282 Figure 5 – Strain preceding slope failure detected on fiber optic cable over 1-day period, Source: Ouellet et al, 2024 For strain measurements, Fibers are trenched, embedded, or attached to dam structures (e.g., embankments, spillways, foundations) to detect localized or widespread strain changes. The system detects anomalies like cracks, seepage, subsidence, or deformation caused by dam loading, settlement, seismic deformation and aging. Distributed strain monitoring is increasingly recognized in geotechnical research as an effective method for detecting subtle physical changes. This makes it an essential dataset for supporting TARP triggers in TSF applications. 3.4 DAS for far-field acoustic imaging and monitoring DAS complements DTS/DSS, often on the same fiber optics cable installed in the infrastructure, by providing dense measurements of strain-rate (i.e., deformation rate) along the fibre, enabling the TSF to be monitored as a spatially continuous seismic array. Two passive approaches are commonly cited for earthworks: (i) ambient noise interferometry (ANI), Figure 6, where cross‑correlation of ambient wavefields is used to estimate seismic velocities and their changes over time; and (ii) potentially detection of acoustic emissions associated with flowing water or evolving internal state. Applied programs in embankment dams show the application of extracting seismic velocities from DAS data. Comparing seismic velocities against a previous measurement or baseline can detect changes potentially associated with seepage/internal erosion. [2][3]. Figure 6- Monitoring Fiber deployed at Crest used for this study (left), Strong contrasts in dam velocity structure following ANI survey (Right). Source: Stork et al., 2022 DAS used as a periodic survey, can detect changes over time, in addition to fibre used to quantification of seepage rates [13][2]. 3.5 Data integration into TARPs and governance DFOS deployments at tailings scale will generate large spatiotemporal data volumes. Carefully designed data‑management strategies and automated workflows generate best results and are most likely to lead to actionable insights. DTS yields temperature‑versus‑distance data tracking temperature gradients and anomalies in the near‑field. DSS produces absolute strain measurements also within the
RkJQdWJsaXNoZXIy MTM0Mzk2