The Electrical Resistivity of Concrete with Emphasis on the Use of Electrical Resistance for Measuring Moisture Content

Abstract

Abstract The paper describes an investigation of the electrical resistivity of concrete. In particular, electrical resistance of concrete was found to increase with decreasing water-cement ratio and increasing aggregate-cement ratio and entrained air content. The results show that calculating a water-concrete ratio by volume provides a convenient way of comparing the electrical resistivity of concretes of different mix proportions. The study also demonstrates that electrical resistance can be used to measure the moisture content of concrete. Electrical resistance increases as moisture content decreases with the least rate of change within the highest range of moisture contents. Although other techniques for measuring moisture content of concrete are more accurate, the use of electrical resistance has the advantage of being a relatively simple procedure that uses inexpensive equipment.