TY - CHAP A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Optimizing Monitoring - Implementation of Draft Guideline and Case Study of Roof Exposed to Snow Loads T2 - Proceedings of 40th IABSE Symposium : Tomorrow's Megastructures, Nantes, France, 19-21 September 2018 N2 - This contribution addresses the optimisation of monitoring and decision-making criteria regarding the future use of structures and the related implementation in modern guidelines. A summary of the state-of-practice reveals deficiencies that are addressed by prospective guidance for the anticipated updates of standards, providing a general methodology to obtain cost-optimal decisions using limit state design, probabilistic reliability analysis and cost estimates. The implementation of a draft guideline and the corresponding risk-based approach are illustrated in a full-scale case study dealing with the roof of a stadium located in Northern Italy. The results demonstrate the potential of using monitoring systems and probabilistic reliability analysis in order to support decisions regarding safety measures such as snow removal, or temporary closure of the stadium. KW - cost optimisation KW - decision making criteria KW - Eurocodes KW - monitoring KW - reliability analysis KW - snow load KW - stadium roof KW - standard Y1 - 2018 SN - 978-3-85748-161-1 U6 - https://doi.org/10.2749/nantes.2018.s27-27 PB - Curran Associates Inc CY - Red Hook, NY ER - TY - CHAP A1 - Diamantidis, Dimitris A1 - Holický, Milan A1 - Sýkora, Miroslav T1 - Target Reliability Levels Based on Societal, Economic and Environmental Consequences of Structural Failure T2 - Proceedings of the 12th International Conference on Structural Safety & Reliability (ICOSSAR 2017), 6-10 August 2017, Vienna, Austria N2 - Target reliability levels are derived by optimizing initial structural costs and considering three major types of potential consequences of structural failure: a) direct and indirect economic losses, b) societal consequences resulting from fatalities and injuries, and c) environmental impacts. The guidance on how to e stimate and combine these consequences is provided; societal consequences are expressed using the Life Quality Index (LQI) concept. The case study focused on a generic load-bearing member reveals that target reliability levels for structural design are commonly dominated by economic criteria. Y1 - 2017 UR - https://www.researchgate.net/publication/319123444_Target_Reliability_Levels_Based_on_Societal_Economic_and_Environmental_Consequences_of_Structural_Failure ER - TY - CHAP A1 - Holický, Milan A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Effects of Quality Control on Reliability of Reinforced Concrete Structures according to Eurocodes T2 - fib Symposium 2016 : Performance-Based Approaches for Concrete Structures, 14, 2016, Cape town N2 - The effect of quality control on structural reliability represents an increasingly important concern of designers and thus is investigated in this contribution, focusing on reinforced concrete structures. Recent European documents for structural design – Eurocodes, fib Model Code 2010 and ISO 2394:2015 for general principles on structural reliability indicate that the partial factors may be adjusted to available information on the quality control of structures. In particular, the partial factors for concrete and steel strength may be significantly reduced taking into account actual execution quality and related available data. Using probabilistic methods of structural reliability, effects for execution quality are investigated in this contribution considering two fundamental reinforced concrete members: a beam (or slab) exposed to bending and a short column exposed to compression. It is shown that the reliability of reinforced concrete members may vary with the load ratio of variable and permanent actions. It appears also that the structural members of a basic quality, designed using unreduced partial factors, have a greater reliability level than the members of an increased quality, designed using the partial factors reduced according to EN 1992 1 1. This provides the basis for recommendations for further code developments. KW - Eurocodes KW - partial factors KW - quality control KW - reliability Y1 - 2016 UR - https://www.researchgate.net/publication/310616676_Effects_of_quality_control_on_reliability_of_reinforced_concrete_structures_according_to_Eurocodes ER - TY - CHAP A1 - Mühlbauer, Simon A1 - Diamantidis, Dimitris A1 - Schneider, Josef T1 - Seismic Assessment and Retrofitting Of Damaged Quarry Stone Buildings in Nepal T2 - Proceedings of 2nd the International Conference on Civil Engineering Fundamentals and Applications (ICCEFA'21): Virtual Conference - November 21 - 23, 2021 N2 - The scope of this contribution is to provide and analyse a rehabilitation concept for typical brick residential buildings in Nepal damaged after the spring 2015 earthquake of magnitude 7.8. Development workers of Engineers Without Borders Germany travelled the