Damage detection capabilities of strain-based displacement methods in beam-like structures (Conference Presentation)

The value of using permanently installed monitoring systems for managing the life of an engineering asset is determined by the confidence in its damage detection capabilities. A framework is proposed that integrates detection data from permanently installed monitoring systems with probabilistic structural integrity assessments. Probability of detection (POD) curves are used in combination with particle filtering methods to recursively update a distribution of postulated defect size given a series of negative results (i.e. no defects detected). The negative monitoring results continuously filter out possible cases of severe damage, which in turn updates the estimated probability of failure. An implementation of the particle filtering method that takes into account the effect of systematic uncertainty in the detection capabilities of a monitoring system is also proposed, addressing the problem of whether negative measurements are simply a consequence of defects occurring outside the sensors field of view. A simulated example of fatigue crack growth is used to demonstrate the proposed framework. The results demonstrate that permanently installed sensors with low susceptibility to systematic effects may be used to maintain confidence in fitness-for-service while relying on fewer inspections. The framework provides a method for using permanently installed sensors to achieve continuous assessments of fitness-for-service for improved integrity management.

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An On-Line Multiway Approach to In-Situ NDI Looking at the PZL-130TCII

Fatigue of Aircraft Structures ◽

10.2478/fas-2013-0001 ◽

2014 ◽

Vol 2013 (5) ◽

pp. 5-11 ◽

Cited By ~ 1

Author(s):

Krzysztof Dragan ◽

Michał Dziendzikowski ◽

Artur Kurnyta ◽

Adam Latoszek ◽

Andrzej Leski ◽

...

Keyword(s):

Damage Detection ◽

Hot Spots ◽

Lamb Waves ◽

Holistic Approach ◽

Growth Monitoring ◽

Damage Growth ◽

On Line ◽

Detection Capabilities ◽

Main Component

Abstract Providing a reliable and universal Structural Health Monitoring (SHM) system allowing for remote aircraft inspections and a reduction of maintenance costs is a major challenge confronting the aerospace industry today. SHM based on guided Lamb waves is one of the approaches capable of addressing the issue while satisfying all the associated requirements. This paper presents a holistic approach to the continuous real time damage growth monitoring and early damage detection in aircraft structure. The main component of the system is a piezoelectric transducers (PZT) network. It is complemented by other SHM methods: Comparative Vacuum Monitoring (CVMTM) and Resistance Gauges at selected aircraft hot spots. The paper offers the description of damage detection capabilities including the analysis of data collected from the PZL-130 Orlik aircraft full-scale fatigue test.

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Damage Detection Capabilities Based on New Signal Processing Approach

45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics & Materials Conference ◽

10.2514/6.2004-1952 ◽

2004 ◽

Author(s):

Len Gelman ◽

Ivan Petrunin ◽

Michael Sanderson ◽

Chris Thompson

Keyword(s):

Signal Processing ◽

Damage Detection ◽

Processing Approach ◽

Detection Capabilities

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Fatigue Cracks Detection using PZT Transducers under the Influence of Uncertain Environmental Factors

Fatigue of Aircraft Structures ◽

10.1515/fas-2016-0010 ◽

2016 ◽

Vol 2016 (8) ◽

pp. 111-115 ◽

Cited By ~ 1

Author(s):

Michal Dziendzikowski ◽

Slawomir Klimaszewski ◽

Krzysztof Dragan

Keyword(s):

Damage Detection ◽

Fatigue Test ◽

Fatigue Cracks ◽

Qualitative Assessment ◽

Growth Monitoring ◽

Damage Indices ◽

Alternative Approach ◽

Controllable Factors ◽

Detection Capabilities

AbstractThis paper presents technique for qualitative assessment of fatigue crack growth monitoring, utilizing guided elastic waves generated by the sparse PZT piezoelectric transducers network in the pitch – catch configuration. Two Damage Indices (DIs) correlated with the total energy received by a given sensor are used to detect fatigue cracks and monitor their growth. The indices proposed carry marginal signal information content in order to decrease their sensitivity with respect to other undesired non-controllable factors which may distort the received signal. The reason for that is to limit the false calls ratio which besides the damage detection capability of a system, plays a crucial role in applications. However, even such simplified damage indices can alter over a long term, leading to the misclassification problem. Considering a single sensing path, it is very difficult to distinguish whether the resultant change of DIs is caused by a damage or due to decoherence of these DIs. Therefore, assessment approaches based on threshold levels fixed separately for DIs obtained on each of the sensing paths, would eventually lead to a false call. An alternative approach is to compare changes of DIs for all sensing paths. Developing damage distorts the signal only for the sensing paths in its proximity. In order to decrease the misclassification risk, a method of compensating such DIs drift is proposed. The main features and damage detection capabilities of this method will be demonstrated by conducting a laboratory fatigue test of an aircraft panel. The proposed approach has been verified on a real structure during fatigue test of a helicopter tail boom.

