New Damage Detection Method Based on Support Reaction and Mid-Span Displacement for Simply Supported Bridges

Capabilities to locate damage, and applicability to simply supported bridges are considered as basic characteristics of the method to be investigated in this paper. A new method which employs support reaction and mid-span displacement as indicators is presented to detect a certain type of damage. Unlike the existing study, this work proposes the direct relationship between the change in local mass caused by damage and the measured support reaction and mid-span displacement values. With the cooperation of inspection means, this method is capable of successfully identifying the location of local potential damage. The feasibility of this method is demonstrated by numerical simulation and model experiment.

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Structural Damage Detection Depending on Curvature Matrix of Change in Flexibility

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.389 ◽

2011 ◽

Vol 255-260 ◽

pp. 389-393

Author(s):

Yong Mei Li ◽

Bin Zhou ◽

Xi Yuan Zhou ◽

Guo Fu Sun ◽

Bo Yan Yang

Keyword(s):

Numerical Simulation ◽

Damage Detection ◽

Cantilever Beam ◽

Lower Order ◽

Structural Damage ◽

Structural Damage Detection ◽

Principal Diagonal ◽

Simply Supported ◽

Damage Location ◽

Difference Calculation

Flexibility is more sensitive to structural damage than frequency or mode. Curvature matrix of change in flexibility is presented as a new index of nondestructive damage detection, which is derived from change in structural flexibilities calculated from before damaging and after damaging by means of difference calculation twice, firstly to columns, and then to rows. Therefore a new indicator called as δ Flexibility Curvature Matrix Diagonal (δFCMD) is constructed from the principal diagonal elements based on curvature matrix of change in flexibility. The numerical simulation examples indicate that the damage location and severity in structures, with single damage, multiple ones, slight ones and ones at the supports, can be detected efficiently for a cantilever beam, a fixed supported beam, a simply supported beams and so on by the indicator of δFCMD depending on only a few of lower order modes.

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Damage Detection for Simply Supported Beams Using Mid-Span Displacement Indicator

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.29-32.1532 ◽

2010 ◽

Vol 29-32 ◽

pp. 1532-1536

Author(s):

S.J. Zhang ◽

Z.J. Ma

Keyword(s):

Damage Detection ◽

Direct Relationship ◽

Cost Effective ◽

Small Region ◽

The Novel ◽

New Approach ◽

Simply Supported ◽

Detection Approach ◽

Damaged Beams ◽

Local Stiffness

This paper investigates the detection of damage for simply supported beams to ensure their safety. Based on the analysis of possible kinds of damage may occur, this paper presents a new approach which relies on the fact that any change in local stiffness caused by damage can be reflected by the change of mid-span displacement between the intact and damaged beams. Direct relationship between the change in local stiffness and the measured mid-span displacement values is developed. This approach can identify the geometric locations of damage and then inspection means are used as a complement to find the real damage phenomena within the obtained small region. A numerical example is given to illustrate the feasibility and the effectiveness of the approach. The novel content offered by authors provides a simple, convenient, cost-effective, and nondestructive damage detection approach for simply supported beams.

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Mode Shape-Based Damage Detection Method (MSDI): Experimental Validation

Applied Sciences ◽

10.3390/app11104589 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4589

Author(s):

Ivan Duvnjak ◽

Domagoj Damjanović ◽

Marko Bartolac ◽

Ana Skender

Keyword(s):

Boundary Conditions ◽

Damage Detection ◽

Mode Shape ◽

Experimental Validation ◽

Detection Method ◽

Dynamic Properties ◽

Damage Index ◽

Main Principle ◽

The Difference ◽

Different Levels

The main principle of vibration-based damage detection in structures is to interpret the changes in dynamic properties of the structure as indicators of damage. In this study, the mode shape damage index (MSDI) method was used to identify discrete damages in plate-like structures. This damage index is based on the difference between modified modal displacements in the undamaged and damaged state of the structure. In order to assess the advantages and limitations of the proposed algorithm, we performed experimental modal analysis on a reinforced concrete (RC) plate under 10 different damage cases. The MSDI values were calculated through considering single and/or multiple damage locations, different levels of damage, and boundary conditions. The experimental results confirmed that the MSDI method can be used to detect the existence of damage, identify single and/or multiple damage locations, and estimate damage severity in the case of single discrete damage.

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Elimination of outlier measurements for damage detection of structures under changing environmental conditions

Structural Health Monitoring ◽

10.1177/1475921721998476 ◽

2021 ◽

pp. 147592172199847

Author(s):

William Soo Lon Wah ◽

Yining Xia

Keyword(s):

Damage Detection ◽

Multiple Regression ◽

Natural Frequencies ◽

Detection Method ◽

Detection Methods ◽

Structure Model ◽

Bridge Structure ◽

Beam Structure ◽

Dependent Variables ◽

The Difference

Damage detection methods developed in the literature are affected by the presence of outlier measurements. These measurements can prevent small levels of damage to be detected. Therefore, a method to eliminate the effects of outlier measurements is proposed in this article. The method uses the difference in fits to examine how deleting an observation affects the predicted value of a model. This allows the observations that have a large influence on the model created, to be identified. These observations are the outlier measurements and they are eliminated from the database before the application of damage detection methods. Eliminating the outliers before the application of damage detection methods allows the normal procedures to detect damage, to be implemented. A multiple-regression-based damage detection method, which uses the natural frequencies as both the independent and dependent variables, is also developed in this article. A beam structure model and an experimental wooden bridge structure are analysed using the multiple-regression-based damage detection method with and without the application of the method proposed to eliminate the effects of outliers. The results obtained demonstrate that smaller levels of damage can be detected when the effects of outlier measurements are eliminated using the method proposed in this article.

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Damage detection method for shear buildings using the changes in the first mode shape slopes

Computers & Structures ◽

10.1016/j.compstruc.2011.02.014 ◽

2011 ◽

Vol 89 (9-10) ◽

pp. 733-743 ◽

Cited By ~ 44

Author(s):

Hongping Zhu ◽

Lin Li ◽

Xiao-Qiao He

Keyword(s):

Damage Detection ◽

Mode Shape ◽

Detection Method ◽

Shear Buildings

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Study on Damage Detection of Bridge Based on Wavelet Multi-Scale Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.639-640.1010 ◽

2013 ◽

Vol 639-640 ◽

pp. 1010-1014 ◽

Cited By ~ 1

Author(s):

Ke Ding ◽

Ting Peng Chen

Keyword(s):

Wavelet Transform ◽

Damage Detection ◽

Detection Method ◽

Mode Shapes ◽

Scale Analysis ◽

Multi Scale ◽

Damage Location ◽

Transform Coefficients ◽

Beam Bridge ◽

Multi Scale Analysis

The damage detection method based on wavelet multi-scale analysis is presented in the paper. The damage location can be identified by analyzing the multi-scale wavelet transform coefficients of curvatures of mode shapes. The extreme value of wavelet transform coefficients indicates the damage location. But it is difficult to detect the location of defect if the defect is near to the equilibrium position of vibration. In order to solve this problem, we put forward a method which is to add the wavelet transform coefficients of multi modals together. The method can effectively overcome the above problem. Three damage situations of simply supported beam bridge are discussed in the paper. The results show that the peaks of wavelet transform coefficients indicate the damage location of structural. It is possible to pinpoint the damage location based on wavelet multi-scale analysis on curvatures of mode shapes.

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