Determination of the pH and the free alkali metal content in the pore solution of concrete: Review and experimental comparison

Abstract The durability of concrete is affected by the pH of its pore solution, which is linked to the free alkali metal content. This paper starts with a literature review of methods for determining the pH and/or the free alkali metal content in the pore solution of concrete. Promising methods are compared in the second part of the paper. We then report on pore water expression (PWE) and three ex situ leaching methods (ESL) applied to Portland cement (CEM I) and Portland fly ash cement (CEM II/B-V) mortars. Finally, we make recommendations for the determination of the pH and the free alkali metal content of concrete. Because the measurement of the free-water content of the sample was found to be an important parameter, it is recommended to determine the pH with PWE and the free alkali metal content with ESL.

[1]  Josef Tritthart,et al.  Chloride binding in cement I. Investigations to determine the composition of porewater in hardened cement , 1989 .

[2]  C. Hansson,et al.  Pore solution expression as a method to determine the influence of mineral additives on chloride binding , 1986 .

[3]  A. Sagüés,et al.  In situ leaching method for determination of chloride in concrete pore water , 2006 .

[4]  Sidney Diamond,et al.  Expression and analysis of pore fluids from hardened cement pastes and mortars , 1981 .

[5]  Dale L. Perry,et al.  Handbook of Inorganic Compounds. , 1995 .

[6]  Eric R. Giannini Evaluation of concrete structures affected by alkali-silica reaction and delayed ettringite formation , 2012 .

[7]  Scott R. Charlton,et al.  Modules based on the geochemical model PHREEQC for use in scripting and programming languages , 2011, Comput. Geosci..

[8]  Eric I. Moreno,et al.  Determinación del pH de la solución de los poros de concreto después de un proceso acelerado de carbonatación , 2006 .

[9]  I. Richardson,et al.  Composition and Microstructure of 20-year-old Ordinary Portland Cement-ground Granulated Blast-furnace Slag Blends Containing 0 to 100% Slag , 2010 .

[10]  Mitsunori Kawamura,et al.  EVALUATION OF THE DEGREE OF DETERIORATION IN ASR DAMAGED CONCRETES AND ANALYSES OF THEIR PORE SOLUTIONS , 2000 .

[11]  Ionel Michael Navon,et al.  VARIATM—A FORTRAN program for objective analysis of pseudostress wind fields using large-scale conjugate-gradient minimization , 1991 .

[12]  Patrice Rivard,et al.  High-Pressure Device for Fluid Extraction from Porous Materials: Application to Cement-Based Materials , 2008 .

[13]  G. E. Monfore Propiedades de los cementos expansivos, hechos con cemento portland, yeso y cemento aluminoso , 1966 .

[14]  E. L'Hôpital Aluminium and alkali uptake in calcium silicate hydrates (C-S-H) , 2014 .

[15]  Kenneth T. V. Grattan,et al.  Fluorescence based fibre optic pH sensor for the pH 10–13 range suitable for corrosion monitoring in concrete structures , 2014 .

[16]  G. Saoût,et al.  Hydration mechanisms of ternary Portland cements containing limestone powder and fly ash , 2011 .

[17]  F. Frizon,et al.  Retention of alkali ions by hydrated low-pH cements: Mechanism and Na+/K+ selectivity , 2013 .

[18]  V. Pavlík Water extraction of chloride, hydroxide and other ions from hardened cement pastes , 2000 .

[19]  Kenneth T. V. Grattan,et al.  Fiber optic chemical sensor systems for monitoring pH changes in concrete , 2004, SPIE Optics East.

[20]  O. A. Kayyali,et al.  Free and water soluble chloride in concrete , 1995 .

[21]  Marta Castellote,et al.  Alkaline leaching method for the determination of the chloride content in the aqueous phase of hardened cementitious materials , 2001 .

[22]  A. Nonat,et al.  The Structure, Stoichiometry and Properties of C-S-H Prepared by C3S Hydration Under Controlled Condition , 1998 .

[23]  K. Krebber,et al.  Fiber-optic sensor applications in civil and geotechnical engineering , 2011 .

