Soil-dependent topographic effects: A case study from the 1999 Athens earthquake

Assimaki, D; Kausel, E; Gazetas, G

dc.contributor.author	Assimaki, D	en
dc.contributor.author	Kausel, E	en
dc.contributor.author	Gazetas, G	en
dc.date.accessioned	2014-03-01T11:44:41Z
dc.date.available	2014-03-01T11:44:41Z
dc.date.issued	2005	en
dc.identifier.issn	8755-2930	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/37088
dc.subject	Case Study	en
dc.subject.classification	Engineering, Civil	en
dc.subject.classification	Engineering, Geological	en
dc.subject.other	Athens, Greece	en
dc.subject.other	Canyon ridge	en
dc.subject.other	Case study	en
dc.subject.other	Ricker wavelets	en
dc.subject.other	Approximation theory	en
dc.subject.other	Computer simulation	en
dc.subject.other	Finite element method	en
dc.subject.other	Rivers	en
dc.subject.other	Soils	en
dc.subject.other	Strain	en
dc.subject.other	Stress analysis	en
dc.subject.other	Earthquakes	en
dc.title	Soil-dependent topographic effects: A case study from the 1999 Athens earthquake	en
heal.type	other	en
heal.identifier.primary	10.1193/1.2068135	en
heal.identifier.secondary	http://dx.doi.org/10.1193/1.2068135	en
heal.language	English	en
heal.publicationDate	2005	en
heal.abstract	In the Ms 5.9 Athens, Greece, earthquake, surprisingly heavy damage occurred on the eastern bank of the Kifissos River canyon. To explore whether the particular topographic relief and/or the local soil conditions have contributed to the observed concentration and non-uniform damage distribution within a 300-m zone from the canyon crest, we conduct finiteelement analyses in one and two dimensions, using Ricker wavelets and six realistic accelerograms as excitation. The nonlinear soil response is simulated in the time-domain using a hyperbolic stress-strain model, and also approximated using a modified equivalent-linear algorithm; results obtained by means of the two methods are discussed in detail. Our simulations show that topographic effects are substantial only within about 50 m from the canyon ridge, materializing primarily because of the presence of relatively soft soil layers near the surface of the profile. We then introduce the concept of two-dimensional/one- dimensional response spectral ratio to describe the effects of topography as a function of local soil conditions, and suggest a frequency- and location-dependent topographic aggravation factor to be introduced for the modification of design spectra in a seismic code. © 2005, Earthquake Engineering Research Institute.	en
heal.publisher	EARTHQUAKE ENGINEERING RESEARCH INSTITUTE	en
heal.journalName	Earthquake Spectra	en
dc.identifier.doi	10.1193/1.2068135	en
dc.identifier.isi	ISI:000233816600002	en
dc.identifier.volume	21	en
dc.identifier.issue	4	en
dc.identifier.spage	929	en
dc.identifier.epage	966	en