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  • 1.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Carlsson, Fredrik
    Lunds Tekniska Höskola.
    Enckell, Merit
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Enochsson, Ola
    Luleå Tekniska Universitet.
    Karoumi (Redaktör), Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Malm, Richard
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Betongbyggnad.
    Plos, Mario
    Chalmers Tekniska Högskola.
    Sundquist, Håkan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE).
    Täljsten, Björn
    LuleåTekniska Universitet.
    Wiberg, Johan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Ülker, Mahir
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Modern mät- och övervakningsmetodik för bedömning av befintliga broar2007Rapport (Annet vitenskapelig)
  • 2.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Attenuating resonant behavior of a tied arch railway bridge using increased hanger damping2012Inngår i: Bridge Maintenance, Safety, Management, Resilience and Sustainability - Proceedings of the Sixth International Conference on Bridge Maintenance, Safety and Management, Taylor & Francis Group, 2012, s. 2572-2577Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, dynamic analyses and field measurements of a tied arch railway bridge is presented. Excessive vibrations of the hangers were obtained, caused by resonance during train passages. The resulting increase of the stress level and number of stress cycles were shown to decrease the fatigue service life significantly. The most critical section is a threaded turnbuckle connection of the hangers. Due to low damping of the hangers, more than 50 % of the cumulative fatigue damage was related to free vibrations after train passage. Passive dampers were installed to attenuate the vibrations by means of increased damping. A combination of field measurements and numerical models are used to investigate the behavior of the bridge and the impact of increased hanger damping.

  • 3.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Dynamics of railway bridges, analysis and verification by field tests2015Inngår i: EVACES'15, 6th International Conference On Experimental Vibration Analysis For Civil Engineering Structures / [ed] Glauco Feltrin, EDP Sciences, 2015, Vol. 24Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The following paper discusses different aspects of railway bridge dynamics, comprising analysis, modelling procedures and experimental testing. The importance of realistic models is discussed, especially regarding boundary conditions, load distribution and soil-structure interaction. Two theoretical case studies are presented, involving both deterministic and probabilistic assessment of a large number of railway bridges using simplified and computationally efficient models. A total of four experimental case studies are also introduced, illustrating different aspects and phenomena in bridge dynamics. The excitation consists of both ambient vibrations, train induced vibrations, free vibrations after train passages and controlled forced excitation.

  • 4.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Connor, Alan
    Trinity College Dublin.
    Development of a multi-passive tuned mass damper, theory and experiments2014Inngår i: Proceedings of the 9th International Conference on Structural Dynamics, EURODYN 2014, Porto, 2014, s. 1551-1556Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, a bi-directional multi-passive tuned mass damper is presented. The applicationfor the damper is on vertical hangers of an existing steel arch railway bridge.The hangers have been found susceptible to resonance and the resulting stressesresults in a reduced service life due to fatigue. Due to different boundaryconditions, the natural frequencies of the hangers are different in thelongitudinal and the transverse direction. In addition, the natural frequenciesincrease during train passage, due to increased tensile force in the hangers. Aprototype of the damper has been developed, consisting of two suspended massescoupled in series. Different lateral suspensions are used to obtain differentnatural frequencies in the longitudinal and the transverse direction. One massis tuned to the conditions of the fully loaded bridge and the other mass to theunloaded bridge. The performance of the damper is verified using controlledloading under laboratory conditions and the results are compared with a finiteelement model. The damper is shown to perform as expected and the motion of thetwo masses is near uncoupled. Finally, the performance of the damper isverified by in-situ testing on the case study bridge.

  • 5.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Connor, Alan
    External damping of stay cables using adaptive and semi-active vibration control2013Inngår i: Proceedings of the 8th International Cable Supported Bridge Operators Conference, Edinburgh, Scotland, 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, the performances of different external damping systems for stay cables are studied based on numerical simulations. Two types of dampers have been analysed; a near anchorage viscous damper and a tuned mass damper (TMD) mounted near the midspan of the stay cable. For the passive case, both dampers are tuned to the fundamental mode of vibration of the cable. The optimal viscous damping for the near anchorage damper is determined based on well-known equations for a taut string. For the TMD, parametrical studies have been performed to determine the optimal damping ratio as function of the damper mass. The resulting vibration mitigation from the two systems are also studied for higher modes of vibration and the potential increase in performance using an adaptive or semi-active vibration control system is studied.

