@incollection{SykoraHolickyJungetal., author = {S{\´y}kora, Miroslav and Holick{\´y}, Milan and Jung, Karel and Diamantidis, Dimitris}, title = {Target reliability levels for assessment of existing structures considering economic and societal aspects}, series = {Life-Cycle of Structural Systems}, booktitle = {Life-Cycle of Structural Systems}, editor = {Akiyama, Mitsuyoshi and Furuta, Hitoshi and Frangopol, Dan M.}, publisher = {CRC Press}, address = {London}, isbn = {9780429227196}, doi = {10.1201/b17618-121}, pages = {838 -- 845}, abstract = {Specification of the target reliability levels is one of the key issues of the assessment of existing structures. ISO 13822:2010 and ISO 2394:1998 indicate procedures for deriving the target reliability levels by optimisation of the total cost related to an assumed remaining working life of a structure. In the submitted study this approach is applied to estimate the target reliability levels of an existing structural member in conjunction with the human safety criteria. Obtained results are critically compared with the recommendations given in present standards. It appears that the requirement on the same target reliability levels for existing structures as for new structures is uneconomical. Further, the cost optimisation seems to yield rather low reliability levels and human safety criteria become commonly decisive for specification of the target reliabilities of existing structures.}, language = {en} } @inproceedings{SykoraDiamantidisMarkovaetal., author = {S{\´y}kora, Miroslav and Diamantidis, Dimitris and Markov{\´a}, Jana and Masciotta, Maria Giovanna}, title = {Optimizing in-situ testing for historic masonry structures: a case study}, series = {International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) : Durability, Monitoring and Repair of Structures, 20-22 March 2019, Rovinj, Croatia}, booktitle = {International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) : Durability, Monitoring and Repair of Structures, 20-22 March 2019, Rovinj, Croatia}, editor = {Baričević, Ana and Jelčić Rukavina, Marija and Damjanović, Domagoi and Guadagnini, Maurizio}, publisher = {RILEM Publications}, isbn = {978-1-5108-9296-5}, pages = {684 -- 691}, language = {en} } @article{OrcesiO'ConnorDiamantidisetal., author = {Orcesi, Andr{\´e} and O'Connor, Alan and Diamantidis, Dimitris and S{\´y}kora, Miroslav and Wu, Teng and Akiyama, Mitsuyoshi and Alhamid, Abdul Kadir and Schmidt, Franziska and Pregnolato, Maria and Li, Yue and Salarieh, Babak and Salman, Abdullahi M. and Bastidas-Arteaga, Emilio and Markogiannaki, Olga and Schoefs, Franck}, title = {Investigating the Effects of Climate Change on Structural Actions}, series = {Structural Engineering International}, volume = {32}, journal = {Structural Engineering International}, number = {4}, publisher = {Taylor \& Francis}, doi = {10.1080/10168664.2022.2098894}, pages = {1 -- 14}, abstract = {The changing climate with resulting more extreme weather events will likely impact infrastructure assets and services. This phenomenon can present direct threats to the assets as well as significant indirect effects for those relying on the services those assets deliver. Such threats are path-dependent and place-specific, as they strongly depend on current and future climate variability, location, asset design life, function and condition. One key question is how climate change is likely to increase both the probability and magnitude of extreme weather events under different scenarios of climate change. To address this issue, this paper investigates selected effects of climate change and their consequences on structural performance, in the context of evolving loading scenarios in three different continental regions: Europe, North America, and Asia. The aim is to investigate some main place-specific changes of the exposure in terms of intensity/frequency of extreme events as well as the associated challenges, considering some recent activities of members of the IABSE TG6.1. Climate change can significantly affect built infrastructure and the society by increasing the occurrence and magnitude of extreme events and increasing potential losses. Therefore, specific relationships relating hazard levels and structural vulnerability to climate change effects should be determined.}, language = {en} } @article{OrcesiDiamantidisO’Connoretal., author = {Orcesi, Andr{\´e} and Diamantidis, Dimitris and O'Connor, Alan and Palmisano, Fabrizio and S{\´y}kora, Miroslav and Boros, Vazul and Caspeele, Robby and Chateauneuf, Alaa and Mandić Ivanković, Ana and Lenner, Roman and Kušter Marić, Marija and Nadolski, Vitali and Schmidt, Franziska and Skokandić, Dominik and van der Spuy, Pierre}, title = {Investigating Partial Factors for the Assessment of Existing Reinforced Concrete Bridges}, series = {Structural Engineering International}, journal = {Structural Engineering International}, publisher = {Taylor \& Francis}, doi = {10.1080/10168664.2023.2204115}, pages = {1 -- 16}, abstract = {There is great interest in developing an adequate partial factor format for the assessment of existing structures, and in particular bridges, that should be able to take various aspects into account linked to the fact that the structure already exists. As the structure is existing, additional information related to material parameters, loading conditions, local structural defects, etc. can be accounted for. In addition, the degree of conservatism needs to be well balanced to avoid unnecessary investment of resources in replacement or retrofitting. This contribution considers the experience gained in recent years in parallel with some ongoing standardisation work in relation to Eurocodes and the next edition of the fib Model Code for new and existing concrete structures. The current state of the art of partial factors for the assessment of existing structures is explored and the differences are assessed based on a comparison between (i) the use of recommended fixed partial factors as provided in many national and international codes, (ii) adjusted (flexible) partial factors derived for the individual case under consideration, and (ii) reliability-based verification. In order to assess the adequacy of proposals and identify some differences, the available partial factor formats are applied to two case studies of reinforced concrete bridges and they are critically assessed.