INFLUENCE OF DIFFERENT ADMIXTURES ON ULTRA HIGH PERFORMANCE CONCRETE UNDER DIFFERENT CURING CONDITIONS

Author(s): Yuejun Wu, Shuai GAO, Yujie Feng, Weijie Yan, Jingya Zhou
and Junfeng Wang
Paper category: Proceedings
Book title: Proceedings of the 2nd International Conference on UHPC Materials and Structures (UHPC2018-China)
Editor(s): Caijun Shi and Baochun Chen
ISBN: 978-2-35158-219-0
e-ISBN: 978-2-35158-220-6
Publisher: RILEM Publications SARL
Publication year: 2018
Pages: 235-244
Total Pages: 10
Language : English

Abstract: In this work, ultra-high performance concrete (UHPC) was prepared by single-mixing and
compounding of different mineral admixtures such as fly ash (FA), ground granulated blast
furnace slag (GGBFS), and silica fume (SF) curing under different conditions. Differential
thermal analysis (DTA), fourier transform infrared spectroscopy (FTIR), scanning electron
microscopy (SEM), and other analytical methods were used to evaluate the performance of
UHPC. Results indicated that the early strength of UHPC increased with increasing curing
temperature for any mineral admixtures, and the enhancement of silica fume was most
obvious. Moreover, DTA results indicated that the content of Ca(OH)2 (CH) in the UHPC
decreased with increasing curing temperature, which was due to SF quickly react with the
hydration CH at high temperature and consume CH. Furthermore, FTIR results indicated
autoclaved curing accelerated the hydration of the cement in a short period of time,
producing more C-S-H, resulting in the compressive strength increased. Furthermore, SEM
observation indicated that the microstructure of cement pastes became more and more dense
and the porosity decreased with increasing curing temperature.

Online publication : 2018
Publication type : full_text
Public price (Euros) : 0.00