钢纤维增强混凝土的计算断裂进化分析,使用混凝土持续损伤和纤维渐进模型
Iwona Pokorska1,2, Mariusz Poński1, Wojciech Kubissa3
1Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warszawa, Poland.
Materials (Basel, Switzerland)
|August 26, 2023
概括
这项研究研究了使用断裂力学进行钢纤维增强混凝土 (SFRC) 破裂. 实验和数值分析表明,准静态方法是合适的,但动态效应仍然难以准确地建模.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 材料机械学 材料机械学
背景情况:
- 由于水分流失而引起的混凝土裂是一个普遍的问题.
- 断裂力学为理解混凝土的断裂行为提供了一个框架.
- 钢纤维增强混凝土 (SFRC) 提供了增强的机械性能.
研究的目的:
- 通过实验和数值分析SFRC的断裂行为.
- 为了研究曲下的力 (F) - 裂口开口位移 (CMOD) 曲线.
- 评估SFRC断裂分析准静态数值方法的适用性.
主要方法:
- 在带有隙的SFRC样本上进行了三点曲试验.
- 使用非标准的样本尺寸来捕捉快速的F-CMOD曲线变化.
- 对关键材料参数进行了概率分析.
主要成果:
- 准静态数值方法可以为SFRC断裂分析提供合适的结果.
- 实验F-CMOD曲线显示了显著的动态效应.
- 关键的材料特性,如峰值强度和断裂能量被概率分析.
结论:
- 准静态数值模拟对于分析SFRC断裂是可行的.
- 在SFRC中准确地建模动态效应仍然是一个挑战.
- 了解裂能量和材料特性对于SFRC应用至关重要.
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