same year to the village of Lurpung, southeast of Kathmandu to inspect damages and recommended primary approaches for the earthquake-resistant reconstruction of residential buildings [1]. A detailed restructuring concept is developed herein based on the aforementioned recommended approaches and optimized in terms of time and cost based on information reflecting site conditions and experience. For this purpose, a horizontal timber bracing has been designed, which consists to a large extent of local existing materials. It is demonstrated that the strengthening can be applied in an area of high seismic activity and to simple quarry stone masonry buildings typical for Nepal. In a first stage, a detailed FE-model was developed, focusing on a realistic load-bearing behaviour of a representative typical structure. Thereby it is ensured that the most accurate internal forces and stresses can be obtained from the FEM analyses for further verification and retrofitting. Following the modelling, the equivalent static horizontal forces as a result of the relevant response spectrum are generated using the FE-software. Based on this procedure and with reference to Eurocode EN 1995 [2] for timber structures, the bracing system has been dimensioned for the maximum normal force resulting from the earthquake with a return period of 225 years corresponding to a peak ground acceleration of 0.35g. The considered earthquake reflects the regional seismicity described herein by a respective response spectrum with regard to the seismic provisions of Eurocode EN 1998 [3]. The reduced return period of 225 years compared to 475 years applied in design is selected in order to reflect a more reluctant safety target for existing structures [4]. The respective seismic hazard analysis is taken from Pradhan [5] and Chaulagain [6] and represents site specific conditions. The improvement of the overall load-bearing behaviour influenced by the bracing, is subsequently checked by verifying the masonry walls using the Eurocode for masonry EN 1996 [7]. The material resistance parameters are taken from local studies and related testing outcomes [8]. The obtained structural analysis results show that wall shear capacity is utilized up to a ratio of 65% and the wall bending capacity is exceeded by 72%. However, when compared with the original building, it can be determined that the mutual floor displacements can be reduced by a factor of up to 4.3 due to the proposed bracing system. Consequently, further retrofitting measures are recommended for the masonry. In that respect lower reliability levels can be of interest since a “discount” in the safety requirements for existing structures, however by fulfilling acceptable human safety levels, is usually unavoidable due to economical constraints. The contribution leads to the conclusion that by retaining the static replacement system in the form of a truss, but adapting the building materials used, the basic functionality of the xamined system can be provided. Although the FEM calculations have demonstrated satisfactory results further experimental campaigns are necessary to define the material properties of the considered typical building structures with respect to the analysed failure modes. The proposed approach supports efficient design of interventions in post-earthquake phases. Y1 - 2021 U6 - https://doi.org/10.11159/iccefa21.110 PB - Avestia Publishing ER - TY - CHAP A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris T1 - Snow Load Monitoring - Measure to Control Reliability of the Roof of a Stadium T2 - International Conference Structural Reliability & Modelling in Mechanics, 24.-25.05.2018, Ostrava, Czech Republic N2 - This contribution shows how monitoring can be used to control reliability of a structure not complying with the requirements of Eurocodes. A general methodology to obtain cost-optimal decisions using limit state design, probabilistic reliability analysis and cost estimates is utilised in a full-scale case study dealing with the roof of a stadium located in Northern Italy. The results demonstrate the potential of monitoring systems and probabilistic reliability analysis to support decisions regarding safety measures such as snow removal, or temporary closure of the stadium. KW - Cost optimisation KW - decision making criteria KW - Eurocodes KW - monitoring KW - reliability analysis KW - snow load KW - stadium roof KW - standard Y1 - 2018 UR - www.researchgate.net/publication/325569518_Snow_Load_Monitoring_-_Measure_to_Control_Reliability_of_the_Roof_of_a_Stadium ER - TY - CHAP A1 - Sýkora, Miroslav A1 - Holicky, Milan A1 - Diamantidis, Dimitris T1 - Target Reliability for Existing Civil Engineering Systems T2 - 2016 Second International Symposium on Stochastic Models in Reliability Engineering, Life Science and Operations Management (SMRLO), 15-18 Feb. 2016, Beer Sheva, Israel N2 - Specification of the target reliability levels is one of the key issues of the assessment of existing systems. ISO 2394:2015 indicate