TY - CONF A1 - Gerards-Wünsche, Paul A1 - Ratkovac, Mirjana A1 - Schneider, Ronald A1 - Hille, Falk A1 - Baeßler, Matthias T1 - A framework for assessing the reliability of crack luminescence – an automated fatigue crack detection system T2 - SPIE Conference Smart Structures + Nondestructive Evaluation 2023 N2 - The new crack luminescence method offers the possibility of making fatigue surface cracks in metallic materials more visible during inspections through a special coating system. This coating system consists of two layers, whereby the first layer has fluorescent properties and emits visible light as soon as it is irradiated by UV light. The top layer is black and is designed to prevent the fluorescent layer from emitting if no crack develops in the underlying material. The technique proved particularly useful in a wide variety of fatigue tests of steel components under laboratory conditions. Moreover, it has the potential to be used in various industrial applications. To enable industrial deployment and integration into maintenance strategies, a concept study is developed in this contribution, resulting in a qualification framework that can serve as a foundation for determining the reliability of the crack luminescence system in terms of a probability of detection curve. Within this study, factors causing measurement variability and uncertainty are being determined and their influences assessed. Due to the extension of the system by a moving computer vision system for automated crack detection using artificial intelligence, additional long-term effects associated with structural health monitoring systems need to be incorporated into an extended probability of detection study as part of the technical justification. Finally, important aspects and findings related to design of experiments are discussed, and a framework for reliability assessment of a new optical crack monitoring method is presented, emphasizing the influence of various uncertainty parameters, including long-term effects such as system ageing. T2 - SPIE Conference Smart Structures + Nondestructive Evaluation 2023 CY - Long Beach, CA, USA DA - 24.03.2023 KW - Structural Health Monitoring KW - Non-Destructive Evaluation KW - Probability of Detection KW - Reliability KW - Artificial Intelligence KW - Computer Vision KW - Crack Luminescence KW - Wind PY - 2023 SN - 978-1-5106-6086-1 DO - https://doi.org/10.1117/12.2658390 SP - 1 EP - 15 AN - OPUS4-57244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Rogge, Andreas A1 - Thöns, S. A1 - Bismut, E. A1 - Straub, D. ED - Caspeele, Robby ED - Taerwe, Luc ED - Frangopol, Dan M. T1 - A sampling-based approach to identifying optimal inspection and repair strategies for offshore jacket structures T2 - Proceedings of the sixth international symposium on life-cycle civil engineering (IALCCE 2018) N2 - Identifying optimal inspection and repair strategies for offshore jacket structures is a challenging task. We pre-sent an approach, which is based on recent developments in the field of risk-based operation and maintenance planning at the structural system level. The approach utilizes heuristics to define inspection and repair strate-gies at the system level and to reduce the search space of possible strategies. For each defined strategy, the expected service life cost of inspection, repair and failure is evaluated based on simulated inspection and re-pair histories. Subset simulation is applied to compute the conditional repair and failure probabilities required for this analysis. It also forms the basis for simulating inspection and repair histories. The strategy that mini-mizes the expected service life cost is the optimal one in the set of pre-selected strategies. The underlying condition and performance model accounts for the stochastic dependence among the deterioration states of the different structural elements and the structural redundancy. The approach is demonstrated in a case study considering a jacket-type frame. In this study, we essentially vary the inspection interval, the minimum num-ber of inspected components and the target reliability, and identify the combination that minimizes the ex-pected total service life cost. T2 - The sixth international symposium on life-cycle civil engineering (IALCCE 2018) CY - Ghent, Belgien DA - 28.10.2018 KW - Offshore steel structures KW - Fatigue KW - Reliability KW - Risk KW - Inspection planning PY - 2019 SN - 978-1-138-62633-1 SN - 978-1-315-22891-4 SP - 1081 EP - 1088 PB - Taylor & Francis Group CY - London AN - OPUS4-46434 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Thöns, S. A1 - Fischer, J. A1 - Bügler, M. A1 - Borrmann, A. A1 - Straub, D. T1 - A software prototype for assessing the reliability of a concrete bridge superstructure subjected to chloride-induced reinforcement corrosion T2 - Life-cycle of structural systems - IALCCE 2014 - 4th International symposium on life-cycle civil engineering (Proceedings) N2 - A software prototype is developed for assessing and updating the reliability of single-cell prestressed concrete box