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A study with
a purpose to determine structural defects and faults:
The seismic risks of the existing buildings in various
districts of Istanbul, Turkey
Ali Koçak
Yıldız Technical University, Department of Civil
Engineering, Structural Engineering Division
Istanbul/Turkey. E-mail:
akocak@yildiz.edu.tr.
Tel: (+90212) 383 52 17, 0532 236
33 06. Fax: (+90212) 383 51 02.
Accepted 21 January, 2010 |
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Istanbul, a host of many different civilizations- being a
city of tourism, art, and culture, with a mega-city area of
5712 km2, having more than 1,000,000 buildings
with a population exceeding 10 million, has been exposed to
numerous earthquakes in its history and, has experienced
damaged extensively as a result of these earthquakes.
Istanbul was also affected by the recent August 17th Golcuk
and November 12th Duzce Earthquakes; and approximately
32,637 buildings were damaged. When the regional earthquake
accelerations were examined, it was observed not even a
design earthquake had occurred in Istanbul as a result of
these earthquakes. On the other hand, damage, destruction,
and the losses of life were observed to be more than the
expected values. As one can comprehend from these figures,
it can be stated that the building stock of Istanbul is
defective; and these buildings contain the risk of severe
damage or total collapse. It is considerably significant to
repair these negativities in the defective buildings and
remove the apparent defects for minimizing the risks.
Moreover, it was pointed out that a great danger awaits
Istanbul and the Marmara Region because of the seismic risk
and structural damage scenarios. Consequently, the
investigation of the present building stock of Istanbul
would help for better determination of earthquake scenarios
for Istanbul and the Marmara Region. A detailed examination
was conducted on a total of 467 buildings with reinforced
concrete or masonry structural systems, from 23 different
districts of Istanbul, and the results obtained were
evaluated in this study. The damage conditions of the
buildings, their suitability to the original project,
concrete strength values, reinforcement conditions, project
and building defects, and other architectural and structural
system faults, not suitable as regards to the seismic
design, were determined. As a result, apparent defects and
faults for the investigated buildings were marked.
Key words:
Earthquake, present building stock, structural defects, risk
analysis, Marmara region. |