procedures for specification of the target reliability levels by optimisation of the total cost related to an assumed remaining working life of a structural system. These approaches are critically compared with human safety criteria and with recommendations of present standards. It appears that the requirement on the same target reliability levels for existing civil engineering systems as for newly designed is uneconomical. Decisions in the assessment can result in the acceptance of the actual state or in upgrade of the existing structure, two reliability levels are thus needed - the minimum level below which the structure is unreliable and should be upgraded, and the target level indicating an optimum upgrade strategy. When reliability of a system or its key component is verified (as compared to design of a common component), the target reliability index should be increased by about 0.5. KW - cost optimization KW - Economics KW - existing structural systems KW - human safety KW - ISO Standards KW - Optimization KW - Reliability engineering KW - safety KW - target reliability Y1 - 2016 U6 - https://doi.org/10.1109/SMRLO.2016.28 SP - 109 EP - 114 PB - IEEE ER - TY - CHAP A1 - Sýkora, Miroslav A1 - Markova, Jana A1 - Diamantidis, Dimitris T1 - Bayesian Network Application for the Risk Assessment of Existing Energy Production Units T2 - 2016 Second International Symposium on Stochastic Models in Reliability Engineering, Life Science and Operations Management (SMRLO), 15-18 Feb. 2016, Beer Sheva, Israel N2 - A Bayesian network is applied in this contribution in order to assess the risks of a selected production unit in a fossil power station. A general framework for the risk assessment of production units of a power station is presented first by implementing statistical methods and Bayesian networks. Special emphasis is given to the input data consisting of failure rates which are obtained on the basis of recorded data and expert judgements. The consequences of failure are divided into economical and human (societal): economic consequences include outages of key technological devices, societal consequences cover potential injuries and fatalities. Probabilistic risk assessment methods are applied to the selected production unit of a power station. The influence of the uncertainties in the considered technical parameters on the availability of the unit is assessed and the acceptance of the calculated availability represented through the mean value and the standard deviation is discussed. Societal risks given in terms of weighted injuries and fatalities are obtained and respective risk acceptance criteria are presented. Uncertainties affecting the risks are discussed. It appears that the proposed framework provides a valuable assessment of the influence individual devices and their components on availability and societal risk. For that purpose the used methodology, intentionally simplified for operational applications, includes important factors affecting risks of production units. It is concluded that Bayesian networks are a transparent method for the probabilistic risk assessment of complex technological systems. The results of the performed analyses can be easily updated when additional information becomes available as illustrated in characteristic examples. KW - Availability KW - Bayes methods KW - Bayesian networks KW - Economics KW - Power generation KW - Probabilistic logic KW - Production KW - Production unit KW - Risk analysis KW - Societal risk KW - Uncertainties KW - uncertainty Y1 - 2016 U6 - https://doi.org/10.1109/SMRLO.2016.116 SP - 656 EP - 664 PB - IEEE ER - TY - CHAP A1 - Holicky, Milan A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav ED - de Wilde, W. P. ED - Hernández, S. ED - Kravanja, S. T1 - Economically optimum structural design BT - methodology and case study T2 - High Performance and Optimum Design of Structures and Materials III (HPSM/OPTI 2018) ; Ljubljana, Slovenia 11.07.2018 - 13.07.2018 N2 - Codes of practice aim to assure structures have acceptable risks to the public and the minimum total costs over the working life of a design. However, current codified criteria for structural design correspond to a broad range of reliability levels, specified for dissimilar reference periods even though their recalculation for different periods is uncertain due to unknown dependence of failure events in time. In this contribution, target reliability levels are specified on the basis of probabilistic risk optimization considering the objective function as a sum of various costs including effects of time to failure and discounting. A case study presents probabilistic optimization of the roof of a stadium for 4,000 spectators and illustrates the effect of the considered input parameters. Failure consequences and relative cost of safety measure are shown to be major factors affecting the optimum reliability level. Less important factors are the discount rate and working life. Large uncertainty in failure cost estimates seems to