Koupouli, NJF, Belem, T & Rivard, P 2017, 'Shear strength between cemented paste backfill and natural rock surface replicas', in M Hudyma & Y Potvin (eds), UMT 2017: Proceedings of the First International Conference on Underground Mining Technology, Australian Centre for Geomechanics, Perth, pp. 375-385, https://doi.org/10.36487/ACG_rep/1710_29_Koupouli
(https://papers.acg.uwa.edu.au/p/1710_29_Koupouli/)
Abstract: After placement underground, the physical–chemical and mechanical properties of cemented paste backfill (CPB) will evolve over time due to self-weight consolidation and binder hydration. This paper deals with an experimental investigation into the shear strength behaviour of the CPB–rock interfaces using a direct shear machine. Numerous shear tests were conducted. The rock interfaces were made from two natural rock surfaces (schist and granite) in SikaGrout mortar replicas. Both frictional shear and shear bond strengths were determined. The results show that the shear strength at the schist interface (rougher) is higher than the one at the granite interface. The shear bond strength or cohesion and the interfacial angle of friction depend on the CPB curing time and the applied normal stress.

Keywords: cemented paste backfill, natural rock surface, shear strength, cohesion, angle of friction