在冷解环境下研究缺陷的玄武岩纤维混凝土材料的动态断裂特性

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Updated: Jun 3, 2025

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Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior

Published on: June 27, 2018

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Guangzhao Pei¹, Dingjun Xiao¹, Miaomiao Zhang¹

¹Department of Mining Engineering, School of Environment and Resources, Southwest University of Science and Technology, Mianyang 621010, China.

Materials (Basel, Switzerland)

|January 8, 2025

概括

冷解周期降解了玄武岩纤维增强混凝土 (BFRC),增加了裂纹速度并降低了断裂性. 纤维特性,如长度和方向,显著影响抗裂能力,特别是在I模式断裂时.

科学领域:

材料科学材料科学材料科学
土木工程土木工程是指土木工程.
混凝土技术混凝土技术

背景情况:

混凝土结构容易受到环境因素的降解,例如结解周期 (FTC).
基岩纤维增强混凝土 (BFRC) 被探索为一种耐用替代品,但其在极端条件下的抗裂性需要彻底调查.

研究的目的:

为了评估BFRC的抗裂性能,BFRC受到了不同数量的FTC.
分析基岩纤维 (BF) 特性 (方向,位置,长度) 对应力强度因子的影响.
了解FTC和纤维增强对混凝土破裂行为的联合影响.

主要方法:

冲击压缩测试使用分离霍普金森压力杆 (SHPB) 装置以5米/秒的速度对暴露在0,10,20和30个FTC的BFRC标本进行了冲击压缩测试.
使用数值模拟来补充实验数据并分析压力强度因子.
研究了预制裂纹倾斜度 (0°,15°,28.89°) 和纤维参数对裂纹传播的影响.

主要成果:

增加FTC导致了更高的动态裂传播速度,并减少了不同裂倾向的模式I和模式II裂性.
对于0°裂纹倾斜,动态裂纹速度从311.84 m/s增加到449.92 m/s,I模式裂纹性从0.6266降至0.4902 MPa·m^0.5.
数字模拟表明,更接近,更长,更垂直于裂纹尖端的纤维显著降低了模式I压力强度因子,对模式II的影响最小.

结论:

FTCs显著损害了BFRC的裂抵抗力,表现为加速裂传播和减少断裂性.
玄武岩纤维的特性,特别是它们与裂纹尖端相对的近距离,长度和方向,在缓解裂纹传播方面发挥着至关重要的作用,特别是在I模式负载下.
该研究提供了对玄武岩纤维保护机制的定量见解,以防止混凝土中结解引起的损伤.

关键词:

盐纤维是一种基础纤维.混凝土混凝土混凝土是什么裂的传播速度是多少裂纹阻力裂纹阻力裂纹阻力动态断裂性坚性动态断裂性结解周期的周期

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