The review of pore structure evaluation in cementitious materials by electrical methods

• The evaluation of pore structure by electrical methods is reviewed.
• Some equivalent circuit models of AC methods are discussed.
• Merits and demerits of ACIS and non-contact methods are commented.

This paper reviews the evaluation of pore structure in cementitious materials by means of electrical impedance methods from the view point of direct and alternative current tests with or without electrodes. Some main equivalent circuit models in the literatures, which are employed to evaluate the pore structure from experimental results of alternating current impedance spectroscopy (ACIS), are discussed. The latest utilization of non-contact resistivity/impedance measurement for the hydration monitoring, pore structure and transportation investigation is presented in this review. The related merits and demerits of ACIS with electrodes and non-contact methods and their application scenarios are also discussed.