Complex Site Effects in Thessaloniki (Greece): I. Soil Structure and Comparison of Observations with 1D Analysis

• Published in: Bulletin of earthquake engineering Vol. 2; no. 3; pp. 271 - 290
• Main Authors: Raptakis, Dimitrios, Makra, Konstantia, Anastasiadis, Anastasios, Pitilakis, Kyriazis
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01-01-2004
• Subjects: Geological structures; Geology; Geophysics; Geotechnics; Ground motion; Grounds; Mathematical models; Seismic phenomena; Soil (material); Soil structure; Studies; Subsoils; Surface waves; Time domain; Two dimensional; Greece; Greece, Kentriki Makedonia, Former Yugoslav Republic, Thessaloniki
• ISSN: 1570-761X; 1573-1456
• DOI: 10.1007/s10518-004-3799-6

This paper presents a 2D model of the geological structure of Thessaloniki city and results of empirical and theoretical approaches for the evaluation of site response due to complex site effects. The construction of the 2D model is based on the available geophysical and geotechnical data in terms of the most important parameters needed to model site response. The well-known subsoil structure, despite the existence of some local uncertainties, gave the possibility to correlate the geometry and the dynamic properties of the 2D model with the results of site response determined from the analysis of one event in frequency and time domains and 1D numerical modelling. The study of site response shows the effect of the lateral variations on ground motion and suggests that the contribution of locally generated surface waves to the resonant peak may be important. In this case history, the limitations of the 1D approximation to simulate ground motion under complex soil conditions in both frequency and time domains are also shown. This paper lays the ground for a companion article dealing with 2D site effects.