Internal relative humidity and autogenous shrinkage of low water/binder ratio concrete

Title: Internal relative humidity and autogenous shrinkage of low water/binder ratio concrete
Author(s): Fazhou Wang, Yufei Zhou, Zhichao Liu, Shuguang Hu
Paper category : conference
Book title: International RILEM Conference on Volume Changes of Hardening Concrete: Testing and Mitigation
Editor(s): O. M. Jensen, P. Lura, K. Kovler
Print-ISBN: 2-35158-004-4
e-ISBN: 2351580052
Publisher: RILEM Publications SARL
Publication year: 2006
Pages: 51 - 55
Total Pages: 5
Nb references: 5
Language: English

Abstract: High strength and high performance concrete (HPC) have the characteristics of low Water/Binder ratio (W/B ratio) and high content of mineral admixtures, which improves the compactness and enhances the strength and durability of concrete, but also leads to some negative influences on curing due to the compact structure, and results in rapid decrease of internal relative humidity (IRH), greater autogenous shrinkage (AS) and cracking on early age. This paper analyzed the relationship between IRH and AS of low W/B ratio concrete, studied the effect of W/B ratio, types and amount of mineral admixtures, and amount of water introduced by lightweight aggregate on IRH and AS of low W/B ratio concrete. The results indicated that IRH and AS of concrete presented a linear relationship, AS could be reduced through the regulation of the decrease gradient of IRH. A lower W/B ratio and the addition of silica fume (SF) increased the decrease gradient of IRH on early age, while the introduction of fly ash (FA) could delay the decrease process of IRH. The introduction of pre-wetted lightweight aggregate could both delay the decrease gradient of IRH and reduce AS effectively. This effect would be enhanced with the increase of introduced water.

Online publication: 2006-07-30
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/2351580052.006