}, language = {en} } @inproceedings{SykoraNadolskiNovaketal., author = {Sykora, Miroslav and Nadolski, Vitali and Novak, Luk{\´a}š and Novak, Drahom{\´i}r and Diamantidis, Dimitris}, title = {Pilot comparison of semi-probabilistic methods applied to RC structures with multiple failure modes}, series = {Concrete Innovation for Sustainability, 6th fib International Congress in Oslo, Norway (2022), proceedings, 12-16 June 2022, Oslo, Norway}, booktitle = {Concrete Innovation for Sustainability, 6th fib International Congress in Oslo, Norway (2022), proceedings, 12-16 June 2022, Oslo, Norway}, publisher = {fib}, pages = {1890 -- 1899}, language = {en} } @inproceedings{OrcesiBastidasArteagaMarkogiannakietal., author = {Orcesi, Andre and Bastidas-Arteaga, Emilio and Markogiannaki, Olga and Li, Yue and Schoefs, Franck and Ballester, Jorge and O'Connor, Alan and S{\´y}kora, Miroslav and Imam, Boulent and Pregnolato, Maria and Stewart, Mark and Ryan, Paraic and Diamantidis, Dimitris and Wu, Teng and Schmidt, Franziska and Kreislov{\´a}, Kateřina and Salman, Abdullahi M.}, title = {Investigating the effects of climate change on structural resistance and actions}, series = {IABSE Congress, Ghent 2021, Structural Engineering for Future Societal Needs: 22.02.2021 - 24.02.2021, Ghent, Belgium}, booktitle = {IABSE Congress, Ghent 2021, Structural Engineering for Future Societal Needs: 22.02.2021 - 24.02.2021, Ghent, Belgium}, publisher = {International Association for Bridge and Structural Engineering (IABSE)}, address = {Z{\"u}rich}, doi = {10.2749/ghent.2021.0974}, pages = {974 -- 985}, abstract = {One major issue when considering the effects of climate change is to understand, qualify and quantify how natural hazards and the changing climate will likely impact infrastructure assets and services as it strongly depends on current and future climate variability, location, asset design life, function and condition. So far, there is no well-defined and agreed performance indicator that isolates the effects of climate change for structures. Rather, one can mention some key considerations on how climate change may produce changes of vulnerability due to physical and chemical actions affecting structural durability or changes of the exposure in terms of intensity/frequency of extreme events. This paper considers these two aspects and associated challenges, considering some recent activities of members of the IABSE TG6.1.}, language = {en} } @article{PandeyViljoenWayetal., author = {Pandey, Mahesh and Viljoen, Celeste and Way, Andrew and Katharina Fischer, Katharina and S{\´y}kora, Miroslav and Diamantidis, Dimitris and Steenbergen, Rapha{\"e}l D.J.M. and Lind, Niels and Frangopol, Dan M. and Yang, David Y. and Retief, Johan Verster and Andr{\´e}, Jo{\~a}o and Nathwani, Jatin and Lenner, Roman}, title = {Life safety in the Reliability-Based design and assessment of structures}, series = {Structural Safety}, journal = {Structural Safety}, publisher = {Elsevier}, doi = {10.1016/j.strusafe.2024.102453}, abstract = {We review the developments in life safety and the incorporation thereof in the design and assessment of structures over the last 50 years. Various measures of life safety are presented that have been developed according to the marginal life saving cost principle based on individual, societal and economic considerations. Target probabilities of failure, or target reliabilities, are central to modern structural design and assessment. These are derived either through back-calibration to existing practice or through life cycle cost minimisation, both of which yield comparable safety levels, and are underpinned by lower bounds from life safety. Life cycle cost minimisation is reviewed here, which considers all direct and indirect costs of failure including loss of life and limb, as well as the costs and efficiency of increasing reliability. We discuss the incorporation of life safety into reliability-based design and assessment through the concept of the Life Quality Index, which uses key societal indicators, namely, the GDP and life expectancy, and health economics as a basis for specifying minimum reliabilities for both new and existing structures. The current state of advancement of reliability- and risk-informed design, and recommendations for future developments in life safety are considered.}, language = {en} } @article{DiamantidisTannerHolickyetal., author = {Diamantidis, Dimitris and Tanner, Peter and Holicky, Milan and Madsen, Henrik O. and Sykora, Miroslav}, title = {On reliability assessment of existing structures}, series = {Structural Safety}, journal = {Structural Safety}, publisher = {Elsevier}, issn = {0167-4730}, doi = {10.1016/j.strusafe.2024.102452}, pages = {1}, abstract = {This contribution discusses the reliability assessment of existing structures emphasizing on developments within or initiated by the JCSS. After a bibliographical review, the principles of reliability updating, i.e. Bayesian updating of random variables and updating of event probabilities are summarized. Developments in standards and established verification formats—partial factor or load and resistance factor, reliability-based, and risk-informed—are briefly presented and discussed. The impact of JCSS work in recent standards such as ISO 13822, the draft Eurocode prEN1990-2, and the fib Model Code 2020 as well as in national standards is highlighted. Criteria for defining target reliabilities for existing structures including human safety and optimization are critically reviewed. Obstacles for a wider implementation of reliability-based and risk-informed methods in practice are identified and conclusions for future developments are drawn. Finally, Annex A illustrates updating procedures for resistance variables and Annex B presents a case study.}, language = {en} }