Pore-scale modelling of 3D moisture distribution and critical saturation in cementitious materials

Abstract The understanding and prediction of moisture distribution and critical moisture content above which fluid and ion transport can occur in porous media is of significant technological importance. A novel computational methodology for simulating moisture distribution and calculating critical content in 3D images of microstructures is presented. The method accounts for the liquid–gas interaction and liquid/gas–solid interaction at the pore scale. Microstructures of cement pastes at different curing ages, obtained by high-resolution X-ray micro-computed tomography, are analyzed. The equilibrium moisture distribution in the 3D microstructures is acquired. The degree of connectivity of the liquid and gas phases is calculated as a function of water saturation level. The critical water saturation for each phase is obtained. It is shown that the moisture distribution and connectivity of each phase depend strongly not only on the degree of water saturation but also on the structures of the pore space and the solid phase. The critical water saturation increases with the decrease of porosity. The results from the simulations are in very good agreement with the experimental data reported in the literature. The proposed methodology is applicable to image-based modelling of all porous media.

[1]  C. Pan,et al.  Lattice‐Boltzmann simulation of two‐phase flow in porous media , 2004 .

[2]  I. Ioannou,et al.  In-situ measurement of liquid phase moisture in cement mortar , 2012 .

[3]  Mingzhong Zhang,et al.  Multiscale lattice Boltzmann-finite element modelling of chloride diffusivity in cementitious materials. Part II: Simulation results and validation , 2014 .

[4]  J. Carmeliet,et al.  Moisture transfer through mortar joints: A sharp-front analysis , 2012 .

[5]  L. Nilsson,et al.  A method to determine the critical moisture level for unsaturated transport of ions , 2015 .

[6]  K. You,et al.  Determination of Moisture Content in Mortar at Near Relaxation Frequency 17 GHz , 2011 .

[7]  Shan,et al.  Lattice Boltzmann model for simulating flows with multiple phases and components. , 1993, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[8]  Mingzhong Zhang,et al.  A numerical-statistical approach to determining the representative elementary volume (REV) of cement paste for measuring diffusivity , 2010 .

[9]  K. Van Breugel,et al.  Simulation of hydration and formation of structure in hardening cement-based materials , 1991 .

[10]  Xiaowen Shan,et al.  Multicomponent lattice-Boltzmann model with interparticle interaction , 1995, comp-gas/9503001.

[11]  C. Andrade,et al.  A test method for measuring chloride diffusion coefficients through partially saturated concrete. Part II: The instantaneous plane source diffusion case with chloride binding consideration , 2007 .

[12]  Dale P Bentz,et al.  CEMHYD3D:: a three-dimensional cement hydration and microstructure development modelling package , 1997 .

[13]  Mingzhong Zhang,et al.  Modeling of ionic diffusivity in non-saturated cement-based materials using lattice Boltzmann method , 2012 .

[14]  M. R. Yeung,et al.  Effect of water saturation on deterioration of welded tuff due to freeze-thaw action , 2004 .

[15]  C. Andrade,et al.  A test method for measuring chloride diffusion coefficients through nonsaturated concrete. Part I. The instantaneous plane source diffusion case , 2002 .

[16]  Michael D.A. Thomas,et al.  Embedded NMR sensors to monitor evaporable water loss caused by hydration and drying in Portland cement mortar , 2009 .

[17]  Guang Ye,et al.  Experimental Study and Numerical Simulation of the Development of the Microstructure and Permeability of Cementitious Materials , 2003 .

[18]  C. Andrade,et al.  Determination of chloride diffusivity through partially saturated Portland cement concrete by a simplified procedure , 2011 .

[19]  Y. Qian,et al.  Lattice BGK Models for Navier-Stokes Equation , 1992 .

[20]  J. Dolado,et al.  Recent advances in modeling for cementitious materials , 2011 .

[21]  Nicos Martys,et al.  Diffusion in partially-saturated porous materials , 1999 .

[22]  Andrey P. Jivkov,et al.  Microstructure-informed modelling of damage evolution in cement paste , 2014 .

[23]  Laura Schaefer,et al.  Equations of state in a lattice Boltzmann model , 2006 .

[24]  F. Wittmann,et al.  Visualization and quantification of water movement in porous cement-based materials by real time thermal neutron radiography: Theoretical analysis and experimental study , 2010 .

[25]  Mingzhong Zhang,et al.  Microstructure-based modeling of permeability of cementitious materials using multiple-relaxation-time lattice Boltzmann method , 2013 .

[26]  Raoul Kopelman,et al.  Percolation and cluster distribution. I. Cluster multiple labeling technique and critical concentration algorithm , 1976 .

[27]  M. Zhang Multiscale Lattice Boltzmann-Finite Element Modelling of Transport Properties in Cement-based Materials` , 2013 .

[28]  S. Lorente,et al.  Ionic aqueous diffusion through unsaturated cementitious materials – A comparative study , 2014 .

[29]  B. Bissonnette,et al.  EARLY-AGE EVOLUTION OF THE MASS TRANSFER PROPERTIES IN MORTAR AND ITS INFLUENCE UPON ULTIMATE SHRINKAGE , 2010 .

[30]  S. Lorente,et al.  Influence of the pore network on hydrogen diffusion through blended cement pastes , 2013 .

[31]  A. Jivkov,et al.  Meso-scale site-bond model for elasticity: theory and calibration , 2014 .

[32]  Guang Ye,et al.  Computational investigation on mass diffusivity in Portland cement paste based on X-ray computed microtomography (μCT) image , 2012 .

[33]  S. Lorente,et al.  Architecture for gas transport through cementitious materials , 2009 .

[34]  F. Derkx,et al.  Determination of relevant parameters influencing gas permeability of mortars , 2011 .

[35]  Shan,et al.  Simulation of nonideal gases and liquid-gas phase transitions by the lattice Boltzmann equation. , 1994, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.