Effects of Conductive Phase on Properties of Concrete

Abstract

In this paper, the effects of graphite and carbon fiber on the properties of concrete were studied, the 28d compressive strength and electrical resistivity of concrete were measured, and the microstructure of concrete was observed. The results show that the graphite could improve the conductivity of concrete meanwhile reduce the compressive strength, and that the carbon fiber can improve the compressive strength of concrete, but its influence is considerably limited. Only when the mixing amount of graphite is higher than 1%, the compressive strength of concrete will increase along with the increase of mixing amount of carbon fiber, and the lamellar structure of graphite will be obvious, and the lamellar connection between graphite flakes will be in good condition. When the mixing amount of carbon fiber is 0.8%, dense connection will be formed between the carbon fiber & graphite and the hydration products. The combined mixture of graphite and carbon fiber can form a dense and relatively complete conductive network and is beneficial to the improvement of compressive strength of concrete.