The use of the Barcelona test as quality control of fiber reinforced shotcrete for underground mining

The application of fiber reinforced shotcrete as primary system support in underground mining applications faces major quality control problems due to the complex setup and sophisticated equipment necessary to obtain the mechanical parameters from bending tests. Considering the advantages presented by the double punch test (also known as Barcelona), the present work investigated the influence of the machine stiffness and system control methodology (using the actuator LVDT and circumferential extensometer under closed loop) on the post-peak behavior of FRC of the Barcelona test and its correlation with three-point bending tests. While machines with higher stiffness significantly reduced the post-crack instabilities and mitigated the correlation errors, the circumferential extensometer control successfully limited the machine influence on the post-crack properties of FRC. (C) 2020 Elsevier Ltd. All rights reserved.