Effect of n-C-S-H-PCE and slag powder on the autogenous shrinkage of high-strength steam-free pipe pile concrete. (28th March 2022)

• Record Type: Journal Article
• Authors: Wang, Penggang; Fu, Hua; Zuo, Wenqiang; Luo, Shuqiong; Zhao, Haitao; Feng, Pan; Wang, Hui
• Is Part Of: Construction & building materials. Volume 325(2022)
• Publication Date: 2022-03-28
• Subjects: PHC pipe pile -- Autogenous Shrinkage -- Shrinkage Model -- n-C-S-H-PCE -- Slag powder; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2022.126815
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The effect of n-C-S-H-PCE on the strength, hydration degree, capillary pressure, and autogenous shrinkage of steam-free concrete was studied. A model suitable for predicting the autogenous shrinkage of high-strength concrete, such as PHC pipe piles, was established. The deformation mechanisms of high-strength concrete containing n-C-S-H-PCE and slag powders were analyzed. Abstract: This study investigates the effect of the calcium silicate hydrate–Polycarboxylate ether nanocomposite (n-C-S-H-PCE) on the development of autogenous shrinkage and other relevant properties, including strength, hydration degree, elastic modulus, and capillary pressure. To measure the autogenous shrinkage development of concrete, a strain-temperature-humidity integrated acquisition system was used to continuously monitor the interior strain, temperature, and humidity evolutions of the concrete. The results show that the n-C-S-H-PCE has a pronounced enhancement effect on the mechanical properties up to 7 d. The early strength enhancement of the n-C-S-H-PCE can reach 64% at 1 d. Due to the fast hydration, the autogenous shrinkage is higher in the concrete containing n-C-S-H-PCE. And the slag powder also increases the autogenous shrinkage. Moreover, a model suitable for predicting the autogenous shrinkage of high-strength concrete, such as PHC pipe piles, is established. The prediction values are in good agreement with the experimental values. We finally conclude that the n-C-S-H-PCE increases the hydration degree, which results in a lower internal RH and a higher capillary pressure at the early hydration period compared with the reference concrete. This study provides a reference for the application of n-C-S-H-PCE and slag powder in concrete and the further prediction of the autogenous shrinkage for concrete containing those ingredients.