The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Joaquim Figueiras - One of the best experts on this subject based on the ideXlab platform.
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construction assessment and long term prediction of prestressed concrete bridges based on Monitoring data
Engineering Structures, 2013Co-Authors: Helder Sousa, Joao Bento, Joaquim FigueirasAbstract:Abstract The Long-Term assessment of large civil infrastructures such as prestressed concrete bridges is a challenging task. The real time history related to the phased construction, the influence of the adopted constructive method, the characterization of the employed concrete and the environmental conditions are crucial aspects for accurate predictions based on Finite Element Models. Data from Long-Term Monitoring Systems have been used to improve the quality of those predictions, namely to validate the design assumptions, to calibrate the structural model, and to update the safety coefficients. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 1700 m long viaduct, which was erected using a movable scaffolding System. A Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. Based on these measurements, this work presents the analysis strategy adopted to compute the Long-Term behaviour based on a Finite Element Model. A detailed scanning of all information with relevance for the viaduct behaviour was performed. A full discussion concerning the real Long-Term behaviour is made, focusing the differences between the measurements and the results obtained with the numerical model, namely the trends due to shrinkage and creep and the variations due to the temperature. Finally, concerning to the viaduct lifetime, the predicted values for the measured parameters are updated, since the predictions based on the European standard rules presents significant bias to be used as reference values regarding the viaduct surveillance.
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construction assessment and long term prediction of prestressed concrete bridges based on Monitoring data
Engineering Structures, 2013Co-Authors: Helder Sousa, Joao Bento, Joaquim FigueirasAbstract:Abstract The Long-Term assessment of large civil infrastructures such as prestressed concrete bridges is a challenging task. The real time history related to the phased construction, the influence of the adopted constructive method, the characterization of the employed concrete and the environmental conditions are crucial aspects for accurate predictions based on Finite Element Models. Data from Long-Term Monitoring Systems have been used to improve the quality of those predictions, namely to validate the design assumptions, to calibrate the structural model, and to update the safety coefficients. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 1700 m long viaduct, which was erected using a movable scaffolding System. A Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. Based on these measurements, this work presents the analysis strategy adopted to compute the Long-Term behaviour based on a Finite Element Model. A detailed scanning of all information with relevance for the viaduct behaviour was performed. A full discussion concerning the real Long-Term behaviour is made, focusing the differences between the measurements and the results obtained with the numerical model, namely the trends due to shrinkage and creep and the variations due to the temperature. Finally, concerning to the viaduct lifetime, the predicted values for the measured parameters are updated, since the predictions based on the European standard rules presents significant bias to be used as reference values regarding the viaduct surveillance.
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Long-Term Monitoring and assessment of a precast continuous viaduct
Structure and Infrastructure Engineering, 2013Co-Authors: Helder Sousa, Joao Bento, Carlos Sousa, Afonso Serra Neves, Joaquim FigueirasAbstract:Precast girders have recently been widely employed in the construction of bridges and viaducts. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 9160 m long south approach viaduct, which was built with precast girders made continuous in situ. Given the relevance of this construction, a Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. The observed parameters were concrete strains and temperatures, deck rotations, joint displacements, accelerations and also environment temperature and relative humidity. The work presents the precast structure, the Monitoring System and the appraisal of a statistical procedure for the Long-Term assessment of the structural behaviour. This procedure is based on prediction models, which establish the normal correlation patterns between environmental and material parameters (such as concrete temperature and shrinkage strains), and the observed structural response in terms of strains, r...
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design and implementation of a Monitoring System applied to a long span prestressed concrete bridge
Structural Concrete, 2011Co-Authors: Helder Sousa, Carlos Felix, Joao Bento, Joaquim FigueirasAbstract:Currently, Long-Term Monitoring Systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the Long-Term Monitoring System installed on the new Leziria Bridge over the River Tagus in Portugal. The System was developed to control some aspects of the construction process and to survey the service life of the structure. A set of structural, durability and environmental parameters defining the bridge condition are remotely assessed in real-time via a fibreoptic network. Aspects such as architecture, installation and functionality of the Monitoring System are discussed and the innovative aspects of the implementation are highlighted. In this context, the main goal of this work is to present the Long-Term Monitoring System of Leziria Bridge, sharing the experiences, the solutions and the procedures adopted, given their potential usefulness in the implementation of similar projects. Copyright © 2011 Ernst & Sohn Verlag fur Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.
