TY - JOUR AU - Kövesdi, Balázs Géza AU - Kollár, Dénes AU - Szabó, B. AU - Dunai, László TI - Probabilistic failure assessment of steel eyebars by considering multi-phase nonlinear corrosion model JF - JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH J2 - J CONSTR STEEL RES VL - 224 PY - 2025 IS - Part A PG - 12 SN - 0143-974X DO - 10.1016/j.jcsr.2024.109127 UR - https://m2.mtmt.hu/api/publication/35509937 ID - 35509937 N1 - Export Date: 22 November 2024 Correspondence Address: Kollár, D.; Department of Structural Engineering, Műegyetem rkp. 3., Hungary; email: kollar.denes@emk.bme.hu Funding details: Marine Stewardship Council, MSC Funding details: Magyar Tudományos Akadémia, MTA, ÚNKP-23-1-I-BME-198 Funding details: Magyar Tudományos Akadémia, MTA Funding text 1: The presented research program has been partly financially supported by the Grant MTA-BME Lend\\u00FClet LP2021-06/2021 \\u201CTheory of new generation steel bridges\\u201D program of the Hungarian Academy of Sciences , and by the Grant \\u00DANKP-23-1-I-BME-198 of the New National Excellence Program provided by the Ministry of Culture and Innovation of Hungary ; the financial supports are gratefully acknowledged. Funding text 2: The presented research program has been partly financially supported by the Grant MTA-BME Lend\\u00FClet LP2021-06/2021 \\u201CTheory of new generation steel bridges\\u201D program of the Hungarian Academy of Sciences, and by the Grant \\u00DANKP-23-1-I-BME-198 of the New National Excellence Program provided by the Ministry of Culture and Innovation of Hungary; the financial supports are gratefully acknowledged. The authors would like to express special thanks to the Designers (F\\u0151mterv Co. and MSC Ltd. design offices) of the bridge reconstruction for their cooperation within the expertizing tasks and evaluation of the on-site measurements. Special thanks are given also to the A-H\\u00EDd Co. who executed the reconstruction work of the bridge and provided the opportunity to execute the on-site measurements and gave always strong technical supports. LA - English DB - MTMT ER - TY - JOUR AU - Gu, Hao’an AU - Zhang, Xin AU - Sumarac, Dragoslav AU - Peng, Jiayi AU - Dunai, László AU - Zhang, Yufeng TI - Investigation of Separating Temperature-Induced Structural Strain Using Improved Blind Source Separation (BSS) Technique JF - SENSORS J2 - SENSORS-BASEL VL - 24 PY - 2024 IS - 24 PG - 20 SN - 1424-8220 DO - 10.3390/s24248015 UR - https://m2.mtmt.hu/api/publication/35667978 ID - 35667978 N1 - Export Date: 7 January 2025 Correspondence Address: Zhang, Y.; The State Key Laboratory for the Safety, China; email: kolya@jsti.com Funding details: BE2021021 Funding details: BA2022009, BZ2023011 Funding details: BK20240610 Funding text 1: This research was funded by the Project of Industry Foresight and Key Core Technologies grant number BE2021021, the Special Project on Transformation of Scientific and Technological Achievements in Jiangsu Province grant number BA2022009, the Jiangsu-Czech Bilateral Co-funding R&D Project grant number BZ2023011, and the Youth Scientists Projects of the Basic Research in Jiangsu Province grant number BK20240610. The APC was funded by the Project of Industry Foresight and Key Core Technologies grant number BE2021021, the Special Project on Transformation of Scientific and Technological Achievements in Jiangsu Province grant number BA2022009. AB - The strain data acquired from structural health monitoring (SHM) systems of large-span bridges are often contaminated by a mixture of temperature-induced and vehicle-induced strain components, thereby complicating the assessment of bridge health. Existing approaches for isolating temperature-induced strains predominantly rely on statistical temperature–strain models, which can be significantly influenced by arbitrarily chosen parameters, thereby undermining the accuracy of the results. Additionally, signal processing techniques, including empirical mode decomposition (EMD) and others, frequently yield unstable outcomes when confronted with nonlinear strain signals. In response to these challenges, this study proposes a novel temperature-induced strain separation technique based on improved blind source separation (BSS), termed the Temperature-Separate Second-Order Blind Identification (TS-SOBI) method. Numerical verification using a finite element (FE) bridge model that considers both temperature loads and vehicle loads confirms the effectiveness of