Seismic response of a tailings sand dam

Abstract

This article investigates the seismic performance of the El Torito tailings dam, located in central Chile, during the 2015 Illapel Earthquake. Two-dimensional plane strain time domain finite element (FE) analyses were performed to simulate the construction, operation, and seismic response of the tailings storage facility (TSF). The hydro-mechanical (HM) coupled consolidation formulation implemented in the Imperial College Finite Element Program (ICFEP) is employed in the simulations. Firstly, a state parameter-based bounding surface plasticity model (BSPM) is calibrated against the laboratory and field data of the tailings materials, highlighting the challenges of the process. Then, the construction and operation of the El Torito tailings dam is simulated, following the detailed construction sequence of the TSF prior to the application of any seismic loading. Finally, the seismic response of the 2015 Illapel Earthquake is examined, where the results are compared with the recorded data at the crest and toe of the dam. The computed results suggest satisfactory agreement with the monitoring data, predicting similar acceleration response spectra for a wide range of periods.