| 摘要: |
| 在用超声波检测混凝土裂缝深度的试验中，曾发现因换能器平置裂缝两侧的间距不同引起超声波首波相位变化的规律.基于超声波检测混凝土裂缝深度试验因裂缝中有水的特殊性，当2个换能器间距小于2.0倍裂缝深度时，并未观察到超声波首波相位反转现象，由此提出了超声波首波相位反转机理的新解析，即超声波首波相位反转是由于折射横波在裂缝附近先于折射纵波到达接收换能器所致. |
| 关键词: 超声波 检测 混凝土 裂缝深度 首波相位反转 横波 |
| DOI：103969/j.issn1007 9629201604012 |
| 分类号: |
| 基金项目: |
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| Explanation of the Mechanism of Ultrasonic First Pulse Phase Reverse |
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TONG Nian1, TONG Shouxing2
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1.School of Foreign Language, Jianqiao University, Shanghai 201306, China;2.School of Materials Science and Engineering, Tongji University, Shanghai 201804, China
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| Abstract: |
| In the experiments of the crack depth testing of concrete by ultrasonic method, the rule of ultrasonic first pulse phase reverse had been discovered when the distances between the two transducers which were placed on the two sides of the crack were changed. Based on the special conditions in which the crack was filled by water during the experiments of the crack depth testing of concrete by ultrasonic method, when the distance between the two transducers is less than twice of crack depth, the phenomenon of ultrasonic first pulse phase reverse could not be found. Thus, new explanation of the mechanism of ultrasonic first pulse phase reverse is proposed. The ultrasonic first pulse phase reverse is due to the fact that the refracting transversal wave arrives to the receiver transducer faster than that of the refracting longitudinal wave. |
| Key words: ultrasonic testing concrete crack depth first pulse phase reverse transversal wave |
