混凝土动态弹性模块的数值建模
Gustavo de Miranda Saleme Gidrão1, Ricardo Carrazedo2, Rúbia Mara Bosse1
1Department of Civil Engineering, Federal University of Technology-Paraná (UTFPR), Guarapuava 85053-525, PR, Brazil.
Materials (Basel, Switzerland)
|June 10, 2023
概括
本研究模拟材料特性,以评估它们对动态弹性模量的影响. 数字和声学测试验证了这些发现,揭示了模型精度的变化与材料组成和水-水泥比率.
科学领域:
- 材料科学 材料科学 材料科学
- 计算力学 计算力学 计算力学
- 土木工程 土木工程是指土木工程.
背景情况:
- 经典的同质化模型经常用于预测复合材料的动态弹性模量.
- 了解体积分数,相性质和过渡区的影响对于准确的材料表征至关重要.
- 混凝土和砂的行为,特别是在不同的水-水泥比率下,需要详细的研究.
研究的目的:
- 用模拟来评估关键参数 (体积分数,弹性性质,过渡区) 对有效动态弹性模量的影响.
- 评估经典同质化模型在预测动态弹性模量方面的准确性.
- 通过实验声学测试验证数值模拟,并确定混凝土和砂的弹性模量.
主要方法:
- 使用有限元法 (FEM) 的数值模拟来评估自然频率及其与动态弹性模量 (Ed) 的相关性.
- 开发频率方程,以将自然频率与编辑联系起来.
- 实验验证使用声学测试对不同水-水泥比率的混凝土和砂样本进行实验验证 (w/c = 0.3,0.5,0.7).
主要成果:
- FEM模拟提供了对材料参数对动态弹性模量影响的见解.
- 用数值模拟 (x = 0.27) 校准的希尔什模型显示,对于 w/c = 0.3 和 0.5.5 的混凝土,准确度很好 (误差为5%).
- 在 w/c = 0.7 时,Young 的模量与 Reuss 模型相似,类似于模拟的三相材料,表明某些组成的局限性.
- 发现哈辛-施特里克曼极限在动态条件下对理论双相材料不完全适用.
结论:
- 数字模拟对于评估材料参数对动态弹性模量的影响是有效的.
- 同质化模型的准确性取决于材料成分和特定条件.
- 实验验证对于证实材料科学和土木工程应用中的数值预测的可靠性至关重要.
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