Mercury intrusion porosimetry

Effect of the densification of C–S–H on hydration kinetics of tricalcium silicate

“…Both EDS and WDS measurements indicate an increase in C/S ratio with a decrease in w/c. The trend corresponds well with the literature where the variations in w/c are significantly high . However, our results are not conclusive owing to the large standard deviation.…”

Hydration of Binary Portland Cement Blends Containing Silica Fume: A Decoupling Method to Estimate Degrees of Hydration and Pozzolanic Reaction

“…Several well-established methods for studying hydration kinetics and microstructure evolution of plain portland cement have been developed. The degree of hydration can be routinely monitored/determined using one, or a combination, of several experimental approaches, such as measurement of heat of hydration (Wadsö, 2015;Lapeyre and Kumar, 2018), quantification of non-evaporable water and calcium hydroxide (CH) contents with thermogravimetric analysis (TGA) (Powers and Brownyard, 1946;Fagerlund, 2009;Ma and Li, 2013;Lothenbach et al, 2015), quantitative phase analysis with powder x-ray diffraction (XRD) (Snellings, 2015), and backscattered electron (BSE) image analysis (Scrivener et al, 2016). The microstructure and phase assemblage of hardened pastes can be characterized using mercury intrusion porosimetry (MIP) (Ma, 2014), nitrogen adsorption (Escalante-Garcia, 2003), BSE image analysis (Scrivener et al, 2016), etc.…”

“…The degree of hydration can be routinely monitored/determined using one, or a combination, of several experimental approaches, such as measurement of heat of hydration (Wadsö, 2015;Lapeyre and Kumar, 2018), quantification of non-evaporable water and calcium hydroxide (CH) contents with thermogravimetric analysis (TGA) (Powers and Brownyard, 1946;Fagerlund, 2009;Ma and Li, 2013;Lothenbach et al, 2015), quantitative phase analysis with powder x-ray diffraction (XRD) (Snellings, 2015), and backscattered electron (BSE) image analysis (Scrivener et al, 2016). The microstructure and phase assemblage of hardened pastes can be characterized using mercury intrusion porosimetry (MIP) (Ma, 2014), nitrogen adsorption (Escalante-Garcia, 2003), BSE image analysis (Scrivener et al, 2016), etc. Based on experimental results and/or theoretical hydration kinetics, computer models, such as HYMOSTRUC (van Breugel, 1995a,b), the multi-component model (Kishi and Maekawa, 1996), CEMHYD3D (Bentz et al, 1998), and µic (Bishnoi and Scrivener, 2009;Kumar et al, 2012), have been developed to describe the hydration process of cement and/or microstructural development of cement paste.…”

Optimization of SEM-EDS to determine the C–A–S–H composition in matured cement paste samples

“…A summary of guidelines regarding data acquisition and data treatment is given in the conclusions. The use of electron microscopy for the study of cement and concrete is discussed more extensively in [16] and the reader is referred to this reference for a more detailed practical approach to sample preparation and chemical analyses of cement pastes by both SEM-EDS and TEM-EDS.…”

“…To ensure the best choice of points, the magnification should be relatively high. It should typically be at least ≈ 4000× in the FEI Quanta 200 SEM (horizontal field-of-view of ≈ 60 μm) and ≈ 60,000× in the FEI Tecnai Osiris TEM (horizontal field-of-view of ≈ 1.8 μm).Based on our experience[16], a representative dataset of SEM-EDS analyses can be obtained by measuring no more than 20 points in each of about 10 different zones across the sample and at high magnification. The goal is to record about 100 points for the IP C-A-S-H and at least 100 points for the OP C-A-S-H.…”