Pub Date : 2022-01-01DOI: 10.2749/nanjing.2022.0767
Juhui Zhang, Yuchuan Zhao
To facilitate the reuse of the internal mold of precast multi-box girder and accelerate bridge construction, the torsional crossbeam at the end of precast simply supported multi-box girder needs to be changed to post-cast in-situ. Finite Element Modelling package ABAQUS 2021 was used to model the interfacial shear behaviour of the three-dimensional Z-shaped straight shear specimens. The models took into account the bond-slip relationship between the old and new concrete interfaces and the interaction between the concrete and the shear key. The models were validated and calibrated based on the experimental results. The study shows that the rigid shear key can improve the shear load capacity of the specimen at the new and old concrete interface. The difference between the model and experimental results is relatively small and therefore it shows the capability of the finite element modelling to carry out parametric analysis.
{"title":"FE Modeling of the Interfacial Behaviour of Precast Multi-box Girder","authors":"Juhui Zhang, Yuchuan Zhao","doi":"10.2749/nanjing.2022.0767","DOIUrl":"https://doi.org/10.2749/nanjing.2022.0767","url":null,"abstract":"To facilitate the reuse of the internal mold of precast multi-box girder and accelerate bridge construction, the torsional crossbeam at the end of precast simply supported multi-box girder needs to be changed to post-cast in-situ. Finite Element Modelling package ABAQUS 2021 was used to model the interfacial shear behaviour of the three-dimensional Z-shaped straight shear specimens. The models took into account the bond-slip relationship between the old and new concrete interfaces and the interaction between the concrete and the shear key. The models were validated and calibrated based on the experimental results. The study shows that the rigid shear key can improve the shear load capacity of the specimen at the new and old concrete interface. The difference between the model and experimental results is relatively small and therefore it shows the capability of the finite element modelling to carry out parametric analysis.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126084259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.1256
S. Komarizadehasl, Ahmad Alahmad, J. Lozano-Galant, V. Torralba, G. Ramos, J. Turmo
Structural Health Monitoring applications are receiving more and more attention nowadays. The epidemic problem with these evaluations is their high cost. For applying them to structures/ infrastructures with a low budget of SHM evaluations, low-cost sensors must be taken into account. However, low-cost accelerometers have higher noise density ratios which affect their accuracy and resolution. Using filters or post-processing methods alters the acquired information of the accelerometers. This article aims to enhance the accuracy and resolution of low-cost sensors by improving and controlling the spectral noise level through active noise improvement. This improvement is studied in this paper and supportive laboratory experiments have been illustrated.
{"title":"Beneficial Effect of Combining Similar Low-Cost Accelerometer to improve the overall Accuracy and Noise Density","authors":"S. Komarizadehasl, Ahmad Alahmad, J. Lozano-Galant, V. Torralba, G. Ramos, J. Turmo","doi":"10.2749/nanjing.2022.1256","DOIUrl":"https://doi.org/10.2749/nanjing.2022.1256","url":null,"abstract":"Structural Health Monitoring applications are receiving more and more attention nowadays. The epidemic problem with these evaluations is their high cost. For applying them to structures/ infrastructures with a low budget of SHM evaluations, low-cost sensors must be taken into account. However, low-cost accelerometers have higher noise density ratios which affect their accuracy and resolution. Using filters or post-processing methods alters the acquired information of the accelerometers. This article aims to enhance the accuracy and resolution of low-cost sensors by improving and controlling the spectral noise level through active noise improvement. This improvement is studied in this paper and supportive laboratory experiments have been illustrated.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124259087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.0444
Mohammed Elhassan, Ledong Zhu, Z. Tan, Wael Alhaddad
Aerodynamic shape optimization of bridge deck is a very important task in the wind-resistant design of long-span bridges and often carried out via wind tunnel tests of sectional model or CFD simulation, both of which commonly need heavy workload, thus are time-consuming and costly. In this paper, an artificial neural network (ANN) model was developed to predict aerodynamic coefficients of a central-slotted box deck of a 1600m main span cable-stayed bridge during the aerodynamic shape optimization to enhance its performance of wind-induced static stability. The ANN model was built and trained with a data set of aerodynamic coefficients obtained from limited cases of wind tunnel tests. The effect of neuron numbers in the hidden layer on prediction accuracy was discussed. The results show that the built ANN model can accurately predict the aerodynamic coefficients and significantly reduce the workload of wind tunnel tests.
