Hysteresis behavior of structural components has been one of the research focus for the structural engineering community for decades, comprehensively determines the structural performance and safety, and plays an important role in structural disaster mitigation. It is of great significance to continuously monitor structural responses and accurately characterize structural hysteresis. Currently, the nonlinear properties of real‐world structural components cannot be obtained before its failure. Thus, a historical database is collected firstly. Then, a data‐driven analysis method is proposed for predicting hysteresis behaviors of reinforced concrete (RC) columns. A bidirectional LSTM (BLSTM) network is developed to model and predict hysteresis curves. The data with unfixed lengths are specially processed to simultaneously guarantee a uniform size and avoid data loss, and the clipping layers are inserted in the model to clip off inferior predictions and improve the accuracy. This methodology is systematically studied and validated by employing a sythetic database generated by numerical simulation and the full‐scale experiment database named PEER database. Result shows that proposed BLSTM can predict the hysteresis curves of the RC components with acceptable accuracy and robustness. Moreover, the interpretability analysis is performed on identifying the learning and prediction principle of the BLSTM model on hysteresis prediction and its accuracy variation under different model architectures.
{"title":"Data‐driven modeling and prediction on hysteresis behavior of flexure RC columns using deep learning networks","authors":"Jiangmeng Guo, Luji Wang, Jiazeng Shan","doi":"10.1002/tal.2039","DOIUrl":"https://doi.org/10.1002/tal.2039","url":null,"abstract":"Hysteresis behavior of structural components has been one of the research focus for the structural engineering community for decades, comprehensively determines the structural performance and safety, and plays an important role in structural disaster mitigation. It is of great significance to continuously monitor structural responses and accurately characterize structural hysteresis. Currently, the nonlinear properties of real‐world structural components cannot be obtained before its failure. Thus, a historical database is collected firstly. Then, a data‐driven analysis method is proposed for predicting hysteresis behaviors of reinforced concrete (RC) columns. A bidirectional LSTM (BLSTM) network is developed to model and predict hysteresis curves. The data with unfixed lengths are specially processed to simultaneously guarantee a uniform size and avoid data loss, and the clipping layers are inserted in the model to clip off inferior predictions and improve the accuracy. This methodology is systematically studied and validated by employing a sythetic database generated by numerical simulation and the full‐scale experiment database named PEER database. Result shows that proposed BLSTM can predict the hysteresis curves of the RC components with acceptable accuracy and robustness. Moreover, the interpretability analysis is performed on identifying the learning and prediction principle of the BLSTM model on hysteresis prediction and its accuracy variation under different model architectures.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44500197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Concrete‐filled steel tubes (CFSTs) have received growing attention, owing to their rapid construction, reduced labor requirement, and reasonable material cost. While in service, the CFSTs can be subjected to unexpected impact loads, originating from vehicle and vessel collision, as well as water‐ and wind‐borne debris impact. Such extreme loading events often cause a partial or complete failure of conventional CFSTs, risking the safety and performance of the entire structural systems that rely on them. To address this issue, the current study explores how two advanced composite materials, including ultra‐high‐performance fiber‐reinforced concrete (UHPFRC) and carbon fiber‐reinforced polymer (CFRP), can be utilized to provide superior mechanical properties and minimize the vulnerability of CFSTs to impact loads. The composite materials under consideration are appropriate for both new and existing structures, in which normal‐strength concrete can be replaced with UHPFRC, while CFRP sheets can further strengthen the CFSTs. For obtaining in‐depth insights, a computational framework validated with the experimental tests was developed in the current study. Using a set of representative impact scenarios, various response measures, such as internal forces and deflections, as well as the energy absorbed by the CFSTs, were recorded during impact simulations. The investigations were then further extended to capture the influence of the main design parameters related to concrete, CFRP, and steel tube. From the conducted investigations, an energy absorption index was introduced, as a measure to evaluate the performance of CFSTs under impact loads.
