An improved methodology for applying the influence function for subsidence hazard prediction
Résumé
The extraction of ore and minerals by underground mining often presents important risk for surface infrastructures. Several methods that have been developed to predict ground subsidence, and the influence function method (IFM) is one of the most efficient for predicting this phenomenon in the context of mining engineering. However, applying this method to a specific mining site requires adjustments that are difficult to achieve. In this paper, a methodology is proposed for adjusting the IFMs to each mining site. It is shown that the maximum subsidence depends on both the Width(W)/Height(H) and Length(L)/W ratios of mine panel. Moreover, the effect of the length variation becomes negligible for L/W ratio values greater than 4, but it is significant for values around 1. The influence angle of each mine panel has a significant effect on the subsidence, and a variation of 5 degrees may lead to significant variations in the prediction. A coefficient of dimensions reduction (CDR) used for adjusting the IFM results in each mine panels is used to adjust the value of subsidence above the border of the mine panels. The appropriate influence angle and CDR parameters should be calculated for each mining region.