Flexural post-cracking performance of macro synthetic fiber reinforced super workable concrete influenced by shrinkage-reducing admixture

IF 10.8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement & concrete composites Pub Date : 2024-11-13 DOI:10.1016/j.cemconcomp.2024.105847

Jingjie Wei , Nima Farzadnia , Kamal H. Khayat

{"title":"Flexural post-cracking performance of macro synthetic fiber reinforced super workable concrete influenced by shrinkage-reducing admixture","authors":"Jingjie Wei , Nima Farzadnia , Kamal H. Khayat","doi":"10.1016/j.cemconcomp.2024.105847","DOIUrl":null,"url":null,"abstract":"<div><div>Most literature has focused on the effect of shrinkage-reducing admixture (SRA) in shrinkage mitigation resistance of concrete. This study aims to examine the impact of SRA on the efficiency of macro synthetic fibers (MSF) in enhancing the flexural post-cracking behavior of fiber-reinforced super workable concrete (FR-SWC). A comparative analysis of the influence of fiber combinations on the flexural post-cracking behavior of beams is also included. Results showed that a higher dosage of SRA, particularly at 5 % by mass of binder, had a noticeable negative impact on flexural post-cracking performance of beams while exhibiting positive effect on workability and shrinkage reduction. However, incorporating low dosages of SRA (1.25 % by mass of binder) did not have a significant impact on the ability of MSF. This was attributed to the reduction of the MSF-matrix bond strength caused by a significant delay in cement hydration. The characteristics of selected MSF type, including length and surface roughness had a positive effect on the post-cracking performance of FR-SWC, regardless of SRA dosage. The notched beams made with 100 % MSF<sub>A</sub> outperformed those made with fiber combination of 25 % MSFA and 75 % MSF<sub>B</sub>. Beams made with 100 % MSF<sub>A</sub> showed 55 % higher residual flexural tensile strength, 49 % higher equivalent flexural tensile strength, 50 % higher fracture energy, and 35 % higher equivalent flexural strength ratio compared to beams made with fiber combination of 25 % MSF<sub>A</sub> and 75 % MSF<sub>B</sub>. Therefore, the negative effect of SRA on the flexural-post cracking behavior can be partial compensated by adjusting MSF content and combinations.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"155 ","pages":"Article 105847"},"PeriodicalIF":10.8000,"publicationDate":"2024-11-13","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/S0958946524004207","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

Most literature has focused on the effect of shrinkage-reducing admixture (SRA) in shrinkage mitigation resistance of concrete. This study aims to examine the impact of SRA on the efficiency of macro synthetic fibers (MSF) in enhancing the flexural post-cracking behavior of fiber-reinforced super workable concrete (FR-SWC). A comparative analysis of the influence of fiber combinations on the flexural post-cracking behavior of beams is also included. Results showed that a higher dosage of SRA, particularly at 5 % by mass of binder, had a noticeable negative impact on flexural post-cracking performance of beams while exhibiting positive effect on workability and shrinkage reduction. However, incorporating low dosages of SRA (1.25 % by mass of binder) did not have a significant impact on the ability of MSF. This was attributed to the reduction of the MSF-matrix bond strength caused by a significant delay in cement hydration. The characteristics of selected MSF type, including length and surface roughness had a positive effect on the post-cracking performance of FR-SWC, regardless of SRA dosage. The notched beams made with 100 % MSF_A outperformed those made with fiber combination of 25 % MSFA and 75 % MSF_B. Beams made with 100 % MSF_A showed 55 % higher residual flexural tensile strength, 49 % higher equivalent flexural tensile strength, 50 % higher fracture energy, and 35 % higher equivalent flexural strength ratio compared to beams made with fiber combination of 25 % MSF_A and 75 % MSF_B. Therefore, the negative effect of SRA on the flexural-post cracking behavior can be partial compensated by adjusting MSF content and combinations.

查看原文本刊更多论文

受减缩外加剂影响的大体积合成纤维增强超强可加工混凝土的挠曲后开裂性能

大多数文献都关注减缩外加剂（SRA）对混凝土抗收缩性的影响。本研究旨在考察 SRA 对大型合成纤维（MSF）在增强纤维增强超强工作性混凝土（FR-SWC）抗弯后开裂行为方面效率的影响。此外，还比较分析了纤维组合对梁弯曲后开裂行为的影响。结果表明，较高的 SRA 用量（尤其是粘结剂质量的 5%）对梁的挠曲开裂后性能有明显的负面影响，同时对工作性和收缩减少有积极作用。然而，添加低剂量的 SRA（粘结剂质量的 1.25%）对 MSF 的能力没有显著影响。这是因为水泥水化明显延迟导致 MSF-基质粘结强度降低。所选 MSF 类型的特征（包括长度和表面粗糙度）对 FR-SWC 的开裂后性能有积极影响，与 SRA 用量无关。使用 100% MSFA 制作的凹槽梁优于使用 25% MSFA 和 75% MSFB 纤维组合制作的凹槽梁。与使用 25% MSFA 和 75% MSFB 纤维组合制成的梁相比，使用 100% MSFA 制成的梁的残余抗弯强度提高了 55%，等效抗弯强度提高了 49%，断裂能提高了 50%，等效抗弯强度比提高了 35%。因此，通过调整 MSF 的含量和组合，可以部分弥补 SRA 对抗弯后开裂行为的负面影响。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Cement & concrete composites 工程技术-材料科学：复合

CiteScore

18.70

自引率

11.40%

发文量

459

审稿时长

65 days

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.