Multiscale analysis on microstructural changes in hardened cement paste dried under different relative humidity levels: A comparison with cement paste containing water-dispersible polyurethane ether compound
IF 10.9 1区 工程技术Q1 CONSTRUCTION & BUILDING TECHNOLOGY
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引用次数: 0
Abstract
This study investigated microstructural changes in hardened cement paste with and without a water-dispersible polyurethane (PU) ether compound under varying relative humidity (RH) levels. The small-angle X-ray scattering technique was used to analyse the agglomeration, piling, and densification of calcium silicate hydrate (C-S-H) units. Mercury intrusion porosimetry and water vapour sorption isotherms were used to further characterise pore structures and surface areas, focusing on the C-S-H unit changes across different RH levels and the influence of PU. The presence of PU reduced variation in scattering profiles and subsequent calculated disc thickness at each RH, indicating the inhibition of C-S-H structural evolution during drying. These findings indicate less variation in the pore structure and surface area during the drying process than in the paste without PU. The length change isotherm of the cement paste with PU confirmed reduced shrinkage and hysteresis, which can be attributed to microstructural stabilisation.
期刊介绍:
Cement and Concrete Research is dedicated to publishing top-notch research on the materials science and engineering of cement, cement composites, mortars, concrete, and related materials incorporating cement or other mineral binders. The journal prioritizes reporting significant findings in research on the properties and performance of cementitious materials. It also covers novel experimental techniques, the latest analytical and modeling methods, examination and diagnosis of actual cement and concrete structures, and the exploration of potential improvements in materials.