  • 6.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Connor, Alan
    Semi-active damping systems for railway bridges2012Inngår i: / [ed] Colin Caprani, Alan O'Connor, Dublin, 2012, s. 177-182Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, a semi-active control system for vibration mitigation of railway bridges is presented. The real time frequency response is estimated using a short-time Fourier transform, employing curve fitting to relevant peaks for increased accuracy. A control algorithm developed in Matlab® is linked to a commercial FE-software, facilitating application on arbitrary structures. A numerical study of an existing tied arch railway bridge is presented. From earlier field measurements and numerical analysis, resonance of several hangers during train passage was observed. This was shown to significantly reduce the fatigue service life of the hangers and for the most critical section about 50% of the cumulative damage was related to free vibrations. A system of passive dampers was later installed and the increase in resulting damping was measured. Within the present study, the previous results are reanalysed and compared with a semi-active approach. The natural frequencies of the hangers vary as a result of the variation in axial force. A semi-active control system has the potential to improve the vibration response of the structure when compared to the installed passive system.

  • 7.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Connor, Alan
    Vibration mitigation of railway bridges using adaptive damping control2013Inngår i: Assessment, Upgrading and Refurbishment of Infrastructures, 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, the advantage of an adaptive damping system is presented. A damper with variable stiffness is tuned based on estimates of the real-time frequency response, facilitating optimal vibration mitigation. The performance of the developed routines is investigated on an existing tied arch railway bridge. Based on previous field measurements, resonant behaviour of several hangers was found. In combination with low structural damping, the induced stresses resulted in a reduced fatigue service life. Passive dampers are currently installed on the longer hangers, each tuned to the fundamental natural frequency of the individual hanger. However, increased axial force during train passage results in a significant variation in natural frequency, with an apparent risk of detuning the passive dampers. The predicted performance of an adaptive damping system to account for this variation in dynamic behaviour is presented and its potential application is discussed.

  • 8.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Leander, John
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Extending the fatigue service life of a railway bridge by local approaches2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, fatigue assessment of a steel railway bridge is presented. The bridge is located in central Stockholm, Sweden, and is one of the most vital links for the railway network. The bridge services both freight trains and commuter trains with more than 500 passages per day. The main load bearing structure is designed as a steel grillage of welded I-beams. Fatigue critical sections have been identified at locations where secondary bracing systems are welded to the flanges of the I-beams. Both numerical simulations and extensive field measurements have shown a significant exceedance of the theoretical fatigue service life. Based on analysis of local stress concentrations, improvement of fatigue critical details have been suggested. The decrease in stress concentration is demonstrated both by numerical simulations and in-situ field measurements and shows a significant improvement when estimating the remaining fatigue service life.

  • 9.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Connor, Alan
    Trinity College Dublin.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Development and testing of a bi-directional multi-passive tuned mass damperInngår i: Computer-Aided Civil and Infrastructure Engineering, ISSN 1093-9687, E-ISSN 1467-8667Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    This paper presentsthe development and testing of a bi-directional multi-passive tuned mass damper(bi-MTMD). A prototype of the damper has been built and tested under laboratoryconditions. The damper was developed for application to a vertical hanger on anexisting tied-arch railway bridge. During train passage, resonance has beenobserved in several hangers, resulting in a reduction in the predicted fatigueservice life. The objective of the damper is to mitigate the vibrations toreduce the resulting stresses and consequently to extend the life of thehanger. The hanger has different natural frequencies for longitudinal andtransversal bending. In addition, a significant difference in natural frequencyis obtained for the loaded and unloaded bridge, due to the increase in axialforce in the hangers. The developed damper accounts for both scenarios and istuned based on previous field measurements. The results from the laboratoryexperiments are compared with a 3D FE-model of the damper.

  • 10.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Connor, Alan
    Trinity College Dublin.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Development of a Bi-directional Multi-Passive Tuned Mass DamperInngår i: Journal of Structural Engineering, ISSN 0733-9445, E-ISSN 1943-541XArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents the development and testing of a bi-directional multi-passivetuned mass damper (bi-MTMD). A prototype of the damper has been built andtested under laboratory conditions. The damper was developed for application toa vertical hanger on an existing tied-arch railway bridge. During trainpassage, resonance has been observed in several hangers, resulting in areduction in the predicted fatigue service life. The objective of the damper isto mitigate the vibrations to reduce the resulting stresses and consequently toextend the life of the hanger. The hanger has different natural frequencies forlongitudinal and transversal bending. In addition, a significant difference innatural frequency is obtained for the loaded and unloaded bridge, due to theincrease in axial force in the hangers. The developed damper accounts for bothscenarios and is tuned based on previous field measurements. The results fromthe laboratory experiments are compared with a 3D FE-model of the damper.

