Evaluation of liquefaction potential of mine tailings using elastic wave velocity
Bibliographic record
Abstract
The extensive damages resulting from static liquefaction re-emphasized the need for reliable criteria in predicting the possible development of this phenomenon. This research presents and evaluates elastic wave velocities in determining the boundary between contractive or dilative tailing materials in the laboratory. The effects of factors such as strain rate, confining pressure and fine contents on liquefaction potential of tailings are also discussed. To achieve the above objectives, an experimental investigation of the behavior of undrained tailings at confining pressures ranging from 25 to 280 kPa and under two strain rates of 0.5 and 1 mm/min was carried out using a modified Wykeham Farrance triaxial apparatus. As part of this research, a bender element system consisting of piezo-ceramic transducers placed in the loading head and base pedestal of the triaxial cell, a control box and software to generate and receive signals were developed. The system was employed to measure shear and compressive wave velocities (Vs and Vp) during both consolidation and ultimate steady state. These elastic wave velocity measurements were used to develop relationships between void ratio (e), mean effective normal stress (P') and elastic wave velocities. After consolidation, the specimens were loaded in shear under constant strain rates to determine their ultimate steady state at large strains. The analysis of the results obtained from this research shows limited strain softening response (limited liquefaction) in fine and medium-grained tailings whereas coarse-grained tailings illustrate a strain hardening response or dilative behavior. Shear wave velocities measured during the consolidation stage show better correlation with the ones obtained from the relationships, particularly in fine and medium-grained tailings. This is due to the fact that pore water may affect compressive wave velocity measurements and cause errors in the P wave measurements. An increase in strain rate in fine-grained tailing does not increase contractiveness, but rather does exactly the opposite. In other words, higher strain rates are associated with higher stability for fine-grained tailings. This is in contrast with the effect of high strain rates on coarse and medium-grained tailings. The membrane effect as well as vibration induced by high strain rates and low volume compressibility in coarse-grained tailings may explain the lower liquefaction resistance in medium and coarse-grained tailings under high strain rates. It should be noted that the instability region becomes larger as confining pressures increase showing more liquefaction potential under higher confining pressures.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".