Chloride binding capacity of various hydrated cement paste systems

Effects of Electrochemical Chloride Extraction on Hydrated Products of Various Cement Paste Systems

“…On the other study, Tritthart (1992), who investigated the change of chloride ions in pore solution and total chloride content at different depths of cement paste plates under different storage condition, has shown that at the quantity of approximately 0.85-1.1% of total chloride content, which equal to 1.3-1.65 % NaCl, the chloride concentration in pore solution is about 0.226-0.240 mol/L. Tang et al (1993) and Delagrave et al (1997) indicated that, the bound and free chloride relationship is mainly depended on the total quantity of hydration products. Therefore, in this study the chloride concentration in solution 2, which is used to simulate the pore solution in cement paste that contain 1.5% NaCl, which associates to 0.91% Cl -, is assumed 0.227mol/L.…”

“…The concentration of chloride ions in pore solution is also studied widely while cement based materials are added or contaminated with different quantity of chloride ions (Bertolini et al 2004;Burchler et al 1996;Larbi et al 1990;Tritthart 1989aTritthart , 1989bTritthart , 1992Tritthart , 2009Tritthart et al 2003). Nowadays, the relationship between free chloride and bound chloride can generally be represented by the Fleundlich isotherm equation at high free chloride concentrations and the Langmuir isotherm equation at low free chloride concentration (Tang et al 1993;Delagrave et al 1997); and the effects of other criteria are described by adsorption constants which varied widely. According to the research of Delagrave et al (1997) in which the authors studied the chloride binding capacity of various types of cement paste with the water-to-binder ratio of 0.25 to 0.45, the free chloride concentration varies about 0.2-0.3 mol/L since the bound chloride content is in the range of 0.25-0.5%, which is approximate to the binding chloride in this research.…”

“…Nowadays, the relationship between free chloride and bound chloride can generally be represented by the Fleundlich isotherm equation at high free chloride concentrations and the Langmuir isotherm equation at low free chloride concentration (Tang et al 1993;Delagrave et al 1997); and the effects of other criteria are described by adsorption constants which varied widely. According to the research of Delagrave et al (1997) in which the authors studied the chloride binding capacity of various types of cement paste with the water-to-binder ratio of 0.25 to 0.45, the free chloride concentration varies about 0.2-0.3 mol/L since the bound chloride content is in the range of 0.25-0.5%, which is approximate to the binding chloride in this research. On the other study, Tritthart (1992), who investigated the change of chloride ions in pore solution and total chloride content at different depths of cement paste plates under different storage condition, has shown that at the quantity of approximately 0.85-1.1% of total chloride content, which equal to 1.3-1.65 % NaCl, the chloride concentration in pore solution is about 0.226-0.240 mol/L.…”

Durability of materials based on a polymer-silicate matrix and a lightweight aggregate exposed to aggressive influences combined with high temperatures

“…XRD did not identify Friedel's salt in any of the tested specimens. The crucial factor of the formation of this chemical compound is the temperature, which is, inter alia, mentioned by Delagrave et al 3 , Izquierdo et al 4 , Yuan 5 and Tang 6 . It is then evident that the damage of the structure caused by the combination of frost and the solution with chloride ions is purely mechanical.…”

“…However, the reaction of the mentioned components is considerably influenced by several factors. As A. Delagrave et al 3 and D. Izquierdo et al 4 , Q. Yuan 5 and L. Tang 6 state, concentration of chloride ions, type of cement, replacement of cement, temperature or water-cement ratio are important. According to F. P. Glasser et al 7 , a penetration of chloride ions with the consequent formation of Friedel's salt can, inter alia, cause a gradual filling of the porous structure of a given composite, which eventually slows down the transportation of Clions.…”