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.

Benched slopes are commonly used in engineering practice to provide stable and safe access to mining sites, transportation routes, and construction sites. Therefore, their stability under seismic loading is crucial and needs to be considered to improve empirical design. This study investigated single and double-benched slope models constructed with the same lateral confinement area but different shapes. They were tested using a centrifugal shaking table inducing different ground motion intensities. The results indicated that shallow sliding, triggered by the ground motion, started from the crest of the slope and gradually developed towards the lower benches. The stability of slopes with the same cross-sectional area of benches changed based on the bench configuration. Furthermore, the rupture surface of the slope was not exactly a plane surface, but rather a three-dimensional curved surface, indicating that weight, moment and lateral confinement played a crucial role in the seismic deformation behavior of the benched slope. The findings of this study highlight the need for a more accurate and reliable design concept that can optimize the slope geometry and reinforcement techniques to enhance the dynamic stability of benched slopes in various engineering applications.

Nonlinear seismic analysis of embankment dams is crucial, especially in regions with high seismicity. The lack of rigorous seismic evaluations of these massive structures can lead to catastrophic failures. The earthquake-induced failure of embankment dams is often evaluated by the magnitude of seismic deformations resulting at the crest and other critical locations. Horizontal seismic and vertical gravitational forces are the primary loads considered in general for evaluating the seismic response of embankments during an earthquake event, ignoring the hydrodynamic forces acting on the upstream face. But in cases where the permeability of the upstream portion of the dam is low, accumulation of hydrodynamic forces on the upstream face of the embankment dam may play a significant role in the dynamic response. Besides, it also leads to the generation of excess pore pressure inside the dam body. Consequently, the role of hydrodynamic forces is critical in understanding the seismic response of embankment dams. The study attempts to study the role of hydrodynamic forces on the dynamic response and stability of the embankment dam founded on different foundations. Seismic soil-structure interactions of an embankment dam would also be included using a finite element two-dimensional plain strain model. The effect of interaction between the dam body and the bedrock is contemplated by using soft, medium, and hard bedrock foundation strata. Additionally, the influence of dam geometry on the seismic response of the dam and its Soil Structure Interaction (SSI) is also examined. Results reveal that ignoring the hydrodynamic effects significantly underestimates the stresses induced in the dam body at different foundation types. Therefore, a comprehensive study of the hydrodynamic effects on the dam body is fundamental in defining the behaviour of embankment dams under seismic activity.

Spatial variability of soil properties is considered as a major source of uncertainties in geotechnical engineering. Effects of spatial variability of soil properties on slope stability have received considerable research attention in the literatures. However, it is worth noting that the consequence of a landslide is often determined by the transportation and final deposition of the sliding soil mass, which is also significantly affected by the spatial variability of soil. At the same time, seismic excitation or earthquake can trigger large landslides. Few literatures studied the effects of seismic motion on the post-failure behavior of slope considering the spatial variability of soil properties. In this paper, the effects of seismic motion on the runout characteristics of post-failure slope had been studied using random material point method (RMPM). First, the deterministic analysis was investigated, revealing that the seismic action increases the runout characteristics of the post-failure slope, the runout distance, the volume of the sliding mass, and the influence distance. Secondly, the spatial variability was considered, and 1500 random field realizations were simulated. It was found that the spatial variability had a promoting effect of seismic motion on the runout characteristics of the post-failure slope.

The fragility curve, which specifies the likelihood that a structure would sustain damage that exceeds a certain threshold for different levels of loading intensity, is a newly developed method for the seismic risk assessment of all at-risk projects. Median and log-standard distribution are the two parameters constituting the cumulative lognormal distribution function, typically used to describe fragility curves. An investigation of the response of a road embankment geotechnical structure exposed to liquefaction-induced deformation driven by earthquakes is presented in the current work. The elasto-plastic and effective stress-based UBC3D-PLM model is used in the numerical analyses based on 2D FE analysis. A rigorous calibration process is carried out to generate the model parameters concerning laboratory test findings from past literature. With increasing intensity of ground motion (PGA), permanent embankment settlement (PES) is used to indicate the extent of the damage. A collection of 9 separate ground motions, scaled to different intensity levels, were used in the incremental dynamic analysis (IDA) that has been used to perform the fragility analyses. It has been observed that the embankment experiences more settlement even with low to moderate ground motion intensity due to the existence of the liquefiable foundation layer. To assess the vulnerability of an earthen embankment exposed to liquefiable foundation soil, different factors have been taken into account, including the relative density of the liquefiable underlying soil, the thickness of the liquefiable layer, and the geometry of the embankment (height and width). It has been noticed that liquefiable layer properties are the primary and embankment properties are the secondary parameters influencing the vulnerability of embankment supported on liquefiable soil deposit.

Shake table tests on levees deteriorated by seepage-induced internal erosion are performed in a geotechnical centrifuge to investigate the effects of erosion-induced heterogeneity and stiffness/strength reduction on the seismic response of the levees. In the experiments, a model embankment made of gap-graded soil is first subjected to repeated seepage flow by changing the water level in the flood channel. After lowering the water level, earthquake motions are applied to the model deteriorated by seepage-induced internal erosion, subsequently. The test results reveal that the natural frequency and equivalent shear wave velocity of the embankment significantly decrease with the seepage-induced internal erosion, suggesting that reduction of the soil stiffness occurs due to the internal erosion.

The authors are studying the possibility of early warning of rock mass collapse and monitoring of the precursor phenomena of rock mass slope failures in order to further improve road management and road safety. A remote automatic monitoring system using a high-precision 3D MEMS accelerometer was installed on a road slope of unstable bedrock in Hiroshima Prefecture, Japan, and a verification test is carried out to understand the effectiveness of the system and issues to be addressed and improved. The earthquake occurred at 1:08 a.m. on January 22, 2022 in the Kyushu region of Japan was measured, and a good result was received base on this test. The result of details of the evaluation of unstable rock slopes are reported in this paper. This experimental technology can be used for road maintenance management to determine the appropriate timing of countermeasure works and for safety management during construction. In the future, a more appropriate method of evaluating rock instability will be investigated without waiting for an earthquake to occur by measuring and analyzing vibration sources such as vehicle vibration.