Earthquake-Soil Interaction

Book excerpt: Comprises a selection of articles on interactions between earthquakes and the soil in which they propagate. The book is concerned with soil composition and geomechanical features, which affect earthquake propagation and intensity; it also addresses detrimental effects of seismic shaking on soil properties and stability. Modelling is applied to investigate the effects of cracks and various types of soil damping on seismic waves. Elastic, poroelastic, elasto-plastic, constitutive models are adopted in conjunction with rigorous mathematical techniques or approximate methods such as boundary elements or finite differences. A substantial part of this volume is dedicated to soil liquefaction, an important consequent of seismic shaking that results in substantial loss of soil strength and stiffness. Criteria are proposed for assessing the liquefaction potential of a site. Data collected from soil samples, either in the laboratory or in-situ, are analysed to provide values for the critical parameters on which liquefaction depends. The occurrence of landslides is addressed by assessing slope stability through a systematic geophysical and geotechnical characterisation of the soil mass followed by finite element modelling. The bearing capacity of the soil is directly obtained by laboratory testing of soil samples, as well as from reliable empirical relations generated by combining such test data with in-situ measurements of soil dynamic properties.