Time-dependent concentration of chlorides at the concrete surface revisited

ABSTRACT

Service-life modeling of concrete structures exposed to chlorides has received increasing attention in recent years. Despite developments in understanding the transport phenomenon, most models still have limitations, and their results should be interpreted cautiously. This paper presents a state-of-the-art review of recent advances in time-variant models of surface chloride concentration (C_s) used as a boundary condition in service-life models, examining the role that boundary conditions can play in service-life estimates. Moreover, an overview of the root causes of variability in experimental results and a critical review of the strengths and limitations of time-variant C_s is provided. The results of numerical studies show that the time-variant boundary conditions considered in this work performed reasonably well with short-term empirical data and matched well with field observations. However, this review highlights the need for long-term field data to validate the performance and reliability of results obtained from service-life models using time-variant boundary conditions.

KEYWORDS:

• Surface chloride
• service-life modeling
• concrete durability
• diffusion
• fickian models

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Notes on contributors

Mahmoud Shakouri

Mahmoud Shakouri is currently an assistant professor in the Department of Industrial Technology at University of Nebraska at Kearney. His research interests include service life modeling, biobased cementitious materials, corrosion, and concrete durability.