{"title":"高温对纤维增强水泥基复合材料微观结构和力学性能的影响","authors":"Chen Ge, Xiaoliang Chen, Yongfan Gong, Xijun Kong, Fei Chen","doi":"10.3390/cryst14090778","DOIUrl":null,"url":null,"abstract":"Synthetic fibers can effectively inhibit the formation and propagation of micro-cracks in concrete, significantly reducing the number and scale of cracks within the concrete matrix, thereby enhancing the concrete’s crack resistance and seepage prevention capabilities. In this study, two types of synthetic fibers, polyvinyl alcohol (PVA) and polypropylene (PP), were incorporated into cement mortar to investigate their microstructural evolution at elevated temperatures and their influence on the mechanical properties of the mortar. Both fibers were added at a volume content of 0.5%. The mortar samples were subjected to the following temperature conditions: 20 °C (ambient), 200 °C, 400 °C, and 500 °C. The results indicate that the synthetic fibers employed in this study improved the tensile properties of the mortar at room temperature (20 °C). This enhancement persisted up to 400 °C, beyond which, at 500 °C, the mechanical properties of the fiber-reinforced mortar deteriorated significantly. At 400 °C, the tensile strength of the PVA group increased by approximately 16% compared to the unblended fiber group (JZ) and by about 45% compared to the PP group. After treatment at 500 °C, the tensile strength of mortar specimens in the PVA group and the PP group decreased by 36.47% and 24.14%, respectively, compared with that at 20 °C. The porous structure formed due to the high-temperature ablation of the synthetic fibers contributed to relieving the internal pressure within the mortar.","PeriodicalId":10855,"journal":{"name":"Crystals","volume":"8 1","pages":""},"PeriodicalIF":2.4000,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Effect of High Temperature on Micro-Structure and Mechanical Properties of Fiber-Reinforced Cement-Based Composites\",\"authors\":\"Chen Ge, Xiaoliang Chen, Yongfan Gong, Xijun Kong, Fei Chen\",\"doi\":\"10.3390/cryst14090778\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Synthetic fibers can effectively inhibit the formation and propagation of micro-cracks in concrete, significantly reducing the number and scale of cracks within the concrete matrix, thereby enhancing the concrete’s crack resistance and seepage prevention capabilities. In this study, two types of synthetic fibers, polyvinyl alcohol (PVA) and polypropylene (PP), were incorporated into cement mortar to investigate their microstructural evolution at elevated temperatures and their influence on the mechanical properties of the mortar. Both fibers were added at a volume content of 0.5%. The mortar samples were subjected to the following temperature conditions: 20 °C (ambient), 200 °C, 400 °C, and 500 °C. The results indicate that the synthetic fibers employed in this study improved the tensile properties of the mortar at room temperature (20 °C). This enhancement persisted up to 400 °C, beyond which, at 500 °C, the mechanical properties of the fiber-reinforced mortar deteriorated significantly. At 400 °C, the tensile strength of the PVA group increased by approximately 16% compared to the unblended fiber group (JZ) and by about 45% compared to the PP group. After treatment at 500 °C, the tensile strength of mortar specimens in the PVA group and the PP group decreased by 36.47% and 24.14%, respectively, compared with that at 20 °C. The porous structure formed due to the high-temperature ablation of the synthetic fibers contributed to relieving the internal pressure within the mortar.\",\"PeriodicalId\":10855,\"journal\":{\"name\":\"Crystals\",\"volume\":\"8 1\",\"pages\":\"\"},\"PeriodicalIF\":2.4000,\"publicationDate\":\"2024-08-31\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Crystals\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://doi.org/10.3390/cryst14090778\",\"RegionNum\":4,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CRYSTALLOGRAPHY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Crystals","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.3390/cryst14090778","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CRYSTALLOGRAPHY","Score":null,"Total":0}
引用次数: 0
摘要
合成纤维可有效抑制混凝土中微裂缝的形成和扩展,显著减少混凝土基体中裂缝的数量和规模,从而提高混凝土的抗裂性和防渗能力。本研究在水泥砂浆中加入了聚乙烯醇(PVA)和聚丙烯(PP)两种合成纤维,以研究它们在高温下的微观结构演变及其对砂浆机械性能的影响。两种纤维的添加量均为 0.5%。砂浆样品经受了以下温度条件的考验:20°C(环境温度)、200°C、400°C 和 500°C。结果表明,本研究中使用的合成纤维改善了砂浆在室温(20 °C)下的拉伸性能。这种改善一直持续到 400 °C,当温度超过 500 °C时,纤维增强砂浆的机械性能显著下降。400 °C 时,PVA 组的拉伸强度比未掺入纤维组(JZ)提高了约 16%,比 PP 组提高了约 45%。经过 500 °C 处理后,PVA 组和 PP 组砂浆试样的抗拉强度分别比 20 °C 时降低了 36.47% 和 24.14%。合成纤维高温烧蚀形成的多孔结构有助于缓解砂浆内部的压力。
Effect of High Temperature on Micro-Structure and Mechanical Properties of Fiber-Reinforced Cement-Based Composites
Synthetic fibers can effectively inhibit the formation and propagation of micro-cracks in concrete, significantly reducing the number and scale of cracks within the concrete matrix, thereby enhancing the concrete’s crack resistance and seepage prevention capabilities. In this study, two types of synthetic fibers, polyvinyl alcohol (PVA) and polypropylene (PP), were incorporated into cement mortar to investigate their microstructural evolution at elevated temperatures and their influence on the mechanical properties of the mortar. Both fibers were added at a volume content of 0.5%. The mortar samples were subjected to the following temperature conditions: 20 °C (ambient), 200 °C, 400 °C, and 500 °C. The results indicate that the synthetic fibers employed in this study improved the tensile properties of the mortar at room temperature (20 °C). This enhancement persisted up to 400 °C, beyond which, at 500 °C, the mechanical properties of the fiber-reinforced mortar deteriorated significantly. At 400 °C, the tensile strength of the PVA group increased by approximately 16% compared to the unblended fiber group (JZ) and by about 45% compared to the PP group. After treatment at 500 °C, the tensile strength of mortar specimens in the PVA group and the PP group decreased by 36.47% and 24.14%, respectively, compared with that at 20 °C. The porous structure formed due to the high-temperature ablation of the synthetic fibers contributed to relieving the internal pressure within the mortar.
期刊介绍:
Crystals (ISSN 2073-4352) is an open access journal that covers all aspects of crystalline material research. Crystals can act as a reference, and as a publication resource, to the community. It publishes reviews, regular research articles, and short communications. Our aim is to encourage scientists to publish their experimental and theoretical results in as much detail as possible. Therefore, there is no restriction on article length. Full experimental details must be provided to enable the results to be reproduced. Crystals provides a forum for the advancement of our understanding of the nucleation, growth, processing, and characterization of crystalline materials. Their mechanical, chemical, electronic, magnetic, and optical properties, and their diverse applications, are all considered to be of importance.