Complex mining exploitation : optimising mine design and reducing the impact on human environment (COMEX)

COMEX intends to improve the understanding of impacts of mining activity on structures and infrastructures. It started on 1st July 2012 and finished on 30th June 2015. The works realised in the WP1 concerns the analysis and the interpretation of in-situ observations to understand the origin of the disorders of underground mine (Poland) and open pit mine (Greece). A seismic damage scale was developed and validated for different European countries. Within WP2 the guidelines for the layout and support of longwall panels in subsidence damaged ground above previous workings were updated. This was based on detailed deformation monitoring and large and small-scale numerical modelling at a case study site where 5 longwalls over-worked previous longwalls of varying age and geometries. In addition, a numerical model was developed to improve prediction of surface subsidence over underground coal mines. The prediction of the subsidence consequences was studied using physical and numerical modelling. Two physical models were developed (1g and ng). Different technical approaches were used to simulate the masonry structure and to identify the damages. The results were validated using 3D numerical models. The results allowed identifying the damage level due to ground movement that transferred to a masonry structure. Different designs of underground mine and open pit mine were discussed in WP4. The main results concern the application of the mitigation recommendations to design the open pit mine and underground mine. For building, three mitigation techniques were tested using physical modelling and in-situ experimentation (periphery trench, geotextile and grout columns).