have only a marginal effect on derived optimum reliability levels. KW - failure consequences KW - risk acceptance KW - probabilistic optimization KW - target reliability, KW - stadium KW - total cost KW - working life Y1 - 2018 U6 - https://doi.org/10.2495/hpsm180151 SP - 143 EP - 153 PB - WIT ER - TY - CHAP A1 - Croce, Valeria A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav ED - Vayas, Ioannis ED - Mazzolani, Federico M. T1 - Seismic Damage Evaluation and Decisions on Interventions Supported by UAV-Based Surveys T2 - Protection of Historical Constructions: Proceedings of PROHITECH 2021 N2 - The contribution demonstrates the benefits of Unmanned Aerial Vehicles (UAV)-based surveys for building damage evaluation and decisions on interventions after an earthquake. The case study focuses on the historic village of Castelluccio di Norcia (Italy), heavily damaged by the 2016 earthquake. By constructing a 3D model based on UAV flights, the damage levels are estimated for buildings in the village and an optimal set of intervention measures is proposed. For the decision analysis, a pre-posterior Bayesian technique is utilized. The efficiency of the UAV-based survey is highlighted through a cost-benefit analysis and by considering parameters such as the time constraints, the quality of obtained data and the risk of inspecting persons. The proposed method seems to be efficient in organizing rescuing activities, managing emergency measures and specifying interventions, following the occurrence of an accidental situation. KW - Decision analysis KW - Natural hazards KW - Post-seismic areas KW - UAV survey Y1 - 2022 SN - 978-3-030-90787-7 U6 - https://doi.org/10.1007/978-3-030-90788-4_20 VL - 209 SP - 206 EP - 221 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Croce, Valeria A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav ED - Bien, Jan T1 - Planning post earthquake surveys: assessments and reconstruction of small historical centres T2 - 1st IABSE Online Symposium 2020, Synergy of culture and civil engineering - history and challenges: Wrocław, Poland, 7-9 October 2020, Proceedings N2 - The contribution presents a methodological procedure for the management and planning of interventions after earthquake events in small historic centres. Reference is made to the case study of Castelluccio di Norcia, a village in the Apennine Mountains affected by the seismic sequence that hit Central Italy in 2016. The earthquake risk of the area and the damaging events of 2016 are critically reviewed. The implementation of cognitive analysis and the application of advanced survey techniques involving the use of nmanned Aerial Vehicles (UAVs) for the purposes of emergency management and monitoring of damaged areas are analysed. The outcomes, combined with the direct involvement of the local population, represent a complete and integrated approach allowing the definition of a) possible intervention strategies, b) related decision criteria and c) practical recommendations for the reconstruction and regeneration of Castelluccio, and, in general, of small historic centres damaged by catastrophic events. Y1 - 2021 UR - http://toc.proceedings.com/57946webtoc.pdf SN - 978-1-7138-2387-2 SP - 332 EP - 339 PB - Curran Associates Inc CY - Red Hook, NY ER - TY - CHAP A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Reliability Differentiation and Uniform Risk in Standards BT - a Critical Review and a Practical Appraisal: kriticki pregled i prakticna ocjena T2 - Scientific Symposium Future Trends in Civil Engineering, Zagreb,Croatia, 17 October 2029 N2 - Reliability of structures and infrastructures is a major issue in structural engineering. Structural standards have traditionally been mainly concerned with public safety preventing loss of life or injury; this view has been shifting in recent years towards minimisation of economic loss. This contribution discusses the reliability differentiation principle in modern standards. Its aim is to achieve uniform risk levels for the various classes of structures. Codified criteria for reliability differentiation and risk informed decisions inherent in standards and especially in the Eurocodes are critically reviewed. It is shown that the classification of structures based on consequences of failure is an approach that has not been widely implemented in everyday design. Practical rules for the classification and implementation in design are needed and related proposals are presented. T2 - Razlikovanje pouzdanosti i ujednacenost rizika u propisima Y1 - 2020 U6 - https://doi.org/10.5592/CO/FTCE.2019.11 SP - 241 EP - 260 ER - TY - JOUR A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Mueller, Dominik A1 - Sousa, Helder T1 - A practical guide on the quantification of value of information gained by structural health monitoring and application to historic masonry structures JF - Structure and Infrastructure Engineering N2 - Structural health monitoring (SHM) projects are mostly based on semi-empirical decisions, emphasising