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design and implementation of a Monitoring System applied to a long span prestressed concrete bridge
Structural Concrete, 2011Co-Authors: Helder Sousa, Carlos Felix, Joao Bento, Joaquim FigueirasAbstract:Currently, Long-Term Monitoring Systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the Long-Term Monitoring System installed on the new Leziria Bridge over the River Tagus in Portugal. The System was developed to control some aspects of the construction process and to survey the service life of the structure. A set of structural, durability and environmental parameters defining the bridge condition are remotely assessed in real-time via a fibreoptic network. Aspects such as architecture, installation and functionality of the Monitoring System are discussed and the innovative aspects of the implementation are highlighted. In this context, the main goal of this work is to present the Long-Term Monitoring System of Leziria Bridge, sharing the experiences, the solutions and the procedures adopted, given their potential usefulness in the implementation of similar projects. Copyright © 2011 Ernst & Sohn Verlag fur Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.
Helder Sousa - One of the best experts on this subject based on the ideXlab platform.
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construction assessment and long term prediction of prestressed concrete bridges based on Monitoring data
Engineering Structures, 2013Co-Authors: Helder Sousa, Joao Bento, Joaquim FigueirasAbstract:Abstract The Long-Term assessment of large civil infrastructures such as prestressed concrete bridges is a challenging task. The real time history related to the phased construction, the influence of the adopted constructive method, the characterization of the employed concrete and the environmental conditions are crucial aspects for accurate predictions based on Finite Element Models. Data from Long-Term Monitoring Systems have been used to improve the quality of those predictions, namely to validate the design assumptions, to calibrate the structural model, and to update the safety coefficients. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 1700 m long viaduct, which was erected using a movable scaffolding System. A Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. Based on these measurements, this work presents the analysis strategy adopted to compute the Long-Term behaviour based on a Finite Element Model. A detailed scanning of all information with relevance for the viaduct behaviour was performed. A full discussion concerning the real Long-Term behaviour is made, focusing the differences between the measurements and the results obtained with the numerical model, namely the trends due to shrinkage and creep and the variations due to the temperature. Finally, concerning to the viaduct lifetime, the predicted values for the measured parameters are updated, since the predictions based on the European standard rules presents significant bias to be used as reference values regarding the viaduct surveillance.
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construction assessment and long term prediction of prestressed concrete bridges based on Monitoring data
Engineering Structures, 2013Co-Authors: Helder Sousa, Joao Bento, Joaquim FigueirasAbstract:Abstract The Long-Term assessment of large civil infrastructures such as prestressed concrete bridges is a challenging task. The real time history related to the phased construction, the influence of the adopted constructive method, the characterization of the employed concrete and the environmental conditions are crucial aspects for accurate predictions based on Finite Element Models. Data from Long-Term Monitoring Systems have been used to improve the quality of those predictions, namely to validate the design assumptions, to calibrate the structural model, and to update the safety coefficients. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 1700 m long viaduct, which was erected using a movable scaffolding System. A Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. Based on these measurements, this work presents the analysis strategy adopted to compute the Long-Term behaviour based on a Finite Element Model. A detailed scanning of all information with relevance for the viaduct behaviour was performed. A full discussion concerning the real Long-Term behaviour is made, focusing the differences between the measurements and the results obtained with the numerical model, namely the trends due to shrinkage and creep and the variations due to the temperature. Finally, concerning to the viaduct lifetime, the predicted values for the measured parameters are updated, since the predictions based on the European standard rules presents significant bias to be used as reference values regarding the viaduct surveillance.
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Long-Term Monitoring and assessment of a precast continuous viaduct
Structure and Infrastructure Engineering, 2013Co-Authors: Helder Sousa, Joao Bento, Carlos Sousa, Afonso Serra Neves, Joaquim FigueirasAbstract:Precast girders have recently been widely employed in the construction of bridges and viaducts. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 9160 m long south approach viaduct, which was built with precast girders made continuous in situ. Given the relevance of this construction, a Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. The observed parameters were concrete strains and temperatures, deck rotations, joint displacements, accelerations and also environment temperature and relative humidity. The work presents the precast structure, the Monitoring System and the appraisal of a statistical procedure for the Long-Term assessment of the structural behaviour. This procedure is based on prediction models, which establish the normal correlation patterns between environmental and material parameters (such as concrete temperature and shrinkage strains), and the observed structural response in terms of strains, r...
