Numerical investigation of the energy absorption mechanisms of the selected ground support elements

Abstract

Abstract Ground support systems are critical in ensuring safety while maintaining excavation stability to support continuous production. In burst-prone mines, these systems must also withstand dynamic loading and large deformation. To achieve this, underground mines employ a combination of rock reinforcement and surface support elements to maintain the structural integrity of excavations. Designing an effective ground support system requires a comprehensive understanding of the mechanical behaviour of individual support components and their interactions under dynamic load. This paper investigates the mechanical behaviour of surface support elements, including welded wire mesh and fibre-reinforced shotcrete (FRS), as well as the reinforcement element commonly used in underground mining operations. The primary objective of this study is to develop 3D numerical models in explicit FEM that reasonably capture the main load–displacement trends and failure modes of ground support elements under controlled laboratory testing conditions. The developed models effectively captured load redistribution, load–displacement responses, and failure mechanisms observed in laboratory experiments. Once calibrated, these models were utilised to analyse the interactions between welded wire mesh and FRS. The combined system of welded wire mesh, plate, and Falcon Bolt was assessed under high-stiffness and low-stiffness boundary conditions . The energy absorption by the high-stiff system is 50% less than that of the low-stiff system. Conversely, in the low-stiffness system, reduced mesh restraint allowed more efficient load distribution, resulting in an energy absorption capacity approximately 10% higher than the theoretical value. The results revealed that localised stress concentrations at the bolt-mesh connection increased the risk of failure. These findings show the importance of selecting appropriate boundary conditions in numerical simulations to ensure a realistic representation of underground support behaviour. They also demonstrate the need to accurately identify potential failure mechanisms within support systems to improve overall design reliability. The calibrated numerical models serve as a reliable tool for evaluating the performance of support systems in underground mines, particularly under dynamic loading conditions. They can also be used in future studies to investigate the combined response of support elements within the system, contributing to the development of more effective ground control strategies in dynamic environments.