serdar soyoz - Academia.edu (original) (raw)

Papers by serdar soyoz

Research paper thumbnail of Investigations on the elasticity modulus of stone masonry

Research paper thumbnail of Stochastic discontinuum analysis of unreinforced masonry walls: Lateral capacity and performance assessments

Research paper thumbnail of Long-term vibration-based monitoring and seismic performance assessment of a wind turbine

Journal of Civil Structural Health Monitoring

Research paper thumbnail of Modal identification of the first Bosporus bridge during hanger replacement

Structure and Infrastructure Engineering

Research paper thumbnail of Effects of preload deficiency on fatigue demands of wind turbine tower bolts

Journal of Constructional Steel Research

Research paper thumbnail of System Identification and Seismic Performance Assessment of a Stone Arch Bridge

Journal of Earthquake Engineering

Research paper thumbnail of In-Plane Seismic Response Analyses of a Historical Brick Masonry Building Using Equivalent Frame and 3D FEM Modeling Approaches

International Journal of Architectural Heritage

Research paper thumbnail of Quantifying the value of SHM for emergency management of bridges at-risk from seismic damage based on their performance indicators

Proceedings of the Joint COST TU1402 - COST TU1406 - IABSE WC1 Workshop: The Value of Structural Health Monitoring for the reliable Bridge Management

This paper proposes a framework for quantifying the value of information that can be derived from... more This paper proposes a framework for quantifying the value of information that can be derived from a structural health monitoring (SHM) system installed on a bridge which may sustain damage in the mainshock of an earthquake and further damage in an aftershock. The pre-posterior Bayesian analysis and the decision tree are the two main tools employed. The evolution of the damage state of the bridge with an SHM system is cast as a time-dependent, stochastic, discrete-state, observable dynamical system. An optimality problem is then formulated how to decide on the adoption of SHM and how to manage traffic and usage of a possibly damaged structure using the information from SHM. The objective function is the expected total cost or risk. The paper then discusses how to quantify bridge damage probability through stochastic seismic hazard and fragility analysis, how to update these probabilities using SHM technologies, and how to quantify bridge failure consequences.

Research paper thumbnail of System identification of Bogazici suspension bridge during hanger replacement

Research paper thumbnail of Quantifying the value of SHM for emergency management of bridges at-risk from seismic damage

This paper proposes a framework for quantifying the value of information that can be derived from... more This paper proposes a framework for quantifying the value of information that can be derived from a structural health monitoring (SHM) system installed on a bridge which may sustain damage in the mainshock of an earthquake and further damage in an aftershock. The pre-posterior Bayesian analysis and the decision tree are the two main tools employed. The evolution of the damage state of the bridge with an SHM system is cast as a time-dependent, stochastic, discrete-state, observable dynamical system. An optimality problem is then formulated how to decide on the adoption of SHM and how to manage traffic and usage of a possibly damaged structure using the information from SHM. The objective function is the expected total cost or risk. The paper then discusses how to quantify bridge damage probability through stochastic seismic hazard and fragility analysis, how to update these probabilities using SHM technologies, and how to quantify bridge failure consequences.

Research paper thumbnail of Effects of Soil-Structure Interaction and Base Isolation on Seismic Performance of Foundation Soils

ABSTRACT This study primarily focuses on structural induced liquefaction potential. Moreover, the... more ABSTRACT This study primarily focuses on structural induced liquefaction potential. Moreover, the effect of base isolation systems on both structural performance and liquefaction potential was studied including the soil-structure interaction effects. Four ...

Research paper thumbnail of Effect of identification on seismic performance assessment of an a tall building

Bulletin of Earthquake Engineering, 2015

Research paper thumbnail of C29. Effects of soil-structure interaction and base isolation on seismic performance of foundation soil

This study primarily focuses on structural induced liquefaction potential. Moreover, the effect o... more This study primarily focuses on structural induced liquefaction potential. Moreover, the effect of base isolation systems on both structural performance and liquefaction potential was studied including the soil-structure interaction effects. Four different types of structures and three different types of local sites were analyzed under two different input ground motions. It was mainly found that, depending on the structural type and for a certain depth, the liquefaction potential could be higher under the structure than the one in the free field. Besides decreasing the story drifts and shear forces in the structure, base isolation systems were very effective for decreasing liquefaction potential in the soil. It was also observed that soil-structure interaction leads to very significant changes in the response spectra.

