Stress ratios in entire mine stopes with cohesionless backfill: A numerical study

Auteurs

Pengyu Yang, School of Architecture and Civil Engineering, Xi′an University of Science and Technology, 58 Yanta Rd, Xi′an, 710054, China, Research Institute on Mines and Environment, Department of Civil, Geological and Mining Engineering, École Polytechnique de Montréal, C.P. 6079, Succursale Centre-Ville, Montréal, H3C 3A7, QC, Canada
Li Li, Research Institute on Mines and Environment, Department of Civil, Geological and Mining Engineering, École Polytechnique de Montréal, C.P. 6079, Succursale Centre-Ville, Montréal, H3C 3A7, QC, Canada
Michel Aubertin, Research Institute on Mines and Environment, Department of Civil, Geological and Mining Engineering, École Polytechnique de Montréal, C.P. 6079, Succursale Centre-Ville, Montréal, H3C 3A7, QC, Canada

Type de document

Études primaires

Année de publication

2017

Langue

Anglais

Titre de la revue

Minerals

Résumé

Evaluation of stress states in backfilled mine stopes (or similar openings), using arching theory, can be largely impacted by the value selected for the earth pressure coefficient, K = σ′h/σ′v. Recently, the current study’s authors addressed the debate about the value of K near the opening center, based on Rankine’s active coefficient (Ka) and at-rest coefficient (K0). Here, stress ratios in vertical backfilled stopes are numerically assessed (in two dimension, 2D), considering both the independent and related backfill internal friction angle (ϕ′) and Poisson’s ratio (ν). Emphasis is placed on the backfill state near stope walls, where local rotation of stresses occurs, so the coefficient (K) and principal stress ratio, Kps (= σ′3/σ′1), should be distinguished. Parametric analyses indicate that values of K and Kps depend on the position and the relationship between ϕ′ and ν. Near the opening center, K (= Kps) is close to Ka when ν or ϕ′ is below a critical value; otherwise the value approaches K0, defined from ν. Near both walls, Kps is always close to Ka, while K is near K0 for related ν − ϕ′ cases and depends on their respective values for independent ν and ϕ′. Additional simulations conducted with interface elements indicate that the stress ratios near the opening center line are insensitive to interface roughness and are almost identical to values obtained without interfaces, but the stress ratios near walls may change for less rough or smooth interfaces. © 2017 by the authors. Licensee MDPI, Basel, Switzerland.

Mots-clés

Exploitation avec remblayage, Stowing and filling, Concentration de tensions, Stress concentration

Numéro de projet IRSST

2013-0029

Citation recommandée

Yang, P., Li, L. et Aubertin, M. (2017). Stress ratios in entire mine stopes with cohesionless backfill: A numerical study. Minerals, 7(10). https://doi.org/10.3390/min7100201