  • 11.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Swedish Transport Adm Trafikverket, Solna, Sweden.
    O'Connor, Alan
    Trinity College Dublin.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Passive and Adaptive Damping Systems for Vibration Mitigation and Increased Fatigue Service Life of a Tied Arch Railway Bridge2015Inngår i: Journal of Bridge Engineering, ISSN 1084-0702, E-ISSN 1943-5592, Vol. 30, nr 9, s. 748-757Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    n this article, the use of external damping systems for vibration mitigation of railway bridge dynamics is studied. For a presented case study bridge, the performance of different tuned mass damper systems (TMDs) is studied. During train passage, the change in dynamic characteristics of the bridge may produce a significant detune to a passive TMD. Therefore, routines for a variable stiffness TMD using incremental frequency estimates are developed. Based on numerical simulations, the cumulative fatigue damage is calculated for different damper systems. Due to resonant behavior, the results are found to highly depend on the train speed. Based on an assumed probability density function for the train speed, fragility curves are produced to express the probability of fatigue failure as a function of the number of train passages.

  • 12.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Sundquist, Håkan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Evaluating cable forces in cable supported bridges using ambient vibration method2006Inngår i: The International Conference on Bridge Engineering – Challenges in the 21st Century , November 1-3, 2006, Hong Kong, Hong Kong, 2006Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper deals with the assessment of cable forces in existing cable supported bridges using the ambient vibration method. A case study of the Älvsborg suspension bridge in Sweden is presented. Dynamic measurements of the backstays and hangers as well as on each strand in one of the splay chambers have been carried out. The measured frequencies are evaluated and calculations of corresponding axial force in the cable structures are performed taking into account the cable sag, boundary conditions and flexural rigidity. Modal analyses have been used to study the shape of vibration and for comparison with finite element models.

  • 13.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Sundquist, Håkan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Full Scale Tests and Structural Evaluation of Soil-Steel Flexible Culverts for High-Speed Railways2012Inngår i: Second European conference on Buried Flexible Steel structures Rydzyna April 23rd – 24th 2012, 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, results from full-scale tests on a corrugated soil-steel flexible culvert for railway traffic are presented. The bridge was instrumented with strain gauges, accelerometers and displacement gauges, measuring the response from passing trains. The aim of the measurement campaign was to gain knowledge of the dynamic behaviour due to train induced vibrations, both of the bridge structure and the overlying railway embankment. From the measured data, the load distribution and soil-stiffness can be estimated. The results also serve as input for calibration of numerical models that are used for predicting the behaviour due to high-speed trains.

  • 14.
    Andersson, Andreas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. The Swedish Transport Administration (Trafikverket), Sweden.
    Ülker-Kaustell, Mahir
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Tyréns AB, Sweden.
    Borg, Richard
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Dymén, Olivier
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Carolin, Anders
    Trafikverket.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Pilot testing of a hydraulic bridge exciter2015Inngår i: EVACES'15, 6th International Conference on Experimental Vibration Analysis For Civil Engineering Structures / [ed] Glauco Feltrin, Zurich: EDP Sciences, 2015, Vol. 24, s. 02001-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper describes the development of a hydraulic bridge exciter and its first pilot testing on a full scale railway bridge in service. The exciter is based on a hydraulic load cylinder with a capacity of 50 kN and is intended for controlled dynamic loading up to at least 50 Hz. The load is applied from underneath the bridge, enabling testing while the railway line is in service. The system is shown to produce constant load amplitude even at resonance. The exciter is used to experimentally determine frequency response functions at all sensor locations, which serve as valuable input for model updating and verification. An FE-model of the case study bridge has been developed that is in good agreement with the experimental results.

