118. Microstructure and durability of self-compacting concretes containing PP fibres

Title: 118. Microstructure and durability of self-compacting concretes containing PP fibres
Author(s): M. Kalinowski, J. Trägårdh
Paper category : conference
Book title: 5th International RILEM Symposium on Self-Compacting Concrete
Editor(s): G. De Schutter and V. Boel
Print-ISBN: 978-2-35158-047-9
e-ISBN: 978-2-35158-088-2
Publisher: RILEM Publications SARL
Publication year: 2007
Pages: 785 - 792
Total Pages: 8
Nb references: 7
Language: English

Abstract: 8 SCC mixes with CEM I (w/c ratio 0.40), CEM II (w/c ratio 0.65) and different amounts of PP fibres were prepared for the study as well as reference samples of the same SCC mixes but without PP fibres. Two diameters of PP fibres were used, Ø=18 µm and Ø=32µm, both with a length of 6 mm. A study of the fibre distribution showed a homogenous distribution in the hardened concretes. From a microstructure study with SEM/EDS it was found that the surface of PP fibres favours nucleation of portlandite crystals, analogous with the precipitation of portlandite on filler particles. In SCC with w/c ratio of 0.40 the framework of portlandite crystals around the PP fibres forms relatively dense interfacial transition zones (ITZ) between the fibres and the cement paste, which seem to decrease the permeability of the concretes. The opposite seem to be the case for SCC with w/c ratio 0.65. Apart from the study of the ITZ, the investigation includes measurements of capillary transport, chloride diffusion, salt-frost scaling and air void distribution.

Online publication: 2009-06-16
Publication type : full_text
Public price (Euros): 0.00