{"title":"Synergistic use of ultra‐high‐performance fiber‐reinforced concrete (UHPFRC) and carbon fiber‐reinforced polymer (CFRP) for improving the impact resistance of concrete‐filled steel tubes","authors":"D. Saini, B. Shafei","doi":"10.1002/tal.2036","DOIUrl":"https://doi.org/10.1002/tal.2036","url":null,"abstract":"Concrete‐filled steel tubes (CFSTs) have received growing attention, owing to their rapid construction, reduced labor requirement, and reasonable material cost. While in service, the CFSTs can be subjected to unexpected impact loads, originating from vehicle and vessel collision, as well as water‐ and wind‐borne debris impact. Such extreme loading events often cause a partial or complete failure of conventional CFSTs, risking the safety and performance of the entire structural systems that rely on them. To address this issue, the current study explores how two advanced composite materials, including ultra‐high‐performance fiber‐reinforced concrete (UHPFRC) and carbon fiber‐reinforced polymer (CFRP), can be utilized to provide superior mechanical properties and minimize the vulnerability of CFSTs to impact loads. The composite materials under consideration are appropriate for both new and existing structures, in which normal‐strength concrete can be replaced with UHPFRC, while CFRP sheets can further strengthen the CFSTs. For obtaining in‐depth insights, a computational framework validated with the experimental tests was developed in the current study. Using a set of representative impact scenarios, various response measures, such as internal forces and deflections, as well as the energy absorbed by the CFSTs, were recorded during impact simulations. The investigations were then further extended to capture the influence of the main design parameters related to concrete, CFRP, and steel tube. From the conducted investigations, an energy absorption index was introduced, as a measure to evaluate the performance of CFSTs under impact loads.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44528434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Issue Information","authors":"","doi":"10.1002/tal.1958","DOIUrl":"https://doi.org/10.1002/tal.1958","url":null,"abstract":"No abstract is available for this article.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48857234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Goodarzi, M. Moradi, Pedram Jalali, Moein Abdolmohammadi, Seyed Milad Hasheminejad
Fragility curves development in structures has always been a focus of research interest among structural and earthquake engineers for which the maximum story drift is usually considered as the engineering demand parameter (EDP) known as the conventional approach. This paper aims at calculating the fragility curves of a tall building with outrigger braced system by considering the plastic strain energy as the EDP and compare it with the conventional approach. In addition, the effect of optimizing the position of outriggers on the exceedance probability of the structure under near‐ and far‐fault seismic loadings is investigated in this paper. Fragility curves of this structure in four performance levels including immediate occupancy (IO), life safety (LS), collapse prevention (CP), and instability is extracted based on the conventional method. The fragility curves for the aforementioned performance levels are also extracted based on the plastic strain energy and compared with the conventional approach. The results have demonstrated that optimizing the location of the bracing system would lower the exceedance probability of the structure. Moreover, the exceedance probability of the investigated building with outrigger braced system under far‐fault records in various levels is more than that of near‐fault records. It is also concluded that the conventional approach would lead to more conservative results compared with the energy approach.
{"title":"Fragility assessment of an outrigger structure system based on energy method","authors":"M. Goodarzi, M. Moradi, Pedram Jalali, Moein Abdolmohammadi, Seyed Milad Hasheminejad","doi":"10.1002/tal.2017","DOIUrl":"https://doi.org/10.1002/tal.2017","url":null,"abstract":"Fragility curves development in structures has always been a focus of research interest among structural and earthquake engineers for which the maximum story drift is usually considered as the engineering demand parameter (EDP) known as the conventional approach. This paper aims at calculating the fragility curves of a tall building with outrigger braced system by considering the plastic strain energy as the EDP and compare it with the conventional approach. In addition, the effect of optimizing the position of outriggers on the exceedance probability of the structure under near‐ and far‐fault seismic loadings is investigated in this paper. Fragility curves of this structure in four performance levels including immediate occupancy (IO), life safety (LS), collapse prevention (CP), and instability is extracted based on the conventional method. The fragility curves for the aforementioned performance levels are also extracted based on the plastic strain energy and compared with the conventional approach. The results have demonstrated that optimizing the location of the bracing system would lower the exceedance probability of the structure. Moreover, the exceedance probability of the investigated building with outrigger braced system under far‐fault records in various levels is more than that of near‐fault records. It is also concluded that the conventional approach would lead to more conservative results compared with the energy approach.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44987718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Issue Information","authors":"","doi":"10.1002/tal.2016","DOIUrl":"https://doi.org/10.1002/tal.2016","url":null,"abstract":"No abstract is available for this article.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46094780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tall buildings located in Hong Kong can suffer great damage caused by typhoon hazards throughout their lifetimes. In addition, the effect of wind hazards may be exacerbated due to increases in the typhoon intensity and frequency caused by the climate change effect. Therefore, developing a framework to evaluate and quantify the damage caused by wind hazards on tall buildings from the economic perspective is critical for engineers and building owners in designing a cost‐effective tall building. In this study, an economic damage indicator, life‐cycle cost, is measured by using a probabilistic method called life‐cycle cost analysis (LCCA). Moreover, the building sector is one of the biggest contributors to greenhouse gas (GHG) emissions, and the environmental impact that may be generated in intervention activities after wind‐induced damage occurs is analyzed. An environmental impact indicator, embodied carbon emission, is quantified by employing another probabilistic method called life‐cycle assessment (LCA). Therefore, an integrated methodology combining the LCCA and LCA is proposed to evaluate potential damage costs and environmental impact caused by typhoon hazards on tall buildings.
