Abstract

The 2014 Iquique earthquake struck off the coast of Chile on April 1st with a moment magnitude of 8.2, as a result of thrust slip at shallow depths. The earthquake’s epicenter was located 34 km northwest of Iquique within a well-known seismic gap, and it generated a tsunami with a maximum run up of 4.4 m which affected local fishermen’s facilities in the cities of Arica and Iquique. While the overall response of the structural and geotechnical systems was satisfactory, there was evidence of liquefaction and lateral spreading in the quay walls of Iquique’s port and on the stream channel flowing under the Tana bridge. Overall, the seismic performance of the inspected bridges was satisfactory. Likewise, natural slope failures were observed along the coastal bluffs and interior creeks, and a large slope failure blocked the only route between the cities of Iquique and Alto Hospicio, causing mayor traffic congestions in the following days. Researchers from GEER-NSF and CIGIDENFONDAP deployed in the area to document the geotechnical aspects of this extreme natural event. This article summarizes the main findings and observations conducted by the reconnaissance teams with emphasis on the effects and consequences of the ground motion on the built infrastructure such as ports, bridges, retaining structures and cut slopes.