Liquefaction and Non-liquefaction Cases from the Mataquito Bridge, Chile, after the Mw 8.8 (2010) and Mw 6.6 (2019) Earthquakes

Abstract

This paper describes field investigations and soil foundation performance of the Mataquito Bridge with respect to the 2010 Mw 8.8 and 2019 Mw 6.6 Chilean earthquakes. The Mataquito Bridge was constructed at the site prior to both earthquakes using a pile foundation designed against liquefaction and lateral spreading. The foundation system performed correctly during both earthquakes, and in the case of the 2010 event it withstood surface manifestation of liquefaction and lateral spreading loads. Different liquefaction severity indices are used to assess the liquefaction hazard with data from in-situ measurements. This paper provides a collection of data (Vs, CPT, SPT) for liquefaction and non-liquefaction cases at the same site under two different levels of shaking, and valuable case history data for future triggering and severity index models. Lateral displacements are also calculated and compared with those observed on the field after the 2010 earthquake.