A simple damage detection indicator using operational deflection shapes

Silva

et al. 2019

JCIS

Frequency response functions have been employed as damage-sensitive features in the vibration-based structural damage detection. However, the need for measuring the excitation forces arises as a remarkable limitation on the application of those features in real-world applications. As an alternative, transmissibility measurements can be explored as features with output-only nature, which implies the need for measuring only the response signals. In this paper, an output-only damage detection method is proposed, combining transmissibilities with kernel principal component analysis (KPCA). This technique is based on the pattern recognition paradigm for structural health monitoring, where feature extraction and feature classification phases are considered. In the first phase, the dimensionality of the transmissibilities is appropriately reduced by applying the KPCA algorithm. In the second phase, an outlier detection strategy is used to determine the condition of the instrumented structure. The possibility of clustering in the high-dimensional space mapped by KPCA is also reported and discussed. The proposed method is experimentally validated with transmissibilities acquired, under distinct structural conditions, from a laboratory steel beam instrumented with several accelerometers. The results demonstrate that the output-only method has high potential to be applied in a wide range of monitoring solutions, where economic issues and life-safety are primary motivations.

Section: Test Structure and Data Setsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Output-only structural damage detection based on transmissibility measurements and kernel principal component analysis

Silva

et al. 2019

JCIS

The International Journal of Acoustics and Vibration

“…In many applications of SHM, 1-5% white Gaussian noise is consid- ered to pollute the simulated vibration signals to consider the measurement and ambient noise. 15,33 Shu et al have considered 2-5% white Gaussian noise to the moving load response of the simplified railway bridge model. 15 In this work, 2-5% white Gaussian noise with zero mean and specified standard deviation are added to the vibration signals.…”

Section: Data Simulationmentioning

confidence: 99%

Damage Diagnosis of Steel Truss Bridges under Varying Environmental And Loading Conditions

Kumar¹,

Biswas²,

Dhang³

2019

In this paper, we propose a damage detection and localization algorithm for steel truss bridges using a data-driven approach under varying environmental and loading conditions. A typical steel truss bridge is simulated in ANSYS for data generation. Damage is introduced by reducing the stiffness of one or more members of the truss bridge. The simulated acceleration time-history signals are used for the purpose of damage diagnosis purpose. Vibration data collected from healthy bridges are processed through principal component analysis (PCA) to find the reduced size weighted feature vectors in model space. Unknown test vibration data (healthy or damaged) finds the closest match of its reduced size model from the training database containing only healthy vibration data. The residual error between the spread of closest healthy vibration data and unknown test vibration data is processed to determine damage location and severity of the damage to the structure. A comparative study between a proper orthogonal decomposition (POD) based damage detection algorithm and proposed algorithm is presented. The results show that the proposed algorithm is efficient to identify the damage location and assess the severity of damage, called as the Damage Index (DI), under varying environmental and moving load conditions.

Anais De XXXVI Simpósio Brasileiro De Telecomunicações E Processamento De Sinais

“…The response signals were fed into the multichannel data acquisition unit Brüel & Kjaer 2816 (PULSE) and analyzed with the Labshop 6.1 Pulse software installed on the attached laptop. The experimental setup is shown in Figure 1 and more details can be found in Sampaio et al [4]. The damage was simulated with a reduction in the height by a saw cut.…”

Section: Test Structure and Data Setsmentioning

confidence: 99%

“…Frequency response functions (FRFs) play an important role in the vibration-based damage detection area [2]. Many works have been employed the FRFs as features to generate some kind of damage indicators (DIs) that reveal the structural condition of monitored structures [3], [4]. However, the need for measuring the excitation forces arises as a remarkable limitation on the application of FRFs in real-world SHM solutions.…”

Section: Introductionmentioning

confidence: 99%

Applicability of an output-only structural damage detection based on transmissibility measurements and kernel principal component analysis

Santos¹,

Silva²,

Santos³

et al. 2018

Frequency response functions have been employed as damage-sensitive features in the vibration-based structural damage detection. The need for measuring the excitation forces arises as a remarkable limitation on the application of those features in real-world applications. Transmissibility measurements can be explored as features with output-only nature, which imply the need for measuring only the response signals. Thus, an output-only damage detection method is proposed, combining transmissibilities with kernel principal component analysis. The results performed on transmissibility measurements from a laboratory steel beam reveals that the output-only method has high potential to be applied in a wide range of monitoring solutions.