Development of a Core Barrel for an In Situ Measurement of the Thaw Consolidation Behavior of Permafrost
Bibliographic record
Abstract
In permafrost areas, environmental changes, such as infrastructure, building, and climate change, have effects on the thermal regime of soil and can initiate permafrost degradation. As a result, this will lead to the degradation of the mechanical properties of the soil. Thus, good knowledge of permafrost characteristics is essential to make the right decisions during the design and construction phases of a project and to anticipate potential problems related to climate change. The goal of this project was to improve our capacity to characterize thaw-sensitive permafrost by developing a drilling tool that is able to carry out in situ tests. In partnership with the Mechanical Engineering Department of Laval University, an oedometric core barrel was designed, and a prototype was built. As the core barrel is modular, it is easy to clean and maintain. Once the barrel has penetrated frozen soils, thawing is initiated by an electric heating element. A pneumatic cylinder then allows the user to set a consolidation pressure, and drainage occurs radially along the first 20 cm of the core. The drained water is discharged at the top of the drill hole, and information on the thaw consolidation behavior is recorded during the test. The complete testing procedure can be made during the in situ drilling operation. In order to validate the testing procedure, laboratory tests were made in pure ice and synthetic permafrost reconstituted in barrels. The testing program has allowed improvement of the initial design of the equipment as well as the test procedure. The reliability of the thaw settlement/consolidation tests was evaluated for fine and coarse soils.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 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".