Numerical study of interactive ingress of calcium leaching, chloride transport and multi-ions coupling in concrete

In circumstances with wastewater and seawater, the behavior of multi-ions including calcium, chloride and others in concrete attracts attention. The present study investigated the multiple mechanisms that could happen under the special field situation above, including calcium leaching, chloride transport and multi-ion coupling. To realize the interactive ingress of multi ions, the simulation method for the processing of the individual mechanisms and the mutual influences is adopted. The distributions of the diversified ions are analyzed with the influence of the interfacial transition zone. The time-spatial distribution of porosity and its evolution mechanisms are investigated by considering the interaction with calcium ions in both pore solution and solid phase. The results indicate that calcium leaching would dominantly speed up chloride transport due to the coarsened pore structure, while the multi ions electrochemical coupling effect would facilitate calcium leaching in the early stage but subtly delay calcium leaching in the later stage.

Automated summary

This study investigates the behavior of multi-ions, including calcium and chloride, in concrete under wastewater and seawater conditions. Multiple mechanisms, such as calcium leaching, chloride transport, and multi-ion coupling, were analyzed. The interactive ingress of multi ions was realized through simulation methods, considering the individual mechanisms and mutual influences. The study also examined the distributions of diverse ions and the evolution mechanisms of porosity, considering the interaction with calcium ions in both pore solution and solid phase. The results suggest that calcium leaching accelerates chloride transport due to coarsened pore structure, and the electrochemical coupling effect of multi ions facilitates calcium leaching in the early stage but slightly delays it in the later stage.