| 1. |
- Björnsson, Ivar, et al.
(författare)
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Simulation of collision loads to bridge supporting structures from heavy goods vehicle traffic on Swedish highways
- 2013
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Ingår i: Safety, Reliability, Risk and Life-Cycle Performace of Structures & Infrastructures. - 9781138000865 ; , s. 2113-2120
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Konferensbidrag (refereegranskat)abstract
- This paper investigates accidental loading in the form of heavy goods vehicle (HGV) collisions to bridge supporting structures. Structures adjacent to roads are normally strong enough to resist collisions from light vehicles, while it may not be feasible for such structures to resist collisions from all HGVs (greater than 3,5 tons). In this paper a probabilistic model is used to determine these collision forces while Bridge Weigh In Motion (B-WIM) measurements performed on Swedish highways form the foundation for the calculated results. The probabilistic model is evaluated using Monte-Carlo simulations in which approximately 60 thousand B-WIM measurements are included. The results are compared with values given in the design codes and the implications of using codified prescriptive approaches in Eurocode 1-7 (CEN 2006) are discussed. It is found that the tabulated values given in the code are significantly lower than the values determined from the simulations. It can be questioned whether these loads are intended to provide adequate safety with respect to the intensity and weights of HGV vehicles in today’s traffic environment.
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| 2. |
- Blomfors, Martin, et al.
(författare)
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Reliability analysis of corroded reinforced concrete beam with regards to anchorage failure
- 2019
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Ingår i: Life-Cycle Analysis and Assessment in Civil Engineering. - : CRC Press/Balkema. - 9781138626331 - 9781351857574 ; , s. 337-344, s. 337-344
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Konferensbidrag (refereegranskat)abstract
- Reinforcement corrosion is a common problem in reinforced concrete infrastructure today, and it is expected to increase in the future. To simply replace the corroded structures with new ones requires large resources, both in financial and environmental terms. Therefore it is important that existing structures are used to their full potential, also after the onset of corrosion. This paper presents a reliability study of the anchorage capacity of a reinforced concrete beam including reinforcement corrosion. The sensitivity of the different input parameters is also studied. As expected, the results show that the reliability is reduced with corrosion; the magnitude depends to a large extent on the modelling uncertainty used for the bond model for corroded reinforcement. The sensitivity analysis shows an influence of corrosion also on the sensitivities of the input parameters, which is expected based on the properties of the underlying bond model. This paper demonstrates that probabilistic evaluations give valuable insight of the reliability, which can be used to prolong the service-life of existing infrastructure and save both money and the environment.
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| 3. |
- Larsson Ivanov, Oskar, et al.
(författare)
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Prolca—treatment of uncertainty in infrastructure LCA
- 2019
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Ingår i: Life-Cycle Analysis and Assessment in Civil Engineering. - : CRC Press/Balkema. - 9781138626331 - 9781351857574 ; , s. 2923-2930
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Konferensbidrag (refereegranskat)abstract
- The construction, operation and maintenance of transportation infrastructure require energy and materials which impact the environment. Large infrastructure projects thus use resources intensively and leave a significant environmental footprint. To demonstrate and support the sustainability of such large-scale projects, life cycle assessment (LCA) has become a common tool to evaluate environmental impacts in all stages of infrastructure life cycle, from raw material production through end-of-life management. However, the various phases of the assessment are all associated with uncertainties. If decisions are made without consideration of these uncertainties, they might be misleading and suboptimal. In this paper, results are presentedwhere variations associated with different parameters and tools for life cycle assessment have been considered using probabilistic methods. A categorization of common uncertainties in LCA is also included. The most influential parameters can be identified with sensitivity analysis methods, since for LCA with a large number of parameters it may be unreasonable to incorporate all in a probabilistic simulation. For a limited amount of influential variables, Monte Carlo simulation has been used to assess the effects of uncertainties on the results.A bridge has been used as a case study to find important aspects in infrastructure LCA. The results indicate that if the most influential parameters are considered as random variables, it is possible to estimate the uncertainty and increase the validity of the life cycle assessment.
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| 4. |
- Sarmiento Nova, Silvia Juliana, et al.
(författare)
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A risk-based robustness evaluation of a prestressed concrete bridge
- 2023
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Ingår i: Bridge Safety, Maintenance, Management, Life-Cycle, Resilience and Sustainability - Proceedings of the 11th International Conference on Bridge Maintenance, Safety and Management, IABMAS 2022. - London : CRC Press. - 9781032345314 ; , s. 2045-2052, s. 2045-2052
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Konferensbidrag (refereegranskat)abstract
- Existing bridges were designed to satisfy old specifications, and most of them were based on a member-oriented approach. A bridge superstructure is constituted by a group of elements that together form a system, and depending on how robust the system is, a member-oriented approach losses accuracy. Therefore, in this study a preliminary framework of how to assess concrete bridges' robustness is presented. The framework integrates a metamodel-based reliability analysis, and the risk concepts to evaluate the robustness level for concrete bridges considering failure probabilities and consequences. A case study of a prestressed multi-beam concrete bridge is used to validate and illustrate the methodology. The capacity of the individual elements, as well as of the intact and damaged structural system are calculated using finite element modeling (FEM). It was concluded that the framework proposed can be used to assess structural robustness with low computational cost, for the cases in which FEM is implemented.
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| 5. |
- Sarmiento, S., et al.
(författare)
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Redundancy, importance, and robustness analyses for damage scenarios of bridges
- 2023
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Ingår i: Life-Cycle of Structures and Infrastructure Systems - Proceedings of the 8th International Symposium on Life-Cycle Civil Engineering, IALCCE 2023. - 9781003323020 ; , s. 3904-3912
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Konferensbidrag (refereegranskat)abstract
- Bridges are an important part of the traffic infrastructure, which are subjected to high safety requirements and economic consequences in case of functionality failure. Therefore, it is needed to consider potentially substantial direct and indirect risks during service life, i.e., the need for risk and robustness analyses. Over the last decades, various quantitative performance criteria have been developed but their interrelation and compatibility has hardly been systematically studied. This paper contains a proposal of a novel and complementary formulation of interrelations between reliability- and risk-based robustness, importance, and redundancy indicators. The classification, derivation, and exemplification of the interrelations between these indicators are presented and formulated for two case studies of a pre-stressed concrete bridge considering different hazard scenarios namely overloading and chloride attack. The analyses and applications lead to the identification of interrelations between the reliability based robustness, redundancy and importance indicator indicators and with the risk based robustness indicator.
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