Preliminary study of Electrochemical lithium migration into cementitious mortar

Title: Preliminary study of Electrochemical lithium migration into cementitious mortar
Author(s): Jose Pacheco Farias, Rob B. Polder
Paper category : conference
Book title: 2nd International Symposium on Service Life Design for Infrastructures
Editor(s): K. van Breugel, Guang Ye, Yong Yuan
Print-ISBN: 978-2-35158-096-7
e-ISBN: 978-2-35158-097-4
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 1093 - 1100
Total Pages: 8
Nb references: 16
Language: English

Abstract: Alkali-Silica Reaction (ASR) is a deleterious process that decreases significantly the durability of concrete structures. It is due to a reaction between hydroxides derived from cement alkalis (Na2O and K2O) and (non or poorly crystalline) siliceous minerals from aggregates. As a result, an expansive gel of alkali-silicates is formed in weak planes and pores in the matrix or in the aggregate/paste interface. Consequently, the concrete may crack or the bond between paste and aggregates is broken. Research has shown that the presence of lithium ions in the cement matrix leads to the formation of a non-expansive ASR gel.
Nevertheless, the effect of lithium on ASR has been mainly studied as an addition to newly cast concrete. This paper reports a preliminary study of electromigration of lithium ions into cementitious mortar. Results show that the electrical current passing through the specimens was time-dependent, the final lithium content depends of the electrical force (voltage) applied and the lithium content in the first 10 mm reached levels between 700 and 1000 ppm after four weeks.

Online publication: 2011-04-20
Publication type : full_text
Public price (Euros): 0.00