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American Society for Testing and Materials

A review of recent research on mechanics of multifunctional composite materials and structures

The paper provides a state of the art review of guided wave based structural health monitoring (SHM). First, the fundamental concepts of guided wave propagation and its implementation for SHM is explained. Following sections present the different modeling schemes adopted, developments in the area of transducers for generation, and sensing of wave, signal processing and imaging technique, statistical and machine learning schemes for feature extraction. Next, a section is presented on the recent advancements in nonlinear guided wave for SHM. This is followed by section on Rayleigh and SH waves. Next is a section on real-life implementation of guided wave for industrial problems. The paper, though briefly talks about the early development for completeness,. is primarily focussed on the recent progress made in the last decade. The paper ends by discussing and highlighting the future directions and open areas of research in guided wave based SHM.

https://iopscience.iop.org/article/10.1088/0964-1726/25/5/053001/pdf

Guided wave based structural health monitoring: A review

Electrospun nanofiber reinforced composites: a review

Data fusion and machine learning for industrial prognosis: Trends and perspectives towards Industry 4.0

Debonding detection in CFRP-reinforced steel structures using anti-symmetrical guided waves

The development of structural health monitoring (SHM) systems and their integration in actual structures has become a necessity as it can provide a robust and low-cost solution for monitoring the structural integrity of and the ability to predict the remaining life of structures. In this review, we aim at focusing on one of the important issues of SHM, the design, and implementation of sensor networks. Location and number of sensors, in any SHM system, are of high importance as they impact the system integration, system performance, and accuracy of assessment, as well as the total cost. Hence we are interested in shedding the light on the sensor networks as an essential component of SHM systems. The review discusses several important parameters including design and optimization of sensor networks, development of academic and commercial solutions, powering of sensors, data communication, data transmission, and analytics. Finally, we presented some successful case studies including the challenges and limitations associated with the sensor networks.

Sensor Networks for Structures Health Monitoring: Placement, Implementations, and Challenges—A Review

The present study aims at developing a robust non-destructive evaluation technique by using the scattering of ultrasonic guided waves for early detection and assessment of localised damage in bare rebars in the form of corrosion pits. The guided wave interaction with the pitting corrosion is numerically simulated by using finite element analysis, and the results are validated with experiments. The received signal contains several wave packets, which could be identified as various scattered modes that are generated from the edges of the corroded region. It is found that when the damage is placed at the centre of the rebar, several scattered wave modes superimpose to form two distinct wave packets in the received signal. A damage index is proposed by using these two distinct wave packets. It is shown that the proposed damage index method can be used successfully to monitor the axial extent and intensity of pitting corrosion in rebars. However, for the pitting corrosion that is situated at an arbitrary position, a different methodology, which utilises the differential time of arrival of various scattered wave modes, is proposed to identify the location of the pitting corrosion. Finally, a non-dimensional parameter, namely the scatter coefficient, is defined to analyse the energy contributions of various scatter modes. It is found that this scatter coefficient gradually increases with the mass loss and that the increment is pronounced when the corrosion pit is closer to the receiver location. The findings of the study can be used to identify the pitting corrosion in bare rebars.

Detection and assessment of pitting corrosion in rebars using scattering of ultrasonic guided waves

Mechanical and Electrical Characterisation of Steel Fiber and Carbon Black Engineered Cementitious Composites

This research reports a selective detecting and focusing approach for fatigue cracks through use of decomposition of the time reversal operator (DORT) in combination with nonlinear Lamb waves. In the proposed approach, the time reversal operator (TRO) is only decomposed at the second-harmonic frequency, which has been widely utilized in recent years to evaluate micro-damage, rather than the fundamental frequency in the traditional DORT method. Further, an imaging algorithm based on the total focus method is introduced to locate nonlinear scatterers. The proposed approach is experimentally investigated to locate two fatigue cracks with different fatigue cycles in an aluminum plate with a set of surface bounded piezoelectric (PZT) transducers. The results show that the significant eigenvalues are related to the fatigue cycles of fatigue cracks when the TRO is decomposed at the second-harmonic frequency, and the number of significant eigenvalues is exactly equal to the number of fatigue cracks. The two fatigue cracks are selectively located accurately and are also distinguished from linear scatterer by use of the proposed method.

Ye Lu

Papers

Debonding detection in CFRP-reinforced steel structures using anti-symmetrical guided waves

Sensor Networks for Structures Health Monitoring: Placement, Implementations, and Challenges—A Review

Detection and assessment of pitting corrosion in rebars using scattering of ultrasonic guided waves

Mechanical and Electrical Characterisation of Steel Fiber and Carbon Black Engineered Cementitious Composites

Nonlinear Lamb wave based DORT method for detection of fatigue cracks