1. School of Resource & Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
2. School of Resources and Safety Engineering, Central South University, Changsha 410083, China
3. Department of Mining and Materials Engineering, McGill University, 3450 Rue University, Montreal, QC H3A 2A7, Canada
4. CERIS, Department of Civil Engineering, Architecture and Georesources, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal