Title:
Enhanced Internal Curing for Ultra-High-Performance Concrete Using Reactive Curing Solution
Author(s):
Weibo Tan, Peiyuan Chen, Ying Xu, Chunning Pei, Yi Fang, Jin Li, Xin Qian, and Jialai Wang
Publication:
Materials Journal
Volume:
123
Issue:
3
Appears on pages(s):
135-148
Keywords:
autogenous shrinkage; internal curing; internal relative humidity; ultra-high-performance concrete (UHPC); urea solution
DOI:
10.14359/51749446
Date:
5/1/2026
Abstract:
To address the autogenous shrinkage issue of ultra-high-performance concrete (UHPC), internal curing technology has shown great potential in resolving this challenge by providing additional moisture. To further improve its curing efficiency, this study proposes an innovative internal curing technology that can significantly reduce autogenous shrinkage without increasing the amount of internal curing water or compromising mechanical strength. This approach uses perforated cenospheres (PCs) as internal curing agents while substituting internal curing water with urea solution. In addition to replenishing water, urea solution, once released into the cement paste, can react with portlandite. This reaction generates CaCO3; owing to the intrinsic properties of CaCO3, it has a larger macroscopic volume and a much higher elastic modulus than portlandite. This approach effectively reduces chemical shrinkage while concurrently increasing the stiffness of the cement paste, thereby achieving a significant reduction in autogenous shrinkage. As a result, replacing water with 3% urea solution in PCs reduces autogenous shrinkage of UHPC from over 90% to less than 50%.
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