{"title":"Prediction of Aerodynamic Coefficients using Artificial Neural Network in Shape Optimization of Centrally-Slotted Box Deck Bridge","authors":"Mohammed Elhassan, Ledong Zhu, Z. Tan, Wael Alhaddad","doi":"10.2749/nanjing.2022.0444","DOIUrl":"https://doi.org/10.2749/nanjing.2022.0444","url":null,"abstract":"Aerodynamic shape optimization of bridge deck is a very important task in the wind-resistant design of long-span bridges and often carried out via wind tunnel tests of sectional model or CFD simulation, both of which commonly need heavy workload, thus are time-consuming and costly. In this paper, an artificial neural network (ANN) model was developed to predict aerodynamic coefficients of a central-slotted box deck of a 1600m main span cable-stayed bridge during the aerodynamic shape optimization to enhance its performance of wind-induced static stability. The ANN model was built and trained with a data set of aerodynamic coefficients obtained from limited cases of wind tunnel tests. The effect of neuron numbers in the hidden layer on prediction accuracy was discussed. The results show that the built ANN model can accurately predict the aerodynamic coefficients and significantly reduce the workload of wind tunnel tests.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"122 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120840396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.1715
D. Achillopoulou, N. K. Stamataki, A. Psathas, L. Iliadis, A. Karabinis
Lately, there is an increasing demand for resilient infrastructure assets. To support the documentation of resilience, Structural Health Monitoring (SHM) data is a necessity, as well as traffic loads. Those diagnosis and function data can be the basis for the prognosis of future prediction for the performance of the assets. Towards this direction, this paper develops a new methodology that uses real monitoring data and Artificial Intelligence (AI) algorithms to quantify the resilience based on future traffic load predictions of functionality. It includes the case study of the “Hollandse Brug” bridge in the Netherlands considering strains and traffic load predictions and other external. Resilience is derived as a function of both functional and structural parameters throughout the lifecycle. The quantification is supported by sustainability indices and key performance indicators representing the traffic flow, the structural integrity and the sustainability level of the asset.
{"title":"Resilience Quantification Based on Monitoring & Prediction Data Using Artificial Intelligence (AI)","authors":"D. Achillopoulou, N. K. Stamataki, A. Psathas, L. Iliadis, A. Karabinis","doi":"10.2749/nanjing.2022.1715","DOIUrl":"https://doi.org/10.2749/nanjing.2022.1715","url":null,"abstract":"Lately, there is an increasing demand for resilient infrastructure assets. To support the documentation of resilience, Structural Health Monitoring (SHM) data is a necessity, as well as traffic loads. Those diagnosis and function data can be the basis for the prognosis of future prediction for the performance of the assets. Towards this direction, this paper develops a new methodology that uses real monitoring data and Artificial Intelligence (AI) algorithms to quantify the resilience based on future traffic load predictions of functionality. It includes the case study of the “Hollandse Brug” bridge in the Netherlands considering strains and traffic load predictions and other external. Resilience is derived as a function of both functional and structural parameters throughout the lifecycle. The quantification is supported by sustainability indices and key performance indicators representing the traffic flow, the structural integrity and the sustainability level of the asset.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127164278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.0387
Z. Xiong, Xu Hou, Houda Zhu, Yuqing Liu, Yang Meng
To investigate the structural performance and economic applicability of multi-span extradosed cable-stayed bridge, a comparative scheme of composite beam with corrugated steel web was designed based on the Wangjia River Bridge, which was an extradosed cable-stayed bridge with prestressed concrete girder built in Shaanxi. Spatial finite element models of the whole bridge were established by CSIBridge for extradosed cable-stayed bridge with two different sections of girder. Considering the influence of p-Δ effect, the vertical and horizontal deformation and the governing sections of the two forms were analyzed and compared. The material consumption of steel, concrete and steel strand of the extradosed cable-stayed bridge with corrugated steel web was calculated. The material consumption of the two schemes was compared. The differences in structural performance and economic cost for the two structures were explored. It’s expected to provide a reference for the tender design of multi-span extradosed cable-stayed bridges with similar span length.
{"title":"Structural Performance and Cost Analysis of Multi-span Extradosed Cable-Stayed Bridge","authors":"Z. Xiong, Xu Hou, Houda Zhu, Yuqing Liu, Yang Meng","doi":"10.2749/nanjing.2022.0387","DOIUrl":"https://doi.org/10.2749/nanjing.2022.0387","url":null,"abstract":"To investigate the structural performance and economic applicability of multi-span extradosed cable-stayed bridge, a comparative scheme of composite beam with corrugated steel web was designed based on the Wangjia River Bridge, which was an extradosed cable-stayed bridge with prestressed concrete girder built in Shaanxi. Spatial finite element models of the whole bridge were established by CSIBridge for extradosed cable-stayed bridge with two different sections of girder. Considering the influence of p-Δ effect, the vertical and horizontal deformation and the governing sections of the two forms were analyzed and compared. The material consumption of steel, concrete and steel strand of the extradosed cable-stayed bridge with corrugated steel web was calculated. The material consumption of the two schemes was compared. The differences in structural performance and economic cost for the two structures were explored. It’s expected to provide a reference for the tender design of multi-span extradosed cable-stayed bridges with similar span length.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125545393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.0912
Álvaro Rojas, M. Valenzuela, Alvaro Peña
Within a project related to the area of bridges, we work with different tools and between this information is usually managed through the use of CAD drawings made basically in 2D.Today, a new concept of BIM applied to bridges called Bridge Information Modeling (BrIM), which well implies being a methodology with different uses and being the solution in helping the different parties to work more collaboratively, effectively and simultaneously.This paper presents the experience of applying one of these uses in the phase of analysis and structural diagnosis of ten bridges in Chile, which demonstrates that this technology becomes a valuable tool for information management through the virtual model worked between the different parties involved in the maintenance and operation of a project.
