The pore structure and water permeability of cement paste blended with fly ash over a long period up to one year

Author(s): Z. Yu, G. Ye
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: 108 – 109
Total Pages: 2
Language: English

Abstract: 
As a waste residue, Fly Ash (FA) is widely used in construction. Many researches indicated that although the addition of FA reduces concrete strength at early age, blended concrete shows excellent long-term durability. Permeability is one of the most important properties of concrete for estimating durability of concrete. In general, researches focused on the relation between total porosity and water permeability, in most case the curing age was limited to a short-term period. The objective of this paper is to investigate the development of pore structure and its influence on water permeability over a longterm period up to one year, when FA is used as supplement cemetitious materials. In this paper, different contents of FA (30% and 50%) and two different water to binder ratios (w/b ratios) (0.4 and 0.5) were adopted to measure the water permeability and pore structure of blended cement pastes with FA. To explore the relation between pore structure and water permeability, Mercury Intrusion Porosimetry (MIP) method was conducted to obtain the total porosity and pore size distribution of blended cement paste. Direct test method, which is the monitoring of a steady flow through saturated specimens under a hydrostatic pressure gradient, was performed to determine the water permeability of the cement pastes blended with FA. The test results show that the total porosity is not the only factor which can influence the water permeability of pastes. The pore size distribution and critical pore also impact the water permeability of blended cement pastes.

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