the importance of the structure and lacking a rational comparison of the benefits and costs. The present work offers guidance to overcome this, based on an objective framework using the quantification of the value of SHM in an engineering context. Firstly, procedures for practising engineers are outlined on the basis of the COST guidelines. Secondly, a case study, focused on the reliability of a historic masonry structure, demonstrates the optimisation of surveys based on non-destructive tests calibrated by destructive tests. Both the outlined procedures and case study are carefully prepared and in tune, so the reader can easily understand the feasibility of the framework. Decisions on the utilisation of SHM in practical applications can be effectively achieved based on the highest expected utility gained by SHM. For this, two scenarios are needed: (i) a scenario with at least one SHM strategy and (ii) a scenario without any SHM. KW - Decision-making KW - guidelines KW - historic masonry KW - optimisation KW - STRENGTH KW - structural health monitoring KW - tests KW - uncertainty KW - value of information Y1 - 2020 U6 - https://doi.org/10.1080/15732479.2020.1857793 VL - 18 IS - 4 SP - 441 EP - 455 PB - Taylor&Francis ER - TY - JOUR A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Holický, Milan A1 - Marková, Jana A1 - Rózsás, Árpád T1 - Assessment of compressive strength of historic masonry using non-destructive and destructive techniques JF - Construction and Building Materials N2 - Masonry structures were built by various techniques using different materials, the properties of which exhibit a considerable scatter dependent on periods of construction and region-specific conditions. For historic structures with a heritage value, various non- or minor-destructive tests (NDTs) are commonly applied, while the application of destructive tests (DTs) is minimized. The contribution is based on investigations of 15 historic stone and clay brick masonry structures, for which NDT strengths of masonry units are verified by DTs. The proposed operational approach makes it possible to account for statistical uncertainty due to a limited number of DTs used to calibrate NDTs. KW - Calibration KW - Clay bricks KW - Compressive strength KW - Mortar KW - Non-destructive test KW - Statistical analysis KW - Stone masonry KW - Uncertainty Y1 - 2018 U6 - https://doi.org/10.1016/j.conbuildmat.2018.10.180 VL - 193 IS - December SP - 196 EP - 210 PB - Elsevier ER - TY - CHAP A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Implementing Snow Load Monitoring to control Reliability of a Stadium Roof T2 - Transactions of VSB N2 - This contribution shows how monitoring can be used to control reliability of a structure not complying with the requirements of Eurocodes. A general methodology to obtain cost-optimal decisions using limit state design, probabilistic reliability analysis and cost estimates is utilised in a full-scale case study dealing with the roof of a stadium located in Northern Italy. The results demonstrate the potential of monitoring systems and probabilistic reliability analysis to support decisions regarding safety measures such as snow removal, or temporary closure of the stadium. KW - Cost optimisation KW - decision making criteria KW - Eurocodes KW - monitoring KW - reliability analysis KW - snow load KW - stadium roof, standard Y1 - 2019 U6 - https://doi.org/10.35181/tces-2019-0006 VL - 19 IS - 1 SP - 35 EP - 40 PB - TECHNICAL UNIVERSITY OF OSTRAVA ER - TY - JOUR A1 - Benekos, Ioannis A1 - Diamantidis, Dimitris T1 - On risk assessment and risk acceptance of dangerous goods transportation through road tunnels in Greece JF - Safety Science N2 - Prescriptive and risk-based methods including qualitative, semi-quantitative and quantitative approaches exist for the risk assessment of road tunnels. This paper provides an overview and a brief discussion of these methods and uses representative traffic and accident data in Greece in a typical tunnel conforming with the minimum infrastructure requirements of the European Directive 2004/54/EC to compare and discuss the resulting risk for each of these methods. Conclusions regarding the implementation of risk analysis methods and the use of the associated existing national guideline are drawn and recommendations for further developments in standards are provided. An integrated framework for the optimal selection of safety measures based on risk reduction and socio-economic considerations is proposed and its applicability in risk analysis of road tunnels is discussed. (C) 2016 Elsevier Ltd. All rights reserved. KW - Accidents KW - Dangerous goods KW - Risk KW - Risk acceptance KW - Risk analysis KW - Risk assessment KW - Road tunnels Y1 - 2017 U6 - https://doi.org/10.1016/j.ssci.2016.07.013 VL - 91 IS - 91 SP - 1 EP - 10 PB - Elsevier ER - TY - JOUR A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Holicky, Milan A1 - Jung, Karel T1 - Target reliability for existing structures considering economic