Saeidi, N, Millar, D, Fava, L & Cai, M 2014, 'Towards mining schedule optimisation constrained by geomechanics', in M Hudyma & Y Potvin (eds), Deep Mining 2014: Proceedings of the Seventh International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 485-498, https://doi.org/10.36487/ACG_rep/1410_33_Saeidi (https://papers.acg.uwa.edu.au/p/1410_33_Saeidi/) Abstract: This paper reports work-in-progress that has the aim of incorporating geotechnical constraints on the optimisation of schedules of underground mine excavation activities. Optimal mine schedules are those for which the net present value (NPV) is maximised under a given financial model. The approach aims to consider the visco-elastic behaviour of rock when analysing the stability of excavations for constraint formulation. Changes in deviatoric stress around multiple, sequential openings or excavations are mapped and are shown to be influenced by both changes in the time between excavation events and the sequence of excavating events. The results of this analysis are presented in this paper. The approach is predicated on a causality principle for mine seismicity which requires a time dependent response (visco-elastic or possibly visco-elasto-plastic) of the rock mass. This is potentially difficult to conceive for rock masses at great depth, but is nevertheless evidenced by mine seismicity records from deep level mining operations, some of which are reviewed in this paper. The output of these geotechnical sequencing studies will ultimately be cast as constraints on a mine schedule optimisation process.