TS-SOBI in accurately separating temperature-induced strain components. Furthermore, real strain data from the SHM system of a long-span bridge are utilized to validate the application of TS-SOBI in practical engineering scenarios. By evaluating the remaining strain components after applying the TS-SOBI method, a clearer understanding of changes in the bridge’s loading conditions is achieved. The investigation of TS-SOBI introduces a novel perspective for mitigating temperature effects in SHM applications for bridges. © 2024 by the authors. LA - English DB - MTMT ER - TY - JOUR AU - Olosz, Adél AU - Kövesdi, Balázs Géza AU - Hegyi, Péter AU - Dunai, László TI - Improvement of Stockbridge Damper Design for Cable-Stayed Bridges JF - APPLIED MECHANICS J2 - APPLI MECH VL - 5 PY - 2024 IS - 4 SP - 818 EP - 838 PG - 21 SN - 2673-3161 DO - 10.3390/applmech5040046 UR - https://m2.mtmt.hu/api/publication/35593680 ID - 35593680 AB - Stockbridge dampers are widely used to mitigate the vibrations of cable-stayed bridges and of many other cable-suspended or cable structures exposed to the action of pedestrians, traffic or wind load. Within the current research work, one of the most effective and likely used damper types, the Stockbridge damper, was investigated to support its design and application within the daily engineering praxis. The Stockbridge damper has a relatively simple structural layout, which ensures its modular design allows it to easily adapt the damper to cables having different dynamic properties (eigenfrequencies, mass, etc.). This paper focuses on two main research areas: (i) to understand the static and dynamic behaviour of the damper and the stay cable interaction to investigate the effectiveness of its damping; (ii) to study the sensitivity of the natural frequencies of the damper to the design parameters. The final aim of the research is to develop a simple design method that is easy to apply in engineering practice and allows the efficient adaptation of the Stockbridge damper to different cable-stayed bridges. Key findings include the recommendation to position the damper at approximately 20% of the cable length for optimal attenuation, the importance of detuning to maintain effectiveness under varying cable forces, and the observation that increasing the damper mass improves efficiency, particularly for detuned elements. LA - English DB - MTMT ER - TY - CHAP AU - Kövesdi, Balázs Géza AU - Kollár, Dénes AU - Dunai, László AU - Hodik, Z. ED - Jensen, J.S. ED - Frangopol, D.M. ED - Schmidt, J.W. TI - Risk assessment of the K-bridge over the Danube T2 - Bridge Maintenance, Safety, Management, Digitalization and Sustainability PB - CRC Press/Balkema CY - Boca Raton, Florida SN - 9781003483755 PY - 2024 SP - 3231 EP - 3239 PG - 9 DO - 10.1201/9781003483755-383 UR - https://m2.mtmt.hu/api/publication/35172394 ID - 35172394 N1 - Department of Structural Engineering, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, Hungary Budapest Közút Co, Budapest, Hungary Conference code: 315019 Export Date: 16 August 2024 Funding details: Magyar Tudományos Akadémia, MTA Funding text 1: The authors would like to express special thanks to the members of the group of experts (Adri\\u00E1n Horv\\u00E1th, Gyula Kolozsi, Zolt\\u00E1n M\\u00FCller and Zsolt Nagy) for their cooperation within the expertizing tasks and evaluation of on-site measurements and risk analysis results. The presented research program is also supported by the Grant MTA-BME Lend\\u00FClet LP2021-06/ 2021 \\u201CTheory of new generation steel bridges\\u201D program of the Hungarian Academy of Sciences, the support is gratefully acknowledged. The authors dedicate the paper to the memory of their colleague, Zolt\\u00E1n M\\u00FCller, who tragically died in 2023, with whom this was their last joint bridge inspection work. AB - The K-bridge spans over the Danube between Buda and the Hajógyári Island in Budapest, Hungary. The originally railway, recently mixed road and pedestrian bridge have a more than 70-year-old steel truss main girder with a span of 98.04 m and a steel-concrete deck system. It plays an important role in Budapest city life and is heavily used during the Sziget festival, one of the biggest festivals in Europe. In 2022, during the regular bridge inspection, heavy corrosion and material loss were found by the experts in the bridge deck system and on the steel cantilever beams under the pedestrian walkways. The Budapest University of Technology