Non-destructive monitoring of fiber orientation using AC-IS: An industrial-scale application

A comprehensive study has been undertaken to investigate the ability of AC-impedance spectroscopy (AC-IS) to non-destructively monitor the fiber dispersion of conductive fiber-reinforced cement-based materials. Previous work showed that AC-IS effectively monitors various fiber dispersion issues in lab-scale steel fiber-reinforced specimens. In this part of the study, AC-IS was used to study fiber orientation in an industrial-scale pre-cast concrete beam. A conventional method-image analysis (IA)-was used to verify the results of AC-IS measurements. The results of AC-IS and IA were found to match very well in experimental uncertainty. Splitting tensile tests and bending tests were conducted on the parts of the beam to study the effects of fiber orientation on the mechanical performance. The results of the mechanical tests also confirmed the results of AC-IS with splitting tensile strengths increasing as the alignment of fibers increased.