and societal aspects JF - Structure and infrastructure engineering N2 - Specification of target reliability levels is one of the key issues of the assessment of existing structures. ISO 13822:2010 and ISO 2394:2015 indicate procedures for specification of target reliability levels by optimisation of the total cost related to an assumed remaining working life of a structure. These approaches are critically compared with human safety criteria, with target levels based on a marginal life-saving costs principle, and with recommendations of present standards. Optimal target reliability levels are then derived in the representative case study for an existing structural member. It appears that the requirement to reach the same target reliability levels for existing and new structures is uneconomical. Decisions made in the assessment can result in the acceptance of the actual state or in the upgrade of an existing structure. Two reliability levels are thus needed - the minimum level below which the structure is unreliable and should be upgraded, and the target level indicating an optimum upgrade strategy. It is recommended that these levels be established using economic optimisation and the marginal life-saving costs principle, as both the approaches take into account the costs of safety measures and the failure consequences. KW - design KW - Economic optimisation KW - existing structures KW - human safety KW - Life Quality Index KW - Optimization KW - target reliability, *GuI Y1 - 2017 U6 - https://doi.org/10.1080/15732479.2016.1198394 VL - 13 IS - 1 SP - 181 EP - 194 PB - Taylor&Francis ER - TY - JOUR A1 - Retief, Johan Verster A1 - Diamantidis, Dimitris A1 - Barnardo-Viljoen, Celeste A1 - van der Klashorst, Etienne T1 - Extreme actions and climate change: experience gained in South Africa and Germany JF - Civil Engineering and Environmental Systems N2 - The results of a survey of climate change developments in South Africa and Germany from the perspective of its relevance to extreme actions on infrastructure are presented in this paper. It is concluded that the importance of climate change is broad and varied. However incorporation into practice is mostly nominal. Although general trends of climate change are confirmed, proper information on changes in extreme conditions is limited. Coastal engineering seems to be the field which is most active in providing for climate change. It is concluded that risk-based methodologies developed to treat the variability and uncertainties of extreme actions and consequences in present practice provide a sound basis for treating the effects of climate change in a rational and optimal manner. It is also clear that there is strong motivation for extensive research as the best action to be taken presently, anticipating appropriate adjustment of re-optimised design methodologies. KW - climate change KW - extreme actions KW - infrastructure KW - risk-based methodologies KW - optimised design Y1 - 2014 U6 - https://doi.org/10.1080/10286608.2014.912640 SN - 1029-0249 SN - 1028-6608 VL - 31 IS - 2 SP - 179 EP - 188 PB - Taylor & Francis CY - Abingdon ER - TY - CHAP A1 - Retief, Johan Verster A1 - Barnardo-Viljoen, Celeste A1 - van der Klashorst, Etienne A1 - Diamantidis, Dimitris ED - Deodatis, George ED - Ellingwood, Bruce ED - Frangopol, Dan M. T1 - Extreme actions and climate change T2 - Safety, Reliability, Risk and Life-Cycle Performance of Structures and Infrastructures : proceedings of the 11th International Conference on Structural Safety and Reliability, New York, USA, 16-20 June 2013 Y1 - 2014 SN - 9780429227950 SP - 1543 EP - 1550 PB - CRC Press CY - London ER - TY - JOUR A1 - Sýkora, Miroslav A1 - Holický, Milan A1 - Diamantidis, Dimitris T1 - Probabilistic updating in the reliability assessment of industrial heritage structures JF - Heron N2 - Assessment of existing structures should be based on the actual as-built conditions concerning geometry, material properties, loading and environmental conditions. A crucial step of the assessment consists in updating of prior information by newly obtained measurements which may be conducted by Bayesian approach. Updating of probabilistic distributions of basic variables or direct updating of failure probability can be effectively used. Application of theoretical principles is illustrated by a case study of a historic factory built in 1900s. The paper is a tribute to Ton Vrouwenvelder for his essential contributions to developments of theory and promotion of practical applications of probabilistic assessment of existing structures. Y1 - 2016 UR - http://www.heronjournal.nl/59-23/1.pdf SN - 0046-7316 VL - 59 IS - 2/3 PB - Stevin-Laboratorium, TU Delft CY - Delft ER - TY - JOUR A1 - Steenbergen, R.D.J.M. A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Holický, Milan A1 - Vrouwenvelder, A.C.W.M. T1 - Economic and human safety reliability levels for existing structures JF - Structural Concrete. JOurnal of the fib N2 - Specifying the target reliability levels is one of