Research paper thumbnail of Utilization of Seismic Response Measurement for Damage Detection and Capacity Estimation of Bridges

Research paper thumbnail of SHM-integrated bridge reliability estimation using multivariate stochastic processes

Earthquake Engineering & Structural Dynamics, 2014

ABSTRACT

Research paper thumbnail of Assessment of Platform Cognac Using Instrumentation Data

Proceedings of Offshore Technology Conference, 2009

Research paper thumbnail of Effects of higher wave harmonics on the response of monopile type offshore wind turbines

Research paper thumbnail of Damage detection based on damping analysis of ambient vibration data

Structural Control and Health Monitoring, 2008

Enabling an automated, remote and rapid detection of structural damage, sensor-based structural h... more Enabling an automated, remote and rapid detection of structural damage, sensor-based structural health monitoring is becoming a powerful tool for maintenance of civil engineering structures. In this study, a baseline-free, time-domain damage detection method was developed for concrete structures, which is based on analysis of nonlinear damping from measured structural vibration responses. The efficacy of the proposed method was demonstrated through a large-scale concrete bridge model subjected to different levels of seismic damage caused by shaking table tests. By applying the random decrement signature technique, the proposed method successfully identified, from its ambient vibration responses, nonlinear damping of the bridge associated with the seismic damage. The amount of the nonlinear damping increases as the seismic damage becomes more severe. This paper also compares the damage detection results with those obtained by stiffness-based methods, demonstrating a strong correlation between the increase in nonlinear damping and the decrease in structural stiffness associated with the increase in damage severity.

Research paper thumbnail of Instantaneous damage detection of bridge structures and experimental verification

Structural Control and Health Monitoring, 2008

An extended Kalman filtering (EKF) method was developed and applied to instantaneously identify e... more An extended Kalman filtering (EKF) method was developed and applied to instantaneously identify elemental stiffness values of a structure during damaging seismic events based on vibration measurement. This method is capable of dealing with nonlinear as well as linear structural responses. Identification of the structural elemental stiffness enables location as well as quantification of structural damage. The instantaneous stiffness values during an event can provide highly useful information for post-event capacity estimation. In this study, a large-scale shaking table test of a three-bent concrete bridge model was performed in order to verify the proposed damage detection method. The bridge model was shaken to different damage levels by a sequence of earthquake motions with increasing intensities. The elemental stiffness values of the structure were instantaneously identified in real time during the damaging earthquake excitations using the EKF method. The identified stiffness degradations and their locations agreed well with the structural damage observed by visual inspection and strain measurements. More importantly, the seismic response accelerations analytically simulated using the instantaneous stiffness values thus identified agreed well with the measured accelerations, demonstrating the accuracy of the identified stiffness. This study presents an experimental verification of a structural damage detection method using a realistic bridge model subjected to realistic seismic damage.

Research paper thumbnail of Large-Scale Shake Table Test Verification of Bridge Condition Assessment Methods

Journal of Structural Engineering, 2008

Methods that identify structural component stiffness degradation by pre-and postevent low amplitu... more Methods that identify structural component stiffness degradation by pre-and postevent low amplitude vibration measurements, based on a linear time-invariant ͑LTI͒ system model, are conceptually justified by examining the hysteresis loops the structural components experience in such vibrations. Two large-scale shake table experiments, one on a two-column reinforced concrete ͑RC͒ bridge bent specimen, and the other on a two-span three-bent RC bridge specimen were performed, in which specimens were subjected to earthquake ground motions with increasing amplitude and progressively damaged. In each of the damaged stages between two strong motions, low amplitude vibrations of the specimens were aroused, and the postevent component stiffness coefficients were identified by optimizing the parameters in a LTI model. The stiffness degradation identified is consistent with the experimental hysteresis, and could be quantitatively related to the capacity residual of the components.

