Lessons
Learned
The Izmit earthquake provides very valuable lessons about the construction practice in Turkey. These are;
- Building structures that comply with codes and specifications is not a requirement; it is a must. Many of the failures could have been avoided with proper design and construction.
- The choice of construction site is a crucial decision in designing for earthquake resistant structures. Constructing on liquefiable sand and silt deposits requires additional measures to be taken (such as pile or flat foundations, seismic isolators, improving soil conditions using chemicals, etc.).
- The performance of structures depends highly on the type of structural system chosen. 95 percent of residential structures in Turkey are built with similar structural design, consisting of reinforced concrete framing. New construction methods, such as tunnel-type-molding or use of steel structures, are proven to be more effective in such damage prone areas. Such methods should be promoted and adopted.
Conclusions
The Izmit earthquake proved, once again, the importance of building safe and reliable structures in areas that are susceptible to earthquakes. By using proper choice of materials and design, make use of specifications and codes and take the necessary precautions for soil conditions we could achieve that goal in seismically active areas.
References
U.S. Geological Survey, 1999,
“Scientific Expedition to Turkey: Field Investigations of the 1999 Izmit
Earthquake”, < http://quake.wr.usgs.gov/study/turkey/index.html
>
Bogazici University Kandilli Observatory and Earthquake Research Institute, 1999, Kocaeli Earthquake Information Center, < http://tanasi.gg.utk.edu/izmit.html >
Rob Westaway, 1994, "Present-day kinematics of the Middle East and eastern Mediterranean", Journal of Geophysical Research, Vol. 99, pp. 12,071-12,090
Ambraseys, N.N., 1970, “Some
characteristic features of the Anatolian fault zone”, Tectonophysics 9, pp.
143¯165
Koçyigit, A. and Beyhan, A., 1998, “A new intracontinental transcurrent structure: the Central Anatolian Fault Zone, Turkey”, Tectonophysics 284, pp. 317¯336
Bardet, J. P., 1999, “Geotechnical findings from the 1999 Kocaeli, Turkey, earthquake and the 1999 Chichi, Taiwan, earthquake”, EERC Library, Call No:(705.85/1999/I78)
Celebi, Mehmet, 1999, “Strong-motion, site-effects and hazard issues in rebuilding Turkey: in light of the 17 August, 1999 earthquake and its aftershocks”, EERC Library, Call No: (705.85/1999/I78)
Tezcan SS, Ipek M, 1996, “A reconnaissance report: 1995 Dinar, Turkey, earthquake”, Engineering Structures 18: (12) pp. 906-916
Grosser H, Baumbach M, Berckhemer H,
et al., 1998, “The Erzincan (Turkey) earthquake (M(s)6.8) of March 13, 1992
and its aftershock sequence”, Pure and Applied Geophysics 152: (3) pp.
465-505.