Feasibility Study on Grouting Compactness Detection in Sleeves Using Piezoelectric Transducers

Abstract

Steel sleeve grouting connections are widely used in prefabricated concrete structures. It is well known that insufficient grouting increases the chance of structural failure. As such, it is critical to monitor the density and compactness of grouting sleeve during the construction process, which however remains significant challenges as it is deeply buried in the beam and column. In this study, a lead zirconate titanate (PZT)-based sleeve grouting compactness detection method was systematically investigated. Five grouting sleeves samples with different degrees of compactness were prepared and four PZT transducers were surface-bonded on opposite sides of the outer wall of each sleeve. Two acts as actuators to generate stress wave signals, and the other two operate as sensors to receive the signals. The wavelet packet energy and Hilbert–Huang transform methods were applied to process the stress wave signals, and with the chosen characteristic parameters, the correction model of the grouting compactness was established. Experimental results show that the wavelet packet total energy values and the Hilbert energy peak values are related to the grouting compactness, indicating the feasibility of using PZT sensors to detect the compactness of grouting sleeves.