The 2009 L'Aquila earthquake (Italy): Its characteristics and implications for earthquake science and earthquake engineering

Moment büyüklüğü 6.3 olan L’Aquila depremi, İtalya’nın orta kesimindeki Abruzzi bölgesinde 6 Nisan 2009’da meydana gelmıştir. Deprem 294 kişinin yaşamını yitirmesine ve L’Aqulia kentinde ağır hasar meydana gelmesine neden olmuştur. Yazarlar, depremden hemen sonra depremin neden olduğu hasarı incelemişlerdir. Deprem normal bir faydan kaynaklanmış olup, özellikle fayın tavan bloğu üzerinde bulunan yerleşimlerde oldukça ağır hasarlara neden olmuştur. Bu çalışmada, L’aquila depreminin özellikleri ve deprem bilimi ve mühendisliğindeki önemi ile etkileri sunulmuştur. Bunun yanı sıra, yapılarda görülen ağır hasarlar ile bunların nedenleri sunulmuş ve tartışılmıştır. Ayrıca deprem tahmini yapıldığına ilişkin haberlerin doğruluğu bilimsel olarak incelenmiş ve bu öngörünün deprem tahmini için gerekli koşulları sağlamadığı görülmüştür. Gözlenen hasarlarının başlıca nedenleri, yapıların depreme karşı dirençlerinin düşük olması ve deprem yönetmeliklerinin uygulanmamış olmasıdır.

L'Aquila (Italya) depreminin özellikleri ve deprem bilimi ve mühendisliği açısından önemi

The 2009 L’Aquila earthquake that occurred in the Abruzzi region of Central Italy had a moment magnitude of 6.3. The earthquake caused the loss of 294 lives with casualties being particularly heavy in the old city of L’Aquila. The authors were able to investigate the damage caused by this earthquake soon after the event. The earthquake was caused by a normal fault and the heaviest damage was mainly on the hanging-wall side of the causative fault. This study describes the characteristics of this earthquake and its implications to earthquake science and earthquake engineering. Furthermore, the main causes of the heavy structural damage as well as the prediction of the earthquake are discussed. A close inspection of prediction claims indicates that the prediction did not really satisfy the requirements for earthquake prediction. The causes of the heavy damage were low seismic resistance of structures and lack of implementation of modern seismic design code.

PDF

___

Accelerometric National Network (RAN), 2009. Italian Department of Civil Protection, DPC, 2009. (http://www.protezionecivile. it/minisite/).

Ambraseys, N.N., 1988. Engineering seismology. Earthquake Engineering and Structural Dynamics, 17, 1-105.

APAT, 2006. Carta Geologica d’Italia alla scala 1:50.000 - Foglio n. 359 “L’Aquila”. S.EL.CA. Firenze.

Aydan, Ö., 1997. Seismic characteristics of Turkish earthquakes. Turkish Earthquake Foundation, TDV/TR 97-007, 41, İstanbul.

Aydan, Ö., 2000. An stress inference method based on structural geological features for the full-stress components in the earth’s crust. Yerbilimleri, 22, 223-236.

Aydan, Ö., 2007. The inference of seismic and strong motion characteristics of earthquakes from faults with a particular emphasis on Turkish earthquakes. Proceedings of the 6th National Earthquake Engineering Conference of Turkey, Istanbul, pp. 563-574.

Aydan, Ö., and Kawamoto, T., 1987. Toppling failure of discontinuous rock slopes and their stabilisation Journal of Japan Mining Society, 103(1197), 763-770 (in Japanese).

Aydan, Ö., and Kawamoto, T., 1992. The stability of slopes and underground openings against flexural toppling and their stabilization. Rock Mechanics and Rock Engineering, 25 (3), 143-165.

Aydan, Ö., and Ohta, Y., 2006. The characteristics of strong ground motions in the neighbourhood of earthquake faults and their evaluation. Proceedings of the Symposium on the Records and Issues of Recent Great Earthquakes in Japan and Overseas. EEC-JSCE, Tokyo, pp. 114-120.

Aydan, Ö., and Tokashiki, N., 2007. Some damage observations in Ryukyu Limestone Caves of Ishigaki and Miyako islands and their possible relations to the 1771 Meiwa Earthquake. Journal of the School of Marine Science and Technology, 5 (1), 23-39.

Aydan, Ö., and Kumsar, H., 2009. An experimental and theoretical approach on the modeling of sliding response of rock wedges under dynamic loading. Rock Mechanics and Rock Engineering (DOI: 10.1007/s00603-009-0043-3).

Aydan, Ö., Shimizu, Y., and Ichikawa, Y., 1989. The effective failure modes and stability of slopes in rock mass with two discontinuity sets. Rock Mechanics and Rock Engineering, 22(3), 163-188.

Aydan, Ö., Ulusay, R., Kumsar, H., Sönmez, H., and Tuncay, E., 1998. A site investigation of June 27, 1998 Adana-Ceyhan Earthquake. Turkish Earthquake Foundation, Report No. TDV/DR 006-03, İstanbul.

Aydan, Ö., Ulusay, R., Hasgür, Z., and Taşkın, B. 2000a. A site investigation of Kocaeli earthquake of August 17, 1999. Turkish Earthquake Foundation, Report No.TDV/DR 08-49, İstanbul.

Aydan, Ö., Ulusay, R., Kumsar, H., and Tuncay, E., 2000b. Site investigation and engineering evaluation of the Düzce-Bolu earthquake of November 12, 1999. Turkish Earthquake Foundation, Report No. TDV/DR 095-51, 307, İstanbul.

