Investigation of the microstructure and mechanism of ultra-high performance cementitios composites

Title: Investigation of the microstructure and mechanism of ultra-high performance cementitios composites
Author(s): X. Zhang, W. Sun, Z. Rong, Q. Zhang
Paper category : conference
Book title: International Conference on Microstructure Related Durability of Cementitious Composites
Editor(s): W. Sun, K. van Breugel, C. Miao, G. Ye and H. Chen
Print-ISBN: 978-2-35158-065-3
e-ISBN: 978-2-35158-084-4
Publisher: RILEM Publications
Publication year: 2008
Pages: 77 - 86
Total Pages: 10
Nb references: 15
Language: English

Abstract: Ultra High Performance Cementitious Composites (UHPCC) with target strength greater than 150Mpa and excellent workability was designed for specific structural application.
Cement content of UHPCC are generally rather high compared to the conventional concrete.
The aim of this study is to decreasing the cement by using 35% fly ash. The compressive strength reached up to 210MPa and flexural strength exceeded 60MPa. The hydration products, microstructure and pore-structure of UHPCC containing fly ash are also investigated by X-ray diffraction (XRD), differential scanning calorimetric-thermogravimetry (DSC-TG), Scanning electron microscope-energy dispersion X-ray analysis (SEM-EDXA),and mercury intrusion porosimetry (MIP). The mechanism of high performance of UHPCC is theoretically discussed. Results show that microstructure of UHPCC was very compacted. The total porosity of UHPCC is much lower than conventional concrete and the diameter of the most pores is less than 30nm. ITZ is improved by pozzolanic reaction of mineral admixture, and calcium hydroxide (CH) was hardly detect. The sound composition and the compact microstructure of the hydration products lead to the excellent properties of UHPCC.

Online publication: 2009-06-09
Publication type : full_text
Public price (Euros): 0.00