Bucharest City Hall is a
6 floor masonry building having a plan area of 3800 square meters. It was
built in 1912 and enlarged in 1950. For its retrofitting, Alga and Freyrom,
the subsidiary of Freyssinet in Romania, supplied 262 rubber isolators
dia.1000 and 1050 mm and 36 viscous dampers of 1750 kN. The design movement
of all the devices is equal to +/-700 mm, with sesmic velocity of 1,5 m/sec.
Both the rubber isolators and the viscous dampers have been successfully
tested at the maximum design velocity at the University of California Laboratory
located in San Diego (USA). The devices have been designed according to
the European Standard EN15129. Freyrom's scope also includes loading and
load transfer using flat jacks. Base isolation is often the best solution
for the seismic protection of historic buildings in highly seismic areas,
such as Romania. |