{"title":"Life‐cycle cost analysis and life‐cycle assessment of the second‐generation benchmark building subject to typhoon wind loads in Hong Kong","authors":"Siqi Cao, Jiayao Wang, T. Tse","doi":"10.1002/tal.2014","DOIUrl":"https://doi.org/10.1002/tal.2014","url":null,"abstract":"Tall buildings located in Hong Kong can suffer great damage caused by typhoon hazards throughout their lifetimes. In addition, the effect of wind hazards may be exacerbated due to increases in the typhoon intensity and frequency caused by the climate change effect. Therefore, developing a framework to evaluate and quantify the damage caused by wind hazards on tall buildings from the economic perspective is critical for engineers and building owners in designing a cost‐effective tall building. In this study, an economic damage indicator, life‐cycle cost, is measured by using a probabilistic method called life‐cycle cost analysis (LCCA). Moreover, the building sector is one of the biggest contributors to greenhouse gas (GHG) emissions, and the environmental impact that may be generated in intervention activities after wind‐induced damage occurs is analyzed. An environmental impact indicator, embodied carbon emission, is quantified by employing another probabilistic method called life‐cycle assessment (LCA). Therefore, an integrated methodology combining the LCCA and LCA is proposed to evaluate potential damage costs and environmental impact caused by typhoon hazards on tall buildings.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47697863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The large‐span metal roof systems can produce a significant nonuniform temperature effect under solar radiation, leading to potential safety hazards. An experiment is conducted to study the nonuniform thermal behavior of a small‐scale continuous welded stainless steel roof (CWSSR) system under solar radiation. The small‐scale CWSSR system considered different roof slopes and sunward side and nightside. The efficiency of the numerical analysis of the thermal behavior of the roof slab is verified in comparison with the experimental results. Based on the numerical and experimental results, the thermal effect of a full‐scale CWSSR system is studied under different orientations, wind speeds, and atmospheric temperature. Through the analysis of research results, the nonuniform thermal features of the CWSSR system are significant and cannot be overlooked. The temperature difference between the sunward side and nightside roof slab is positively correlated with the roof slope. The thermal behavior of the CWSSR system is greatly influenced by wind speeds but is less affected by orientations and atmospheric temperature.
{"title":"Experimental and simulation analysis of thermal behavior of large‐span roof system under solar radiation","authors":"Mingming Wang, Z. Xin, Xuan-Xuan Liu, Tong Ou, Dayang Wang, Yongshan Zhang","doi":"10.1002/tal.2013","DOIUrl":"https://doi.org/10.1002/tal.2013","url":null,"abstract":"The large‐span metal roof systems can produce a significant nonuniform temperature effect under solar radiation, leading to potential safety hazards. An experiment is conducted to study the nonuniform thermal behavior of a small‐scale continuous welded stainless steel roof (CWSSR) system under solar radiation. The small‐scale CWSSR system considered different roof slopes and sunward side and nightside. The efficiency of the numerical analysis of the thermal behavior of the roof slab is verified in comparison with the experimental results. Based on the numerical and experimental results, the thermal effect of a full‐scale CWSSR system is studied under different orientations, wind speeds, and atmospheric temperature. Through the analysis of research results, the nonuniform thermal features of the CWSSR system are significant and cannot be overlooked. The temperature difference between the sunward side and nightside roof slab is positively correlated with the roof slope. The thermal behavior of the CWSSR system is greatly influenced by wind speeds but is less affected by orientations and atmospheric temperature.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41853358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Issue Information","authors":"","doi":"10.1002/tal.1955","DOIUrl":"https://doi.org/10.1002/tal.1955","url":null,"abstract":"No abstract is available for this article.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44130517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ying Zhou, Xiaofang Liu, Yi Xiao, Hao Wu, Meng Wang
Structures with replaceable energy‐dissipating elements are attractive systems for improving building resilience. Damage in these structures is mainly limited to dissipating elements, which can be replaced after earthquakes. Among the energy‐dissipating elements, viscoelastic dampers (VEDs) can dissipate energy even under small deformations while providing stable fatigue performances, which benefits high‐rise buildings in resisting both wind and earthquake loadings. This paper presents the seismic design of an engineering practice of a 10‐story shear wall building with replaceable viscoelastic coupling beams. A new type of viscoelastic material that has negligible frequency dependency is adopted to provide stable constraint for the wall piers. The design details, including VEDs, nonreplaceable segment, and the detachable connection, are exemplified. The numerical model of the replaceable structure is established and analyzed under dynamic loadings. Results confirm that the implementation of replaceable viscoelastic coupling beams improves structural seismic performance. The plastic rotation at the end of the coupling beam is significantly reduced up to 41.4% compared with the traditional coupled shear wall structure.
