Investigation of water ingress into uncracked and cracked cement-based materials using electrical capacitance volume tomography

[Display omitted] •Electrical capacitance volume tomography (ECVT) with the assembled square sensor can monitor the 3D moisture flow inside concrete and cracked mortar.•The response of ECVT to moisture is not affected by the coarse aggregates inside the concrete.•ECVT can locate crack and water sources in singled cracked mortar.•The ECVT reconstructions agreed well with the unsaturated water flow simulations. Moisture and other dissolved ions can easily enter cracked cement-based materials, leading to a series of degenerating processes. Electrical capacitance volume tomography (ECVT) is a powerful approach for detecting and visualizing the three-dimensional (3D) water distribution inside cement-based materials. In this paper, the water ingress in mortar and concrete was monitored and visualized in 3D by ECVT. The feasibility of ECVT was first verified by conducting a moisture transfer experiment inside uncracked mortars. Then, the water ingress process into cracked mortar and concrete was monitored and visualized using this technique, which further confirmed the ability to image 3D volumetric water content in materials with highly heterogeneous permittivity. In addition, the water distribution inside the cracked and uncracked mortars was simulated utilizing two finite element models. The simulated results agree well with the ECVT reconstructed results, supporting the applicability of ECVT to image 3D water transfer in uncracked and cracked cement-based materials.