On the 4th of August 2020 early in the evening on an otherwise clear and typical summer day in Beirut, an explosion reported to be the third largest non-nuclear blast in history (releasing energy equivalent to a ML 3.3 earthquake) occurred in the port, around which the city was built over the past centuries. The nature of the event, its epicenter and the zones affected were unique and provided unprecedented opportunities to document the impact of mega-explosions on urban infrastructure.

What will be presented in this seminar, is an overview of the context, historical and geographical, and details re. the nature and power of the blast and the subsequent efforts to document the aftermath. These efforts in-volved multiple agencies, experts, volunteers and ordinary people. Our involvement in collaboration with col-leagues from UCLA and other institutions was to facilitate the collection of perishable engineering data of interest and to undertake a “first-level/gross” analyses of the gathered information. Two main categories of infrastructure systems were impacted — the Port of Beirut and the Beirut building stock. Within the Port, the explosion triggered a quay wall failure and flow slide, and strongly impacted grain silo structures that were only a few tens of meters from the point of initiation. Within the city, a combination of historical masonry structures and modern high-rise structures were impacted. Through a combination of in-person inspections and street-view surveys, data on structural performance and building façades was collected. Performance levels were classified according to standard procedures applied previously following earthquakes. The spatial distri-butions of these damage types and dependencies on source distance and line-of-sight and attempts at correlat-ing the observations to damage proxies produced by NASA-JPL based on satellite data will also be presented.

Dr Salah Sadek is a Professor at the Department of Civil and Environmental Engineering at the American University of Beirut. Dr. Sadek currently serves as the Associate Dean for the Maroun Semaan Faculty of Engineering and Architecture.
Dr. Sadek received his Bachelor’s Degree in Civil Engineering from the American University of Beirut and his M.S. and Ph.D. degrees in Geotechnical Engineering from the University of California, Berkeley in 1993.

He is the founding and current president of the Lebanese Geotechnical Engineering Society. Dr. Sadek’s current research and teaching interests are in the areas of Site Improvement and Alternative Foundation Systems, Energy Geotechnics, and Geo-hazards.