This study experimentally and numerically examines the performance of low‐strength reinforced concrete (LS RC) columns confined with external post‐tensioned metal straps (PTMS). Twelve square columns of cross‐section 125 × 125 mm and height 1500 mm were subjected to axial load, with eight columns being eccentrically loaded. Four columns were control specimens without confinement, and another eight were confined using a novel technique that provides active confinement through the PTMS. The main parameters investigated included the PTMS confinement ratio (ρv = 0.64% and 1.28%) and different eccentricities (e/b = 0, 0.25, 0.5 or 1.0, where e = eccentricity). The results show that the capacity and axial displacement of the PTMS‐confined columns increased by up to 43% and 116% over unconfined control columns. Finite element analyses of the columns were carried out in Abaqus® to provide further insight into the behavior of PTMS‐confined columns. This study contributes towards developing cost‐effective confinement solutions for LS RC columns, thus encouraging the broader adoption of active confinement techniques in practical strengthening applications.
{"title":"Performance of eccentrically loaded low‐strength RC columns confined with posttensioned metal straps: An experimental and numerical investigation","authors":"Ram Prasad Neupane, Thanongsak Imjai, Reyes Garcia, Yie Sue Chua, Sandeep Chaudhary","doi":"10.1002/suco.202301026","DOIUrl":"https://doi.org/10.1002/suco.202301026","url":null,"abstract":"This study experimentally and numerically examines the performance of low‐strength reinforced concrete (LS RC) columns confined with external post‐tensioned metal straps (PTMS). Twelve square columns of cross‐section 125 × 125 mm and height 1500 mm were subjected to axial load, with eight columns being eccentrically loaded. Four columns were control specimens without confinement, and another eight were confined using a novel technique that provides active confinement through the PTMS. The main parameters investigated included the PTMS confinement ratio (<jats:italic>ρ</jats:italic><jats:sub><jats:italic>v</jats:italic></jats:sub> = 0.64% and 1.28%) and different eccentricities (<jats:italic>e</jats:italic><jats:italic>/b</jats:italic> = 0, 0.25, 0.5 or 1.0, where <jats:italic>e</jats:italic> = eccentricity). The results show that the capacity and axial displacement of the PTMS‐confined columns increased by up to 43% and 116% over unconfined control columns. Finite element analyses of the columns were carried out in Abaqus® to provide further insight into the behavior of PTMS‐confined columns. This study contributes towards developing cost‐effective confinement solutions for LS RC columns, thus encouraging the broader adoption of active confinement techniques in practical strengthening applications.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"15 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203987","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 immediate functionality of bridges following severe earthquakes is vital for uninterrupted rescue operations. Regarding the significance of resiliency in bridges, post‐tensioned (PT) rocking piers with low residual displacements and minimal damages have developed over the past few decades. The rocking mechanism at two ends of the pier avoids bending moments and excessive flexural damage. The self‐centering (SC) capacity in this system is provided through post‐tensioning forces. Concerning optimum seismic design and retrofit purposes, it is essential to predict the actual degree of seismic damage and SC capacity of PT rocking systems after seismic hazards. In this case, a self‐centering index (SI) is proposed to evaluate the SC capacity when piers are subjected to cyclic and seismic loadings. This SI, when used in co‐operation with a viable damage prediction model, predicts whether or not the piers remain reparable under cyclic or seismic loading scenarios. After comparing a number of energy‐based damage indices, all of which consider the cumulative hysteresis energy, with the input energy‐based damage index (IEB‐DI), the latter was calibrated against observed damages under cyclic loading tests. This DI was chosen as the most suitable damage prediction model and was considered to be simply applicable after time history analysis. In this study, the seismic performance of a seismic‐resistant dual system, consisting of three RC bents along with an SC bent, was evaluated using the aforementioned damage limit states and the introduced SI. The damage predictions of the monolithic bridge, as the reference model, were compared with the estimated damage to the dual bridge. The results show that the joint application of the IEB‐DI and the proposed SI in predicting the performance level of SC rocking piers results in a comprehensive damage prediction model.
