Effect of carbon nanofibers on the pore fractal law of concrete

Abstract

In order to explore the effect of carbon nanofibers (CNFs) on the internal pore structure fractal law of concrete, carbon nanofiber reinforced concrete (CNFC) specimens with fiber content of 0%, 0.1%, 0.2%, 0.3% and 0.5% respectively are prepared, the internal pore structures of specimens in each group are analyzed by means of mercury intrusion porosimetry (MIP), and the pore fractal laws are further discussed by introducing fractal theory. The results show that, appropriate amount of CNFs can effectively reduce the total pore volume and the average pore size of concrete, and the inner pore size shows remarkable fractal characteristics, the fitting slope of ln(W n /r n 2) and lnQ n can be used as the fractal dimension D p of pore surface area; the D p decreased firstly then increased with the increase of CNFs content, and the larger D p is, the higher the large pore content and the larger the average pore size are.