Lambert, C, Ferrari, F, Thoeni, K & Giacomini, A 2016, 'Rockfall mitigation measures and design scenarios at the base of highwalls', in PM Dight (ed.), Proceedings of the First Asia Pacific Slope Stability in Mining Conference
, Australian Centre for Geomechanics, Perth, pp. 421-434, https://doi.org/10.36487/ACG_rep/1604_26_Lambert
This paper proposes to discuss the efficiency of typical rockfall mitigation measures implemented in open cut environments and aims at providing geotechnical engineers and mining engineers with some guidance for preliminary rockfall hazard assessment and management strategies. Firstly, a semi-quantitative approach is presented. An extensive sensitivity analysis of rockfall trajectories to highwall geometry was performed. Relationships were derived to estimate the expected rockfall energies and first impact location at the base of the highwall. An example of how these relationships can be used for the preliminary design of a protective berm is presented. Secondly, the efficiency of unsecured drapery systems is investigated using a three dimensional discrete element model. A wide range of rockfall scenarios were simulated to quantify the efficiency of draperies to reduce impact energies and constrain impact location close to the highwall. Implications for the design of underground entry portals and canopies are discussed where design requirements derived from the semi-quantitative approach are compared with examples of design scenarios currently used by practitioners.
Keywords: rockfall, hazard mitigation, draperies, underground entries
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