Mix design optimisation - the influence of binder content on mechanical and durability properties of concrete

Author(s): M. Angelucci, H. Beushausen, M.G. Alexander
Paper category: Conference
Book title: Concrete Repair, Rehabilitation and Retrofitting III (ICCRRR)
Editor(s): M.G. Alexander, H.-D. Beushausen, F. Dehn, P. Moyo
Print ISBN: 978-0-415-89952-9
Publisher: Taylor & Francis Group
Pages: 150 – 151
Total Pages: 2
Language: English

Abstract: 
Current mix design standards mainly derive from prescriptive type specifications, i.e. recipe-based specifications that prescribe limiting values for certain mix design parameters, such as minimum cement content and maximum water/binder ratio. This has numerous economical, technical and environmental disadvantages and is one of the driving factors behind the development of performancebased specifications to act as alternative means of design of concrete mixes. Such an alternative method in South Africa is the Durability Index (DI) Approach, which has grown increasingly in use. Despite this, a dominant assumption among professionals in the industry is that the durability of a concrete mixture is directly proportional to its binder content. This results in uneconomical, unsustainable and often nondurable concretes due to various implications of high cement contents such as thermal effects and Alkali-Silica reactions. This paper forms part of research that will link mix design parameters such as binder content and water/binder ratio, as well as mechanical properties such as compressive strength, to concrete durability. Issues behind the specification of minimum cement contents are investigated through a review of various pertinent studies conducted previously, followed by a summary of experimental results conducted by the first author. The results gathered in this document suggest that the relationship between durability and binder content is a complex one and hence the specification of minimum cement contents is not an effective means of ensuring durability and should be revisited.

Online publication: 2014
Publication Type: abstract_only
Public price (Euros): 0.00