{"title":"Structural Detailing of Bridges, Making Use of the Brim Methodology (Bridge Information Modeling), through the Creation of Parametric Models and As-Build Plans","authors":"Álvaro Rojas, M. Valenzuela, Alvaro Peña","doi":"10.2749/nanjing.2022.0912","DOIUrl":"https://doi.org/10.2749/nanjing.2022.0912","url":null,"abstract":"Within a project related to the area of bridges, we work with different tools and between this information is usually managed through the use of CAD drawings made basically in 2D.Today, a new concept of BIM applied to bridges called Bridge Information Modeling (BrIM), which well implies being a methodology with different uses and being the solution in helping the different parties to work more collaboratively, effectively and simultaneously.This paper presents the experience of applying one of these uses in the phase of analysis and structural diagnosis of ten bridges in Chile, which demonstrates that this technology becomes a valuable tool for information management through the virtual model worked between the different parties involved in the maintenance and operation of a project.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116584500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.1161
Neyu Chen, Y. Ge
A bridge wind resistance database has been built based on the wind tunnel testing results of 20 long-span bridges. The artificial intelligence models for identifying aerostatic coefficients and flutter derivatives of close box girders are trained and developed via machine learning methods, including error back propagation neural network based on Levenberg-Marquardt algorithm and gradient boosting decision tree. The identification of the aerostatic coefficients can be achieved with high accuracy. For flutter derivatives, the model can also explore the underlying distribution of dataset. In this way, the present research work can make the identification of aerodynamic parameters separated from tedious wind tunnel test and complex numerical simulation to some extent. It can also provide a convenient and feasible option for expanding data sets of aerodynamic parameters. In addition, it can help determine the appropriate shape of the box girder cross-section in preliminary design stage of long-span bridge and provide the necessary reference for the aerodynamic shape optimization by modifying local geometric features of the cross-section to evaluate the influence of the aerodynamic shape on flutter performance.
{"title":"Aerodynamic Parameter Identification and Flutter Performance Prediction of Closed Box Girder Based on Machine Learning","authors":"Neyu Chen, Y. Ge","doi":"10.2749/nanjing.2022.1161","DOIUrl":"https://doi.org/10.2749/nanjing.2022.1161","url":null,"abstract":"A bridge wind resistance database has been built based on the wind tunnel testing results of 20 long-span bridges. The artificial intelligence models for identifying aerostatic coefficients and flutter derivatives of close box girders are trained and developed via machine learning methods, including error back propagation neural network based on Levenberg-Marquardt algorithm and gradient boosting decision tree. The identification of the aerostatic coefficients can be achieved with high accuracy. For flutter derivatives, the model can also explore the underlying distribution of dataset. In this way, the present research work can make the identification of aerodynamic parameters separated from tedious wind tunnel test and complex numerical simulation to some extent. It can also provide a convenient and feasible option for expanding data sets of aerodynamic parameters. In addition, it can help determine the appropriate shape of the box girder cross-section in preliminary design stage of long-span bridge and provide the necessary reference for the aerodynamic shape optimization by modifying local geometric features of the cross-section to evaluate the influence of the aerodynamic shape on flutter performance.","PeriodicalId":410450,"journal":{"name":"IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114379378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2749/nanjing.2022.0758
Xiuyu Chen, Ledong Zhu, Z. Tan
Unsteady characteristics of aerodynamic force and wind-induced pressure on a 3:2 rectangular section under accelerating airflow are investigated through wind tunnel experiments. Three aerodynamic coefficients, drag coefficient Cd(t), RMS of lift coefficient Clrms(t), Strouhal number of the rectangular section in the accelerating airflow with or without initial velocity are compared with those of the steady flow. Results show that in the cases of airflow accelerated from the static state, significant unsteady feature appears in all three aerodynamic coefficients, 𝐶𝐶𝑑𝑑(𝑡𝑡) and