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design and implementation of a Monitoring System applied to a long span prestressed concrete bridge
Structural Concrete, 2011Co-Authors: Helder Sousa, Carlos Felix, Joao Bento, Joaquim FigueirasAbstract:Currently, Long-Term Monitoring Systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the Long-Term Monitoring System installed on the new Leziria Bridge over the River Tagus in Portugal. The System was developed to control some aspects of the construction process and to survey the service life of the structure. A set of structural, durability and environmental parameters defining the bridge condition are remotely assessed in real-time via a fibreoptic network. Aspects such as architecture, installation and functionality of the Monitoring System are discussed and the innovative aspects of the implementation are highlighted. In this context, the main goal of this work is to present the Long-Term Monitoring System of Leziria Bridge, sharing the experiences, the solutions and the procedures adopted, given their potential usefulness in the implementation of similar projects. Copyright © 2011 Ernst & Sohn Verlag fur Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.
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design and implementation of a Monitoring System applied to a long span prestressed concrete bridge
Structural Concrete, 2011Co-Authors: Helder Sousa, Carlos Felix, Joao Bento, Joaquim FigueirasAbstract:Currently, Long-Term Monitoring Systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the Long-Term Monitoring System installed on the new Leziria Bridge over the River Tagus in Portugal. The System was developed to control some aspects of the construction process and to survey the service life of the structure. A set of structural, durability and environmental parameters defining the bridge condition are remotely assessed in real-time via a fibreoptic network. Aspects such as architecture, installation and functionality of the Monitoring System are discussed and the innovative aspects of the implementation are highlighted. In this context, the main goal of this work is to present the Long-Term Monitoring System of Leziria Bridge, sharing the experiences, the solutions and the procedures adopted, given their potential usefulness in the implementation of similar projects. Copyright © 2011 Ernst & Sohn Verlag fur Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.
Qing Fei Gao - One of the best experts on this subject based on the ideXlab platform.
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Temperature Effects on Strains of a Continuous Box-Girder Bridge with a Long-Term Monitoring System
Structural Health Monitoring 2015, 2015Co-Authors: Chuang Chen, Mosbeh R. Kaloop, Zong Lin Wang, Qing Fei GaoAbstract:Daily and seasonal temperature-induced strains of a prestressed concrete (PSC) continuous box-girder bridge were presented. Strain measurement, using fiber Bragg grating sensors, constitutes a crucial component of the System in the Monitoring of the bridge’s key sections response in order to evaluate its structural behavior under environmental and traffic loads. This study was carried out to determine the effects of daily and seasonal temperature variations on the bridge deformation. Moreover, the insolation generates vertical temperature gradients in the box-girder cross sections, which are responsible for the strain differences in the plates and for its variation in the webs along their heights. In addition, in order to identify the qualitative and quantitative relation between the temperature and the strains on the cross sections, the Monitoring temperature measurements of the bridge during the construction were applied. The results show that: (1) the seasonal temperature variation can significantly influence the strain of concrete bridges in cold regions; (2) in the high temperature periods the strain of the box-girder top plates experiences the largest variation, whereas for the bottom plates deformation the low temperature periods have a higher impact; (3) the daily and seasonal strain variations induced by uniform temperature reveal an inconsistent tendency for mid-span cross sections. doi: 10.12783/SHM2015/104
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Design of a Long-Term Monitoring System for a PSC Continuous Box- girder Bridge
Key Engineering Materials, 2014Co-Authors: Chuang Chen, R. Kaloop Mosbeh, Zong Lin Wang, Qing Fei Gao, Jun Fei ZhongAbstract:Structural Health Monitoring is becoming an increasingly common tool to obtain the Long-Term performance of infrastructures and buildings. Many structural health Monitoring Systems were developed and applied to different bridges in the world. However, very little is known on the applications in extreme cold environment. Fu Sui Bridge, a 1070 m variable cross-section continuous box-girder bridge, is located in the coldest province -- Heilongjiang province, China. In order to monitor the static and dynamic responses of the bridge under the traffic and environmental variation, a Long-Term continuous Monitoring System was designed and installed on Fu Sui Bridge in April 2012. A hydrostatic leveling System was used to measure the displacement and fiber Bragg grating sensors were used to measure strain, acceleration and temperature. Moreover, other necessary components including data acquisition and transmission, data calculation and analysis software are also described. Summer and winter Monitoring data are also presented. This paper focuses on: (1) the design and installation of the Long-Term continuous Monitoring System hardware and (2) the operating pattern and function of the automatic Monitoring System. After more than one year successful conducting, the System has provided a large amount of data records for daily management and research of the bridge. This System can be applied to extremely cold region.
