01663301

Component

Sulfate migration in cement stabilized subgrade along with its reaction with cement components is a very complicated distress process. It involves intricate interactions between porous media, moisture transport, and heat transfer. Existing studies have considered heat migration, while some others have focused on moisture content dependent modeling of this phenomenon. However, the community is in lack of a precise model that considers coupled interaction of temperature and humidity upon sulfate ingression. Therefore, it is of utmost importance to model the sulfate diffusion process considering coupled Thermo-Hydro-Chemical (THC) behavior of cement stabilized subgrades in order to improve the pavement design procedure and predict the performance. The intent of this research is to develop a comprehensive mathematical model of cementitious materials subjected to Sulfate Attack (SA). In this paper, a set of governing equations are developed, and a unique expression for sulfate diffusion coefficient is proposed. Finally, the equations are solved using finite element method, and the result accords well with the experimental results. The model has been proved to be adequate for evaluating sulfate propagation front in unsaturated cement stabilized pavements. The numerical model can also predict the amount of sulfate consumed during the reaction process.

This paper was sponsored by TRB committee AFP40 Standing Committee on Geo-Environmental Processes.

18-05529

English

17p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; References; Tables

Cement; Pavement distress; Porous materials; Stabilized materials; Subgrade (Pavements); Sulfates

Highways; Materials; Pavements

Transportation Research Board Annual Meeting 2018 Paper #18-05529

TRIS, TRB, ATRI

Jan 8 2018 11:24AM