严重地震发生后，桥梁能否立即发挥作用对于不间断的救援行动至关重要。关于桥梁韧性的重要性，在过去几十年中，已经开发出了残余位移小、损坏程度小的后张法（PT）摇动桥墩。桥墩两端的摇晃机制可避免弯矩和过度的挠曲破坏。这种系统的自定心（SC）能力是通过后张力提供的。为了达到最佳抗震设计和改造目的，必须预测 PT 摇摆系统在地震灾害后的实际震损程度和自定心能力。在这种情况下，我们提出了一种自定心指数（SI），用于评估桥墩在承受循环荷载和地震荷载时的自定心能力。该 SI 与可行的损坏预测模型配合使用时，可预测桥墩在循环或地震荷载情况下是否仍可修复。基于输入能量的损伤指数（IEB-DI）考虑了累积滞后能量，在比较了许多基于能量的损伤指数后，根据循环加载试验下观察到的损伤情况对 IEB-DI 进行了校准。该损毁指数被选为最合适的损毁预测模型，并被认为可在时间历程分析后简单应用。在本研究中，使用上述破坏极限状态和引入的 SI 评估了抗震双系统的抗震性能，该系统由三个 RC 弯道和一个 SC 弯道组成。将作为参考模型的整体桥梁的破坏预测与双桥的估计破坏进行了比较。结果表明，联合应用 IEB-DI 和拟议的 SI 预测 SC 摇动桥墩的性能水平，可以得到一个全面的损坏预测模型。
{"title":"Damage assessment of self‐centering rocking piers using an input energy‐based damage prediction model coupled with self‐centering index","authors":"Rezvan Ashouri, Mahmoud R. Shiravand","doi":"10.1002/suco.202301146","DOIUrl":"https://doi.org/10.1002/suco.202301146","url":null,"abstract":"The immediate functionality of bridges following severe earthquakes is vital for uninterrupted rescue operations. Regarding the significance of resiliency in bridges, post‐tensioned (PT) rocking piers with low residual displacements and minimal damages have developed over the past few decades. The rocking mechanism at two ends of the pier avoids bending moments and excessive flexural damage. The self‐centering (SC) capacity in this system is provided through post‐tensioning forces. Concerning optimum seismic design and retrofit purposes, it is essential to predict the actual degree of seismic damage and SC capacity of PT rocking systems after seismic hazards. In this case, a self‐centering index (SI) is proposed to evaluate the SC capacity when piers are subjected to cyclic and seismic loadings. This SI, when used in co‐operation with a viable damage prediction model, predicts whether or not the piers remain reparable under cyclic or seismic loading scenarios. After comparing a number of energy‐based damage indices, all of which consider the cumulative hysteresis energy, with the input energy‐based damage index (IEB‐DI), the latter was calibrated against observed damages under cyclic loading tests. This DI was chosen as the most suitable damage prediction model and was considered to be simply applicable after time history analysis. In this study, the seismic performance of a seismic‐resistant dual system, consisting of three RC bents along with an SC bent, was evaluated using the aforementioned damage limit states and the introduced SI. The damage predictions of the monolithic bridge, as the reference model, were compared with the estimated damage to the dual bridge. The results show that the joint application of the IEB‐DI and the proposed SI in predicting the performance level of SC rocking piers results in a comprehensive damage prediction model.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"13 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226095","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}
Recycled aggregate concrete (RAC) is a multi‐phase material, and it is meaningful to investigate the effect of the properties of each phase. However, a comprehensive parametric analysis of these properties is still lacking, which limits a full understanding of the behavior of RAC. This paper uses numerical mesoscale models and contributes to knowledge on this topic. It focuses on the effects of the quality and shape of aggregate since they are relevant to the behavior of concrete but have scarcely been studied for RAC. Their effects on the mechanical response and fracture behavior of RAC were analyzed based on a validated two‐dimensional numerical model. In addition, this paper also justified the choice of the range of the parameters as well as benchmarked the numerical results with the state‐of‐the‐art. The main findings of the paper are: (1) stiffer aggregates decrease the tensile (by up to 29%) and compressive strength of RAC (by up to 7%); (2) aggregate shape moderately influences these properties by up to 10% and 8%; (3) the modulus of elasticity of RAC is considerably influenced by the stiffness of the aggregates (15%), while it is almost unaffected by the shape of the aggregates; (4) both stiffer and elongated aggregates tend to cause micro‐cracking in the interface and premature failure of concrete.
