Citation:
 | paper_55_veesd-2013.pdf | 1.75 MB |
Abstract:
The seismic history of the centre of Athens may be revealed through the response of its classical and
neo-classical columns to ambient noise and earthquake shaking. Detailed ambient vibration surveys in two cases
are presented: a) the two choragic columns on the south slope of the Acropolis, above the Monument of
Thrasyllos, constructed in the late classical-early Hellenistic era (3rd–1st century B.C.), with an original design
and a high constructive quality (13 April – 10 May 2011) b) the statue of Apollo (mid-19th century), on the right
side of the Academy of Athens building prostyle, mounted on a column in the Ionian rhythm (5-13 March 2008).
In the first (Acropolis) case, ambient noise measurements were performed with seven digital 3-component
seismographs at the top and the base of each column, as well as at three nearby reference sites. In addition,
forced vibration tests at the top of each column were also conducted. In the second (Academy) case, five
instruments of the same type were installed at the base of the column, the base of the statue, with reference sites
at the two corners of the Academy building and the garden at the back side of the building. For both cases, the response spectra and amplitude ratios were computed, providing information on the soil-column interaction, as well as the characteristic frequencies of spectral ratios peaks.