Joao Bento - One of the best experts on this subject based on the ideXlab platform.
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construction assessment and long term prediction of prestressed concrete bridges based on Monitoring data
Engineering Structures, 2013Co-Authors: Helder Sousa, Joao Bento, Joaquim FigueirasAbstract:Abstract The Long-Term assessment of large civil infrastructures such as prestressed concrete bridges is a challenging task. The real time history related to the phased construction, the influence of the adopted constructive method, the characterization of the employed concrete and the environmental conditions are crucial aspects for accurate predictions based on Finite Element Models. Data from Long-Term Monitoring Systems have been used to improve the quality of those predictions, namely to validate the design assumptions, to calibrate the structural model, and to update the safety coefficients. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 1700 m long viaduct, which was erected using a movable scaffolding System. A Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. Based on these measurements, this work presents the analysis strategy adopted to compute the Long-Term behaviour based on a Finite Element Model. A detailed scanning of all information with relevance for the viaduct behaviour was performed. A full discussion concerning the real Long-Term behaviour is made, focusing the differences between the measurements and the results obtained with the numerical model, namely the trends due to shrinkage and creep and the variations due to the temperature. Finally, concerning to the viaduct lifetime, the predicted values for the measured parameters are updated, since the predictions based on the European standard rules presents significant bias to be used as reference values regarding the viaduct surveillance.
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construction assessment and long term prediction of prestressed concrete bridges based on Monitoring data
Engineering Structures, 2013Co-Authors: Helder Sousa, Joao Bento, Joaquim FigueirasAbstract:Abstract The Long-Term assessment of large civil infrastructures such as prestressed concrete bridges is a challenging task. The real time history related to the phased construction, the influence of the adopted constructive method, the characterization of the employed concrete and the environmental conditions are crucial aspects for accurate predictions based on Finite Element Models. Data from Long-Term Monitoring Systems have been used to improve the quality of those predictions, namely to validate the design assumptions, to calibrate the structural model, and to update the safety coefficients. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 1700 m long viaduct, which was erected using a movable scaffolding System. A Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. Based on these measurements, this work presents the analysis strategy adopted to compute the Long-Term behaviour based on a Finite Element Model. A detailed scanning of all information with relevance for the viaduct behaviour was performed. A full discussion concerning the real Long-Term behaviour is made, focusing the differences between the measurements and the results obtained with the numerical model, namely the trends due to shrinkage and creep and the variations due to the temperature. Finally, concerning to the viaduct lifetime, the predicted values for the measured parameters are updated, since the predictions based on the European standard rules presents significant bias to be used as reference values regarding the viaduct surveillance.
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Long-Term Monitoring and assessment of a precast continuous viaduct
Structure and Infrastructure Engineering, 2013Co-Authors: Helder Sousa, Joao Bento, Carlos Sousa, Afonso Serra Neves, Joaquim FigueirasAbstract:Precast girders have recently been widely employed in the construction of bridges and viaducts. The new bridge over the Tagus River in Portugal, the Leziria Bridge, comprehends a 9160 m long south approach viaduct, which was built with precast girders made continuous in situ. Given the relevance of this construction, a Long-Term Monitoring System was implemented and measurements were taken since the start of the construction. The observed parameters were concrete strains and temperatures, deck rotations, joint displacements, accelerations and also environment temperature and relative humidity. The work presents the precast structure, the Monitoring System and the appraisal of a statistical procedure for the Long-Term assessment of the structural behaviour. This procedure is based on prediction models, which establish the normal correlation patterns between environmental and material parameters (such as concrete temperature and shrinkage strains), and the observed structural response in terms of strains, r...