and Economics (BME), Department of Structural Engineering together with design and maintenance experts investigated the condition of the structure and made a probabilistic analysis to verify the resistance of the corroded structure and made the risk assessment before the organization of the Sziget festival. The main aim of the analysis was the assessment of the load-bearing capacity of the corroded structure and determination of its risk against possible failure, based on the survey results of the current corrosion condition. Detailed inspection, on-site geometrical and corrosion measurements and partial loading tests were executed on the structure, which results served as input data of the probabilistic analysis. Advanced numerical models are developed to accurately calculate the load-bearing capacity of the heavily damaged structural details of the bridge by using stochastic analysis combining geometrical and material nonlinear analysis using imperfections (GMNIA). Based on the investigations, the necessary short-term and long-term maintenance tasks could be identified to be carried out on the bridge to ensure safe operation of the structure during the Sziget festival and to prolong the service lifetime of the bridge. © 2024 The Author(s). LA - English DB - MTMT ER - TY - JOUR AU - Király, Krisztián AU - Dunai, László AU - Calado, Luis AU - Kocsis, András Balázs TI - Push-out tests of demountable shear connectors for sustainable composite structures JF - STEEL CONSTRUCTION-DESIGN AND RESEARCH J2 - STEEL CONSTR DES RES VL - 17 PY - 2024 IS - 4 SP - 200 EP - 211 PG - 12 SN - 1867-0520 DO - 10.1002/stco.202300044 UR - https://m2.mtmt.hu/api/publication/35172374 ID - 35172374 N1 - Budapest University of Technology and Economics, Department of Structural Engineering, Műegyetem rkp. 3, Budapest, H-1111, Hungary Universidade de Lisboa, CERIS, Instituto Superior Técnico, Av. Rovisco Pais 1, Lisbon, 1049-001, Portugal bim.GROUP Ltd., Lechner Ödön fasor 10/B, Budapest, H-1095, Hungary Export Date: 16 August 2024 Correspondence Address: Király, K.; Budapest University of Technology and Economics, Műegyetem rkp. 3, Hungary; email: kiraly.krisztian@emk.bme.hu Funding details: Central European University Budapest Foundation, CEUBF Funding details: Iing Co., Ltd. Funding details: Ministry of Innovation, MOI Funding details: National Research, Development and Innovation Office Funding text 1: The presented research work is being conducted with the cooperation of the Budapest University of Technology and Economics and K\\u00C9SZ Group, bim.GROUP Ltd., Hungary, and supported by the \\u00DANKP\\u201023\\u20103\\u2010II\\u2010BME\\u201091 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund. The assistance and help of the colleagues from the university and the company are highly appreciated. Special thanks to the colleagues of the fabricators and the laboratories, mainly to Dr. Mansour Kachichian, for their valuable help in the experimental programme. AB - The demountable shear connector is the most important component of sustainable composite structures, as it allows the elements to be reused. The ongoing research and development project – in the cooperation of the Budapest University of Technology and Economics and KÉSZ Group, bim.GROUP Ltd., Hungary – aims to design a new demountable steel-concrete composite structural system. In the current research, bolted shear connectors with embedded bolts and threaded rods, which can fit the applied technology of the industrial partner, are being developed and studied. One of the main aspects of this connection is to consider the bolt hole clearance – to decrease initial slip and stiffness reduction – and also to provide the proper strength and ductility features. A push-out experimental programme was designed and completed to study the behaviour of the developed shear connections. It is observed that the examined shear connectors have proper structural behaviour with adequate resistance and ductility, which is applicable according to the Eurocode 4 standard and fits the objectives of the current research project. This paper presents the developed structural details, the observations and the evaluation of the push-out experimental results with the conclusions and statements. © 2024 The Authors. Published by Ernst & Sohn GmbH. LA - English DB - MTMT ER - TY - JOUR AU - Wei, Qingyang AU - Kövesdi, Balázs Géza AU - Dunai, László AU - Cao, Maosen TI - Formulation of dynamic damage