Time-resolved porosity changes at cement-clay interfaces derived from neutron imaging

Shafizadeh, A; Gimmi, T.; Van Loon, LR; Kaestner, AP; Mäder, U. K.; Churakov, S. V. (2020). Time-resolved porosity changes at cement-clay interfaces derived from neutron imaging. Cement and concrete research, 127, p. 105924. Elsevier 10.1016/j.cemconres.2019.105924

Preview	Text Shafizadeh_etal_accepted.pdf - Accepted Version Available under License Creative Commons: Attribution-Noncommercial-No Derivative Works (CC-BY-NC-ND). Download (2MB) | Preview
	Text Shafizadeh_etal_2020_CCR.pdf - Published Version Restricted to registered users only Available under License Publisher holds Copyright. Download (3MB)

Interfaces between cement and clay are common in engineered barrier systems for the underground disposal of radioactive waste. The geochemical contrast between clay and cement leads to alterations of both materials following dissolution and precipitation reactions. Porosity is a key parameter for, and a key outcome of, such reactive transport. Here we report on the evolution of porosity within small samples made from ordinary portland cement and Na montmorillonite. Water contents, a proxy for porosity in saturated samples, were derived from neutron imaging. Specific calibration procedures were developed to account for multiple scattering effects. An increase in cement porosity was observed propagating similar to 2 mm away from the interface within 600 days, and a considerable decrease in clay porosity within similar to 2 mm. Our experiments provide unique information on the dynamics of the processes up to nearly two years. The data set provides valuable input to better constrain reactive transport models.

Interest & Impact

Downloads

95 since deposited on 03 Apr 2020
36 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item