Vulnerability of Soil Slopes Against Seismic Damage Based on the Effect of Spatial Variability of Soil Properties on the Development of Permanent Seismic Displacements

Abstract

The most accurate estimation of seismic slope stability is one of the most important areas of geotechnical seismic engineering. The assumption that soil consists of layers with some average values ​​for soil parameters of each layer is not a realistic representation of actual conditions. The properties of a soil layer are not spatially invariant and the scale of changes can significantly affect the stability analysis of slopes. It is important to include in the analysis as many kinds of uncertainty, especially those resulting from the properties of soil mass and influencing the seismic stability of slopes.Stochastic methods have been introduced in order to calculate the uncertainty and spatial variability of soil parameters. Recent research took into account the spatial variation of parameters using the Random Field Theory. In theory, these variables exhibit autocorrelation, a trend in which the soil properties of a point appear to be correlated with the properties of neighbouring soil points (Vanmarcke, 1977). This study explores the influence of spatial variability of soil properties on the development of permanent displacements during seismic vibration of the slopes as well as the levels of seismic damage that can be caused. This effect is initially investigated for a fixed value of the maximum acceleration of the excitation, and then the results are expanded to include the effect of the seismic intensity level. The results show the curves of vulnerability of slopes against seismic damage and constitute a pretty useful tool for the design of slopes, taking performativity into account. 

Keywords

• Vulnerability,Slopes,Seismic Damage,Spatial variability,Permanent displacements

References

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