Calculation of chloride ion concentration in expressed pore solution of cement-based materials exposed to a chloride salt solution. (November 2016)

• Record Type: Journal Article
• Authors: He, Fuqiang; Shi, Caijun; Hu, Xiang; Wang, Ruipan; Shi, Zhenguo; Li, Qingling; Li, Pingliang; An, Xiaopeng
• Is Part Of: Cement and concrete research. Volume 89(2016)
• Page Start: 168
• Page End: 176
• Publication Date: 2016-11
• Subjects: Free chloride ion concentration -- Expressed pore solution -- Cement-based materials -- Electrical double layer -- Overlapping phenomenon of the diffuse layer; Cement -- Periodicals; Cement -- Research -- Periodicals; Concrete -- Periodicals; Concrete -- Research -- Periodicals; Ciment -- Périodiques; Béton -- Périodiques; Cement; Concrete; Periodicals; 620.135
• DOI: 10.1016/j.cemconres.2016.08.006
• Languages: English
• ISSNs: 0008-8846

Abstract

Abstract: To investigate the relationship between the chloride ion concentration of the expressed pore solution ( C e ) and the exposure solution ( C es ) of cement-based materials exposed to a chloride salt solution, a calculation of the C e, based on an electrical double layer (EDL) model was proposed. The C e values were calculated using the proposed equations, applying the measured parameters: relative potential ( δψ 0 ), dielectric constant ( ε ), porosity ( P ), bulk density ( D ), volume percentage ( p i ) of pores with diameter d i . The calculations explain why C e does not always equal to C es . The results indicate that the expression method does not test the concentration of free chloride ions in the bulk solution ( C Cl − b ) or the average concentration of the transportable chloride ions ( C ttr.a ) in the pores. However, the ratio ( C r ) of C e to C Cl − b and the relationship between C e and C ttr.a can be calculated to more accurately measure chloride ion migration in cement-based materials.