsunami engineering challenges and are compared to the recently-released ASCE 7 Chapter 6 Tsunami Loads and Effects, detailing potential research gaps and needs. Key words: tsunami, natural disasters, field surveys, debris, coastal engineering, Indonesia. Une equipe d'etude sur le terrain s'est rendue a la ville de Palu, en Indonesie, a la suite du tremblement de terre et du tsunami du 28 septembre 2018, pour etudier ses effets sur les infrastructures et les batiments locaux. L'etude a porte sur la cote de la baie de Palu, ou une vague de tsunami d'environ 2 a 7 m de hauteur a touche la communaute locale en raison de plusieurs mecanismes complexes decoulant du tsunami. L'etude qui suit presente les resultats, en mettant l'accent sur le chargement cause par des debris entraines par le courant d'inondation. Les dommages causes aux batiments en bois le long de la cote etaient generalises, bien que la plupart des structures en beton arme aient survecu, ce qui a permis de mieux comprendre le type de charges de debris et leurs effets sur les structures. On presente les resultats de cette etude dans le contexte des defis d'ingenierie lies aux tsunamis au Canada et on les compare au chapitre 6 de l'ASCE 7, <>, publie recemment, qui decrit les lacunes et les besoins potentiels en matiere de recherche. [Traduit par la Redaction] Mots-cles: tsunami, catastrophes naturelles, etudes sur le terrain, debris, travaux maritimes, Indonesie.
Introduction On September 28th, 2018, at 18:02:43 local time, a Mw 7.5 strike-slip earthquake occurred along the coast of the Central Sulawesi province of Indonesia (Hui et al. 2018; USGS [...]