Quantification of soil non-linearity based on simulation.

Lussou, P; Bard, PY; Modaressi, H; Gariel, JC. SOIL DYNAMICS AND EARTHQUAKE ENGINEERING, 20: (5-8) 509-516.

Recent earthquake studies have demonstrated that non-linear behavior of soft soil can be significant compared to other effects affecting seismic motion. Therefore, the question is to know when sediment non-linearity is a first-order effect and when it is not. In this study, we propose a method for quantifying non-linear effects based on simulations. An elasto-plastic model is used to simulate the behavior of four materials (sands and clays). For each computation, the non-linearity is quantified by the use of a 'non-linear parameter' and compared to four non-linearity indicators. These computations suggest that the efficiency of an indicator depends on the nature of the soil underlying the recorder and that the most efficient indicator should be based on the high frequencies content rather than on the resonant frequency changes.