Resumen de A simple approach to site‐response modeling: the overlay concept
James Kaklamanos, Luis Dorfmann, Laurie G. Baise
Site-response analyses are used to estimate the ground motion at the surface, as a function of the properties of the soil profile and the bedrock ground motion at the base of the soil profile. The most frequently employed site-response model in engineering practice is the equivalent-linear site-response model, a frequency-domain program that is coded in the computer program SHAKE (Schnabel et al., 1972; Idriss and Sun, 1992; Ordóñez, 2010). Using a large database of ground motions in the Kiban-Kyoshin network (KiK-net) of downhole arrays in Japan, Kaklamanos et al. (2013, 2015) found the equivalent-linear site-response model becomes inaccurate at shear strains of approximately 0.1%-0.4%. At larger strains, to model fully nonlinear behavior, site-response calculations should be performed in the time domain, which allows for a more accurate representation of the true cyclic stress-strain path. Finite-element methods are a powerful technique for modeling nonlinear site response, allowing for the representation of advanced constitutive behavior, 3D wave propagation, soil¿structure interaction, and complex geometry.
The purpose of this paper is to present a simple methodology for modeling earthquake site response in any finite-element program, using an overlay model to represent nonlinear soil behavior. This paper presents a literature review of the overlay approach, the advantages of the overlay approach, practical details on its implementation in any finite-element program, how this approach may be easily extended to capture more complex behavior, and an analysis of example results using recent KiK-net data. There has been much focus in the literature on improving soil models to advance our ability to predict site response (e.g., Hartzell et al., 2004; Kwok et al., 2007; Phillips and Hashash, 2009). Numerous nonlinear site-response programs have been...
