Vibration-Based Damage Detection and Seismic Performance Assessment of Bridges

2015 ◽  
Vol 31 (1) ◽  
pp. 137-157 ◽  
Author(s):  
Ekin Özer ◽  
Serdar Soyöz
Keyword(s):  
Finite Element ◽  
Damage Detection ◽  
Structural Damage ◽  
Fragility Curves ◽  
Reliability Estimation ◽  
Concrete Bridge ◽  
Finite Element Models ◽  
Seismic Performance Assessment ◽  
Reinforced Concrete Bridge ◽  
The Difference

This paper proposes a reliability estimation methodology which utilizes system identification results obtained from vibration measurements. A series of earthquake and white noise excitations are imposed to a three-bent reinforced concrete bridge by three-shaking tables, simultaneously. Progressive structural damage is measured and observed, in accordance with increasing intensities of damaging events. Response measurements are obtained by accelerometers located on the deck and the columns of the bridge. Finite element models for non-updated and updated cases were obtained with and without considering acceleration measurements, respectively. Afterwards, damage detection and reliability estimation were carried out for these two cases using fragility curves. Consequently, it is shown that fragility curves of updated models significantly differ from fragility curves of non-updated models. The distinction stems from the difference between stiffness and especially damping parameters of updated and non-updated models. Such difference becomes more prominent at the extreme levels of damage.

scholarly journals Empirical method for structural damage location using dynamic analysis

2020 ◽  
Vol 13 (1) ◽  
pp. 19-31
Author(s):  
R. L. SILVA ◽  
L. M. TRAUTWEIN ◽  
C. S. BARBOSA ◽  
L. C. ALMEIDA ◽  
G. H. SIQUEIRA
Keyword(s):  
Finite Element ◽  
Structural Damage ◽  
Empirical Method ◽  
Finite Element Models ◽  
Simply Supported ◽  
Damage Location ◽  
Acceleration Amplitude ◽  
Modal Curvature ◽  
The Difference ◽  
Rubber Bearings

Abstract This paper presents the use of numerical model techniques for identification and damage location adopting the Modal Curvature Difference (MCD) method as reference for the analysis of a simply supported concrete structure. Then, an empirical formulation to detect damages in this structure is proposed. In this method, called Acceleration Summation Difference (ASD), the difference of acceleration amplitude between intact and damaged structures are calculated for concrete plates simply supported on rubber bearings. During the analyses, the finite element models were developed using SAP2000® software. The results obtained depicted that it is possible to determine the approximate position of one or more damages in the structure, with some restrictions, and the proposed ASD method presented good correlation to localize the position of single or multiple damages.

Photogrammetry-based structural damage detection by tracking a visible laser line

2019 ◽  
Vol 19 (1) ◽  
pp. 322-336 ◽  
Author(s):  
Yongfeng Xu
Keyword(s):  
Finite Element ◽  
Damage Detection ◽  
Structural Damage ◽  
Detection Method ◽  
Element Model ◽  
Target Line ◽  
Laser Line ◽  
Modal Parameters ◽  
Structural Damage Detection ◽  
Visible Laser

Research works on photogrammetry have received tremendous attention in the past few decades. One advantage of photogrammetry is that it can measure displacement and deformation of a structure in a fully non-contact, full-field manner. As a non-destructive evaluation method, photogrammetry can be used to detect structural damage by identifying local anomalies in measured deformation of a structure. Numerous methods have been proposed to measure deformations by tracking exterior features of structures, assuming that the features can be consistently identified and tracked on sequences of digital images captured by cameras. Such feature-tracking methods can fail if the features do not exist on captured images. One feasible solution to the potential failure is to artificially add exterior features to structures. However, painting and mounting such features can introduce unwanted permanent surficial modifications, mass loads, and stiffness changes to structures. In this article, a photogrammetry-based structural damage detection method is developed, where a visible laser line is projected to a surface of a structure, serving as an exterior feature to be tracked; the projected laser line is massless and its existence is temporary. A laser-line-tracking technique is proposed to track the projected laser line on captured digital images. Modal parameters of a target line corresponding to the projected laser line can be estimated by conducting experimental modal analysis. By identifying anomalies in curvature mode shapes of the target line and mapping the anomalies to the projected laser line, structural damage can be detected with identified positions and sizes. An experimental investigation of the damage detection method was conducted on a damaged beam. Modal parameters of a target line corresponding to a projected laser line were estimated, which compared well with those from a finite element model of the damaged beam. Experimental damage detection results were validated by numerical ones from the finite element model.

Comparison of Two Approaches to Model Cure-Induced Microcracking in Three-Dimensional Woven Composites

2012 ◽  
Author(s):  
Igor Tsukrov ◽  
Michael Giovinazzo ◽  
Kateryna Vyshenska ◽  
Harun Bayraktar ◽  
Jon Goering ◽  
...  
Keyword(s):  
Finite Element ◽  
Residual Stresses ◽  
Volume Fraction ◽  
Three Dimensional ◽  
Woven Composites ◽  
Finite Element Models ◽  
The Matrix ◽  
3D Woven Composites ◽  
The Difference ◽  
Resin Curing

Finite element models of 3D woven composites are developed to predict possible microcracking of the matrix during curing. A specific ply-to-ply weave architecture for carbon fiber reinforced epoxy is chosen as a benchmark case. Two approaches to defining the geometry of reinforcement are considered. One is based on the nominal description of composite, and the second involves fabric mechanics simulations. Finite element models utilizing these approaches are used to calculate the overall elastic properties of the composite, and predict residual stresses due to resin curing. It is shown that for the same volume fraction of reinforcement, the difference in the predicted overall in-plane stiffness is on the order of 10%. Numerical model utilizing the fabric mechanics simulations predicts lower level of residual stresses due to curing, as compared to nominal geometry models.

Sign in / Sign up

Export Citation Format

Share Document