Mechanism of functional responses to loading of carbon fiber reinforced cement-based composites

Abstract

Single fiber pull-out testing was conducted to study the origin of the functional responses to loading of carbon fi ber reinforced cement-based composites. The variation of electrical resistance with the bonding force on the fiber-matrix interface was measured. Single fiber electromechanical testing was also conducted by measuring the electrical resistance under static tension. Comparison of the results shows that the resistance increasing during single fi ber pull-out is mainly due to the changes at the interface. The conduction mechanism of the composite can be explained by the tunneling model. The interfacial stress causes the deformation of interfacial structure and the interfacial debonding, which have infl uences on the tunneling effect and result in the change of resistance.

Creep behavior of graphene oxide reinforced cement composites: Experiments, numerical simulations, and prediction models

“…The specimen size was a prism of 40 mm × 40 mm × 160 mm. The mechanical properties of GO‐reinforced cement composites have been discussed in the literature 29 . Moreover, the effect of GO on the creep behavior of cement composites will be highlighted in our study, where four mortar specimens were considered for each water–cement ratio.…”

Research on Performance of Smart Concrete Materials and Self-Monitoring of Cracks in Beam Members

“…Because the smart concrete beam specimen is an irregular conductive matrix when cracking under load, there will be errors in the results when taking the resistance or resistivity as the standard. To facilitate the analysis, the resistance changes are normalized, so that resistance change rate (Fractional change in resistance, FCR) or resistance change percentage is used as a measureof resistance change [34][35][36]. At constant voltage, surface resistance change rate in tensile zone of smart concrete beam is calculated using the following formula: In the formula, FCR is resistance change rate (%).…”

Piezoresistivity and AC Impedance Spectroscopy of Cement-Based Sensors: Basic Concepts, Interpretation, and Perspective

“…The cause of piezoresistivity in cement-based materials is based on one or more of these factors: the slippage of the fibre–matrix interface [ 57 , 58 , 59 , 60 , 61 , 62 ], the change in the intrinsic resistance of the conductive admixtures [ 57 , 59 , 63 , 64 ], the change in the contact resistance between the functional additives [ 57 , 65 ], the change in the tunnelling distance between the conductive admixtures [ 57 ], and the change in the capacitance distance of the conductive fillers [ 57 , 66 ].…”