Calibration of the limit equilibrium pillar failure model using physical models

摘要

TTe limit equilibrium model, used in displacement discontinuity codes, is a popular method to simulate pillar failure. TTis paper investigates the use of physical modelling to calibrate this model. For the experiments, an artiffcial pillar material was prepared and cubes were poured using the standard 100 mm × 100 mm civil engineering concrete moulds. TTe friction angle between the cubes and the platens of the testing machine was varied by using soap and sandpaper. Different modes of failure were observed depending on the friction angle. Of interest is that signiffcant loadshedding was recorded for some specimens which visually remained mostly intact. TTis highlights the difffculty of classifying pillars as failed or intact in underground stopes where spalling is observed. TTe laboratory models enabled a more precise calibration of the limit equilibrium model compared to previous attempts. Guidelines to assist with calibration of the model are given in the paper. TTe limit equilibrium model appears to be a useful approximation of the pillar failure as it could simulate the stress-strain behaviour of the laboratory models.