Hybrid bolt-loosening detection in wind turbine tower structures by vibration and impedance responses

Nguyen, Tuan-Cuong; Huynh, Thanh‐Canh; Yi, Jin‐Hak; Kim, Jeong-Tae

doi:10.12989/was.2017.24.4.385

Cited by 35 publications

(35 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Major advantages of the impedance technique include self-excitation and examination without external loads, cost-effective sensors and cheap data acquisition system, high sensitivity to small damage sizes, and autonomous and real-time monitoring. Various experimental and numerical studies in lab-scale and on real structures have demonstrated the practicality of the impedance-based SHM technique [10,11,12,13,14,15,16,17].…”

Section: Introductionmentioning

confidence: 99%

Tension Force Estimation in Axially Loaded Members Using Wearable Piezoelectric Interface Technique

Ryu

Huynh

Kim

2018

Sensors

Self Cite

View full text Add to dashboard Cite

Force changes in axially loaded members can be monitored by quantifying variations in impedance signatures. However, statistical damage metrics, which are not physically related to the axial load, often lead to difficulties in accurately estimating the amount of axial force changes. Inspired by the wearable technology, this study proposes a novel wearable piezoelectric interface that can be used to monitor and quantitatively estimate the force changes in axial members. Firstly, an impedance-based force estimation method was developed for axially loaded members. The estimation was based on the relationship between the axial force level and the peak frequencies of impedance signatures, which were obtained from the wearable piezoelectric interface. The estimation of the load transfer capability from the axial member to the wearable interface was found to be an important factor for the accurate prediction of axial force. Secondly, a prototype of the wearable piezoelectric interface was designed to be easily fitted into existing axial members. Finally, the feasibility of the proposed technique was established by assessing tension force changes in a numerical model of an axially loaded cylindrical member and a lab-scale model of a prestressed cable structure.

show abstract

Section: Introductionmentioning

confidence: 99%

Tension Force Estimation in Axially Loaded Members Using Wearable Piezoelectric Interface Technique

Ryu

Huynh

Kim

2018

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

“…Nowadays, the SHM systems for WTs are mostly deployed to blades [7] and tower [8] but research of SHM for offshore support structures is still scarce [9]. The state of the art in this very specific area has three main research lines: (i) model-based, using, for example, the finite element method as in [10][11][12]; (ii) data-based using solely experimental and/or real data; and (iii) a hybrid approach that makes use of real and/or experimental data and numerical models.…”

Section: Introductionmentioning

confidence: 99%

Damage Diagnosis for Offshore Wind Turbine Foundations Based on the Fractal Dimension

2020

View full text Add to dashboard Cite

Cost-competitiveness of offshore wind depends heavily in its capacity to switch preventive maintenance to condition-based maintenance. That is, to monitor the actual condition of the wind turbine (WT) to decide when and which maintenance needs to be done. In particular, structural health monitoring (SHM) to monitor the foundation (support structure) condition is of utmost importance in offshore-fixed wind turbines. In this work a SHM strategy is presented to monitor online and during service a WT offshore jacket-type foundation. Standard SHM techniques, as guided waves with a known input excitation, cannot be used in a straightforward way in this particular application where unknown external perturbations as wind and waves are always present. To face this challenge, a vibration-response-only SHM strategy is proposed via machine learning methods. In this sense, the fractal dimension is proposed as a suitable feature to identify and classify different types of damage. The proposed proof-of-concept technique is validated in an experimental laboratory down-scaled jacket WT foundation undergoing different types of damage.

show abstract

“…Bolt-loosening in a bolted joint can be monitored via its EM impedance responses, measured by piezoelectric sensors or piezoelectric washers [ 15 , 18 , 19 , 20 , 21 , 22 ]. Because the EM impedance correlates with the structural properties of a bolted connection, any damage occurrence could be detected via observing the changes in measured impedance data.…”

Section: Introductionmentioning

confidence: 99%

Preload Monitoring in Bolted Connection Using Piezoelectric-Based Smart Interface

Huynh

Dang

Kim

2018

Sensors

Self Cite

View full text Add to dashboard Cite

In this study, a preload monitoring method using impedance signatures obtained from a piezoelectric-based smart interface is presented for bolted girder connections. Firstly, the background theory of the piezoelectric-based smart interface and its implementation into the health monitoring of bolted connections are outlined. A simplified electro-mechanical (EM) impedance model of a smart interface-embedded bolted connection system is formulated to interpret a mechanistic understanding of the EM impedance signatures under the effect of bolt preload. Secondly, finite element modeling of a bolted connection is carried out to show the numerical feasibility of the presented method, and to predetermine the sensitive frequency band of the impedance signatures. Finally, impedance measurements are conducted on a lab-scaled bolted girder connection, to verify the predetermined sensitive frequency range and to assess the bolt preload changes in the test structure.

show abstract

Hybrid bolt-loosening detection in wind turbine tower structures by vibration and impedance responses

Cited by 35 publications

References 23 publications

Tension Force Estimation in Axially Loaded Members Using Wearable Piezoelectric Interface Technique

Tension Force Estimation in Axially Loaded Members Using Wearable Piezoelectric Interface Technique

Damage Diagnosis for Offshore Wind Turbine Foundations Based on the Fractal Dimension

Preload Monitoring in Bolted Connection Using Piezoelectric-Based Smart Interface

Contact Info

Product

Resources

About