{"title":"Mesoscale modeling of recycled aggregate concrete: A parametric analysis of the quality and shape of aggregate","authors":"Qifan Ren, João Pacheco, Jorge de Brito","doi":"10.1002/suco.202400743","DOIUrl":"https://doi.org/10.1002/suco.202400743","url":null,"abstract":"Recycled aggregate concrete (RAC) is a multi‐phase material, and it is meaningful to investigate the effect of the properties of each phase. However, a comprehensive parametric analysis of these properties is still lacking, which limits a full understanding of the behavior of RAC. This paper uses numerical mesoscale models and contributes to knowledge on this topic. It focuses on the effects of the quality and shape of aggregate since they are relevant to the behavior of concrete but have scarcely been studied for RAC. Their effects on the mechanical response and fracture behavior of RAC were analyzed based on a validated two‐dimensional numerical model. In addition, this paper also justified the choice of the range of the parameters as well as benchmarked the numerical results with the state‐of‐the‐art. The main findings of the paper are: (1) stiffer aggregates decrease the tensile (by up to 29%) and compressive strength of RAC (by up to 7%); (2) aggregate shape moderately influences these properties by up to 10% and 8%; (3) the modulus of elasticity of RAC is considerably influenced by the stiffness of the aggregates (15%), while it is almost unaffected by the shape of the aggregates; (4) both stiffer and elongated aggregates tend to cause micro‐cracking in the interface and premature failure of concrete.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"40 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203988","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}
Reinforced concrete (RC) structures are mainly designed to withstand both static and dynamic loads. However, due to the highly nonlinear behavior of RC structures subjected to extreme dynamic loads, these structures have a very complex damage behavior under dynamic impact loading. In fact, current existing methods for damage‐simulation and prediction are generally based on either empirical data, simplified mechanical approaches or complex numerical simulations mainly using the finite element method. In this regard, empirical and semi‐empirical models can be considered to calculate the load‐bearing capacity in a simplified way with only a few input parameters. Hence, using current experimental test data, this paper aims to analyze and assess existing empirical and semi‐analytical approaches that are established in standards and guidelines. Accordingly, a functional relationship in terms of an impact factor is found. Based on the obtained results, different approaches are also developed to describe the resistance to projectile penetration of RC structures as well as the force interaction between projectile and RC structures.
{"title":"Reinforced concrete structures under hard projectile impact: penetration and perforation resistance","authors":"Pascal Distler, Lars Heibges, Hamid Sadegh‐Azar","doi":"10.1002/suco.202300143","DOIUrl":"https://doi.org/10.1002/suco.202300143","url":null,"abstract":"Reinforced concrete (RC) structures are mainly designed to withstand both static and dynamic loads. However, due to the highly nonlinear behavior of RC structures subjected to extreme dynamic loads, these structures have a very complex damage behavior under dynamic impact loading. In fact, current existing methods for damage‐simulation and prediction are generally based on either empirical data, simplified mechanical approaches or complex numerical simulations mainly using the finite element method. In this regard, empirical and semi‐empirical models can be considered to calculate the load‐bearing capacity in a simplified way with only a few input parameters. Hence, using current experimental test data, this paper aims to analyze and assess existing empirical and semi‐analytical approaches that are established in standards and guidelines. Accordingly, a functional relationship in terms of an impact factor is found. Based on the obtained results, different approaches are also developed to describe the resistance to projectile penetration of RC structures as well as the force interaction between projectile and RC structures.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"59 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203989","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}
This study utilized experimental research to investigate the efficiency of using normal aggregate concrete (NAC) or recycled aggregate concrete (RAC) as a new concrete layer for repairing projectile bullet damage to strengthening reinforced concrete (RC) beams. This study comprised the construction and testing of eight RC beams made of RAC and NAC. They are initially subjected to projectile bullets and after that tested with flexure load to evaluate the effect of using RAC and NAC that was investigated. The findings of test results demonstrate that the repaired specimens with RAC or NAC experienced a higher load capacity than the damaged control specimens. As such, this approach could potentially use to restore RAC or NAC beams were previously damaged by projectile bullets. In addition, the findings of this research indicate that the load capacity of the damaged RC beams that were previously repaired using the NAC layer was higher than the load capacity of the damaged RC beams that were repaired using the RAC layer. The load capacity enhanced significantly of (106%–118%) and (104%–113%), respectively, when NAC and RAC are utilized in repairs. Therefore, using either NAC or RAC concrete is more economical, environmentally friendly, and efficient than demolishing.
