Density mapping of hardened cement paste using ptychographic X-ray computed tomography

Abstract Ptychographic X-ray computed tomography (PXCT) allows for a non-destructive, three-dimensional mapping of the electron density. Its quantitativeness combined with a resolution in the 100 nm range makes it a suitable tool for the assessment of densities of the individual phases in complex materials, such as hardened cement pastes. Here we present results of an experiment performed on a cylindrical sample of epoxy-impregnated hardened cement paste of about 30 μm in diameter. Two-dimensional cross sections of the three-dimensional electron density map show a microstructure that bears distinct similarity to that observed by back-scattered scanning electron microscopy. Domains of various residues of cement grains, calcium hydroxide, calcium carbonate, epoxy-resin impregnated calcium silicate hydrates, epoxy-resin impregnated porosity, and unimpregnated porosity are revealed and are manifested as distinguishable peaks in the histogram of the three-dimensional electron density map. On assumptions of (i) a priori knowledge of the chemical composition and (ii) the purity of the analysed regions, the mass densities of the above mentioned individual material phases are estimated. The potential of PXCT for the science of cement and concrete is discussed.

[1]  M. Endo,et al.  Distribution of electron density using dual-energy X-ray CT , 2003 .

[2]  B. Lothenbach,et al.  Thermodynamic modelling of the hydration of Portland cement , 2006 .

[3]  Anders Kaestner,et al.  Spatiotemporal computed tomography of dynamic processes , 2011 .

[4]  D. Jeulin,et al.  Determination of the size of the representative volume element for random composites: statistical and numerical approach , 2003 .

[5]  A. G. Cullis,et al.  Hard-x-ray lensless imaging of extended objects. , 2007, Physical review letters.

[6]  Michael N. Fardis,et al.  FUNDAMENTAL MODELING AND EXPERIMENTAL INVESTIGATION OF CONCRETE CARBONATION , 1991 .

[7]  L. Struble,et al.  Epoxy impregnation of hardened cement for microstructural characterization , 1989 .

[8]  D. Bentz.  Cement hydration: building bridges and dams at the microstructure level , 2006 .

[9]  Gerry McDermott,et al.  X-ray tomography of whole cells. , 2005, Current opinion in structural biology.

[10]  Denis Damidot,et al.  Thermodynamic modelling: state of knowledge and challenges , 2010 .

[11]  B Münch,et al.  Focussed ion beam nanotomography reveals the 3D morphology of different solid phases in hardened cement pastes , 2011, Journal of microscopy.

[12]  J. Rodenburg,et al.  Movable aperture lensless transmission microscopy: a novel phase retrieval algorithm. , 2004, Physical review letters.

[13]  O. Bunk,et al.  High-Resolution Scanning X-ray Diffraction Microscopy , 2008, Science.

[14]  Subra Suresh,et al.  Measuring single-cell density , 2011, Proceedings of the National Academy of Sciences.

[15]  H. Becker,et al.  Ion beam analysis of the hydration of tricalcium silicate , 2003 .

[16]  Magdalena Balonis,et al.  The density of cement phases , 2009 .

[17]  P. Cloetens,et al.  Sub-micrometer synchrotron tomography of multiphase metals using Kirkpatrick–Baez optics , 2009 .

[18]  S. Manalis,et al.  Weighing of biomolecules, single cells and single nanoparticles in fluid , 2007, Nature.

[19]  O. Bunk,et al.  Ptychographic X-ray computed tomography at the nanoscale , 2010, Nature.

[20]  S. Bakke,et al.  Process Based Reconstruction of Sandstones and Prediction of Transport Properties , 2002 .

[21]  Josef Kaufmann,et al.  On the use of peak-force tapping atomic force microscopy for quantification of the local elastic modulus in hardened cement paste , 2012 .

[22]  O. Bunk,et al.  Quantitative x-ray phase nanotomography , 2012 .

[23]  A. Mozzanica,et al.  Characterization and Calibration of PILATUS Detectors , 2009, IEEE Transactions on Nuclear Science.

[24]  Michael Angelo B. Promentilla,et al.  Quantification of Tortuosity in Hardened Cement Pastes using Synchrotron-based X-ray Computed Microtomography , 2009 .

[25]  B Münch,et al.  Three‐dimensional analysis of porous BaTiO3 ceramics using FIB nanotomography , 2004, Journal of microscopy.

[26]  Karen L. Scrivener,et al.  Backscattered electron imaging of cementitious microstructures: Understanding and quantification , 2004 .

[27]  Marco Stampanoni,et al.  Quantification of a single aggregate inner porosity and pore accessibility using hard X-ray phase-contrast nanotomography. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[28]  K. Mecke,et al.  3D structural analysis: sensitivity of Minkowski functionals , 2010, Journal of microscopy.

[29]  J. Wagner,et al.  Automated three-dimensional X-ray analysis using a dual-beam FIB. , 2007, Ultramicroscopy.

[30]  O. Bunk,et al.  Phase tomography from x-ray coherent diffractive imaging projections. , 2011, Optics express.

[31]  John L. Provis,et al.  Hard x-ray nanotomography of amorphous aluminosilicate cements. , 2011 .

[32]  K. Kurtis,et al.  Investigation of alkali-silica reaction by transmission soft x-ray microscopy , 2000 .

[33]  Marco Stampanoni,et al.  Phase-contrast tomography at the nanoscale using hard x rays , 2010 .

[34]  Jeffrey J. Thomas,et al.  Composition and density of nanoscale calcium-silicate-hydrate in cement. , 2007, Nature materials.

[35]  Hamlin M. Jennings,et al.  Refinements to colloid model of C-S-H in cement: CM-II , 2008 .

[36]  P. Monteiro,et al.  Nanostructure of calcium silicate hydrates in cements. , 2010, Physical review letters.

[37]  Andreas Menzel,et al.  Probe retrieval in ptychographic coherent diffractive imaging. , 2009, Ultramicroscopy.

[38]  Frank Winnefeld,et al.  Influence of cement ageing and addition time on the performance of superplasticizers , 2008 .

[39]  Robert J. Flatt,et al.  Dissolution theory applied to the induction period in alite hydration , 2010 .