Publications

Pro083

Polymer action on corrosion rates of steel in cement mortar



Author(s): T.N. Dias, M.S. Ribeiro, O.A. Pereira, E.M. Pereira, J.L. Feiteira
Paper category: Conference
Book title: 2nd International conference on Microstructural-related Durability of Cementitious Composites
Editor(s): Guang Ye, K. Van Breugel, Wei Sun, Changwen Miao
Print ISBN: 978-2-35158-129-2
e-ISBN: 978-2-35158-123-0
Publisher: RILEM Publications SARL
Pages: 1500- 1510
Total Pages: 10
Language: English


Abstract: 
Polymer cement mortars (PCMs) are traditional mortars with a new component, the polymer, which is added to the mixing water to modify their properties. PCMs have been increasingly used for the repair of reinforced concrete structures, mainly due to their improved adhesion and reduced water absorption. Higher electric resistivity and a higher resistance to carbonation are also expected, thus leading to a potential increased resistance to corrosion of steel embedded in PCMs.

This paper reports both the general concepts associated with polymer modification of cement mortar (CM) and the results of an experimental investigation into the action of styrene-butadiene and acrylic-styrene polymer additions on the corrosion rate of steel embedded in carbonated CM. Air content, mechanical strength, water absorption, resistance to carbonation, and electrical resistivity of PCMs were determined as well as the corrosion current of steel embedded in carbonated mortar in high humidity environments. The microstructure of the corrosion products formed in steel rebars embedded in PCMs was characterised by scanning electron microscopy (SEM).

Results confirmed a noticeable reduction in the corrosion rate of steel rebars embedded in carbonated PCMs comparatively to unmodified CM. The physical barrier created by the polymer film in the polymer cement co-matrix, which reduces ionic mobility and water absorption, is pointed out as the main explanation for the potential of polymer additions in reducing corrosion rates.


Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00