Cost optimization of cemented paste backfill: State-of-the-art review and future perspectives

A primary challenge in the mining industry is how to extract mineral and metal resources in a cost-effective and environmentally-friendly way. To help mitigate the environmental issues caused by mining operations, cemented paste backfill (CPB) is an effective method which has been widely adopted. This review first introduces recent achievements made in three main CPB design processes, but the priority is given to a comprehensive retrospective on how to reduce the operation investment from two academic perspectives: the contribution of additives and the arching effect. The inclusion of various additives in CPB preparation not only increasse the flowability but also improves the mechanical strength, which allows for less cement consumption. Furthermore, the arching effect in CPB can mitigate the vertical stress to 35% of its self-weight, and taking advantage of this effect in CPB design will reduce the amount of cement being used as well. To better introduce the arching effect, a review of the shear performance of the interface between CPB and the surrounding rock is also provided, focusing on laboratory tests and mathematical modeling. This review concludes with perspectives on the future and suggests further work that should be conducted to reduce the investment cost in the mining industry.