{"title":"Influence of water-soluble leachates from natural fibers on the hydration and microstructure of cement paste studied by nuclear magnetic resonance","authors":"XiaoXiao Zhang , Leo Pel , David Smeulders","doi":"10.1016/j.cemconres.2024.107629","DOIUrl":null,"url":null,"abstract":"<div><p>This study aims to evaluate the influence of natural fiber leachates on cement pastes for advanced bio-composite production. Cement samples are made by mixing cement with leachates from oil palm and coir fibers at three concentrations. Through Nuclear Magnetic Resonance T<sub>1</sub>-T<sub>2</sub> relaxations, fresh cement samples are evaluated for hydration reaction and microstructure. Results show that oil palm fiber leachates prolong plateaus in T<sub>1</sub> and T<sub>2</sub>, suggesting a retarding effect on cement hydration. Subsequently, increased T<sub>1</sub> values and an extra T<sub>2</sub> component are observed which suggest coarser pores. Additionally, the leachates increase water fractions, reflecting reduced cement hydration degree. With increasing leachate concentration, the retarding effect and extra larger pores become apparent. Conversely, coir fiber leachates exhibit negligible influence. This difference is attributed to the less saccharides. These saccharides function through simultaneous adsorption, nucleation, complexation and precipitation. In conclusion, coir fibers demonstrate better compatibility with cement than oil palm concerning leachates.</p></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"185 ","pages":"Article 107629"},"PeriodicalIF":10.9000,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0008884624002102/pdfft?md5=de3a5e6ec4709faf7c8c0f2ab1522cad&pid=1-s2.0-S0008884624002102-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement and Concrete Research","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0008884624002102","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
This study aims to evaluate the influence of natural fiber leachates on cement pastes for advanced bio-composite production. Cement samples are made by mixing cement with leachates from oil palm and coir fibers at three concentrations. Through Nuclear Magnetic Resonance T1-T2 relaxations, fresh cement samples are evaluated for hydration reaction and microstructure. Results show that oil palm fiber leachates prolong plateaus in T1 and T2, suggesting a retarding effect on cement hydration. Subsequently, increased T1 values and an extra T2 component are observed which suggest coarser pores. Additionally, the leachates increase water fractions, reflecting reduced cement hydration degree. With increasing leachate concentration, the retarding effect and extra larger pores become apparent. Conversely, coir fiber leachates exhibit negligible influence. This difference is attributed to the less saccharides. These saccharides function through simultaneous adsorption, nucleation, complexation and precipitation. In conclusion, coir fibers demonstrate better compatibility with cement than oil palm concerning leachates.
本研究旨在评估天然纤维沥滤液对用于先进生物复合材料生产的水泥浆的影响。将水泥与三种浓度的油棕纤维和椰壳纤维浸出物混合制成水泥样品。通过核磁共振 T-T 弛豫,对新鲜水泥样品的水化反应和微观结构进行了评估。结果表明,油棕纤维浸出物延长了 T 值和 T 值的高原期,表明对水泥水化有延缓作用。随后,观察到 T 值增大,T 分量增加,表明孔隙变粗。此外,浸出液增加了水分量,反映出水泥水化程度降低。随着浸出液浓度的增加,延缓效应和额外的较大孔隙变得明显。相反,椰壳纤维沥滤液的影响可以忽略不计。这种差异归因于较少的糖类物质。这些糖通过同时吸附、成核、复合和沉淀发挥作用。总之,与油棕浸出物相比,椰壳纤维与水泥的相容性更好。
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.