EVOLUTION OF THE CEMENT MORTAR MICROSTRUCTURE CAUSED BY SALT CRYSTALLIZATION AND WATER FREEZING INVESTIGATED BY MULTICYCLE MERCURY INTRUSION POROSIMETRY
Author(s): Grymin, W., Koniorczyk, M., Konca, P., Marciniak, A. and Gawin, D.
Paper category: Conference
Book title: XIII International Conference on Durability of Building Materials and Components - XIII DBMC
Editor(s): Marco Quattrone, Vanderley M. John
Print ISBN: none
Publication year: 2015
Total Pages: 8
Abstract: The paper presents application of the Multi-cycle Mercury Intrusion Porosimetry for analyzing the evolution of the cement mortar microstructure due to the sodium sulphate crystallization and cyclic water freezing. The influence of the above mentioned degradation processes was investigated for several types of mortar, recipes of which differed with the content of an air-entraining admixture (AEA) and w/c ratio. Cumulative pore volume was measured for two cycles of intrusion-extrusion in order to calculate the contribution of inkbottle type pores. The most severe damage caused by the sodium sulphate crystallization was observed for the mortar without any AEA addition – the pores of diameter 0.2-60μm increased their volume up to 250%. In the samples containing 0.1% and 0.2% of AEA the pores of diameter 0.6-30μm increased their volume up to 155%. After the freeze-thaw cycles, smaller damage of the material microstructure was observed also for the mortars containing AEA. Both the salt crystallization and frost-induced damage have an adverse effect on the mortar microstructure, which can be restrained by the addition of AEA.
Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00