Mr. Reza Baghaei-Naeini Profile

Reza Baghaei-Naeini

SPIE Involvement:

Author

Publications (3)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 20 April 2011 Paper

Utilization of strong motion data for damage assessment of reinforced concrete bridges

Reza Baghaei, Maria Feng

Proceedings Volume 7983, 79832P (2011) https://doi.org/10.1117/12.880727

KEYWORDS: Bridges, Earthquakes, Time-frequency analysis, Optimization (mathematics), Genetic algorithms, Data modeling, Stochastic processes, Mathematical modeling, Error analysis, Calibration

Read Abstract +

This study investigates the performance of a vibration-based technique for damage assessment of reinforced concrete bridges from non-stationary and incomplete acceleration response measurements during high amplitude earthquakes. The proposed damage assessment technique is targeted to be used in the aftermath of a major earthquake event to rapidly and remotely assess the functionality status of the bridge and identify potential hazards to the public safety. As the first step of the procedure, time-frequency representation of the response of the bridge is achieved by applying stochastic subspace system identification technique to successive and overlapping windows of the response measurements. The timefrequency representation is then used to identify the longest ending segment of the response with relatively stable modal properties. Post-earthquake experimental modal properties of the bridge are subsequently extracted from the identified stable portion of the response. These properties are used to estimate the amount of degradation in stiffness of the structural elements through an optimization-based finite element model updating technique. The Genetic Algorithm optimization technique is used to update the stiffness properties of the structural elements by minimizing the error between analytical and experimental modal properties of the bridge. The proposed damage assessment procedure is applied to experimental data from a large-scale shake table test during which a quarter-scale model of a reinforced concrete bridge was subjected to a series of earthquake and low-amplitude white noise base excitations. The meaningful agreement between the stiffness correction factors identified from both types of motions at the same damage state of the bridge demonstrates that the proposed procedure can effectively be applied for post-earthquake damage assessment of the bridges from nonlinear responses during high amplitude earthquakes.

Proceedings Article | 20 April 2011 Paper

Residual capacity estimation of bridges using structural health monitoring data

Reza Baghaei, Maria Feng, Marco Torbol

Proceedings Volume 7983, 79833I (2011) https://doi.org/10.1117/12.880728

KEYWORDS: Bridges, Earthquakes, Motion models, Data modeling, Databases, Structural health monitoring, Nonlinear response, Structural engineering, Analytical research, Modal analysis

Read Abstract +

In this study, a vibration-based procedure for residual capacity estimation of bridges after damaging earthquake events is proposed. The procedure starts with estimation of collapse capacity of the intact bridge using incremental dynamic analysis (IDA) curves. The collapse capacity is defined as the median intensity level of the earthquakes that cause global or local collapse within the structure. A database of post-earthquake modal properties is created by calculating the analytical modal properties of the bridge after each nonlinear response history analysis performed for generation IDA curves. After the damaging event, experimental modal properties of the bridge are identified from vibration measurements of the bridge. These properties along with the modal properties database are used to find ground motionintensity pairs that can drive nonlinear FE model of the structure to the current damage state of the bridge. The IDA curves corresponding to the damaged FE model of the bridge are subsequently used to estimate amount of loss in collapse capacity of the damaged structure. Estimated loss in capacity of the bridge besides the bridge-site-specific seismic hazard curves are used to update the functionality status of the bridge. Proposed procedure is applied to experimental data from a large-scale shake table test on a quarter-scale model of a short-span reinforced concrete bridge. The bridge was subjected to a series of earthquake ground motions introducing progressive seismic damage to the bridge which finally led to the failure of one of the bents. Residual collapse capacity and functionality status of the bridge are updated at different stages of the experiment using the proposed procedure.

Proceedings Article | 9 April 2010 Paper

Damage assessment of the bridge structures using a hybrid optimization strategy

Reza Baghaei, Maria Feng

Proceedings Volume 7649, 76491N (2010) https://doi.org/10.1117/12.848855

KEYWORDS: Bridges, Data modeling, Optimization (mathematics), Signal to noise ratio, Earthquakes, Calibration, Matrices, Motion models, Error analysis, Interference (communication)

Read Abstract +

Vibration based damage assessment of structures can be formulated as an optimization problem with the objective of minimizing the error between the measured and simulated responses of the structure by updating analytical model parameters. In this study, genetic algorithm (GA) and pattern search technique are combined in a hybrid optimization framework for finite element (FE) model updating using two objective functions defined in time and modal domains. The proposed model updating techniques have been applied to experimental data recorded during a shake table test on a quarter-scale model of a two span reinforced concrete bridge. The bridge was subjected to a series of seismic base excitations with increasing intensities introducing progressive real damage to the structure. Bridge responses to intermediate low amplitude white noise excitations are used for the purpose of modal identification and damage assessment. The FE model parameters are updated at different stages of the experiment. This study shows that damage throughout the structure can be accurately and consistently detected, located and quantified using the proposed model updating techniques.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years