Structural monitoring of a curve portion of an elevated railroad including the effects of the 19 September 2017 earthquake

Abstract

This article presents the most significant structural response parameters of a railway system analyzed with data gathered during 5 years. The structure is the instrumented curved portion of an elevated railroad that consists of a simply supported beam resting on cantilever columns on soft soil. A monitoring system was implemented to determine, within a few minutes, a preliminary structural state analyzing ambient vibration or seismic events. To assess the state of health of the structure, the response obtained from the seismic events, applying the proposed methodology, is compared with that obtained from controlled field tests conducted at the end of its construction and compared with design values. The monitoring system’s results showed minimal frequency variations caused by external works and a transitory variation of the fundamental frequencies during the 19 September 2017 great earthquake that, however, did not affect the structural integrity. The warning system showed acceptable performance, and only suggested checking the support beam-column condition.