{"title":"Effect of using normal concrete or recycled concrete layer on behavior of repaired projectile bullet damaged reinforced concrete beams","authors":"Ala’ Taleb Obaidat","doi":"10.1002/suco.202301054","DOIUrl":"https://doi.org/10.1002/suco.202301054","url":null,"abstract":"This study utilized experimental research to investigate the efficiency of using normal aggregate concrete (NAC) or recycled aggregate concrete (RAC) as a new concrete layer for repairing projectile bullet damage to strengthening reinforced concrete (RC) beams. This study comprised the construction and testing of eight RC beams made of RAC and NAC. They are initially subjected to projectile bullets and after that tested with flexure load to evaluate the effect of using RAC and NAC that was investigated. The findings of test results demonstrate that the repaired specimens with RAC or NAC experienced a higher load capacity than the damaged control specimens. As such, this approach could potentially use to restore RAC or NAC beams were previously damaged by projectile bullets. In addition, the findings of this research indicate that the load capacity of the damaged RC beams that were previously repaired using the NAC layer was higher than the load capacity of the damaged RC beams that were repaired using the RAC layer. The load capacity enhanced significantly of (106%–118%) and (104%–113%), respectively, when NAC and RAC are utilized in repairs. Therefore, using either NAC or RAC concrete is more economical, environmentally friendly, and efficient than demolishing.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"70 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203990","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}
Using ultra‐high‐performance fiber‐reinforced concrete (UHPFRC) in profiled slabs, as opposed to normal strength concrete without fibers, has been shown experimentally to significantly increase both the bond between the profiled sheet and the concrete, and the tensile forces across cracked concrete. The consequence of these fiber benefits is to substantially increase the flexural rigidity leading to reduced deflections and also to substantially reduced crack widths leading to improved behavior under serviceability loads and to improved durability. To quantify these benefits so that they can be used in design, a rational partial‐interaction numerical model has been developed that can incorporate the material properties of any type of UHPFRC including time‐effects. This modeling should help in the development of simplified design rules for specific fiber types.
{"title":"Quantifying the serviceability flexural benefits of using UHPFRC in profiled slabs","authors":"S. Chen, P. Visintin, A. B. Sturm, D. J. Oehlers","doi":"10.1002/suco.202300389","DOIUrl":"https://doi.org/10.1002/suco.202300389","url":null,"abstract":"Using ultra‐high‐performance fiber‐reinforced concrete (UHPFRC) in profiled slabs, as opposed to normal strength concrete without fibers, has been shown experimentally to significantly increase both the bond between the profiled sheet and the concrete, and the tensile forces across cracked concrete. The consequence of these fiber benefits is to substantially increase the flexural rigidity leading to reduced deflections and also to substantially reduced crack widths leading to improved behavior under serviceability loads and to improved durability. To quantify these benefits so that they can be used in design, a rational partial‐interaction numerical model has been developed that can incorporate the material properties of any type of UHPFRC including time‐effects. This modeling should help in the development of simplified design rules for specific fiber types.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"24 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203991","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}
Martin Lipowczan, Lukáš Novák, David Lehký, Drahomír Novák
The paper portrays a comprehensive computational procedure for determining the global structural resistances of two existing bridges made of I‐73 and KA‐61 precast post‐tensioned concrete girders using advanced statistical assessment methods in combination with nonlinear fracture mechanics‐based finite element method analysis. Although this combination is a powerful tool for realistic modeling of structures, its practical application is still very time consuming. Therefore, a statistical sampling approach for the determination of the structural design resistance is compared to selected efficient semi‐probabilistic methods based on the estimation of coefficient of variation—estimation of coefficient of variation (ECoV) method according to fib Model Code 2010 and improved approach called Eigen ECoV method. Load‐bearing capacity is determined for the ultimate as well as several serviceability limit states. The sensitivity of the input parameters burdened with uncertainties on the response of the structure is quantified using a sensitivity analysis supported by a surrogate model based on polynomial chaos expansion. The paper shows that the applicability of nonlinear modeling with respect to uncertainties is possible when using these ECoV methods and a surrogate model and can be applied in a routine manner. The shortcomings and advantages of all the used safety design/assessment methods are discussed.
