Amplification pattern of 2D semi‐sine‐shaped valleys subjected to vertically propagating incident waves

Abstract

SUMMARYThis paper presents the preliminary results of an extensive numerical parametric study on seismic behaviour of two-dimensional semi-sine-shaped valleys subjected to vertically propagating incident in-plane compression and shear waves. The medium is assumed to have a linear elastic constitutive behaviour. All calculations are executed in time-domain using the direct boundary element method. Clear perspectives of the amplification patterns of the valley are presented by investigation of the frequencydomain responses. It is shown that wavelength, site geometry and in a less order of importance, wave type and material parameters, are the independent key parameters governing the valley's amplification pattern. Some simple rules are obtained which could be used in seismic microzonation and seismic design of structures founded inside the valley.

Estimation of topographical effects at Narni ridge (Central Italy): comparisons between experimental results and numerical modelling

“…The 2D simulations were performed by using the HYBRID code, developed by Kamalian et al (2003) and already tested for several examples of site response concerning canyons and hills (Kamalian et al 2006(Kamalian et al , 2007. To further verify the capability of HYBRID, we investigated the response of Narni ridge in correspondence of two transversal profiles (P1 and P2, see Fig.…”

“…Spudich et al 1996;Le Brun et al 1999;Massa et al 2004Massa et al , 2010Buech et al 2010;Pischiutta et al 2010;Marzorati et al 2011) and2D and/or 3D numerical modeling (i.e. Boore 1972;Bard and Tucker 1985;Géli et al 1988;Sanchez-Seisma 1990;Sanchez-Sesma and Campillo 1991;Chavez-Garcia et al 1996;Komatitsch and Vilotte 1998;Paolucci 1999Paolucci , 2002Kamalian et al 2006Kamalian et al , 2007.…”

A BEM investigation on the influence of underground cavities on the seismic response of canyons

“…Figure 4 shows amplification patterns of semi-sine-shaped canyon for SV and P wave propagation in h/L = 0.7. Results are compared with results of Kamalian et al [28] in dimensionless period interval equal to 0.5 \ P2 \ 1.0 (short) and 2.0 \ P4 \ 4.17 (long). In this figure, the average amplification of each point on the canyon is calculated by the numerical integration of the spectral amplification with respect to the period.…”

“…Kamalian et al [28] studied seismic amplification effects of semi-sine-shaped canyons against the propagation of SV and P waves in time domain. In this paper, a dimensionless period interval of (P = k/2L = p.b/x.L) was considered, where k is incident shear wavelength, x presents the angular frequency of the wave, and L and b denote to the width of the canyon and shear wave velocity of medium, respectively.…”

“…Zhang and Zhao [68] and Zhao and Valliappan [69] used hybrid finite/infinite components technique to study effects of canyon-type topography on the seismic ground reaction against SH, SV and P waves. Furthermore, Kamalian et al [27,28] and Sohrabi-Bidar et al [60] solved wave propagation equations in time domain and examined the behavior of two-and three-dimensional canyon features using boundary element methods. Afterward, Wang et al [63] examined the characteristics of Rayleigh wave propagation in common topography models depending on finite difference method.…”