scholarly journals Detecting of the Longitudinal Grouting Quality in Prestressed Curved Tendon Duct Using Piezoceramic Transducers

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1212 ◽  
Author(s):  
Tianyong Jiang ◽  
Bin He ◽  
Yaowen Zhang ◽  
Lei Wang
Keyword(s):  
Lead Zirconate Titanate ◽  
Wavelet Packet ◽  
Lead Zirconate ◽  
Stress Waves ◽  
Longitudinal Plane ◽  
Power Spectral ◽  
Experimental Process ◽  
The Difference ◽  
Grouting Materials

To understand the characteristics of longitudinal grouting quality, this paper developed a stress wave-based active sensing method using piezoceramic transducers to detect longitudinal grouting quality of the prestressed curved tendon ducts. There were four lead zirconate titanate (PZT) transducers installed in the same longitudinal plane. One of them, mounted on the bottom of the curved tendon duct, was called as an actuator for generating stress waves. The other three, pasted on the top of the curved tendon duct, were called as sensors for detecting the wave responses. The experimental process was divided into five states during the grouting, which included 0%, 50%, 75%, 90%, and 100% grouting. The voltage signals, power spectral density (PSD) energy and wavelet packet energy were adopted in this research. Experimental results showed that all the amplitudes of the above analysis indicators were small before the grouting reached 90%. Only when the grouting degree reached the 100% grouting, these parameters increased significantly. The results of different longitudinal PZT sensors were mainly determined by the distance from the generator, the position of grouting holes, and the fluidity of grouting materials. These results showed the longitudinal grouting quality can be effectively evaluated by analyzing the difference between the signals received by the PZT transducers in the curved tendon duct. The devised method has certain application value in detecting the longitudinal grouting quality of prestressed curved tendon duct.

Ion Beam Figuring Fabricate Effect with Different Removal Sizes

2013 ◽  
Vol 552 ◽  
pp. 142-146
Author(s):  
Yong Qiang Gu
Keyword(s):  
Spatial Frequency ◽  
Ion Beam ◽  
Influence Factors ◽  
Frequency Range ◽  
Surface Errors ◽  
Power Spectral ◽  
The Difference ◽  
Lens Surface ◽  
Ion Beam Figuring

Ion Beam Figure (IBF) is believed to be one of the most effective technics that can fabricate lens with nano or even sub-nano accuracy. For different sizes of IBF removal functions, the correct effects in different spatial frequency range are different. Power Spectral Density (PSD) curve can describe surface errors in full spatial frequency range, so it is a very convenient way to evaluate the quality of lens’ surface. In this paper, firstly, the principles of IBF and PSD are introduced briefly; Secondly, IBF removal functions with sizes from 2 mm to 15 mm are generated. A lens with surface error more than PV value 400nm is simulated with different sizes of IBF removal functions by Lucy-Richardson algorithm. Finally, experiments are done by IBF plant. A lens is fabricated by different sizes of removal functions and the fabricate results are tested by interferometer precisely and calculated to PSD curves. By the comparison of these curves, the IBF fabricate effects with different removal sizes are analyzed, which show that the smaller the removal size, the better the removal effect in higher spatial frequency range, but in the meantime, it will take a much longer time. Also the reasons of the difference between theory simulation and actual fabrication result are taken into account, and several influence factors are analyzed.

scholarly journals Piezoelectric Properties of Lead Zirconate Titanate Ceramics at Low and High Temperatures

2020 ◽  
Author(s):  
Mitsuhiro Okayasu ◽  
Masakazu Okawa
Keyword(s):  
Thermal Stress ◽  
Lead Zirconate Titanate ◽  
Domain Switching ◽  
Low Voltage ◽  
Lead Zirconate ◽  
Negative Voltage ◽  
Zirconate Titanate ◽  
Positive Voltage ◽  
Warming Rate ◽  
The Difference