features sensitive to local fatigue cracks in steel bridges: Numerical study JF - STRUCTURES J2 - STRUCTURES VL - 67 PY - 2024 PG - 17 SN - 2352-0124 DO - 10.1016/j.istruc.2024.107049 UR - https://m2.mtmt.hu/api/publication/35166747 ID - 35166747 N1 - College of Mechanics and Engineering Science, Hohai University, Nanjing, China Department of Structural Engineering, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, Hungary Export Date: 26 August 2024 Correspondence Address: Cao, M.8 Focheng West Road, China; email: cmszhy@hhu.edu.cn Funding details: Magyar Tudományos Akadémia, MTA Funding details: Major International Joint Research Programme, 202112003 Funding details: Major International Joint Research Programme Funding details: Jiangsu Provincial Key Research and Development Program, BZ2022010 Funding details: Jiangsu Provincial Key Research and Development Program Funding text 1: The presented research program has been financially supported by the Grant MTA-BME Lend\\u00FClet LP2021-06 / 2021 \\u201CTheory of new generation steel bridges\\u201D program of the Hungarian Academy of Sciences. The Nanjing International Joint Research and Development Program No. 202112003 is also gratefully acknowledged. Funding text 2: The presented research program has been financially supported by the Grant MTA-BME Lend\\u00FClet LP2021\\u201306 / 2021 \\u201CTheory of new generation steel bridges\\u201D program of the Hungarian Academy of Sciences. The Nanjing International Joint Research and Development Program No. 202112003, and the Jiangsu International Joint Research and Development Program No. BZ2022010 are also gratefully acknowledged. LA - English DB - MTMT ER - TY - JOUR AU - Wei, Qingyang AU - Shen, Lei AU - Dunai, László AU - Kövesdi, Balázs Géza AU - Elqudah, Sara AU - Cao, Maosen TI - Quantitative evaluation on the effects of the spatial variability in concrete materials on seismic damage of concrete gravity dams JF - ENGINEERING FRACTURE MECHANICS J2 - ENG FRACT MECH VL - 307 PY - 2024 PG - 26 SN - 0013-7944 DO - 10.1016/j.engfracmech.2024.110287 UR - https://m2.mtmt.hu/api/publication/35092889 ID - 35092889 N1 - College of Mechanics and Engineering Science, Hohai University, Nanjing, China Department of Structural Engineering, Budapest University of Technology and Economics, Budapest, Hungary College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, China Jiangxi Province Key Laboratory of Environmental Geotechnical Engineering and Hazards Control, Jiangxi University of Science and Technology, Ganzhou, China Export Date: 19 July 2024 CODEN: EFMEA Correspondence Address: Cao, M.Focheng West Road 8, China; email: cmszhy@hhu.edu.cn Funding details: BZ2022010, BZ2023011 Funding details: Fundamental Research Funds for the Central Universities, B220204002 Funding details: Fundamental Research Funds for the Central Universities Funding text 1: The authors are grateful for the Jiangsu International Joint Research and Development Program (No. BZ2022010), the Jiangsu-Czech Bilateral Co-Funding R&D Project (No. BZ2023011), and the Fundamental Research Funds for the Central Universities (No. B220204002). LA - English DB - MTMT ER - TY - PAT AU - Csohány, András AU - Medveczki, István AU - Dunai, László AU - Pál, Gábor AU - Gosztola, Dániel AU - Hegyi, Péter AU - Kemenczés, András AU - Kollár, László Péter AU - Kövesdi, Balázs Géza TI - Javított tulajdonságú rezgéscsillapító egység feszített kábelekhez, különösen hídkábelekhez CY - Country:10001(1) PY - 2024 UR - https://m2.mtmt.hu/api/publication/35080955 ID - 35080955 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Wei, Qingyang AU - Kövesdi, Balázs Géza AU - Cao, Maosen AU - Dunai, László TI - Analysis of dynamic features on local fatigue cracks in steel bridges JF - PROCEDIA STRUCTURAL INTEGRITY J2 - PROCEDIA STRUCT INTEGRITY VL - 57 PY - 2024 SP - 262 EP - 270 PG - 9 SN - 2452-3216 DO - 10.1016/j.prostr.2024.03.028 UR - https://m2.mtmt.hu/api/publication/34839813 ID - 34839813 N1 - College of Mechanics and Materials, Hohai University, Focheng west road 8, Nanjing, 211100, China Department of Structural Engineering, Budapest University of Technology and Economics, Muegyetem rkp. 3, Budapest, 1111, Hungary Conference code: 199400 Export Date: 31 May 2024 Correspondence Address: Kövesdi, B.; Department of Structural Engineering, Muegyetem rkp. 3, Hungary; email: kovesdi.balazs@emk.bme.hu Funding details: Magyar Tudományos Akadémia, MTA Funding details: 202206710059 