Characteristics and durability of environment-conscious concrete with a high volume of fly ashes

Title: Characteristics and durability of environment-conscious concrete with a high volume of fly ashes
Author(s): B. Gert
Paper category : conference
Book title: RILEM International Symposium on Environment-Conscious Materials and Systems for Sustainable Development
Editor(s): N. Kashino and Y. Ohama
Print-ISBN: 2-912143-55-1
e-ISBN: 2912143640
Publisher: RILEM Publications SARL
Publication year: 2004
Pages: 103 - 110
Total Pages: 8
Nb references: 5
Language: English

Abstract: The concrete industry significantly contributes to the emission of greenhouse gasses, especially CO2 which is emitted during the cement production. More than 56% of this CO2-emission is caused by the thermal decomposition of CaCO3 into CaO and CO2 during the sintering process of Portland clinker. International agreements, such as the Kyoto Protocol, result in an increased pressure to produce and use environment-conscious materials. One way to reduce CO2-emissions would be to produce concrete with a high volume of fly ash, which is a waste product. Concrete samples with 10%, 40% and 60% replacement of cement by fly ash were produced, using 2 different fly ash types and an appropriate amount of (super)plasticiser to obtain good workability. The compressive strength decreased at young age with increasing level of cement replacement. The fly ashes had a positive effect on chemical aggression by organic and sulphuric acid, and on chloride diffusion, but on the other hand a negative influence on the resistance against carbonation and against the combined action of frost and de-icing salt. The results show that high volume fly ash concrete has a potential for commercial use, especially in particular applications.

Online publication: 2004-11-24
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/2912143640.012