Abstract The material properties and damage characteristics of lead zirconate titanate (PZT) ceramics were investigated at various temperatures (–190 °C to 180 °C). A positive voltage was obtained when the sample was cooled from 20 °C to –190 °C, while a negative voltage was obtained when the sample was warmed from –190 °C to 180 °C. The difference between the positive and negative values depended on the thermal stress. Compressive stress generated a more positive voltage in the cooling process, while tensile stress led to a more negative voltage in the warming process). The voltage values also depended on the cooling (or warming) rate of the sample, e.g., the greater the cooling (or warming) rate, the greater the voltage. When cyclic loading was conducted mechanically at –190 °C, the voltage reduced, but it was recovered after warming to 20 °C. Damage of the PZT ceramic (90° domain switching) was detected when the sample was cooled to –190 °C. This was due to the high thermal stress, resulting in a low voltage.

LTCC Piezoelectric Transducer for Energy Harvesting

2015 ◽  
Vol 2015 (CICMT) ◽  
pp. 000105-000111
Author(s):  
Arkadiusz P. Dabrowski ◽  
Slawomir Owczarzak ◽  
Henryk Roguszczak ◽  
Leszek J. Golonka
Keyword(s):  
Energy Harvesting ◽  
Output Power ◽  
Lead Zirconate Titanate ◽  
Piezoelectric Transducer ◽  
Lead Zirconate ◽  
Mean Power ◽  
Optimum Load ◽  
Resonance Frequencies ◽  
The Mean ◽  
The Difference

In this paper, design, technology and properties of multi cantilever transducer for energy harvesting application were described. The piezoelectric transducer was made in LTCC (Low Temperature Cofired Ceramics) technology using PZT (Lead Zirconate-Titanate) based tape. In such devices the highest power can be reached at resonance frequencies of the cantilevers. Eight bimorph transducers with lengths corresponding to 33, 50, 58, 66, 75, 82, 91 and 100 Hz resonant frequency, were designed. The transducers were polarized in serial or parallel configuration. To avoid voltage reduction in the system of a few piezoelectric bimorphs, rectifiers were applied for each cantilever. Transducers had optimum resistance in ranges of 60–140 kΩ and 300–600 kΩ for bimorphs poled in parallel and serial configuration, respectively. The mean output power under sinusoidal excitation with 20 μm vibration amplitude calculated from all maxima at resonant frequencies for optimum load, were equal to 10.3 μW and 12.4μW for parallel and serial configurations with rectifier. Without rectifier the values were equal to 18.2 μW for both the transducers. In case of mean output power, the difference between both the transducers was not really significant, however at higher frequency the maximum power was higher for serial configuration. Besides, the output voltage obtained in serial bimorph was higher than in parallel one. The mean power density for all the resonant peaks measured at 0.41 g was equal to 210 μW/cm3/g and 360 μW/cm3/g with and without rectifier, respectively.

scholarly journals Multi-Scale Stress Wave Simulation for Aggregates Segregation Detection of Concrete Core in Circular CFST Coupled with PZT Patches

Materials ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1223 ◽  
Author(s):  
Hongbing Chen ◽  
Bin Xu ◽  
Yilung Mo ◽  
Tianmin Zhou
Keyword(s):  
Stress Wave ◽  
Lead Zirconate Titanate ◽  
Coupling Effect ◽  
Wavelet Packet ◽  
Lead Zirconate ◽  
Stress Wave Propagation ◽  
Voltage Response ◽  
Concrete Aggregate ◽  
Concrete Core ◽  
Multi Scale

