INFLUENCE OF DUCTILITY AND MICROCRACKING ON THE FROST DURABILITY OF CEMENTITIOUS COMPOSITES WITH HIGH VOLUMES OF FLY ASH

Author: Gurkan Yildirim, Oguzhan Ozturk, Mustafa Sahmaran, Mohamed Lachemi
Paper category: Proceedings
Book title: Proceedings of the International RILEM Conference on Materials, Systems and Structures in Civil Engineering Conference Segment on Frost Action in Concrete
Editor(s): Marianne Tange Hasholt, Katja Fridh and R. Doug Hooton
ISBN:978-2-35158-182-7
e-ISBN:978-2-35158-183-4
Publisher:RILEM Publications SARL
Publication year:2016
Pages:232-241
Total Pages:10
Language:English

Abstract: In the present paper, effects of utilizing high volumes of fly ash (FA) and poly-vinyl-alcohol (PVA) fibers on the freeze-thaw resistance of Engineered Cementitious Composites (ECC) have been investigated. Three different ECC mixtures with FA-cement (FA/C) ratios of 1.2, 2.2 and 4.2 were manufactured at a constant water to cementitious materials ratio of 0.27. For comparison, identical mixtures without PVA (matrix) were produced as well. Frost resistance was evaluated after exposing the mixtures up to 300 freeze-thaw cycles following ASTM C666, Procedure A. Performance assessment has been made by residual flexural properties (flexural strength, mid-span beam deflection and flexural stress - deflection curve), ultrasonic pulse velocity and mass loss. The air-void characteristics of mixtures were also studied using linear transverse method. Test results confirm that ECC mixtures with high volumes of FA remain durable, and show a tensile strain capacity of more than 2% even after 300 freezing and thawing cycles. On the other hand, before completing 300 freezing and thawing cycles, matrix (ECC without fiber) specimens have severely deteriorated. Thus, results indicate that the addition of micro PVA fibers into the ECC matrix substantially improved the frost resistance. The results of freeze-thaw tests also showed that the reduction of residual physical and mechanical properties with increasing number of freeze-thaw cycles increases with the
increase in FA/C ratio.

Online publication:2016
Publication type:full_text
Public price (Euros):0.00