GEODYNAMICAL HAZARDS ASSOCIATED WITH LARGE DAMS

design parameters and criteria and for all other dynamic
investigations in earthquake engineering. Without such data
all investigations and analysis that follow would be based on
assumptions. The irregularity in earthquake occurrence
makes difficult the possibility to obtain immediately the most
useful data.
One of the possible ways to solve these problems is to
establish a network of a greater number of instruments for
recording ground motion and response of structures during
strong earthquakes. The main objective in seismic monitoring
of structures (high-rise buildings, dams, power plants,
bridges etc.) is to facilitate response studies that lead to
improved understanding of the dynamic behavior and
potential for damage to structures under seismic loading.
TESTING THE TRIGGERING OF STRONG
EARTHQUAKES IN DAM AREAS- AN APPLICATION
IN POLYPHYTO DAM, GREECE
Gerassimos A. Papadopoulos
Institute of Geodynamics, National Observatory of Athens,
11810 Athens, Greece
g.papad@ egelados.gein.noa.gr
ABSTRACT
A stochastic approach is proposed for testing the random or
non-random occurrence of strong earthquakes in dam
regions. An appropriate probabilistic model for the
earthquake time distribution in the dam region is adopted
and, then, the probability is calculated for the occurrence by
chance of particular earthquake(s) within particular time
interval(s) counted from the impoundement or significant
water level variations in the dam. The application in the
Polyphyto dam (NW Greece) the impoundement of which
took place in 1974, showed that the occurrence of the strong
earthquakes of 25 Oct 1984 (Ms=5.5) and 13 May 1995
(Ms=6.6) is non-random at the 0.93 probability level.
A STUDY OF THE RELATION BETWEEN THE MAY
13, 1995 KOZANI-GREVENA (NW GREECE)
EARTHQUAKE AND THE POLYPHYTO
ARTIFICIAL LAKE