Dynamic performance of cemented rockfill under blast-induced vibrations
Notice bibliographique
Résumé
In this thesis, a new methodology for the design of CRF under static and dynamic loading conditions is developed. First a comprehensive literature review of the backfill material is accomplished which included a review of CRF operations and laboratory testing programs. This is followed by a review of numerical modelling studies performed on CRF. Based on the findings from literature review, two numerical models for CRF are developed using FLAC3D code. One of the models considers stopes to be inclined at about 67 degrees and the other considers vertical stopes. The numerical models are then used to study different aspects of CRF practice including the loading conditions, blast-induced vibrations from adjacent production stopes, vertical block mining method, CRF properties, CRF placement method and segregation. A case study mine CRF model is then constructed in accordance with site conditions and the geomechanical data provided by the mine. The case study mine numerical model is calibrated with in-situ stress measurements previously conducted at the case study mine. Mining and backfilling sequence is simulated with the calibrated model and the secondary stope is mined out in three lifts. In-situ blast vibration monitoring experiment in CRF is performed at the case study mine. Two geophones are installed: one inside CRF and the other on the surface of the CRF, and all three production blasts of the adjacent secondary stope are recorded. The detailed procedure, installation and results are presented in the thesis. The results are also used for numerical model calibration. To calculate damping coefficient for the model and blast load magnitude an equivalent cavity model is constructed. The equivalent cavity model is applied with reduced borehole pressure and the model is compared with charge-weight scaling law. The blast load and damping coefficients are extracted from equivalent cavity model and applied as input parameters for the CRF model. The numerical model is calibrated using blast load and damping coefficients obtained from the equivalent cavity model by computing the blast vibrations at a location similar to the one on site. The model is calibrated for all three blast lifts and results are presented. Finally, a CRF failure control study is carried out which encompasses the base case scenario of a planned stope at the case study mine, selective mining strategy for mining high grade ore, strategy of leaving an ore skin, tactically varying CRF properties vertically in CRF. In addition a parametric study is conducted to improve CRF stability by varying CRF properties and possible trends are presented. All results compare static loading versus blast loading scenario on CRF. The results include comparison of backfill stresses and profiles of peak particle velocity. Results of all analyses are presented along with the findings, conclusions, suggestions for future work and statement of contribution.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».