本文介绍了一种综合计算程序，该程序采用先进的统计评估方法，结合基于非线性断裂力学的有限元方法分析，确定了两座由 I-73 和 KA-61 预制后张法混凝土梁组成的现有桥梁的整体结构抗力。虽然这种组合是建立真实结构模型的有力工具，但其实际应用仍然非常耗时。因此，我们将用于确定结构设计阻力的统计抽样方法与基于变异系数估算--变异系数估算（ECoV）方法（根据 fib Model Code 2010 和改进方法 Eigen ECoV 方法）的选定高效半概率方法进行了比较。承载能力是根据极限状态和几种适用性极限状态确定的。使用基于多项式混沌扩展的代用模型支持的敏感性分析，量化了输入参数对结构响应的不确定性的敏感性。论文表明，在使用这些 ECoV 方法和代理模型时，可以对不确定性进行非线性建模，并且可以以常规方式应用。文中还讨论了所有使用的安全设计/评估方法的缺点和优点。
{"title":"Nonlinear global design resistance: Case studies of post‐tensioned concrete bridges made of I‐73 and KA‐61 girders","authors":"Martin Lipowczan, Lukáš Novák, David Lehký, Drahomír Novák","doi":"10.1002/suco.202300986","DOIUrl":"https://doi.org/10.1002/suco.202300986","url":null,"abstract":"The paper portrays a comprehensive computational procedure for determining the global structural resistances of two existing bridges made of I‐73 and KA‐61 precast post‐tensioned concrete girders using advanced statistical assessment methods in combination with nonlinear fracture mechanics‐based finite element method analysis. Although this combination is a powerful tool for realistic modeling of structures, its practical application is still very time consuming. Therefore, a statistical sampling approach for the determination of the structural design resistance is compared to selected efficient semi‐probabilistic methods based on the estimation of coefficient of variation—estimation of coefficient of variation (ECoV) method according to <jats:italic>fib</jats:italic> Model Code 2010 and improved approach called Eigen ECoV method. Load‐bearing capacity is determined for the ultimate as well as several serviceability limit states. The sensitivity of the input parameters burdened with uncertainties on the response of the structure is quantified using a sensitivity analysis supported by a surrogate model based on polynomial chaos expansion. The paper shows that the applicability of nonlinear modeling with respect to uncertainties is possible when using these ECoV methods and a surrogate model and can be applied in a routine manner. The shortcomings and advantages of all the used safety design/assessment methods are discussed.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"14 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203993","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 study examines the early incorporation of reinforced concrete in the architecture of Historicism in Austria–Hungary. Spanning the late 19th to early 20th centuries, the research illuminates the period's stylistic pluralism and the transformative impact of reinforced concrete. The paper examines the integration of reinforced concrete into traditional forms, providing detailed case studies and architectural examples. It navigates through various aspects, including the evolution of reinforced concrete during the historicist period, its adoption in notable structures, and its documentation in contemporary literature. Case studies, such as the Lutheran Church in Battyánd (now Puconci, Slovenia), the Roman Catholic Church in Topolya (now Bačka Topola, Serbia), and the former Synagogue in Český Krumlov, Czechia, showcase the innovative ways reinforced concrete addressed structural challenges while adhering to historicist aesthetics. The research concludes by reflecting on the transformative role of reinforced concrete in challenging the conventions of Historicism, paving the way for modern architectural expressions.
