The dynamic monitoring of an elevated water reservoir, employing a biaxial optical accelerometer, is described. The structure natural frequencies were measured with an error of 0.06 %, when compared with the values attained from seismograph.
Agradecimentos: This research was partially funded by the São Paulo Research Foundation (FAPESP) (#2014/50632-6). J.H.O. gives thanks to CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) for financial support