Research paper thumbnail of Investigations on the elasticity modulus of stone masonry

Research paper thumbnail of Stochastic discontinuum analysis of unreinforced masonry walls: Lateral capacity and performance assessments

Research paper thumbnail of Long-term vibration-based monitoring and seismic performance assessment of a wind turbine

Journal of Civil Structural Health Monitoring

Research paper thumbnail of Modal identification of the first Bosporus bridge during hanger replacement

Structure and Infrastructure Engineering

Research paper thumbnail of Effects of preload deficiency on fatigue demands of wind turbine tower bolts

Journal of Constructional Steel Research

Research paper thumbnail of System Identification and Seismic Performance Assessment of a Stone Arch Bridge

Journal of Earthquake Engineering

Research paper thumbnail of In-Plane Seismic Response Analyses of a Historical Brick Masonry Building Using Equivalent Frame and 3D FEM Modeling Approaches

International Journal of Architectural Heritage

Research paper thumbnail of Quantifying the value of SHM for emergency management of bridges at-risk from seismic damage based on their performance indicators

Proceedings of the Joint COST TU1402 - COST TU1406 - IABSE WC1 Workshop: The Value of Structural Health Monitoring for the reliable Bridge Management

This paper proposes a framework for quantifying the value of information that can be derived from... more This paper proposes a framework for quantifying the value of information that can be derived from a structural health monitoring (SHM) system installed on a bridge which may sustain damage in the mainshock of an earthquake and further damage in an aftershock. The pre-posterior Bayesian analysis and the decision tree are the two main tools employed. The evolution of the damage state of the bridge with an SHM system is cast as a time-dependent, stochastic, discrete-state, observable dynamical system. An optimality problem is then formulated how to decide on the adoption of SHM and how to manage traffic and usage of a possibly damaged structure using the information from SHM. The objective function is the expected total cost or risk. The paper then discusses how to quantify bridge damage probability through stochastic seismic hazard and fragility analysis, how to update these probabilities using SHM technologies, and how to quantify bridge failure consequences.

Research paper thumbnail of System identification of Bogazici suspension bridge during hanger replacement

Research paper thumbnail of Quantifying the value of SHM for emergency management of bridges at-risk from seismic damage

This paper proposes a framework for quantifying the value of information that can be derived from... more This paper proposes a framework for quantifying the value of information that can be derived from a structural health monitoring (SHM) system installed on a bridge which may sustain damage in the mainshock of an earthquake and further damage in an aftershock. The pre-posterior Bayesian analysis and the decision tree are the two main tools employed. The evolution of the damage state of the bridge with an SHM system is cast as a time-dependent, stochastic, discrete-state, observable dynamical system. An optimality problem is then formulated how to decide on the adoption of SHM and how to manage traffic and usage of a possibly damaged structure using the information from SHM. The objective function is the expected total cost or risk. The paper then discusses how to quantify bridge damage probability through stochastic seismic hazard and fragility analysis, how to update these probabilities using SHM technologies, and how to quantify bridge failure consequences.

Research paper thumbnail of Effects of Soil-Structure Interaction and Base Isolation on Seismic Performance of Foundation Soils

ABSTRACT This study primarily focuses on structural induced liquefaction potential. Moreover, the... more ABSTRACT This study primarily focuses on structural induced liquefaction potential. Moreover, the effect of base isolation systems on both structural performance and liquefaction potential was studied including the soil-structure interaction effects. Four ...

Research paper thumbnail of Effect of identification on seismic performance assessment of an a tall building

Bulletin of Earthquake Engineering, 2015

Research paper thumbnail of C29. Effects of soil-structure interaction and base isolation on seismic performance of foundation soil

This study primarily focuses on structural induced liquefaction potential. Moreover, the effect o... more This study primarily focuses on structural induced liquefaction potential. Moreover, the effect of base isolation systems on both structural performance and liquefaction potential was studied including the soil-structure interaction effects. Four different types of structures and three different types of local sites were analyzed under two different input ground motions. It was mainly found that, depending on the structural type and for a certain depth, the liquefaction potential could be higher under the structure than the one in the free field. Besides decreasing the story drifts and shear forces in the structure, base isolation systems were very effective for decreasing liquefaction potential in the soil. It was also observed that soil-structure interaction leads to very significant changes in the response spectra.