{"title":"Early use of the reinforced concrete in the architecture of the Historicism in Austria–Hungary","authors":"Éva Lovra, Zoltán Bereczki","doi":"10.1002/suco.202400160","DOIUrl":"https://doi.org/10.1002/suco.202400160","url":null,"abstract":"The study examines the early incorporation of reinforced concrete in the architecture of Historicism in Austria–Hungary. Spanning the late 19th to early 20th centuries, the research illuminates the period's stylistic pluralism and the transformative impact of reinforced concrete. The paper examines the integration of reinforced concrete into traditional forms, providing detailed case studies and architectural examples. It navigates through various aspects, including the evolution of reinforced concrete during the historicist period, its adoption in notable structures, and its documentation in contemporary literature. Case studies, such as the Lutheran Church in Battyánd (now Puconci, Slovenia), the Roman Catholic Church in Topolya (now Bačka Topola, Serbia), and the former Synagogue in Český Krumlov, Czechia, showcase the innovative ways reinforced concrete addressed structural challenges while adhering to historicist aesthetics. The research concludes by reflecting on the transformative role of reinforced concrete in challenging the conventions of Historicism, paving the way for modern architectural expressions.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"18 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203992","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}
Torkil Veyhe, Henrik Brøner Jørgensen, Søren Gustenhoff Hansen
Within the last decade, a construction‐friendly design principle using flexible wire ropes instead of traditional u‐bars for connecting wall elements has gained popularity. However, anchoring wire ropes in T and L connections remains a complex challenge. Here, the wire ropes stick out of the side of the wall element and are bent in the anchorage zone. This paper presents the findings of an extensive experimental program with 40 specimens, investigating the anchorage capacity of wire ropes in wall elements under these conditions. The study reveals that specially designed reinforcements significantly increase the anchorage capacity, while traditional wall reinforcements have minimal impact. Failure mechanisms primarily involve concrete cone failures, providing valuable insights for construction‐friendly connections. Based on the observed failure mechanism, the paper presents an analytical failure mechanism. The model is based on the upper‐bound theorem of plasticity theory. The model predicts both the capacity and the failure mechanism with satisfactory accuracy.
在过去十年中，使用柔性钢丝绳代替传统 U 型杆来连接墙体构件这一方便施工的设计原则得到了普及。然而，在 T 型和 L 型连接中锚固钢丝绳仍然是一项复杂的挑战。在这种情况下，钢丝绳会从墙体构件的侧面伸出，并在锚固区弯曲。本文介绍了使用 40 个试样进行广泛实验的结果，研究了钢丝绳在这些条件下在墙体构件中的锚固能力。研究结果表明，专门设计的加固件可显著提高锚固能力，而传统墙体加固件的影响则微乎其微。失效机理主要涉及混凝土锥体失效，为施工友好型连接提供了宝贵的见解。根据观察到的失效机理，本文提出了一种分析失效机理。该模型基于塑性理论的上界定理。该模型能准确预测承载能力和失效机理。
{"title":"Anchorage capacity of bent looped wire ropes in precast concrete wall elements for T‐ and L‐ connections","authors":"Torkil Veyhe, Henrik Brøner Jørgensen, Søren Gustenhoff Hansen","doi":"10.1002/suco.202400107","DOIUrl":"https://doi.org/10.1002/suco.202400107","url":null,"abstract":"Within the last decade, a construction‐friendly design principle using flexible wire ropes instead of traditional u‐bars for connecting wall elements has gained popularity. However, anchoring wire ropes in T and L connections remains a complex challenge. Here, the wire ropes stick out of the side of the wall element and are bent in the anchorage zone. This paper presents the findings of an extensive experimental program with 40 specimens, investigating the anchorage capacity of wire ropes in wall elements under these conditions. The study reveals that specially designed reinforcements significantly increase the anchorage capacity, while traditional wall reinforcements have minimal impact. Failure mechanisms primarily involve concrete cone failures, providing valuable insights for construction‐friendly connections. Based on the observed failure mechanism, the paper presents an analytical failure mechanism. The model is based on the upper‐bound theorem of plasticity theory. The model predicts both the capacity and the failure mechanism with satisfactory accuracy.