The influence of air voids on the properties of self-compacting concretes containing fly ash

Title: The influence of air voids on the properties of self-compacting concretes containing fly ash
Author(s): W. Brameshuber, S. Uebachs
Paper category : conference
Book title: International RILEM Symposium on Self-Compacting Concrete
Editor(s): O. Wallevik and I. Nielsson
Print-ISBN: 2-912143-42-X
e-ISBN: 2912143713
Publisher: RILEM Publications SARL
Publication year: 2003
Pages: 870 - 880
Total Pages: 11
Nb references: 17
Language: English

Abstract: To ensure a practicable freeze-thaw and de-icing salt resistance, an artificial air void system with a defined geometric structure (micro air void volume, spacing factor) is needed in concrete giving space for expansion in the pore structure. Thus, the concrete is enabled to take up the volume extension of the freezing water without suffering any damage. The formation of micro air voids is induced by air entraining agents. In the case of Self-Compacting Concrete (SCC) it became obvious that the artificially created air voids do not only influence the durability of the concrete, furthermore, they even change the rheological properties of the fresh SCC. Moreover, it became apparent that the incorporation and the stability of an artificial air void system in SCC is complicated by a number of concrete-technological and environmental factors. E. g. the formation of an air void system in SCC with even a high consistency using a superplasticizer on the basis of a polycarboxylate-ether cannot always be achieved without difficulties. In this paper the results of these investigations concerning the properties of fresh and hardened SCC are presented.

Online publication: 2003-08-21
Publication type : abstract_only
Public price (Euros): 0.00