Nestor Bellido, Zenón Aguilar

Abstract:

The seismic response of tailings dams is highly dependent on the intensity measures (IMs) of the input ground motions. For this reason, several researchers have used seismic fragility functions to evaluate the seismic performance of geotechnical structures. Seismic stability analyses of tailings dams are further challenged by the uncertainty and variability of IMs for a given earthquake scenario and site conditions. This study presents the seismic performance of a tailings dam affected by subduction earthquakes by generating fragility functions and analysing the effectiveness of different IMs in predicting a damage measure (DM), such as horizontal displacements. Our analyses are based on finite-difference numerical simulations using advanced constitutive models. The selected ground motions are compatible with the Maximum Credible Earthquake (MCE), which is common in the practice in South America. The results show that the Arias intensity is the most efficient and optimal IM in predicting the horizontal crest displacements of the dam. Furthermore, the analytical fragility functions based on numerical results using peak ground acceleration (PGA), Arias intensity (AI), cumulative absolute velocity (CAV), and peak ground velocity (PGV) are presented. The fragility functions can be a useful tool to assess the probability of damage levels for designed tailings dams based on their design earthquake and acceptable risk. In addition, the obtained fragility functions could be used to define alert levels to be considered in the operation manual of the tailings storage facility (TSF).

Keywords: Fragility functions, tailings dam, subduction earthquakes, dynamic analyses, efficiency.

Date Published: May 31, 2024
DOI: 10.11159/ijci.2024.002

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