StEER: 2023 Ecuador Earthquake Preliminary Virtual Reconnaissance Report (PVRR)

On March 18, 2023, a Magnitude 6.8 earthquake occurred in Ecuador, which caused substantial damage to the cantons and cities within the three provinces of El Oro, Guayas, and Azuay nearest to the epicenter. At least 45 aftershocks were reported one day after the event, with the largest aftershock reaching a magnitude of 4.9. The largest peak ground acceleration was 0.32g for the north-south component recorded at Machala, approximately 53 km from the epicenter.
Fortunately, the number of lives lost and injuries from this earthquake were remarkably low, resulting in only 14 deaths and 494 injuries in comparison to the 2016 event. Still, the Balao earthquake caused damage to over 900 structures. In general, engineered structures (commercial, and government buildings and multi-family residential structures) performed well, exhibiting only non-structural damage. The earthquake drew attention to the vulnerability of historic buildings, and non-engineered (mainly residential) structures built using flexible reinforced concrete frames in combination with stiff infill masonry.
The earthquake highlights the need for more research into retrofit solutions that address the incompatibility of stiff brick/concrete infill masonry and reinforced concrete frames. This is particularly important for non-engineered buildings where inadvertent design choices yield extremely flexible reinforced concrete frames. New construction should encourage the use of alternative structural systems using lighter cladding materials that retain some aesthetic characteristics that make these stiff infills appealing (moderate cost, simple construction methods, and acoustic isolation), but are more compatible with the displacement tolerances of structural framing. This project encompasses the products of StEER's response to this event: Preliminary Virtual Reconnaissance Report (PVRR) and Media Repository.