Quantitative health monitoring of bolted joints using a piezoceramic actuator–sensor

Abstract

The non-destructive evaluation technique using a piezoceramic (PZT) as an actuator-sensor has a potential to efficiently detect structural damage. In this technique, a PZT actuator-sensor patch is bonded on a structure. Through the measurement of its electrical impedance, which is related to the mechanical impedance of the structure being bonded, the change in structural properties due to damage can be detected. This paper presents the use of a PZT actuator-sensor in conjunction with numerical model-based methodology in structural health monitoring to quantitatively detect damage of bolted joints. The structure used in this study consists of two aluminium beams connected by a bolted joint. The damage was simulated by loosening the bolts. To quantitatively monitor the damage, a numerical model of the structure was formulated. A spectral element method (SEM), based on a wave propagation approach, was used to model the structure. A bonded-PZT beam and a bolted joint element were developed by using the SEM. The equations of motion were derived by using Hamilton's principle and then the spectral element matrices were formulated. Experimental results show the effectiveness of this method to detect the damage. By using the proposed model, the loosening of bolts can be quantitatively identified as the change in stiffness and damping at the bolted joint, indicating a high potential of this method in order to quantitatively monitor structural damage.

A Review Paper on Looseness Detection Methods in Bolted Structures

“…In addition to the studies on modeling of this method, there have been other researchers who conducted studies on adequacy of this method in detection and evaluation of looseness of bolted structures. Ritdumrongkul et al, besides modeling the electrical impedance of a structure, studied the efficiency of the method empir- ically, having a wave dispersal approach; while they provided indices to quantify the amount of looseness, they examined the sensitivity of indices to firmness and attenuation of joints (Ritdumrongkul, et al, 2004). Providing an index for evaluation of the looseness of bolts, Park et al surveyed the efficiency of the method in detecting looseness in bolted joints of pipelines (Overly, et al, 2007;Park, et al, 2001).…”

Damage Detection of Refractory Based on Principle Component Analysis and Gaussian Mixture Model

“…Structural health monitoring (SHM) has made significant advances in the past decades [1][2][3][4][5][6][7][8]. Monitoring of refractories, which are widely used in furnace, iron, and steel industries due to their ability to gain strength rapidly and to withstand aggressive environments and high temperature [9], receives increasing attention [10][11][12][13].…”

A Smart Washer for Bolt Looseness Monitoring Based on Piezoelectric Active Sensing Method

“…The analytical relationship between the piezoelectric impedance and the mechanical impedance of the host structure was established for the first time. Sopon et al [18] used a piezoelectric transducer (PZT) as an actuator-sensor collectively in conjunction with the numerical model-based spectral element method (SEM) in structural health monitoring to quantitatively detect damage of bolted joints. By analyzing the characteristics of the piezoelectric element under the bolt looseness condition, Gao et al [19] concluded that the conductance of the piezoelectric patches changes significantly under the high-frequency (more than 50 kHz) voltage excitation.…”