Dynamic characteristics of a tailings dam embankment using a dense seismic array:Preliminary results
Abstract
The dynamic characteristics of a tailings dam embankment are relevant for estimating the dynamic performance of the tailings deposit during large earthquakes. This paper reports the deployment of a dense seismic array installed over the 80m height cycloned-sand embankment dam of a tailings deposit located in Central Chile. The network consisted of 28 short-period seismic stations with triaxial 4.5Hz geophones that continuously recorded ambient seismic noise and earthquakes during four weeks. The seismic stations were deployed along the embankment crest, the downstream slope, and the foundation soil. Single-station records were processed using the H/V spectral ratio method to estimate the embankment dam predominant vibration frequency using both ambient seismic noise and earthquake records. The results from the H/V spectral ratios from both types of signals are consistent and show that the foundation soil is stiffer than the embankment dam, that the predominant vibration frequency of the embankment is about 1 Hz, and there are differences in the vibration frequency along a cross section of the downstream slope. Finally, the results of the H/V spectral ratios are compared with standard spectral ratios calculated between the crest and the foundation of the embankment wall using the available earthquake records. Both methods are consistent in terms of the predominant vibration frequency and amplification factors.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMPA41E1155C
- Keywords:
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- 1020 Composition of the continental crust;
- GEOCHEMISTRY;
- 9305 Africa;
- GEOGRAPHIC LOCATION;
- 9360 South America;
- GEOGRAPHIC LOCATION;
- 8103 Continental cratons;
- TECTONOPHYSICS