Volume deformation of steam-cured concrete with fly ash during and after steam curing. (1st November 2021)

• Record Type: Journal Article
• Authors: Wang, Penggang; Fu, Hua; Guo, Tengfei; Zuo, Wenqiang; Zhao, Haitao; Tian, Li; Chen, Chunlei
• Is Part Of: Construction & building materials. Volume 306(2021)
• Publication Date: 2021-11-01
• Subjects: Steam curing -- Fly ash -- Autogenous shrinkage -- Drying shrinkage -- Shrinkage model; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.124854
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The addition of fly ash can increase the development of shrinkage during steam curing. The hydration degree prediction development model of steam-cured cement paste is proposed. An integrated model of autogenous shrinkage and total shrinkage for concrete under steam curing conditions is proposed. Abstract: Steam-cured concrete presents high compressive strength at an early age. However, understanding regarding temperature-induced deformation development in steam–cured concrete with fly ash is limited. In the present research, the volume deformation of fly ash concrete experienced steam curing stage at an early age has been carried out. Volume deformation of concrete without fly ash is also studied as a comparison. In order to obtain the in situ property changes of steam-cured concrete, a strain-temperature-humidity integrated acquisition system was used to continuously record the interior strain, temperature, and humidity evolutions of the sample. The test results show that the autogenous shrinkage occurs at the constant temperature stage of steam curing, and the shrinkage after steam curing is mainly because of the drying effect. The addition of fly ash can increase the development of shrinkage in steam curing, but it is beneficial to shrinkage after steam curing. And the hydration degree prediction development model of steam-cured cement paste is proposed. Finally, a micromechanical model is proposed based on the capillary tension produced by pores, using interior humidity and hydration degree as the driving parameters, which decently predicts the total shrinkage and autogenous shrinkage of concrete specimens after steam curing.