Study on the hydro-geotechnical properties and establishment of a numerical model for waste rocks

Mines produce large amount of waste rocks, mostly disposed on ground surface in form of pile. In underground mines, waste rocks are increasingly used to construct barricades to retain mining backfill in the stopes. Waste rocks can also be used as inclusions to accelerate the drainage and consolidation of tailings. To properly evaluate the stability of these infrastructures, numerical models are needed. However, the existing numerical models suffer from two major limitations. First, it is difficult to determine the mechanical properties of full-scale waste rocks, due to the excessively large size of the particles. Second, the most commonly used Mohr-Coulomb model fails to describe the nonlinear behavior of waste rocks. To overcome the two limitations, the objectives of this project are (i) identifying or proposing a method to correctly predict the hydro-geotechnical properties of the full-scale waste rocks and (ii) establishing a numerical model to describe the hydro-geomechanical response of the waste rocks. A more efficient failure criterion, called MSDPu criterion, will be introduced and built in FLAC 3D for stability analysis. It is expected that the infrastructure design based on the results ensuing from the realization of the project will be more economic and more reliable.

Faculty Supervisor:

Li Li

Student:

FEITAO ZENG

Partner:

Mine Canadian Malartic

Discipline:

Engineering - civil

Sector:

Mining and quarrying

University:

École Polytechnique de Montréal