{"title":"Time-dependent rheological behavior of hydrating cement paste containing calcium carbonate whiskers","authors":"Wen Si , Xing Ming , Mingli Cao","doi":"10.1016/j.cemconcomp.2024.105775","DOIUrl":null,"url":null,"abstract":"<div><div>In this research, the action mechanism of aragonite calcium carbonate whiskers (CW) on the time-dependent rheological performance during early cement paste hydration are examined by combining rheometer, calorimetry, thermogravimetry (TG/DTG), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and free water content test. Regarding time-dependent rheological properties, it is found that CW can improve the rheological parameters of cement paste and converse the fluidity behavior by means of morphological and chemical effects. Free water content and FT-IR results indicate that CW can absorb free water to retard rheological properties loss. In terms of early hydration of cement paste, new hydration products are generated due to the chemical effects of CW, which can be verified by XRD, DTG and energy-dispersive X-ray spectroscopy (EDS). And the increase in content of ettringite, Ca(OH)<sub>2</sub> and gel/space ratio induced by participation of CW can also be distinctly observed. After discussing the time-dependent rheological parameters and hydration characteristic parameters, it has been clarified that the primary factor contributing to the increase in time-dependent rheological parameters is the reduction in free water content. However, the incorporation of CW intensifies the cement hydration process, leading to the predominant influence of hydrated phase contents and particle size on the system.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"154 ","pages":"Article 105775"},"PeriodicalIF":10.8000,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement & concrete composites","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0958946524003482","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
In this research, the action mechanism of aragonite calcium carbonate whiskers (CW) on the time-dependent rheological performance during early cement paste hydration are examined by combining rheometer, calorimetry, thermogravimetry (TG/DTG), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and free water content test. Regarding time-dependent rheological properties, it is found that CW can improve the rheological parameters of cement paste and converse the fluidity behavior by means of morphological and chemical effects. Free water content and FT-IR results indicate that CW can absorb free water to retard rheological properties loss. In terms of early hydration of cement paste, new hydration products are generated due to the chemical effects of CW, which can be verified by XRD, DTG and energy-dispersive X-ray spectroscopy (EDS). And the increase in content of ettringite, Ca(OH)2 and gel/space ratio induced by participation of CW can also be distinctly observed. After discussing the time-dependent rheological parameters and hydration characteristic parameters, it has been clarified that the primary factor contributing to the increase in time-dependent rheological parameters is the reduction in free water content. However, the incorporation of CW intensifies the cement hydration process, leading to the predominant influence of hydrated phase contents and particle size on the system.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.