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design and implementation of a Monitoring System applied to a long span prestressed concrete bridge
Structural Concrete, 2011Co-Authors: Helder Sousa, Carlos Felix, Joao Bento, Joaquim FigueirasAbstract:Currently, Long-Term Monitoring Systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the Long-Term Monitoring System installed on the new Leziria Bridge over the River Tagus in Portugal. The System was developed to control some aspects of the construction process and to survey the service life of the structure. A set of structural, durability and environmental parameters defining the bridge condition are remotely assessed in real-time via a fibreoptic network. Aspects such as architecture, installation and functionality of the Monitoring System are discussed and the innovative aspects of the implementation are highlighted. In this context, the main goal of this work is to present the Long-Term Monitoring System of Leziria Bridge, sharing the experiences, the solutions and the procedures adopted, given their potential usefulness in the implementation of similar projects. Copyright © 2011 Ernst & Sohn Verlag fur Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.
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design and implementation of a Monitoring System applied to a long span prestressed concrete bridge
Structural Concrete, 2011Co-Authors: Helder Sousa, Carlos Felix, Joao Bento, Joaquim FigueirasAbstract:Currently, Long-Term Monitoring Systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the Long-Term Monitoring System installed on the new Leziria Bridge over the River Tagus in Portugal. The System was developed to control some aspects of the construction process and to survey the service life of the structure. A set of structural, durability and environmental parameters defining the bridge condition are remotely assessed in real-time via a fibreoptic network. Aspects such as architecture, installation and functionality of the Monitoring System are discussed and the innovative aspects of the implementation are highlighted. In this context, the main goal of this work is to present the Long-Term Monitoring System of Leziria Bridge, sharing the experiences, the solutions and the procedures adopted, given their potential usefulness in the implementation of similar projects. Copyright © 2011 Ernst & Sohn Verlag fur Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.
Chuang Chen - One of the best experts on this subject based on the ideXlab platform.
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Temperature Effects on Strains of a Continuous Box-Girder Bridge with a Long-Term Monitoring System
Structural Health Monitoring 2015, 2015Co-Authors: Chuang Chen, Mosbeh R. Kaloop, Zong Lin Wang, Qing Fei GaoAbstract:Daily and seasonal temperature-induced strains of a prestressed concrete (PSC) continuous box-girder bridge were presented. Strain measurement, using fiber Bragg grating sensors, constitutes a crucial component of the System in the Monitoring of the bridge’s key sections response in order to evaluate its structural behavior under environmental and traffic loads. This study was carried out to determine the effects of daily and seasonal temperature variations on the bridge deformation. Moreover, the insolation generates vertical temperature gradients in the box-girder cross sections, which are responsible for the strain differences in the plates and for its variation in the webs along their heights. In addition, in order to identify the qualitative and quantitative relation between the temperature and the strains on the cross sections, the Monitoring temperature measurements of the bridge during the construction were applied. The results show that: (1) the seasonal temperature variation can significantly influence the strain of concrete bridges in cold regions; (2) in the high temperature periods the strain of the box-girder top plates experiences the largest variation, whereas for the bottom plates deformation the low temperature periods have a higher impact; (3) the daily and seasonal strain variations induced by uniform temperature reveal an inconsistent tendency for mid-span cross sections. doi: 10.12783/SHM2015/104
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Design of a Long-Term Monitoring System for a PSC Continuous Box- girder Bridge
Key Engineering Materials, 2014Co-Authors: Chuang Chen, R. Kaloop Mosbeh, Zong Lin Wang, Qing Fei Gao, Jun Fei ZhongAbstract:Structural Health Monitoring is becoming an increasingly common tool to obtain the Long-Term performance of infrastructures and buildings. Many structural health Monitoring Systems were developed and applied to different bridges in the world. However, very little is known on the applications in extreme cold environment. Fu Sui Bridge, a 1070 m variable cross-section continuous box-girder bridge, is located in the coldest province -- Heilongjiang province, China. In order to monitor the static and dynamic responses of the bridge under the traffic and environmental variation, a Long-Term continuous Monitoring System was designed and installed on Fu Sui Bridge in April 2012. A hydrostatic leveling System was used to measure the displacement and fiber Bragg grating sensors were used to measure strain, acceleration and temperature. Moreover, other necessary components including data acquisition and transmission, data calculation and analysis software are also described. Summer and winter Monitoring data are also presented. This paper focuses on: (1) the design and installation of the Long-Term continuous Monitoring System hardware and (2) the operating pattern and function of the automatic Monitoring System. After more than one year successful conducting, the System has provided a large amount of data records for daily management and research of the bridge. This System can be applied to extremely cold region.
