基于压电阻抗效应的套筒灌浆密实度识别试验研究

Experimental study on identification of sleeve grouting compactness based on piezoelectric impedance effect

采用压电阻抗技术对装配式混凝土结构钢筋连接套筒灌浆密实度的识别进行了试验研究。试验设计制作了单独套筒、套筒+素混凝土两组试件,并在单独套筒试件的套筒表面和套筒+素混凝土试件的混凝土表面布置压电片,采集压电片在不同灌浆工况下的电导信号。根据该信号频谱曲线的谐振频率和峰值变化对套筒灌浆密实度做出识别判断,并以套筒灌浆密实时信号为标准信号,采用均方根偏差作为识别套筒灌浆密实度的量化指标。试验结果表明,以套筒灌浆密实时电导曲线为基准,波峰处谐振频率向频率增大的方向偏移、电导峰值上升、电导均方根偏差增大能作为识别套筒灌浆不密实的有效指标。

Experiments on grouting compactness identification of rebar connecting sleeves for prefabricated concrete structures were carried out by using piezoelectric impedance technology.Two groups of individual sleeve specimens were designed and made,including individual sleeve group and sleeve + plain concrete group.The piezoelectric patches were arranged on the surface of individual sleeve specimens and the concrete suface of sleeve + plain concrete specimens to collect conductance signals of piezoelectric patches under different grouting conditions.According to the resonance frequency and peak value of the signal spectrum curve,the sleeve grouting compactness was identified and judged,and the sleeve grouting dense real-time signal was used as the standard signal,and the root mean square deviation was used as the quantitative index for identifying the sleeve grouting compactness.The experimental results show that,taking the conductance curve of sleeve grouting dense as the reference,the offset of resonant frequency of the peak in the direction of increasing frequency,the rise of conductance peak value and the increase of conductance root mean square deviation can be used as an effective indicator to identify the incomplete filling of the sleeve.