对混凝土的不同粘土添加剂对其超声波声学参数和压力强度的影响
Wenxiang Wu1,2,3, Shunchao Chen4, Yong Wu5,6,7
1School of Civil Engineering, Southwest Forestry University, Kunming, Yunnan, 650224, China.
Scientific reports
|January 22, 2025
概括
更高的混凝土泥含量降低了压力强度,并改变了超声波声学参数. 本研究量化了这些影响,为评估具体质量和缺陷提供了参考.
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 不破坏性测试
背景情况:
- 混凝土的质量对结构完整性至关重要.
- 混凝土中的泥污染可能会对其机械性能和耐用性产生负面影响.
- 超声波声学参数为非破坏性评估混凝土质量提供了一个潜在的方法.
研究的目的:
- 研究混凝土泥含量对超声波声学参数和压力强度的影响.
- 导出和验证泥含量和声学参数/强度之间的关系方程.
- 为评估由泥含量引起的混凝土缺陷提供参考.
主要方法:
- 理论推导泥含量,声学参数和压力强度之间的关系.
- 对具有不同泥含量的混凝土样本进行实验测试.
- 分析超声波速度,声音时间,振幅和频率.
主要成果:
- 增加的泥含量与压力强度,声音速度和振幅的降低以及声音时间和频率的增加 (在更高的百分比下) 相对相关.
- 确定了泥含量的特定值 (例如,对于速度/时间的显著变化>10%,对于频率>20%).
- 在泥含量和压力强度 (R2=0.97),振幅 (R2=0.91) 和频率 (R2=0.95) 之间观察到非线性关系.
结论:
- 泥含量显著降低了混凝土的压力强度,并改变了其超声波声学特性.
- 超声波参数可以有效地表明混凝土中泥污染的存在和程度.
- 由此得出的关系方程为基于泥含量评估混凝土质量提供了定量基础.
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