TY - JOUR

T1 - Development of a multi-species mass transport model for concrete with account to thermodynamic phase equilibriums

A1 - Hosokawa,Yoshifumi

A1 - Yamada,Kazuo

A1 - Johannesson,Björn

A1 - Nilsson,Lars-Olof

AU - Hosokawa,Yoshifumi

AU - Yamada,Kazuo

AU - Johannesson,Björn

AU - Nilsson,Lars-Olof

PB - Springer Netherlands

PY - 2011

Y1 - 2011

N2 - In this study, a coupled multi-species transport and chemical equilibrium model has been established. The model is capable of predicting time dependent variation of pore solution and solid-phase composition in concrete. Multi-species transport approaches, based on the Poisson–Nernst–Planck (PNP) theory alone, not involving chemical processes, have no real practical interest since the chemical action is very dominant for cement based materials. Coupled mass transport and chemical equilibrium models can be used to calculate the variation in pore solution and solid-phase composition when using different types of cements. For example, the physicochemical evaluation of steel corrosion initiation can be studied by calculating the molar ratio of chloride ion to hydroxide ion in the pore solution. The model can, further, for example, calculate changes of solid-phase composition caused by the penetration of seawater into the concrete cover. The mass transport part of the model is solved using a non-linear finite element approach adopting a modified Newton–Raphson technique for minimizing the residual error at each time step of the calculation. The chemical equilibrium part of the problem is solved by using the PHREEQC program. The coupling between the transport part and chemical part of the problem is tackled by using a sequential operator splitting technique and the calculation results are verified by comparing the elemental spacial distribution in concrete measured by the electron probe microanalysis (EPMA).

AB - In this study, a coupled multi-species transport and chemical equilibrium model has been established. The model is capable of predicting time dependent variation of pore solution and solid-phase composition in concrete. Multi-species transport approaches, based on the Poisson–Nernst–Planck (PNP) theory alone, not involving chemical processes, have no real practical interest since the chemical action is very dominant for cement based materials. Coupled mass transport and chemical equilibrium models can be used to calculate the variation in pore solution and solid-phase composition when using different types of cements. For example, the physicochemical evaluation of steel corrosion initiation can be studied by calculating the molar ratio of chloride ion to hydroxide ion in the pore solution. The model can, further, for example, calculate changes of solid-phase composition caused by the penetration of seawater into the concrete cover. The mass transport part of the model is solved using a non-linear finite element approach adopting a modified Newton–Raphson technique for minimizing the residual error at each time step of the calculation. The chemical equilibrium part of the problem is solved by using the PHREEQC program. The coupling between the transport part and chemical part of the problem is tackled by using a sequential operator splitting technique and the calculation results are verified by comparing the elemental spacial distribution in concrete measured by the electron probe microanalysis (EPMA).

KW - PHREEQC

KW - Thermodynamic phase equilibrium

KW - Mass transport

KW - Multi-species

KW - [Cl-]/[OH-]

U2 - 10.1617/s11527-011-9720-2

DO - 10.1617/s11527-011-9720-2

JO - Materials and Structures

JF - Materials and Structures

SN - 1359-5997

IS - 9

VL - 44

SP - 1577

EP - 1592

ER -