girders subjected to chloride-induced reinforcement corrosion. The underlying system model consists of two integrated sub-models: a condition model for predicting the deterioration state of the box girder and a structural model for evaluating the overall system reliability. The condition model is based on a dynamic Bayesian network (DBN) model which considers the spatial variation of the corrosion process. Inspection data are included in the calculation of the system reliability through Bayesian updating on the basis of the DBN model. To demonstrate the effect of partial inspections, the software prototype is applied to a case study of a typical highway bridge with six spans. The case study illustrates that it is possible to infer the condition of uninspected parts of the structure due to the spatial correlation of the corrosion process. T2 - IALCCE 2014 - 4th International symposium on life-cycle civil engineering CY - Tokyo, Japan DA - 16.11.2014 PY - 2015 SN - 978-1-138-00120-6 SP - 846 EP - 853 PB - Taylor & Francis CY - London AN - OPUS4-32220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Thöns, Sebastian A1 - Straub, D. ED - Strauss, A. ED - Frangopol, D.M. ED - Bergmeister, K. T1 - Probalistic fatigue crack growth modeling for reliability-based inspection planning T2 - Life-cycle and sustainability of civil infrastructure systems N2 - The fatigue deterioration modeling for welded steel structures subjected to high cycle fatigue is presented in the current document. The aim of this paper is to formulate approaches based on actual Research results for the phases fatigue crack initiation, fatigue propagation and fatigue failure. The physical characteristics of the approaches are discussed in combination with the associated uncertainties and the probabilistic modeling of this time variant reliability problem. The fatigue deterioration modeling documented here serve as a basis for a reliability-based approach to inspection planning. T2 - 3rd International symposium on life-cycle civil engineering CY - Vienna, Austria DA - 03.10.2012 PY - 2012 SN - 978-0-415-62126-7 SP - 319 EP - 326 PB - CRC Press AN - OPUS4-27067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Thöns, Sebastian A1 - Straub, D. ED - Strauss, A. ED - Frangopol, D.M. ED - Bergmeister, K. T1 - Reliability-based inspection planning with application to orthotropic bridge deck structures subjected to fatigue T2 - Life-cycle and sustainability of civil infrastructure systems N2 - A reliability-based approach to inspection planning for welded steel structures subjected to high cycle fatigue is presented in the current document. Inspections are an effective means to control the Progress of fatigue deterioration and the presented approach allows to determine the minimum required inspection effort so that the considered structure complies with the given risk acceptance criteria in terms of target reliability throughout its service life. T2 - 3rd International symposium on life-cycle civil engineering CY - Vienna, Austria DA - 03.10.2012 PY - 2012 SN - 978-0-415-62126-7 SP - 311 EP - 318 PB - CRC Press AN - OPUS4-27068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Schneider, Ronald A1 - Baeßler, Matthias ED - Yokota, H. ED - Frangopol, D. M. T1 - Bayesian system identification of a reinforced concrete beam subject to temperature variations based on static response data T2 - Bridge Maintenance, Safety, Management, Life-Cycle Sustainability and Innovations N2 - Changes in the measured response of structural systems can be an indication of structural damages. However, such changes can also be caused by the effect of varying environmental conditions. To detect, localize and quantify changes or damages in structural systems subject to varying environmental conditions, physics-based models of the structural systems have to be applied which explicitly account for the influence of ambient conditions on the structural behavior. Data obtained from the structural systems should be used to calibrate the models and update predictions. Bayesian system identification is an effective framework for this task. In this paper, we apply this framework to learn the parameters of two competing structural models of a reinforced concrete beam subject to varying temperatures based on static response data. The models describe the behavior of the beam in the uncracked and cracked condition. The data is collected in a series of load tests in a climate chamber. Bayesian model class selection is then applied to infer the most plausible condition of the beam conditional on the available data. T2 - Tenth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2020) CY - Online meeting DA - 11.04.2021 KW - Structural systems KW - Bayesian system identification KW - Damage identification KW - Environmental effects KW - Structural health monitoring PY - 2021 DO - https://doi.org/10.1201/9780429279119-125 SP - 934 EP - 941 PB - CRC Press AN - OPUS4-52809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thöns, S. A1 - Schneider, Ronald A1 - Faber, M.H. ED - Haukaas, T. T1 - Quantification of the value of structural health monitoring information for fatigue deteriorating structural systems T2 - ICASP 12 - 12th International conference on applications of statistics and probability in civil engineering (Proceedings) N2 - This paper addresses the quantification of the value of structural health monitoring (SHM) before its implementation for structural systems on the basis of its Value of Information (VoI). The value of SHM is calculated utilizing the Bayesian pre-posterior decision analysis modelling the structural life cycle performance, the integrity management and the structural risks. The relevance and precision of SHM information for the reduction of the structural system risks and the expected cost of the structural integrity management throughout the life cycle constitutes the value of SHM and is quantified with this framework. The approach is focused on fatigue deteriorating structural steel systems for which a continuous resistance deterioration formulation is introduced. In a case study, the value of SHM for load monitoring is calculated for a Daniels system subjected to fatigue deterioration. The influence of and the value of SHM in regard to the structural system risks and the integrity management is explicated and explained. The results are pointing to the importance of the consideration of the structural system risks for the quantification of the value of SHM. T2 - ICASP 12 - 12th International conference on applications of statistics and probability in civil engineering CY - Vancouver, Canada DA - 12.07.2015 PY - 2015 DO - https://doi.org/10.14288/1.0076284 SP - Paper 605, 1 EP - 8 AN - OPUS4-34332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zorn, Sebastian A1 - Unger, Jörg F. A1 - Schneider, Ronald ED - Silva Gomes, J. F. ED - Meguid, S. A. T1 - A probabilistic method for identification of vehicle loads and system parameters for reinforced concrete bridges T2 - New trends on integrity reliability failure N2 - Growth of vehicle traffic density can be observed in many countries all over the world. This accretion is caused by world-wide population growth on the one hand, but also by increasing freight volumes and, thus, freight transports on the streets on the other hand. This increased exposure becomes more and more of a problem for the civil infrastructure such as bridges. Many of these bridges are nowadays stressed to their limits by higher loads than they were originally designed for and/or operating times beyond the initially predicted life span. This raises questions about structural safety and lifetime prediction, of course, and therefore illustrates the need for accurate structural monitoring. Since the lifetime of bridge structures is primarily influenced by their traffic loading, an accurate identification of load configurations over the whole length of a structure is most desirable. In this paper, a method for vehicle load identification is proposed. It involves Bayesian Analysis and (quasi-)static importance functions in order to estimate vehicle positions, velocities and weights. The structure is modeled with finite elements in order to generate model predictions for different load configurations. The model predictions are compared to the actual measured data to identify the most probable loading configuration for that measurement. This involves the use of enhanced Monte Carlo simulations such as MCMC to reduce the computational effort. The measured data from different kinds of sensors can (and should) be combined for accuracy gain – in this case a combination of measured displacements and inclinations. Since the measurements take place over some time during the passage of the vehicle, these estimations are carried out for several time instants for which the estimation is carried out. The advantage of using Bayesian Updating Method is the embodied learning effect leading to an improvement of the estimation when adding new information in a new calculation step. Using the estimates for the loading conditions of a bridge structure as well as measurements of the structural responses, Bayesian analysis is again used in order to estimate localized structural parameters such as Young's modulus or Moments of Inertia in form of probability density functions yielding most probable values for the parameters. Considering the difficulties for load identification close to the support poles of the bridge and therefore for the proposed structural parameter identification procedure, it is clear that this problem is ill posed. Bayesian regularization methods also have proven to be very effective when handling ill posed problems. T2 - IRF2016 - Integrity Reliability Failure CY - Porto, Portugal DA - 24.07.2016 KW - Vehicle load identification KW - Structural health monitoring KW - Bayesian updating method PY - 2016 SN - 978-989-98832-4-6 VL - 2016 SP - PAPER REF: 6294-575 EP - 576 PB - INEGI-Instituto de Ciencia e Inovacao em Engenharia Mecanica e Gestao Industrial CY - Porto - Portugal AN - OPUS4-39833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -