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

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.

Download Full-text

Monitoring of Epoxy-Grouted Bonding Strength Development between an Anchored Steel Bar and Concrete Using PZT-Enabled Active Sensing

Sensors ◽

10.3390/s19092096 ◽

2019 ◽

Vol 19 (9) ◽

pp. 2096 ◽

Cited By ~ 8

Author(s):

Jian Jiang ◽

Chuang Hei ◽

Qian Feng ◽

Jinwei Jiang

Keyword(s):

Lead Zirconate Titanate ◽

Bonding Strength ◽

Concrete Beams ◽

Wavelet Packet ◽

Concrete Specimen ◽

Strength Development ◽

Active Sensing ◽

Pull Out ◽

Steel Bar ◽

Steel Bars

Anchored steel bars have been widely used in retrofitting of existing concrete structures. The bonding strength between the anchored steel bar and the concrete is critical to the integrity of the strengthened concrete structure. This paper presents a method to monitor epoxy-grouted bonding strength development by using a piezoceramic-enabled active sensing technique. One concrete beam with an anchored steel bar was involved in the monitoring test, and two concrete beams with six anchored steel bars were used in the pull-out test. To enable the active sensing, a Lead Zirconate Titanate (PZT) patch was bonded to the surface of the exposed end, and piezoceramic smart aggregates were embedded in each concrete specimen. During the monitoring experiment, signals from PZT sensors and smart aggregates were acquired at intervals of 0, 20, 40, 60, 80, and 100 min. In addition, a pull-out test was performed on each of the remaining six anchored steel bars in the two concrete beams, while the signal was recorded in the test. Furthermore, a wavelet packet analysis was applied to analyze the received signal energies to investigate the bonding strength development between the concrete and the anchored steel bar during the epoxy solidification process. The test results demonstrate the effectiveness of the proposed method in monitoring the bonding strength development between the anchored steel bar and the concrete, using the PZT-enabled active sensing.

Download Full-text

Monitoring of Interfacial Debonding of Concrete Filled Pultrusion-GFRP Tubular Column Based on Piezoelectric Smart Aggregate and Wavelet Analysis

Sensors ◽

10.3390/s20072149 ◽

2020 ◽

Vol 20 (7) ◽

pp. 2149 ◽

Cited By ~ 3

Author(s):

Wenwei Yang ◽

Xia Yang ◽

Shuntao Li

Keyword(s):

Remote Sensing ◽

Real Time ◽

Lead Zirconate Titanate ◽

Damage Index ◽

Pulse Excitation ◽

Interface Debonding ◽

Active Monitoring ◽

Monitoring Method ◽

Damage Level ◽

Smart Aggregate

The concrete filled pultrusion-GFRP (Glass Fiber Reinforced Polymer) tubular column (CFGC) is popular in hydraulic structures or regions with poor environmental conditions due to its excellent corrosion resistance. Considering the influence of concrete hydration heat, shrinkage, and creep, debonding may occur in the interface between the GFRP tube and the concrete, which will greatly reduce the cooperation of the GFRP tube and concrete, and will weaken the mechanical property of CFGC. This paper introduces an active monitoring method based on the piezoelectric transducer. In the active sensing approach, the smart aggregate (SA) embedded in the concrete acted as a driver to transmit a modulated stress wave, and the PZT (Lead Zirconate Titanate) patches attached on the outer surface of CFGC serve as sensors to receive signals and transfer them to the computer for saving. Two groups of experiments were designed with the different debonding areas and thicknesses. The artificial damage of CFGC was identified and located by comparing the value of the delay under pulse excitation and the difference of wavelet-based energy under sweep excitation, and the damage indexes were defined based on the wavelet packet energy to quantify the level of the interface damage. The results showed that the debonding damage area of CFGC can be identified effectively through the active monitoring method, and the damage index can accurately reflect the damage level of the interface of GFRP tube and concrete. Therefore, this method can be used to identify and evaluate the interface debonding of CFGC in real time. In addition, if the method can be combined with remote sensing technology, it can be used as a real-time remote sensing monitoring technology to provide a solution for interface health monitoring of CFGC.

Download Full-text

Detecting Debonding between Steel Beam and Reinforcing CFRP Plate Using Active Sensing with Removable PZT-Based Transducers

Sensors ◽

10.3390/s20010041 ◽

2019 ◽

Vol 20 (1) ◽

pp. 41 ◽

Cited By ~ 6

Author(s):

Jian Jiang ◽

Jinwei Jiang ◽

Xiaowei Deng ◽

Zifeng Deng

Keyword(s):

Stress Wave ◽

Lead Zirconate Titanate ◽

Wavelet Packet ◽

Experimental Studies ◽

Steel Structure ◽

Steel Structures ◽

Lead Zirconate ◽

Steel Beam ◽

Active Sensing ◽

Cfrp Plate

Carbon fiber reinforced polymer (CFRP) plates are widely used to retrofit or reinforce steel structures, and the debonding damage between the steel structure and the CFRP plate is a typical failure in strengthening steel structures. This paper proposes a new approach to detecting debonding between a steel beam and a reinforcing CFRP plate by using removable lead zirconate titanate (PZT)-based transducers and active sensing. The removable PZT-based transducers are used to implement the active sensing approach, in which one transducer, as an actuator, is used to generate stress wave, and another transducer, as a sensor, is used to detect the stress wave that propagates across the bonding between the steel beam and the reinforcing CFRP plate. The bonding condition significantly influences the received sensor signal, and a wavelet-packet-based energy index (WPEI) is used to quantify the energy of the received signal to evaluate the severity of debonding between the steel beam and the reinforcing CFRP plate. To validate the proposed approach, experimental studies were performed, and two removable PZT-based transducers were designed and fabricated to detect the debonding between a steel beam and the reinforcing CRFP plate. The experimental results demonstrate the feasibility of the proposed method in detecting the debonding between a steel beam and the reinforcing CFRP plate using removable PZT-based transducers.

Download Full-text

Interface Debonding Detection of Precast Segmental Concrete Beams (PSCBs) Using Piezoceramic Transducer-Based Active Sensing Approach

Mathematical Problems in Engineering ◽

10.1155/2019/8725021 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

Yang Liu ◽

Ming Zhang ◽

Xinfeng Yin ◽

Chuang Hei ◽

Lei Wang

Keyword(s):

Concrete Beams ◽

Wavelet Packet ◽

Damage Index ◽

High Strength ◽

Frequency Domain Analysis ◽

Interface Debonding ◽

Active Sensing ◽

Periodic Loading ◽

Debonding Detection ◽

Epoxy Resin Adhesive

An active sensing approach using piezoceramic induced stress wave is proposed to provide monitoring and early warning for the development of interface debonding damage of precast segmental concrete beams (PSCBs). Three concrete specimens with toothed interfaces were fabricated and bonded with high-strength epoxy resin adhesive to form PSCBs. Smart aggregates (SAs) embedded in concrete specimens are used as actuators and sensors. The PSCBs are subjected to periodic loading with hydraulic jack to test the different degrees of debonding damage. The experimental results of time-domain and frequency-domain analysis clearly show that the amplitude of the signal received by the piezoceramic sensor is reduced when debonding crack occurs. The energy analysis and damage index based on wavelet packet can be used to determine the existence and severity of interface debonding damage in PSCBs. The experimental research validates the feasibility of monitoring the interface debonding damage in PSCBs using SA transducers based on active sensing technique.

Download Full-text

Experimental Research on Shear Failure Monitoring of Composite Rocks Using Piezoelectric Active Sensing Approach

Sensors ◽

10.3390/s20051376 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1376 ◽

Cited By ~ 1

Author(s):

Yang Liu ◽

Yicheng Ye ◽

Qihu Wang ◽

Weiqi Wang

Keyword(s):

Shear Failure ◽

Wavelet Packet ◽

Failure Process ◽

Damage Index ◽

Active Sensing ◽

Wavelet Packet Analysis ◽

Engineering Structures ◽

Damage Indices ◽

Monitoring Test ◽

Failure Monitoring

Underground space engineering structures are generally subject to extensive damages and significant deformation. Given that composite rocks are prone to shear failure, which cannot be accurately monitored, the piezoelectric active sensing method and wavelet packet analysis method were employed to conduct a shear failure monitoring test on composite rocks in this study. For the experiment, specimens were prepared for the simulation of the composite rocks using cement. Two pairs of piezoelectric smart aggregates (SAs) were embedded in the composite specimens. When the specimens were tested using the direct shear apparatus, an active sensing-based monitoring test was conducted using the embedded SAs. Moreover, a wavelet packet analysis was conducted to compute the energy of the monitoring signal; thus allowing for the determination of the shear damage index of the composite specimens and the quantitative characterization of the shear failure process. The results indicated that upon the shear failure of the composite specimens, the amplitudes and peak values of the monitoring signals decreased significantly, and the shear failure and damage indices of the composite specimens increased abruptly and approached a value of 1. The feasibility and reliability of the piezoelectric active sensing method, with respect to the monitoring of the shear failure of composite rocks, was therefore experimentally demonstrated in this study.

Download Full-text

Monitoring bond-slip behavior of CFRP-RCESC beams using piezoelectric active sensing method

Advances in Bridge Engineering ◽

10.1186/s43251-021-00046-7 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Tianyong Jiang ◽

Donghai Yu ◽

Min Xiao ◽

Lingyun Li ◽

Lei Wang

Keyword(s):

Reinforced Concrete ◽

Stress Wave ◽

Lead Zirconate Titanate ◽

Wavelet Packet ◽

Lead Zirconate ◽

Active Sensing ◽

Bond Slip ◽

Damage States ◽

Damage Process ◽

As Stress

AbstractCombination of carbon fiber reinforced polymer (CFRP) tendon and reinforced concrete encased steel composite (RCESC) beam can improve the workability and the energy dissipation capacity of members. In this paper, three RCESC beams reinforced with steel bars or CFRP bars were designed and fabricated to study the bond-slip behavior between I-shaped steel and CFRP reinforced concrete and the damage states between bond-slip interfaces of the beams. The lead zirconate titanate (PZT) patch as stress wave actuator, the smart aggregates (SAs) were installed in concrete as the sensors to collect the stress wave signal. A method based on piezoelectric active sensing was developed to monitor the bond-slip damage of CFRP-RCESC beam. The changes of responding signals were characterized in time- and frequency- domains. The characteristic information of bond-slip damage was further quantified by wavelet packet energy. Results show the bond-slip resistance of the CFRP-RCESC beams can be improved by increasing reinforcement ratio and elastic modulus of the main bars. The bond-slip damage process of the specimens can be effectively monitored by the active sensing method.

Download Full-text

Direct Current-Bias Dependence of Nonlinear Coefficients in Lead Zirconate Titanate Piezoelectric Ceramics

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj.113.642 ◽

2005 ◽

Vol 113 (1322) ◽

pp. 642-646 ◽

Cited By ~ 7

Author(s):

Shinjiro TASHIRO ◽

Wataru TOKUNAGA ◽

Keisuke ISHII ◽

Kunihiro NAGATA

Keyword(s):

Lead Zirconate Titanate ◽

Direct Current ◽

Piezoelectric Ceramics ◽

Lead Zirconate ◽

Zirconate Titanate ◽

Direct Current Bias

Download Full-text

Power-Generation Optimization Based on Piezoelectric Ceramic Deformation for Energy Harvesting Application with Renewable Energy

Energies ◽

10.3390/en14082171 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2171

Author(s):

Hyeonsu Han ◽

Junghyuk Ko

Keyword(s):

Power Generation ◽

Renewable Energy ◽

Energy Harvesting ◽

Piezoelectric Material ◽

Lead Zirconate Titanate ◽

Piezoelectric Ceramic ◽

Piezoelectric Element ◽

Piezoelectric Ceramics ◽

Lead Zirconate ◽

Piezoelectric Energy

Along with the increase in renewable energy, research on energy harvesting combined with piezoelectric energy is being conducted. However, it is difficult to predict the power generation of combined harvesting because there is no data on the power generation by a single piezoelectric material. Before predicting the corresponding power generation and efficiency, it is necessary to quantify the power generation by a single piezoelectric material alone. In this study, the generated power is measured based on three parameters (size of the piezoelectric ceramic, depth of compression, and speed of compression) that contribute to the deformation of a single PZT (Lead zirconate titanate)-based piezoelectric element. The generated power was analyzed by comparing with the corresponding parameters. The analysis results are as follows: (i) considering the difference between the size of the piezoelectric ceramic and the generated power, 20 mm was the most efficient piezoelectric ceramic size, (ii) considering the case of piezoelectric ceramics sized 14 mm, the generated power continued to increase with the increase in the compression depth of the piezoelectric ceramic, and (iii) For piezoelectric ceramics of all diameters, the longer the depth of deformation, the shorter the frequency, and depending on the depth of deformation, there is a specific frequency at which the charging power is maximum. Based on the findings of this study, PZT-based elements can be applied to cases that receive indirect force, including vibration energy and wave energy. In addition, the power generation of a PZT-based element can be predicted, and efficient conditions can be set for maximum power generation.

Download Full-text