Research paper thumbnail of Utilization of Seismic Response Measurement for Damage Detection and Capacity Estimation of Bridges

Research paper thumbnail of SHM-integrated bridge reliability estimation using multivariate stochastic processes

Earthquake Engineering & Structural Dynamics, 2014

ABSTRACT

Research paper thumbnail of Assessment of Platform Cognac Using Instrumentation Data

Proceedings of Offshore Technology Conference, 2009

Research paper thumbnail of Effects of higher wave harmonics on the response of monopile type offshore wind turbines

Research paper thumbnail of Damage detection based on damping analysis of ambient vibration data

Structural Control and Health Monitoring, 2008

Enabling an automated, remote and rapid detection of structural damage, sensor-based structural h... more Enabling an automated, remote and rapid detection of structural damage, sensor-based structural health monitoring is becoming a powerful tool for maintenance of civil engineering structures. In this study, a baseline-free, time-domain damage detection method was developed for concrete structures, which is based on analysis of nonlinear damping from measured structural vibration responses. The efficacy of the proposed method was demonstrated through a large-scale concrete bridge model subjected to different levels of seismic damage caused by shaking table tests. By applying the random decrement signature technique, the proposed method successfully identified, from its ambient vibration responses, nonlinear damping of the bridge associated with the seismic damage. The amount of the nonlinear damping increases as the seismic damage becomes more severe. This paper also compares the damage detection results with those obtained by stiffness-based methods, demonstrating a strong correlation between the increase in nonlinear damping and the decrease in structural stiffness associated with the increase in damage severity.

Research paper thumbnail of Instantaneous damage detection of bridge structures and experimental verification

Structural Control and Health Monitoring, 2008

An extended Kalman filtering (EKF) method was developed and applied to instantaneously identify e... more An extended Kalman filtering (EKF) method was developed and applied to instantaneously identify elemental stiffness values of a structure during damaging seismic events based on vibration measurement. This method is capable of dealing with nonlinear as well as linear structural responses. Identification of the structural elemental stiffness enables location as well as quantification of structural damage. The instantaneous stiffness values during an event can provide highly useful information for post-event capacity estimation. In this study, a large-scale shaking table test of a three-bent concrete bridge model was performed in order to verify the proposed damage detection method. The bridge model was shaken to different damage levels by a sequence of earthquake motions with increasing intensities. The elemental stiffness values of the structure were instantaneously identified in real time during the damaging earthquake excitations using the EKF method. The identified stiffness degradations and their locations agreed well with the structural damage observed by visual inspection and strain measurements. More importantly, the seismic response accelerations analytically simulated using the instantaneous stiffness values thus identified agreed well with the measured accelerations, demonstrating the accuracy of the identified stiffness. This study presents an experimental verification of a structural damage detection method using a realistic bridge model subjected to realistic seismic damage.

Research paper thumbnail of Large-Scale Shake Table Test Verification of Bridge Condition Assessment Methods

Journal of Structural Engineering, 2008

Methods that identify structural component stiffness degradation by pre-and postevent low amplitu... more Methods that identify structural component stiffness degradation by pre-and postevent low amplitude vibration measurements, based on a linear time-invariant ͑LTI͒ system model, are conceptually justified by examining the hysteresis loops the structural components experience in such vibrations. Two large-scale shake table experiments, one on a two-column reinforced concrete ͑RC͒ bridge bent specimen, and the other on a two-span three-bent RC bridge specimen were performed, in which specimens were subjected to earthquake ground motions with increasing amplitude and progressively damaged. In each of the damaged stages between two strong motions, low amplitude vibrations of the specimens were aroused, and the postevent component stiffness coefficients were identified by optimizing the parameters in a LTI model. The stiffness degradation identified is consistent with the experimental hysteresis, and could be quantitatively related to the capacity residual of the components.