Structural Assessment of Buildings after the Beirut Port Explosion: Analysis of the Data Collected by the Beirut Order of Engineers and Architects

Abstract

At 18:08 on the 4th of August 2020, a huge explosion occurred in the port of Beirut, Lebanon. The explosion was one of the strongest non-nuclear explosions ever recorded. As per USGS, the size of the blast was equivalent to an earthquake with local magnitude of 3.3. The deadly blast resulted in 220 deaths, and more than 7,000 injuries. After the blast, multiple efforts contributed to assessing the impacts of the blast on Beirut and to documenting the damage extent on Beirut’s buildings. Particularly, the Order of Engineers and Architects in Beirut (OEA) completed in-person structural investigations for five weeks and compiled surveys for about 2,500 Beirut buildings located within 3 km from the blast. The data collected by the OEA included a description of the general state of each building, the damages observed, the possible hazards and threats to public safety, and recommended actions (e.g., isolation of the building) to address potential threats, when needed. However, the OEA surveys did not assign a structural damage class to each building based on the structural damages that occurred. This work processes and analyzes the data collected by the OEA in order to consistently assign a structural damage class to each surveyed building based on procedures typically applied after an earthquake. The impacts of the explosion on the buildings assessed by the OEA range from full collapse to no structural damage. These spatially variable impacts are documented and analyzed to understand how the damage extent depends on the structural typology and age of the building, its distance from the blast, and whether or not it had a direct line of sight from the blast. The analysis of the data shows that the structures most damaged by the blast are stone masonry structures, older (gravity load designed) reinforced concrete buildings, and buildings located within 1 km from the blast. On the other hand, structures that sustained no to light damage are modern reinforced concrete structures and buildings located at distances greater than 1 km from the blast.