Funding text 1: This work was financially supported by the Grant MTA-BME Lend\\u00FClet LP2021-06 / 2021 "Theory of new generation steel bridges" program of the Hungarian Academy of Sciences, which is gratefully acknowledged. The authors are also grateful to the China Scholarship Council program (No. 202206710059), which also provided financial support to the research work. AB - In steel bridges with orthotropic decks, a common and important engineering structure, fatigue cracks can appear under long-term operation. Existing artificial detection is the main approach to detecting fatigue cracks in steel bridges, in addition to some non-destructive testing or image processing methods, and unmanned aerial vehicle are applied to improve accuracy and efficiency. However, the detection of fatigue cracks in steel bridges based on the variation of dynamic responses or dynamic parameters is another attractive idea, which is still rarely mentioned and investigated in the international literature. The reason is that local cracks usually have negligible effect on the global dynamic characteristics of steel bridges, resulting in the insensitivity to dynamic indexes to fatigue cracks. On this occasion, this study numerically explores and establishes two sensitive damage features to local damage, i.e., the crack in the vertical rib, based on the fatigue cracks found on the Türr Istvan bridge over the Danube River in Hungary. The local vibrations of the bridge are excited through the local impact on the structural details, i.e., the vertical rib, and then the high-order frequencies of the entire bridge are examined. The obtained high-order frequencies are proved to be more sensitive to the fatigue cracks on vertical ribs and increased with the crack depths. On the other hand, the correlation of the stress curves on opposite sides of the crack is sensitive to the depth of the crack. If fatigue cracks are found, the development degree of the fatigue cracks can be monitored more accurately by focusing on the correlation of local stresses near the crack. These two damage features are numerically proven to have feasibility and are expected to break through the insensitivity of the existing dynamic detection methods. © 2024 The Authors. Published by Elsevier B.V. LA - English DB - MTMT ER - TY - JOUR AU - Király, Krisztián AU - Dunai, László TI - Experimental Study of Novel Demountable Shear Connectors for Steel-concrete Composite Buildings JF - PERIODICA POLYTECHNICA-CIVIL ENGINEERING J2 - PERIOD POLYTECH CIV ENG VL - 68 PY - 2024 IS - 2 SP - 647 EP - 656 PG - 10 SN - 0553-6626 DO - 10.3311/PPci.22732 UR - https://m2.mtmt.hu/api/publication/34727225 ID - 34727225 N1 - Export Date: 5 April 2024 Correspondence Address: Király, K.; Department of Structural Engineering, Műegyetem rkp. 3., Kmf. 85, Hungary; email: kiraly.krisztian@emk.bme.hu AB - Sustainable composite structures in building construction are assembled using demountable structural elements that can be reused in the circular economy. The current research and development project, in cooperation with Budapest University of Technology and Economics and KeSZ Group, bim.GROUP Ltd., Hungary, aims to design a novel demountable steel-concrete composite slab and frame system for buildings. The key component of this construction is the demountable shear connector. In the current research, novel bolted shear connectors with embedded bolts and threaded rods are developed and studied that can fit the applied technology of the industrial partner. One of the leading aspects of this connection is the consideration of bolt hole clearance, since it occurs initial slip and stiffness reduction of the composite beam. In the first phase of the research program, demountable and economical structural details were developed, which can reduce the stiffness reduction with the proper resistance and ductility features. To study the behavior of these shear connections, a push-out experimental program was designed and completed in March and April 2023. It is observed that novel shear connectors have a proper behavior with sufficient resistance and ductility, which is applicable according to the Eurocode 4 standard and fits the objectives of the research and development project. In the paper, the developed structural details and the push-out experimental program are presented with general results and statements besides a detailed evaluation of a specified specimen type. LA - English DB - MTMT ER -