Aydan, Ö., Ulusay, R., and Atak, V.O., 2008. Evaluation of ground deformations induced by the 1999 Kocaeli earthquake (Turkey) at selected sites on shorelines. Environmental Geology, 54, 165-182.

Aydan, Ö., Ohta, S., and Hamada, M., 2009. Geotechnical evaluation of slope and ground failures during the 8 October 2005 Muzaffarabad Earthquake, Pakistan. Journal of Seismology (DOI:10.1007/ s10950-008-9146-7).

Bagh, S., Chiaraluce, L., De Gori, P., Moretti, M., Govoni, A., Chiarabba, C., Di Bartolomeo, P., and Romanelli, M., 2007. Background seismicity in the Central Apennines of Italy: The Abruzzo region case study. Tectonophysics, 444, 80-92.

Bertini, T., Bosi, C., and Galadini, F., 1989. La conca di Fossa-S. Demetrio dei Vestini. In: CNR, Centro di Studio per la Geologia Tecnica, ENEA, P.A.S.: “Elementi di tettonica pliocenico-quaternaria ed indizi di sismicita olocenica nell’Appennino laziale-abruzzese”. Societa Geologica Italiana, L’Aquila, pp. 26-58.

Bigi, G., Cosentino, D., Parotto, M., Sartori, M., and Scandone, P., 1990. Structural model of Italy and gravity map. CNR – Progetto Finalizzato Geodinamica, Quaderni de “La Ricerca Scientifica” 114 (3).

EC8 (CEN, Eurocode 8), 1994. Design provisions for earthquake resistance of structures. European ENV 1998. Comite Eurpeen de Normalisation, Brussels.

Devoti, R., Riguzzi, F., Cuffaro, M., and Doglioni, C., 2008. New GPS costraints on the kinematics of the Appeninnes subduction. Earth Planet Science Letter (doi: 10.1016/j.epsl.2008.06.031).

ERI, 2009. 2009 April 06 Central Italy Earthquake. Strong Motion Seismology Group. http://taro.eri.u-tokyo.ac.jp/ saigai/20090406eq/20090406.html.

Fukushima, Y., Tanaka, T., and Kataoka, S., 1988. A new attenuation relationship for peak ground acceleration derived from strong-motion accelerograms, Proceedings of the 9th World Conference on Earthquake Engineering 2, Tokyo- Kyoto, Japan, pp. 343-348.

HARVARD, 2009.Source process. http://www. globalcmt.org/cgi-bin/globalcmt-cgi-bin/

INGV, 2009. Special page on L’Aquila earthquake. http://www.ingv.it.

Kumsar, H., Aydan, Ö., and Ulusay, R., 2000. Dynamic and static stability of rock slopes against wedge failures. Rock Mechanics and Rock Engineering, 33 (1), 31-51.

Kuribayashi, E., and Tatsuoka, F., 1979. Brief review of soil liquefaction during earthquakes in Japan. Soils and Foundations, 15 (4), 81-92.

Joyner, W.B., and Boore, D.M., 1981. Peak horizontal acceleration and velocity from strong motion records from the 1979 Imperial Valley California Earthquake. Bullettin of Seismological Society of America, 71(6), 2011-2038.

Luca, de Luca, Marcucci, S., Milana, G.., and Sano, T., 2005. Evidence of lowfrequency amplification in the city of L’Aquila, Central Italy, through a multidisciplinary approach including strongand weak-motion data, ambient noise, and numerical modeling. Bulletin of Seismological Society of America, 95, 1469 - 1481.

Ohta, Y., and Aydan, Ö., 2007a. Integration of ground displacement from acceleration records. Proceedings of the JSCE Earthquake Engineering Symposium, Tokyo, pp. 1046-1051.

Ohta, Y., and Aydan, Ö., 2007b. An integration technique for ground displacement from acceleration records and its application to actual earthquake records. Journal of the School of Marine Science and Technology, 5 (2), 1-12.

Petitta, M., and Tallini, M., 2003. Groundwater resources and human impacts in a Quaternary intramontane basin (L’Aquila Plain, Central Italy). Water International, 28 (1), 57-69.

Port and Harbour Research Institute of Japan, 1997. Handbook on Liquefaction Remediation of Reclaimed Land. Balkema.

Tallini, M., Giamberardino, A., Ranalli, D., and Scozzafava, M., 2004a. GPR survey for investigation in building foundations. Proceedings of the 10th International Conference on Ground Penetrating Radar; Delft, Netherlands, pp. 395-397.

Tallini, M., Ranalli, D., Scozzafava, M., and Manocorda, G., 2004b. Testing a new lowfrequency GPR antenna on karst environments of Central Italy. Proceedings of the 10th International Conference on Ground Penetrating Radar; Delft, Netherlands, pp. 133-135.

Tokashiki, N., and Aydan, Ö., 2008. The stability assessment of natural rock structures in Ryukyu limestone. Proceedings of the 5th Asian Rock Mechanics Symposium (ARMS5), Tehran, pp. 1515-1522.

USGS, 2009. Magnitude 6.3 – Central Italy. http://earthquake.usgs.gov/

Yamanaka, Y., 2009. Central Italy earthquake. Nagoya University Earthquake research Center. http://www.seis.nagoya-u.ac.jp/ sanchu/Seismo_Note/2009/NGY15.html.