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Damage Detection in Offshore Platforms Using Vibration Information

Journal of Energy Resources Technology ◽

10.1115/1.3231263 ◽

1986 ◽

Vol 108 (2) ◽

pp. 97-106 ◽

Cited By ~ 6

Author(s):

F. Shahrivar ◽

J. G. Bouwkamp

Keyword(s):

Damage Detection ◽

Oil And Gas ◽

Gas Production ◽

Offshore Platforms ◽

Oil And Gas Production ◽

Mass Eccentricity ◽

Detection Capabilities ◽

Offshore Oil And Gas ◽

Offshore Oil ◽

Mass Increase

Damage detection based on changes in dynamic characteristics is considered for eight-legged k-braced steel offshore oil and gas production towers. Both experimental and analytical results are presented to improve damage detection capabilities. A 1/50th scale plastic model representing the structural system of a typical full-scale tower in 218 ft (66m) of water is used for the studies. Effects of severance of diagonal bracing members on selected vibration frequencies and mode shape parameters measurable at the deck are investigated. The effects of changes in deck mass, increase in jacket mass, and deck mass eccentricity on the selected parameters are also investigated and are shown to be different from the effects of damage.

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Damage Detection on Typical Aeronautical Structures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.293-294.677 ◽

2005 ◽

Vol 293-294 ◽

pp. 677-684

Author(s):

Rosamaria Rodríguez ◽

A. Yarza ◽

J. López-Díez ◽

C. Cuerno-Rejado ◽

A. Güemes

Keyword(s):

Damage Detection ◽

Damage Identification ◽

Structural Characteristics ◽

False Alarms ◽

Complex Geometries ◽

Identification Methods ◽

Detection Capabilities ◽

Aluminium Sheets ◽

Modal Updating ◽

Detection Technologies

The paper pursues the exploration of the feasibility and reliability of current damage detection technologies, evaluating their detection capabilities, environmental factors effects, false alarms rate, adaptability to complex geometries, etc. The method to be used is based on finite element modal updating. Three aspects, as outlined below, are covered: testing samples will be aluminium sheets (0.6m x 0.4m x 1.6mm) strengthened with riveted L-shaped stiffeners. Data will be presented from the undamaged specimens. Secondly, the testing of the samples with damage simulated at different places by temporary removal of specific rivets, thus affecting the overall structural characteristics of the structure. The models used for damage identification methods will be fine tuned to properly detect the simulated damages. Finally, using this information, the paper resumes the capabilities of the method to detect and locate the simulated damage.

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DAMAGE DETECTION OF TRUSS-LIKE STRUCTURES USING WAVELET TRANSFORMS

Modern Physics Letters B ◽

10.1142/s0217984908016017 ◽

2008 ◽

Vol 22 (11) ◽

pp. 1165-1170 ◽

Cited By ~ 1

Author(s):

GAO-PING WANG ◽

YONG HONG ◽

DONG-PYO HONG ◽

YOUNG-MOON KIM

Keyword(s):

Damage Detection ◽

Smart Materials ◽

Wavelet Transforms ◽

Experimental Methods ◽

Guided Wave ◽

Numerical Results ◽

Truss Structures ◽

Complex Structures ◽

Detection Capabilities ◽

Methods Numerical

This study deals with the application of wavelet transforms to the damage detection of truss-like structures. The principles of damage detection by using the wavelet transforms are interpreted and the damage detection capabilities of wave transforms for cracks are demonstrated by numerical and experimental methods. Numerical simulation in combination with the wavelet transforms provides reliable numerical results and the guided wave method using smart materials enables the experimental verification of the numerical results. The basic component elements of truss structures, i.e., beams, are studied first, and subsequently complex structures are considered. The information extracted from the simulation data by using the wavelet transforms shows considerably accurate signatures for localization of damages. In particular, the study considers the influence of structural discontinuities and loading points on damage detection of crack localization. The information extracted from the signal by using the numerical and experimental methods employing the wavelet transforms shows the robustness of the methods in detecting damages in simple and complex structures.

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