实验研究和数值模拟不同纤维类型对喷混凝土基本机械性能的影响
Cheng-Yong Liu1, Han-Qiu Wang1, Xue-Feng Liu2
1China Coal Energy Research Institute Co., Ltd, Xi'an, 710001, Shaanxi, China.
Scientific reports
|November 4, 2024
概括
钢,玻璃和聚烯纤维显著增强了混凝土的性能.
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:
- 纤维增强混凝土 (FRC) 对于提高材料性能至关重要.
- 冲击混凝土的应用要求优化混凝土的性能,以保持结构完整.
- 了解纤维矩阵相互作用是增强混凝土机械学的关键.
研究的目的:
- 研究钢,玻璃和聚烯纤维对混凝土机械性能的增强效应.
- 为了确定最佳的纤维类型和剂量,用于射击混凝土应用.
- 阐明纤维增强混凝土性能背后的机制.
主要方法:
- 实验室测试混凝土的屈曲和压力强度,使用不同的纤维剂量.
- 使用ABAQUS进行数值模拟,用于微观分析纤维-矩阵相互作用.
- 实地实验应用优化的纤维剂量在一个矿山的湿 shotcrete 支持系统.
主要成果:
- 最佳剂量 (2.0%的钢,1.5%的玻璃,2.0%的聚烯) 显著增加了屈曲强度 (高达138.6%).
- 聚烯纤维显示压力强度增强最显著 (18.3%),达到2.0%.
- 数字模拟证实了纤维通过增强元素连接和减少应力度来改善混凝土的机械性能.
结论:
- 建议使用2.0%的聚烯纤维用于射击混凝土,这是由于其优越的屈曲强度和减少的聚合.
- 优化的纤维剂量有效地控制了矿山湿应用中的道变形.
- 该研究为选择和应用在喷混凝土项目中的纤维提供了实际指导.
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