Effect of Replacement of Silica Fume with Calcined Clay on The Hydration and Microstructural Development of Ulta-High Performance Concrete

Author(s): Wei Huang, Hadi Kazemi-Kamya, Wei Sun, Karen Scrivener
Paper category: Proceedings
Book title: 1st International Conference on UHPC Materials and Structures
Editor(s): Caijun Shi and Dehui Wang
ISBN: 978-2-35158-164-3
e-ISBN: 978-2-35158-165-O
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 403-408
Total Pages: 06
Language: English

Abstract: Clays with moderate kaolinite content are available in many places in the world and the demand for their use is low; thus calcined clays with lower grade kaolinite can possibly be an attractive substitute for silica fume, making ultra-high performance concrete (UHPC) more economical and ecological. In this paper, the influence of substitution of silica fume by two grades of calcined clay on the hydration and microstructural development of a UHPC was investigated,
where 54% of the cement by volume has already been replaced by a limestone with similar PSD. It was seen that comparable UHPC’s were obtained when silica fume was replaced with calcined clay by volume. The experimental results revealed that the competition for consumption of water, between the cement hydration and pozzolanic/synergic reaction of kaolinite to form more AFt and AFm phases was critical on the development of hydration and
compressive strength of UHPC’s with calcined clays.

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