{"title":"Seismic design and engineering practice of 10‐story shear wall structure with replaceable viscoelastic coupling beams","authors":"Ying Zhou, Xiaofang Liu, Yi Xiao, Hao Wu, Meng Wang","doi":"10.1002/tal.2010","DOIUrl":"https://doi.org/10.1002/tal.2010","url":null,"abstract":"Structures with replaceable energy‐dissipating elements are attractive systems for improving building resilience. Damage in these structures is mainly limited to dissipating elements, which can be replaced after earthquakes. Among the energy‐dissipating elements, viscoelastic dampers (VEDs) can dissipate energy even under small deformations while providing stable fatigue performances, which benefits high‐rise buildings in resisting both wind and earthquake loadings. This paper presents the seismic design of an engineering practice of a 10‐story shear wall building with replaceable viscoelastic coupling beams. A new type of viscoelastic material that has negligible frequency dependency is adopted to provide stable constraint for the wall piers. The design details, including VEDs, nonreplaceable segment, and the detachable connection, are exemplified. The numerical model of the replaceable structure is established and analyzed under dynamic loadings. Results confirm that the implementation of replaceable viscoelastic coupling beams improves structural seismic performance. The plastic rotation at the end of the coupling beam is significantly reduced up to 41.4% compared with the traditional coupled shear wall structure.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47190053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammed Samier Sebaq, Ying Zhou, G. Song, Yi Xiao
Current seismic practices are more concerned with dissipating a significant portion of seismic input energy than with lateral load resistance, as well as with determining seismic demands of structures using response spectra. This study aims to improve the knowledge of the plastic energy spectra ( EP ) of single‐degree‐of‐freedom systems (SDOF) equipped with fluid viscous dampers (FVDs). This type of dampers is characterized by its supplemental damping ratio ξadd and velocity power α . Using nonlinear dynamic analyses, the EP and its ratio to the input energy ( EP/EI ) are determined using near‐field‐pulse, near‐field‐non‐pulse and far‐field ground motions. Parametric studies are conducted to investigate the effect of ground motion types, original system features and FVD characteristics on EP/EI spectra. The results show that ground motion types have a considerable influence on the EP/EI for systems with FVDs, while they are not effective for systems without FVDs. Increasing FVD nonlinearity (decreasing α) is more effective to reduce the EP/EI under near‐field‐non‐pulse and far‐field motions than under near‐field‐pulse ground motions for structures with Tn > 1 s. The paper further developed a prediction equation for estimating EP/EI for SDOF systems without and with FVDs, which can serve as a useful tool to analyse structural damage for energy‐based seismic design.
{"title":"Plastic energy evaluation of bilinear SDOF systems with fluid viscous dampers","authors":"Mohammed Samier Sebaq, Ying Zhou, G. Song, Yi Xiao","doi":"10.1002/tal.2011","DOIUrl":"https://doi.org/10.1002/tal.2011","url":null,"abstract":"Current seismic practices are more concerned with dissipating a significant portion of seismic input energy than with lateral load resistance, as well as with determining seismic demands of structures using response spectra. This study aims to improve the knowledge of the plastic energy spectra ( EP ) of single‐degree‐of‐freedom systems (SDOF) equipped with fluid viscous dampers (FVDs). This type of dampers is characterized by its supplemental damping ratio ξadd and velocity power α . Using nonlinear dynamic analyses, the EP and its ratio to the input energy ( EP/EI ) are determined using near‐field‐pulse, near‐field‐non‐pulse and far‐field ground motions. Parametric studies are conducted to investigate the effect of ground motion types, original system features and FVD characteristics on EP/EI spectra. The results show that ground motion types have a considerable influence on the EP/EI for systems with FVDs, while they are not effective for systems without FVDs. Increasing FVD nonlinearity (decreasing α) is more effective to reduce the EP/EI under near‐field‐non‐pulse and far‐field motions than under near‐field‐pulse ground motions for structures with Tn > 1 s. The paper further developed a prediction equation for estimating EP/EI for SDOF systems without and with FVDs, which can serve as a useful tool to analyse structural damage for energy‐based seismic design.","PeriodicalId":49470,"journal":{"name":"Structural Design of Tall and Special Buildings","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48658532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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