Seven years of continuous dynamic monitoring of baixo sabor dam

Abstract

The Baixo Sabor dam is a 123 meters high concrete arch dam located in the north of Portu-gal. After the performance of a forced vibration test, a quite unique experimental programme was initiated in the dam during the first filling of the reservoir, with the installation of a con-tinuous dynamic monitoring system in December 2015. The implementation of such a system aimed to study the evolution of the dam’s dynamic behaviour during the first filling, as well as to monitor its condition in the long-term through the development of vibration-based damage detection supported by robust operational modal analysis. After a description of the dam and the monitoring system, this paper presents an overview of the tools developed to perform the automated tracking of the dam’s modal parameters. Final-ly, using the database collected during the last seven years, the long-term evolution of the dam dynamic parameters is analysed, and their seasonal fluctuations interpreted. The even-tual occurrence of structural anomalies is evaluated after the minimization of the most influ-ential operational and environmental effects on the dam, such as temperature and the reservoir water level.