对估计模块的砂样本的方法进行比较
Simon Schmid1, Jithender J Timothy2, Elena Woydich2
1Department of Materials Engineering, TUM School of Engineering and Design, Technical University of Munich, Franz-Langinger-Str. 10, Munich, 81245, Bavaria, Germany. sim.schmid@tum.de.
Scientific reports
|June 20, 2024
概括
估计水泥材料的特性,如的模量对于结构完整性至关重要. 全波形逆转和计算机断层扫描为预测静态模量提供了比手动超声波分析更准确,更少变量的非破坏性方法.
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
- 非破坏性测试是指非破坏性测试.
背景情况:
- 对基于水泥的材料的材料参数的准确估计对于评估结构完整性至关重要.
- 破坏性方法 (压缩试验) 和非破坏性方法 (超声波,计算机断层扫描) 都用于确定模量.
- 超声波提供动态的模量,需要使用基于文献的公式将其转换为静态的模量.
研究的目的:
- 为了比较不同非破坏性方法的准确性和可靠性,用于估计砂样本中的模量.
- 评估用于超声波信号分析的手动开始选择和全波形逆转 (FWI) 技术.
- 根据材料分布,使用计算机断层扫描 (CT) 确定扬模块.
主要方法:
- 测试了具有不同砂与水泥比率 (20-65%) 的圆柱形砂样本.
- 超声波信号使用手动发病选和FWI进行分析.
- FWI涉及在数值模型中代调整超声速以匹配测量信号.
- 的模块从CT扫描中通过将图像细分为沙子,水泥和毛孔进行半分析确定.
主要成果:
- 与手动开始采摘相比,FWI提供了对Young的模块的更好的估计,最佳RMSE为0.34 GPa与0.87 GPa.
- 与手动采摘相比,FWI的材料参数偏差较低 (最大std dev 0.36),而不是手动采摘 (最大std dev 1.11).
- 来自CT的Young模块与压缩试验结果非常相匹配,达到0.13GPa的RMSE.
结论:
- 全波形反转是一种比手动开始选更准确和可靠的非破坏性方法来估计基于水泥的材料中的模量.
- 计算机断层扫描提供高度准确的模值估计,与破坏性压缩试验密切相关.
- 这些先进的非破坏性技术对于精确的结构完整性评估至关重要.
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