[24]  Gilles Plusquellec Analyse in situ de suspensions de silicate de calcium hydraté : application aux interactions ioniques à la surface des particules , 2014 .

[25]  C. L. Page,et al.  Pore solution composition and chloride binding capacity of silica-fume cement pastes , 1983 .

[26]  R. Snellings,et al.  The pore solution of blended cements: a review , 2016 .

[27]  William H. Hartt,et al.  Ex situ leaching measurement of concrete alkalinity , 2005 .

[28]  Marc-André Bérubé,et al.  Laboratory assessment of alkali contribution by aggregates to concrete and application to concrete structures affected by alkali-silica reactivity , 2002 .

[29]  Luca Bertolini,et al.  Corrosion of Steel in Concrete , 2013 .

[30]  Alberto A. Sagüés,et al.  In situ leaching investigation of pH and nitrite concentration in concrete pore solution , 1999 .

[31]  M. Castellote,et al.  Determinación del contenido de OH en la fase acuosa de los poros de matrices cementantes por un método empírico de lixiviación , 2002 .

[32]  Carmen Andrade,et al.  Evolution of pH during in-situ leaching in small concrete cavities , 1997 .

[33]  Wolfgang Kowalsky,et al.  A novel fabrication method of fiber-optical planar transmission sensors for monitoring pH in concrete structures , 2008 .

[34]  Karen L. Scrivener,et al.  A Practical Guide to Microstructural Analysis of Cementitious Materials , 2015 .

[35]  Marc-André Bérubé,et al.  Measurement of the Alkali Content of Concrete Using Hot-Water Extraction , 2002 .

[36]  S. Nagasaki,et al.  Change In Pore Structure And Composition Of Hardened Cement Paste During The Process Of Dissolution , 2005 .

[37]  H. Taylor 726. Hydrated calcium silicates. Part I. Compound formation at ordinary temperatures , 1950 .

[38]  J. Duchesne,et al.  Measurement and prediction of portlandite solubility in alkali solutions , 1995 .

[39]  Thomas Wagner,et al.  GEM-Selektor geochemical modeling package: revised algorithm and GEMS3K numerical kernel for coupled simulation codes , 2012, Computational Geosciences.

[40]  D. McPolin,et al.  Carbonation and pH in Mortars Manufactured with Supplementary Cementitious Materials , 2009 .

[41]  Nele De Belie,et al.  Methods for measuring pH in concrete: A review , 2016 .

[42]  N. S. Rengaswamy,et al.  RELATIONSHIP BETWEEN CHLORIDE/HYDROXIDE RATIO AND CORROSION RATE OF STEEL IN CONCRETE , 1998 .

[43]  Kenneth T. V. Grattan,et al.  Fibre optic chemical sensor systems for internal concrete condition monitoring , 2004, European Workshop on Optical Fibre Sensors.

[44]  Michael D.A. Thomas,et al.  Alkali-silica reaction (ASR)-performance testing: Influence of specimen pre-treatment, exposure conditions and prism size on alkali leaching and prism expansion , 2013 .

[45]  Kenneth T. V. Grattan,et al.  P2.3.16 yFibre optic pH sensor for Corrosion Monitoring in Concrete Structures , 2012 .

[46]  Q. Pu,et al.  Evolution of pH and chemical composition of pore solution in carbonated concrete , 2012 .

[47]  K. Scrivener,et al.  Alkali fixation of C-S-H in blended cement pastes and its relation to alkali silica reaction , 2012 .

[48]  Marc-André Bérubé,et al.  Evaluation of the validity of the pore solution expression method from hardened cement pastes and mortars , 1994 .

[49]  Jie Zhang,et al.  Comparison of methods for arresting hydration of cement , 2011 .

[50]  B. Van der Bruggen,et al.  Influence of molecular size, polarity and charge on the retention of organic molecules by nanofiltration , 1999 .

[51]  Vesa Penttala,et al.  The pH measurement of concrete and smoothing mortar using a concrete powder suspension , 2004 .

[52]  C. Page,et al.  The pore solution phase of carbonated cement pastes , 2005 .