期刊论文

Simulation Experiment on Rock Bolt Defect and EMD Analysis on Features of Its Ultrasonic Testing Signals

中文

公路交通科技

1002-0268

2019

36

10

91-97

10.3969/j.issn.1002-0268.2019.010.012

国家自然科学基金项目(51678071) 国家自然科学基金青年基金项目(51608183).

本校为其他机构

为准确识别锚杆缺陷位置,了解超声波在锚杆中的传播机理和能量分布特征,对试验模型中的模拟锚杆进行超声波检测,基于EMD方法对检测信号进行能量分布特征分析。通过在沙槽中埋设钢筋来模拟锚杆,分别设置完整光圆钢筋、截断光圆钢筋、完整螺纹钢筋和截断螺纹钢筋4种。测试中超声波成像方法为A型,脉冲形状为全检波形,应用希尔伯特-黄变换的核心方法EMD分解法对原始信号进行时频局部化处理。结果表明,超声波法可以确定不同直径的锚杆长度及缺陷位置,解决了动测法只能对这些参数作定性评价的问题; EMD方法能根据超声波检测信号本身固有的特性进行自适应分解,前几阶IMF分量包含锚杆长度及缺陷位置的主...

In order to identify the defect in rock bolt accurately, and understand the ultrasonic wave transmission mechanism and energy distribution characteristic in rock bolt, the simulation rock bolt in the experimental model is detected by UT method, and the UT signal energy distribution characteristics are analysed based on EMD method. In the experiment, the bolt is simulated by embedding rebars in sand, including intact round rebar, truncated round rebar, intact thread rebar and truncated thread rebar. The ultrasonic imaging method is A type with pulse shape full detection. Moreover, the EMD decom...