Yong Huang¹, Hui Li¹, Jinping Ou^1,2

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.2, pp. 53-64, 2009, DOI:10.3970/icces.2009.012.053

Abstract A new damage identification method based on Fractal theory and wavelet packet transform is presented in the paper. The damage identification method utilize frequency-based domain message, time-based domain message and space based domain message effectively. NeXT method were first employed to reduce loading effect of random vibration measured from structures and then the vibration sinal were decomposed into the certain level wavelet packet components. For every time array of wavelet packet component then need to calculate the mean FD values as the ultimated FD values to reduce noise effect. The location of damage in the beam can be determined by… More >

I. Yoshida ¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.3, pp. 195-200, 2008, DOI:10.3970/icces.2008.006.195

Abstract A priori information is discussed in order to overcome the ill-posedness of damage detection. We compared Gauss and Laplace distributions to express the uncertainties of a priori information. Uncertainty level of a priori and observation information is related to the balance of a priori and observation terms in the objective function. Maximum likelihood method is used to determine the balance adaptively. The method is examined through numerical simulations of identification problem to detect damage of a bridge based on coupling vibration with moving vehicles. More >

C. Soutis¹, K. Diamanti¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 49-54, 2007, DOI:10.3970/icces.2007.001.049

Abstract A cost and time effective inspection strategy for in-service health monitoring of composites is demonstrated using the fundamental anti-symmetric A0 Lamb mode at frequencies of 15-20 kHz. In principle, this method involves analysis of the transmitted and/or reflected wave after interacting with the test-piece boundaries or discontinuities (defects). In the present work, the applicability of the technique to composite sandwich structures is explored. More >

Costas P. Providakis^1,*, Stavros E. Tsistrakis¹, Evangelos V. Liarakos¹

Structural Durability & Health Monitoring, Vol.12, No.4, pp. 257-279, 2018, DOI:10.32604/sdhm.2018.04607

Abstract In the present study a new structural health monitoring (SHM) technique is proposed as well as a new damage index based on 2-D error statistics. The proposed technique combines the electromechanical impedance technique (EMI) which is based on the use of piezoelectric Lead Zirconate Titanate (PZT) patches and Scanning Laser Doppler Vibrometry (SLDV) for damage detection purposes of concrete structures and early age monitoring. Typically the EMI technique utilizes the direct and inverse piezoelectric effect of a PZT patch attached to a host structure via an impedance analyzer that is used for both the actuation and sensing the response of… More >

Kong Fah Tee ^1,*

Structural Durability & Health Monitoring, Vol.12, No.3, pp. 129-147, 2018, DOI: 10.3970/sdhm.2018.04316

Abstract Structural health monitoring (SHM) is a vast, interdisciplinary research field whose literature spans several decades with focusing on condition assessment of different types of structures including aerospace, mechanical and civil structures. The need for quantitative global damage detection methods that can be applied to complex structures has led to vibration-based inspection. Statistical time series methods for SHM form an important and rapidly evolving category within the broader vibration-based methods. In the literature on the structural damage detection, many time series-based methods have been proposed. When a considered time series model approximates the vibration response of a structure and model coefficients… More >

Siddesha H¹, Manjunath N Hegde²

Structural Durability & Health Monitoring, Vol.11, No.1, pp. 17-41, 2017, DOI:10.3970/sdhm.2017.012.017

Abstract This paper describes the damage detection in framed structures due to the vertical support settlement and rotation of footing bases. The damage detection procedure proposed by Nobahari and Seyedpoor (2013) is used to detect the damage in the members of the frame. In the present study, instead of using the flexibility matrix (referred here as original flexibility matrix) method, the generalized flexibility matrix is used in the same algorithm and the results are compared. The algorithm uses flexibility matrix and strain energy concept to detect the damage in the members. The behaviour of the frame is discussed through changes observed… More >

Y. Zhang^1,2, Z.H. Xiang^1,3

CMC-Computers, Materials & Continua, Vol.26, No.1, pp. 19-36, 2011, DOI:10.3970/cmc.2011.026.019

Abstract Vibration based damage detection methods play an important role in the maintenance of beam structures such as bridges. However, most of them require the accurate measurement of structural mode shapes, which may not be easily satisfied in practice. Since the measurement of frequencies is more accurate than that of mode shapes, this paper proposes a frequency shift curve (FSC) method, based on the equivalence between the FSC due to auxiliary mass and the mode shape square, which has been demonstrated to be effective in structural damage detection. Two damage indices based on the FSC are developed, which are called the… More >

H.J. Xu¹, Z.H. Ding¹, Z.R. Lu^1,2, J.K. Liu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.111, No.4, pp. 335-355, 2016, DOI:10.3970/cmes.2016.111.335

Abstract An optimization approach based on Artificial Bee Colony (ABC) algorithm is proposed for structural local damage detection in this study. The objective function for the damage identification problem is established by structural parameters and modal assurance criteria (MAC). The ABC algorithm is presented to solve the certain objective function. Then the Tournament Selection Strategy and chaotic search mechanism is adopted to enhance global search ability of the certain algorithm. A coupled double-beam system is studied as numerical example to illustrate the correctness and efficiency of the propose method. The simulation results show that the modified ABC algorithm can identify the… More >

Q.W.Yang¹, J.K.Liu², C.H. Li³

CMES-Computer Modeling in Engineering & Sciences, Vol.91, No.4, pp. 313-335, 2013, DOI:10.3970/cmes.2013.091.313

Abstract A method based on best achievable flexibility change is presented in this paper to localize and quantify multiple damages in structures. The key process of the damage localization approach is the computation of the Euclidean distances between the measured flexibility change and the best achievable flexibility changes. The location of damage can be identified by searching for a value that is considerably smaller than others in these distances. For the multiple-damage case, a sequential damage localization approach is proposed to locate the damage sites one by one. With the suspected damaged elements determined, the flexibility sensitivity method is employed to… More >

Jiawei Xiang¹, Toshiro Matsumoto², Yanxue Wang³, Zhansi Jiang⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.81, No.3&4, pp. 269-294, 2011, DOI:10.3970/cmes.2011.081.269

Abstract Damages occurred in a structure will lead to changes in modal parameters (natural frequencies and modal shapes). The relationship between modal parameters and damage parameters (locations and depths) is very complicated. Single detection method using natural frequencies or modal shapes can not obtain robust damage detection results from the inevitably noise-contaminated modal parameters. To eliminate the complexity, a hybrid approach using both of wavelets on the interval (interval wavelets) method and wavelet finite element model-based method is proposed to detect damage locations and depths. To avoid the boundary distortion phenomenon, Interval wavelets are employed to analyze the finite-length modal shape… More >