the key issues in the assessment of existing structures. For a majority of existing buildings and infrastructures, the design life has been reached or will be reached in the near future. These structures need to be reassessed in order to verify their safety. Eurocodes provide a general basis primarily intended for the design of new structures, but the basic principles can be used for assessing existing buildings, too. Reliability levels are generally based on both economic optimization and criteria for human safety. In this study, both methods are elaborated for existing structures. It appears that the requirement for the same target reliability for existing and new structures is uneconomical. Further, cost optimization seems to yield rather low reliability levels and human safety criteria often become the critical factor. The study concludes with practical guidelines for establishing reliability indices for existing structures linked to Eurocode principles. Y1 - 2015 U6 - https://doi.org/10.1002/suco.201500022 VL - 16 SP - 323 EP - 332 PB - Wiley ER - TY - BOOK A1 - Tanner, Peter A1 - de Diego, Ana A1 - Lara Sarache, Carlos A1 - Prieto, Miguel A1 - Hingorani, Ramón A1 - Holický, Milan A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Menéndez Ondina, Antonio A1 - Croce, Pietro A1 - Bartelletti, Raffaello A1 - Beconcini, Maria Luisa A1 - Formichi, Paolo A1 - Marsili, Francesca A1 - Muzzi, Martina A1 - Rosso, Elisa A1 - Toprak, Selcuk A1 - Inel, Mehmet A1 - Koc, Cem A1 - Nacaroglu, Engin A1 - Senel, Sevket Murat T1 - Operational methods for the assessment and management of aging infrastructure N2 - The Leonardo da Vinci Project, “Innovation Transfer in Risk Assessment and Management of Aging Infrastructures”, CZ/13/LLP-LdV/TOI/134014, addresses the urgent need to train students, young engineers and professionals in the assessment of existing infrastructures. The future of the construction industry lies in moving from new constructions towards the maintenance, repair and rehabilitation of existing structures, particularly of aging infrastructures. Risk management consisting of risk assessment and risk control of existing structure therefore plays thereby an important role. The assessment of existing infrastructures is an imperative issue of great economic significance in most countries around the world, as more than 50 % of all construction activities concerns existing buildings, bridges and other civil engineering works. At present, the Eurocodes which will be used in all CEN Member countries are primarily focused on the design of new structures. Additional operational rules for existing structures are still missing. The international standard ISO 13822 provides only general principles for the assessment of existing structures which should be further developed for their effective operational use in practice. The overall procedure of risk management of aging infrastructures is therefore an urgent issue of great economic significance in most countries around the world. This is primarily caused due to the fact that many infrastructures are affected by action effects, fatigue and environmental influences, and inevitably deteriorate. Moreover, available resources for the maintenance, repair or possible replacement of infrastructures are always limited. Typical questions and problems which must be solved in this context can be summarized as follows: • What is the current state of a particular infrastructure? • What is an acceptable level of the relevant risk? • Which aspects are critical to sustainable performance? • What is the optimum life-cycle cost? • What is the best long-term funding strategy? The proposed project highlights the above problems and focusses also on vocational training in risk management and assessment of aging infrastructure in the partner countries (CZ, DE, ES, IT and TR). The current project addresses the urgent need for practical implementation of principles of the management and risk assessment of existing infrastructures in all the partner countries. The project is supported by the Czech Chamber of Chartered Engineers (ČKAIT). The project consortium, under the leadership of the Klokner Institute of the Czech Technical University in Prague (KI CTU), consists of five other partners, including research institutions and universities from three EU Member States (DE, ES, IT) as well as one associated country (TR), and also the Secondary Technical School of Civil Engineering in Ceske Budejovice (CZ). All researchers within the partnership are involved in research projects dealing with reliability assessment of existing structures. They participate in the national and international standardization activities within the international organizations CEN (European Committee for Standardisation) and ISO (International Standardization Organisation). The project outcomes consist of vocational training materials based on international research and relevant standard committee’s activities, and on the significant experience gained from case