In this study, the numerical investigation of the detectability of concrete aggregate segregation in circular concrete-filled steel tubulars (CCFST) based on piezoelectric lead zirconate titanate (PZT) measurement is performed. The stress wave propagation in the concrete core of circular CCFST excited with a surface-mounted PZT actuator is studied with multi-scale and multi-physical field coupling analysis. The piezoelectric effect of PZT patches and its coupling effect with CFSTs are considered. Numerical concrete modeling technology is employed to construct the concrete core composed of randomly distributed aggregates with and without aggregate segregation at different levels, mortar, and an interfacial transition zone (ITZ). The effects of the random distribution of elliptical aggregates, aggregate segregation, and the existence of ITZ in the concrete core on the wave fields in the cross-section and the corresponding voltage response of the embedded PZT sensor are discussed. An evaluation index based on wavelet packet analysis on the output voltage response is defined, and its sensitivity to concrete aggregate segregation is systematically investigated. The multi-scale and multi-physics coupling simulation results indicate that concrete aggregate segregation in the concrete core of CFST members can be efficiently detected based on the stress wave measurement with a PZT sensor.

scholarly journals Microstructure of Pulsed-Laser Deposited Pzt on Polished and Annealed Mgo Substrates

1996 ◽  
Vol 433 ◽  
Author(s):  
Simon L. King ◽  
Luigi G. Coccia ◽  
J.G.E. Gardeniers ◽  
Ian W. Boyd
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Lead Zirconate Titanate ◽  
Pulsed Laser ◽  
Lead Zirconate ◽  
The Other ◽  
Crystalline Quality ◽  
Pzt Films ◽  
Atomically Flat

AbstractThin films of Lead-Zirconate-Titanate (PZT) have been grown by pulsed-laserdeposition (PLD) onto polished MgO substrates both with and without pre-annealing.The surface morphology of polished MgO substrates, which are widely used for deposition, is examined by AFM. Commercially available, mechanically-polished substrates are shown to be microscopically very rough and seem unlikely to present a surface suitable for the growth of the highest quality thin films. Annealed MgO substrates, on the other hand, comprise atomically flat terraces. The use of annealed substrates is found to enhance considerably the crystalline quality of PZT films deposited thereon.

scholarly journals A New Method to Perform Direct Efficiency Measurement and Power Flow Analysis in Vibration Energy Harvesters

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2388
Author(s):  
Jan Kunz ◽  
Jiri Fialka ◽  
Stanislav Pikula ◽  
Petr Benes ◽  
Jakub Krejci ◽  
...  
Keyword(s):  
Lead Zirconate Titanate ◽  
Polyvinylidene Fluoride ◽  
Power Flow ◽  
Flow Analysis ◽  
Lead Zirconate ◽  
Input Power ◽  
Mechanical Power ◽  
Vibration Source ◽  
Energy Harvesters ◽  
The Difference

Measuring the efficiency of piezo energy harvesters (PEHs) according to the definition constitutes a challenging task. The power consumption is often established in a simplified manner, by ignoring the mechanical losses and focusing exclusively on the mechanical power of the PEH. Generally, the input power is calculated from the PEH’s parameters. To improve the procedure, we have designed a method exploiting a measurement system that can directly establish the definition-based efficiency for different vibration amplitudes, frequencies, and resistance loads. Importantly, the parameters of the PEH need not be known. The input power is determined from the vibration source; therefore, the method is suitable for comparing different types of PEHs. The novel system exhibits a combined absolute uncertainty of less than 0.5% and allows quantifying the losses. The approach was tested with two commercially available PEHs, namely, a lead zirconate titanate (PZT) MIDE PPA-1011 and a polyvinylidene fluoride (PVDF) TE LDTM-028K. To facilitate comparison with the proposed efficiency, we calculated and measured the quantity also by using one of the standard options (simplified efficiency). The standard concept yields higher values, especially in PVDFs. The difference arises from the device’s low stiffness, which produces high displacement that is proportional to the losses. Simultaneously, the insufficient stiffness markedly reduces the PEH’s mechanical power. This effect cannot be detected via the standard techniques. We identified the main sources of loss in the damping of the movement by the surrounding air and thermal losses. The latter source is caused by internal and interlayer friction.

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

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 41 ◽  
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.

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

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.

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