TITLE:
Influence of Microstructural Changes on Some Macro Physical Properties of Cement Mortar during Accelerated Carbonation
AUTHORS:
Son Tung Pham
KEYWORDS:
Carbonation, Cement Mortar, Microstructure, Nitrogen Adsorption, Gas Permeability, Thermal Conductivity
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.4 No.2,
May
15,
2014
ABSTRACT:
The objective of
this work was to examine the changes in the microstructure and macro physical
properties caused by the carbonation of normalised CEM II mortar. Samples were
prepared and subjected to accelerated carbonation at 20°C, 65% relative
humidity and 20% CO2 concentration. On the microstructure scale, the
evolutions of the cumulative pore volume, pore size distribution, and specific
surface area during carbonation were calculated from the adsorption desorption
isotherms of nitrogen. We also examined the evolution of macro physical properties
such as the solid phase volume using helium pycnometry, porosity accessible to
water, gas permeability, and thermal conductivity. The conflict between
nitrogen porosity and water porosity results indicated that the porous domains
explored using these two techniques are different and help to complementarily
evaluate the effects of carbonation. This is a multi-scale study where results
on microstructural changes can help to explain the evolution of macro physical
properties.