Site response analysis of an urban area: A multi-dimensional and non-linear approach

• Published in: Soil dynamics and earthquake engineering (1984) 2018-06, Vol.109, p.33-45
• Main Authors: Falcone, Gaetano, Boldini, Daniela, Amorosi, Angelo
• Format: Article
• Language: English
• Subjects: 3-D technology; Amplification; Calibration; Constitutive models; Earthquakes; Finite Element method; Horizontal orientation; Iron; Mathematical models; Multi-dimensional approaches; Non-linear analysis; Nonlinear response; Numerical simulation; Seismic engineering; Seismic response; Seismic site response; Site effects; Soil erosion; Three dimensional models; Urban areas; Velocity
• ISSN: 0267-7261; 1879-341X
• DOI: 10.1016/j.soildyn.2018.02.026

This paper critically examines the numerical predictions of the seismic site response of both ideal and real cases as obtained by means of mono- and multi-dimensional Finite Element (FE) approaches. Ideal case-studies are first considered, aiming at validating the adopted numerical approach against existing analytical or simple numerical solutions. Then a three dimensional model of the Bovino urban area, located in southern Italy, was generated taking into account the real site conditions. Numerical analyses were thus carried out adopting a non-linear elasto-plastic soil constitutive model implemented in a commercial FE code. The following issues were investigated in detail: geometrical schemes, horizontal direction of the input motion, calibration of the constitutive model and non-linear soil response. Most of the obtained numerical results, presented in terms of amplification factors, indicate that larger amplifications occur when the more realistic multi-dimensional schemes are adopted as compared to the mono-dimensional ones. •Seismic site response analyses of the whole of urban area is a challenging task.•It should be tackled adopting multi-dimensional numerical approaches.•The higher is the dimensionality, the larger are the amplification factors in the valley and hill areas.•Non-linearity and plasticity can play a major role in the results.•Parasitic horizontal component is generated along the direction perpendicular to that of the input.