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Identification of bond behavior between FRP/steel bars and self-compacting concrete using piezoceramic transducers based on wavelet energy analysis

Zhou Lingzhu, Zheng Yu, Ii Haotian, Song Gangbing

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

96--111

EN

The civil infrastructures constructed using self-compacting concrete (SCC) reinforced with fiber-reinforced polymer (FRP) bars are advocated for engineering applications due to corrosion resistance and environmental-friendly performance. The bond behavior between FRP reinforcement and SCC is a significant factor affecting the serviceability and failure mechanism of this composite structure. However, it is hard to identify the damage mechanism and failure mode of the interface bond using the traditional test methods. Therefore, an effective monitoring method of interface damage using piezoceramic transducers is proposed in this paper. A series of pull-out tests were performed, and the test variables involved concrete materials and reinforcing bar types. A lead zirconate titanate (PZT) patch transducer acting as an actuator was bonded on the outer surface of reinforcing bars, and a piezoceramic smart aggregate transducer acting as a sensor was embedded in the SCC. A wavelet energy ratio index (WERI) is proposed to identify the damage mechanism of interface between reinforcing bars and SCC. The experimental test results reveal that the damage mechanism and failure mode of the bond between different reinforcing bars and concrete materials can be identified effectively and the peak of bond stress can be captured accurately by using WERI values.

2

Development of Active Vibration Control System for Circular Plate by Using the 2-Layer Piezo Disk Elements

Leniowska L., Leniowski R.

Mechanika / Akademia Górniczo-Hutnicza im. St. Staszica

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2003

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T. 22, z. 3

337-346

EN

An active vibration control system is proposed for suppressing small amplitude harmonic vibrations of a thin circular plate. This system integrates control algorithms, intelligent materials, hardware and software technologies. The mathematical model of the physical system is based upon the geometry and properties of an experimental set-up consisting of a hard-walled cylinder with a thin aluminium plate at one end. Primary excitation is provided by a Iow frequency loudspeaker installed centrally at the bottom of the cylinder. The vibrations of the plate are measured by the application of strain sensors. Intelligent materials such as 2-layer piezo disk elements (PZT) are used as the actuator. For the considered system, the OE (Output Error) method of discrete-time model identification for real-time active vibration control has been applied. On the basis of this model, the control algorithm based on pole-placement method has been developed. The simulation results show that the designed structure of a close-loop system provifeedback contrdes substantial vibration suppression.

3

Active control of circular plate vibration by using piezoceramic actuators

Leniowska L., Leniowski R.

Archives of Control Sciences

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2003

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Vol. 13, no. 4

445-457

EN

An active vibration control system is proposed for suppressing small amplitude harmonic vibrations of a thin circular plate. This system integrates control algorithms, intelligent materials hardware and software technologies. The mathematical model of the physical system is based upon the geometry and properties of an experimantal set-up consisting of a hard-walled cylinder with a thin aluminium plate at the end. Primary excitation is provided by a low frequency loudspeaker installed centrally at the bottom of the cylinder. The vibrations of the plate are measured by the application of strain sensors. Intelligent materials such as 2-layer piezo disk elements (PZT) are used as the actuator. For the considered system, the OE (Output Error) method of discrete-time model identyfication for real-time active vibration control has been applied. On the basis of this model, the control algorithm based on pole-placement method has been developed. The obtained results show that the designed structure of a closed-loop system provides substantial vibration suppression.

4

Wpływ ładunku przestrzennego na stabilność czestotliwości rezonansowej przetworników piezoceramicznych na bazie PZT

Bochenek D., Fesenko E. G., Gavrilyachasenko S. V., Leyderman A. V., Surowiak Z.

Elektronika : konstrukcje, technologie, zastosowania

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2000

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Vol. 41, nr 6

3-10

PL

Na przykładzie kilku czteroskładnikowych roztworów stałych na bazie PZT badano wpływ ładunku przestrzennego na temperaturową i czsowa stabilność rezonansowej (fr) oraz innych parametrów piezoelektrycznych. Temperaturowa stabilność fr wzrasta wraz ze wzrostem pola ładunku przestrzennego (Esc), czyli ze zmniejszaniem sie średnich rozmiarów ziarn oraz zwiększeniem porowatości i stopnia zdefektowania piezoceramiki. Obok pola ładunku przestrzennego (Esc) na temperaturowa syabilność fr, mają również wpływ wartości parametru spontanicznej deformacji ([delta]) i pola koercji (Ec). Ze wzrostem [delta] i Ec, czyli ze wzrostem twardości ferroelektrycznej, wzrasta stabilność czestotliwości rezonansowej (fr). Praktycznym osiągnięciem pracy jest opracowanie technologii drobnoziarnistej piezoceramiki o względnej temperaturowej zmianie czestotliwości rezonansowej ([delta fr)x100%<0,15% w zakresie temperatury 213 - 358 K. Taka piezoceramika może znaleźć zastosowanie w budowie pasmowych filtrów elektrycznych.

EN

On the basis of some four-component solid solutions on the PZT basis, the influence of a space charge on the temperature and time stability of the resonance frequency (fr) and other piezoelectric parameters were examined. Temperature stability fr, increases together with increase of the space charge field (Esc), so with decrease of average size of grains and with increase of porosity and the level of piezceramic defectivity. Despite the space charge field (Esc) the temperature stability of fr, is influenced also by the value of spontaneous deformation parameter ([delta]) and the coercion field (Ec). With the increase of [delta] and Ec that is with the increase of ferroelectric hardness the resonance frequency stability (fr) increases. The practical achievement of the work is elaborating the technology of fine-grained piezoceramic with the relative temperature change of resonance frequency ([delta fr)x100%<0,15% in the range of temperatures 213 - 358 K. Such piezoceramic can be used in the construction of band electric filters.