studies, and on selected results obtained from the previous projects of the Leonardo da Vinci programme. In particular, the experience gained by the partners of the present consortium from the completed project on vocational training related to assessment of existing structures is utilized. Available innovations are transferred to undergraduate and graduate students, practising engineers and local government representatives. The developed training materials are of practical use in offering illustrative examples and several case studies. All the project outcomes are based on documents of the international research organization, Joint Committee on Structural Safety JCSS and international research projects, selected outcomes of the previous project of the Leonardo da Vinci programme (developed by five partners of the present consortium in 2013-2015) and also on background documents to the new European and international standards. Particular outcomes of the proposed project include practical handbooks, software tools, web-sites, e-learning, courses and seminars organized in the partners´ home countries. The project outcomes will also be offered to other European countries through code committees work, lectures and the project web-sites. It is foreseen that the outcomes being used by engineers, designers, technicians, and representatives of public authorities involved in planning and management will have an impact on the risk-based management of infrastructures. One of the important project outcomes is the present Handbook 2 “Operational Methods for the Assessment and Management of Aging Infrastructure”, which is focussed on operational techniques for the assessment of aging infrastructures supplemented by illustrative case studies developed according to ISO 13822 and Eurocodes for different structures and materials. From the mentioned project also result Handbook 1, where general procedures of risk-management and assessment of aging infrastructures are presented, and Handbook 3, where operational techniques for the assessment of aging infrastructures supplemented by illustrative case studies are presented with a more basic approach. Handbook 2 consists of eleven chapters. Chapter 1 gives a brief introduction. Chapter 2 summarizes current applicable standards and codes for existing structures. Chapter 3 reviews survey methods. The remaining chapters are devoted to the illustration of relevant case studies, referring to the assessment of different existing infrastructures. In particular, chapter 4 refers to a commercial building, chapter 5 to a r.c. building damaged by corrosion, chapter 6 to silos, chapter 7 to pipelines and water supply systems, chapter 8 to tanks, chapter 9 to historical aqueducts, chapter 10 to bridges and chapter 11 to dams and flood protection systems. In each case studies the entire procedure of the assessment is illustrated step by step emphasizing references to relevant Codes and in particular to ISO 13822. It is believed that the material of this handbook is presented in an understandable way, referring to several case studies. A number of references mentioned in each chapter provide additional background materials, further guidance and information useful to widen the significance and the field of application of the assessment methods illustrated for each case study. Pisa and Prague, 2015 Y1 - 2015 SN - 9788882501471 PB - Tipografía editrice Pisana CY - Pisa, Italia ER - TY - CHAP A1 - Barnardo-Viljoen, Celeste A1 - van der Klashorst, Etienne A1 - Retief, Johan Verster A1 - Diamantidis, Dimitris T1 - Extreme actions and climate change: Experience gained in South Africa and Germany T2 - Robust engineering solutions with environmental loading. The 11th International Conference on Structural Safety and Reliability (ICOSSAR 2013), New York, USA N2 - Since resistance against extreme environmental actions explicitly forms part of the basis of structural design, the implications of climate change emphatically needs to be considered. This paper presents the results of a survey of climate change developments in South Africa and Germany from the perspective of its rele-vance to extreme actions on infrastructure. It is concluded that the importance of climate change is broad and varied. However incorporation into practice is mostly nominal. Although general trends of climate change are confirmed, proper information on changes in extreme conditions is limited. Coastal engineering seems to be the field which is most active in providing for climate change. It is concluded that risk based methodologies developed to treat the variability and uncertainties of extreme actions and consequences in present practice provide a sound basis for treating the effects of climate change in a rational and optimal manner. It is also clear that there is strong motivation for extensive research as the best action to be taken presently, anticipating appropriate adjustment of reoptimized design methodologies. Y1 - 2013 PB - Inderscience Enterprises Ltd ER -