Electrical charges and energies of cement and pozzolan particle surfaces

Abstract

The aim of this study was to identify interaction mechanisms among particles in the hydration of pozzolan cements. To this end, chemical, physical, mineralogical and electrokinetic analyses of samples were conducted. Furthermore, free surface energy components were defined by Van Oss, Chaudry and Good equations and the contact angle values of samples were determined by using the thin layer wicking method. The results show that the addition of water turns solid–air interfaces into solid–liquid interfaces (wetting), while attraction and repulsion take place depending on the electrical charges on particle surfaces. While total surface energy and components of particles seek to attain balance as a result of wetting, hydration and pozzolanic reactions occur.