Real‐Time Monitoring of Timber‐Surface Crack Repair Using Piezoelectric Ceramics

Abstract

Real-time assessment of timber-surface crack repair is crucial to the stability and safety of timber structures. Epoxy resin was used to repair timber cracks, and the active sensing technique using piezoelectric ceramics was applied to monitor the repair process of timber surface cracks in real time. Sixteen wood samples were designed for axial compression tests and active monitoring tests. A pair of lead zirconate titanate patches was pasted on the surface of the timber specimens as actuators and sensors for signal transmission and reception, through wavelet packet analysis, the variations in the signal amplitude, and wavelet coefficients. The relationship between the wavelet packet energy of the monitoring signal and the ultimate bearing capacity of the specimens at different periods after grouting was established. Based on the root-mean-square deviation, the damage index, DI, was introduced to evaluate the repair degree of timber surface cracks quantitatively. The results showed that the active sensing method can evaluate the strength development in timber-surface crack repair in real time.

Crack Repair Model of Ancient Ceramics Based on Digital Image

“…e proposed method, the method in reference [9], and the method in reference [11] were used to conduct nondestructive testing of microdefect cracks in ceramic products, and the testing results are shown in Figure 7. By comparison, it can be seen that the proposed method can effectively eliminate the influence of noise and grinding texture in ceramic images, accurately extract the microdefect region of ceramic images, and increase the contrast between the image background region and the microdefect crack region.…”

“…With the rapid development of Internet, it has a wide application prospect. erefore, the detection and recovery of defects indicated by ceramics are particularly important in this industry [7][8][9][10][11][12].…”

Sensors, Signal, and Artificial Intelligent Processing

“…Crack can be treated as crucial for safety assessment. Epoxy resin has been used in [20], and the active sensing technique using piezoelectric ceramics is used to monitor cracks. Once wavelet method is applied, the relationship between the wavelet signal and bearing capacity after grouting is thus established.…”

Bonding performance monitoring between CFRP and timber column interfaces based on piezoelectric ceramics

“…Han et al [51] assessed the damage severity of timber specimens by PZT based on the mechanical impedance method to identify the location and size of the damage. Meng et al [52] investigated the repair of cracks on timber surfaces using piezoelectric ceramic active sensing. Xiong et al [53] combined the sensing technique based on piezoelectric ceramics with a visual domain network to quantitatively assess the damage condition of timber, and used deep neural network classification, which can effectively identify the crack condition of timber structures.…”