Erismann, F, Hansson, M & Krutrök, B 2022, 'Concrete: an enabler of large-scale block and sublevel cave mining projects globally', in Y Potvin (ed.), Caving 2022: Proceedings of the Fifth International  Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 151-164, https://doi.org/10.36487/ACG_repo/2205_08
(https://papers.acg.uwa.edu.au/p/2205_08_Erismann/)
Abstract: Concrete, applied by a range of different methods and forms has been used in large-scale block and sublevel cave operations for decades. However, over the last 20 years, concrete has seen an exponential growth in usage for a wide variety of applications. Thanks to its local availability, its good cost performance compared to other construction and underground support technologies, and the flexibility of production, transport and application, concrete has become the go to material when it comes to efficient design and execution of critical key components of mass-mine structures. This paper gives an overview about such critical infrastructure components such as shafts, raises, ore and waste passes and yielding shotcrete liners for primary and permanent underground support.
As the design, production, transport and placement of the concrete are the most important factors for the successful completion of a specific project, various concrete systems used today in different underground mines are discussed. Such systems include the batching of large concrete volumes in wet batch plants above or underground, the supply of pre-bagged concrete to the point of use, the operation of concrete slick lines to deliver concrete underground and the application of sprayed concrete in various forms for a range of applications.
Examples and lessons learned from large caving projects such as Kiruna in Sweden, Grasberg in Indonesia, Oyu Tolgoi in Mongolia and Chuquicamata in Chile have been compiled and critically reviewed. With view towards the expected service life, the durability of concrete is discussed. The paper also discusses the sustainability aspect when using concrete as a construction material and the potential impact of new, concrete related technologies on the lifecycle assessment of such materials. Such technologies include clinker free cements and technologies to reduce the overall amount of cement and steel in concrete.

Keywords: shotcrete, concrete, block caving, underground support, sustainability, sprayed concrete, ore passes, admixtures, fibres