Concrete durability improvement by the use of metakaolin

Author(s): N. Melo, A. Velosa, P. Cachim
Paper category: Workshop
Book title: RILEM International workshop on performance-based specification and control of concrete durability
Editor(s): D. Bjegović, H. Beushausen, M. Serdar
ISBN: 978-2-35158-135-3
e-ISBN: 978-2-35158-136-0
Pages: 75 - 82
Total Pages: 8
Language: English

Abstract: 
Sustainability issues have increased the interest in durability of materials and structures. Concrete is not an exception and in the last years a lot of research has been devoted to this topic. Chloride penetration in concrete is a major cause of corrosion in reinforced concrete structures; hence, its reduction is very important to improve durability. The use of metakaolin in concrete, due to its high alumina content, may contribute to this goal. In this study the effect of metakaolin in the chloride penetration in concrete is evaluated by different methods. Different percentages of cement were replaced by metakaolin (10 and 20%) and workability (slump) of the mixes was kept constant by adding a superplasticizer. Compressive strength, water absorption and ultrasonic pulse velocity were also measured. Results show, as expected, an increase of the compressive strength and stiffness with increasing content of metakaolin. Regarding chloride penetration, a significant reduction is achieved by the use of metakaolin observed in all methods. In addition a numeric model based on second Fick’s Law of diffusion was used to estimate the chloride penetration.

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