Prediction of Concrete Hydration Behaviour and Cracking Tendency Based on Electrical Resistivity Measurement, Cracking Test and ANSYS Simulation
Hydration process, crack potential and setting time of concrete grade C30, C40 and C50 were separately
monitored using non-contact electrical resistivity apparatus, a novel plastic ring mould and penetration resistance method
respectively. The results show highest resistivity of C30 at the beginning until reaching the acceleration point when C50
accelerated and overtaken the others, and this period corresponds to its final setting time range, from resistivity derivative
curve, hydration process can be divided into dissolution, induction, acceleration and deceleration periods, restrained
shrinkage crack and setting time tests demonstrated the earliest cracking and setting time of C50, therefore, this method
conveniently and rapidly determines the concrete’s crack potential. The highest inflection time (ti), the final setting time (tf)
were obtained and used with crack time in coming up with mathematical models for the prediction of concrete’s cracking
age for the range being considered. Finally, ANSYS numerical simulations supports the experimental findings in terms of
the earliest crack age of C50 and the crack location that, highest stress concentration is always beneath the artificially
introduced expansion joint of C50.
Index terms: Concrete hydration, Electrical resistivity, Restrained shrinkage crack, Setting time, Simulation.