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"37 4 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203994","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 understanding of the cyclic performance of reinforced concrete (RC) elements is of vital importance in relation to the extent of the service life of buildings and infrastructures. Steel rebar corrosion plays a major role in this regard because it significantly affects the overall structural integrity, especially under cyclic loads, leading to reduced stiffness and load‐bearing capacity of structural elements. Cyclic condition has the potential to accelerate the corrosion‐induced cracking and spalling, the effectiveness of the bond strength between rebar and concrete, and also the ductility and energy dissipation characteristics of the structure. The primary objective of this study is to investigate the effectiveness of a high‐performance thixotropic repairing cementitious mortar in improving the fatigue behavior of RC elements through a multiscale experimental approach. First, at the material scale of concrete specimens, two different concrete classes together with the repairing one‐component, pre‐blended, thixotropic cementitious mortar, were tested under incremental cyclic condition. Based on the results obtained from material scale, four reinforced concrete beams were exposed to different levels of accelerated corrosion by means of the impressed current technique and, subsequently, repaired by bonding a layer of the thixotropic high‐performance mortar onto the tension side. Finally, beams were tested under incremental cyclic four‐point bending test to investigate the fatigue behavior in terms of crack onset, propagation and energy dissipation. The resulting cyclic properties and cracking behavior of the structural elements were related to the level of corrosion achieved through the accelerated test and the effectiveness of the structural repair mortar was proven. In terms of code compliance, the repairing mortar was able to fulfill the requirements of frequent and quasi‐permanent combination of loads, remaining below all the threshold values provided by the Italian NTC2018 and Eurocode.
{"title":"Flexural behavior of corroded RC beams repaired with high performance cementitious mortar under cyclic loading","authors":"Antonio Mudadu, Andrea Prota, Costantino Menna","doi":"10.1002/suco.202400375","DOIUrl":"https://doi.org/10.1002/suco.202400375","url":null,"abstract":"The understanding of the cyclic performance of reinforced concrete (RC) elements is of vital importance in relation to the extent of the service life of buildings and infrastructures. Steel rebar corrosion plays a major role in this regard because it significantly affects the overall structural integrity, especially under cyclic loads, leading to reduced stiffness and load‐bearing capacity of structural elements. Cyclic condition has the potential to accelerate the corrosion‐induced cracking and spalling, the effectiveness of the bond strength between rebar and concrete, and also the ductility and energy dissipation characteristics of the structure. The primary objective of this study is to investigate the effectiveness of a high‐performance thixotropic repairing cementitious mortar in improving the fatigue behavior of RC elements through a multiscale experimental approach. First, at the material scale of concrete specimens, two different concrete classes together with the repairing one‐component, pre‐blended, thixotropic cementitious mortar, were tested under incremental cyclic condition. Based on the results obtained from material scale, four reinforced concrete beams were exposed to different levels of accelerated corrosion by means of the impressed current technique and, subsequently, repaired by bonding a layer of the thixotropic high‐performance mortar onto the tension side. Finally, beams were tested under incremental cyclic four‐point bending test to investigate the fatigue behavior in terms of crack onset, propagation and energy dissipation. The resulting cyclic properties and cracking behavior of the structural elements were related to the level of corrosion achieved through the accelerated test and the effectiveness of the structural repair mortar was proven. In terms of code compliance, the repairing mortar was able to fulfill the requirements of frequent and quasi‐permanent combination of loads, remaining below all the threshold values provided by the Italian NTC2018 and Eurocode.","PeriodicalId":21988,"journal":{"name":"Structural Concrete","volume":"143 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203995","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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