  • 15. Arvidsson, T.
    et al.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Modelling alternatives in the dynamic interaction of freight trains and bridges2014Inngår i: Civil-Comp Proceedings, ISSN 1759-3433, Vol. 104Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper focuses on studying the dynamic response of bridges under passing freight trains. To increase transport efficiency, infrastructure mangers are asked to allow for higher freight train speeds and higher axle loads. However, little work has been done on the influence of increased freight train speeds on bridges. In this paper a two-level factorial experiment was used to identify the most important factors in train-bridge interaction systems comprising the Swedish Steel Arrow freight train passing over simply supported beam bridges. Thereby, the effect of a simple 2D multibody model as opposed to moving forces was set in relation to variations in other key system parameters. Preceding the factorial experiment, four train models were compared to determine a relevant vehicle idealisation. Through the factorial design, effects of single parameters, as well as joint effects from simultaneous changes in several parameters, were evaluated. The type of load model was found to have a large effect, reducing the bridge deck response at resonance considerably for the four studied bridges of span 6, 12, 24 and 36 m. For the relatively light 24 and 36 m span bridges, clear resonance peaks from heavy freight train passages in the speed interval 50-150 km/h were much reduced.

  • 16.
    Arvidsson, Therese
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Andersson, Andreas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Train running safety on non-ballasted bridgesManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    The train running safety on non-ballasted bridges is studied based on safety indices from the vertical wheel–rail forces. A 2D train–track–bridge interaction model that allows for wheel–rail contact loss is adopted for a comprehensive parametric study on high-speed passenger trains. The relation between bridge response and vehicle response is studied for more than 200 theoretical bridges in 1–3 spans. The bridge's inuence on running safety and passenger comfort is differentiated from the influence of the track irregularities. The Eurocode bridge deck acceleration limit for non-ballasted bridges is 5 m/s2 based on the assumed derailment risk at 1g from wheel–rail contact loss. This study shows that the running safety indices are not compromised for bridge accelerations up to 30 m/s2. Thus, accelerations at 1g do not in itself lead to contact loss and there is potential to enhance the Eurocode safety limits for non-ballasted bridges.

  • 17.
    Arvidsson, Therese
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Modelling Alternatives in the Dynamic Interaction of Freight Trains and Bridges2014Inngår i: Proceedings of the Second International Conference on Railway Technology: Research, Development and Maintenance, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper focuses on studying the dynamic response of bridges under passing freight trains. To increase transport efficiency, infrastructure mangers are asked to allow for higher freight train speeds and higher axle loads. However, little work has been done on the influence of increased freight train speeds on bridges. In this paper a two-level factorial experiment was used to identify the most important factors in train-bridge interaction systems comprising the Swedish Steel Arrow freight train passing over simply supported beam bridges. Thereby, the effect of a simple 2D multibody model as opposed to moving forces was set in relation to variations in other key system parameters. Preceding the factorial experiment, four train models were compared to determine a relevant vehicle idealisation. Through the factorial design, effects of single parameters, as well as joint effects from simultaneous changes in several parameters, were evaluated. The type of load model was found to have a large effect, reducing the bridge deck response at resonance considerably for the four studied bridges of span 6, 12, 24 and 36 m. For the relatively light 24 and 36 m span bridges, clear resonance peaks from heavy freight train passages in the speed interval 50-150 km/h were much reduced.

  • 18.
    Arvidsson, Therese
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Train–bridge interaction: a review and discussion of key model parameters2014Inngår i: International Journal of Rail Transportation, ISSN 2324-8386, Vol. 2, nr 3, s. 147-186Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Research in the field of train–bridge interaction is reviewed, with a particular focus on the vertical dynamic response of the bridge. The most influential system parameters are identified and discussed, providing a basis from which to establish an appropriate degree of complexity in train and track modelling. A two-level factorial experiment is presented. This is used to highlight the relative influence of train–bridge interaction in the train–bridge model, compared with variations in other key parameters. We distinguish those parameter combinations in the train–bridge system that lead to a significant reduction in bridge response due to the train–bridge interaction. The present survey fills an important gap in our existing knowledge by synthesising conclusions from the vast literature on train–bridge interaction. Moreover, the knowledge is related to the European design code’s guidelines for dynamic bridge analysis. The conclusions are summarised to give a rough guidance on modelling choices for train–bridge interaction systems.

  • 19.
    Arvidsson, Therese
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Pacoste, Costin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. ELU Konsult AB, Sweden.
    Statistical screening of modelling alternatives in train-bridge interaction systems2014Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 59, s. 693-701Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of parameter variations in railway bridges subjected to train loads has been evaluated within the framework of a two-level factorial experiment. Especially, the influence of train-bridge interaction in comparison to other parameter variations is highlighted. Variations in the system parameters were introduced, corresponding to modelling alternatives considering reasonable uncertainties in a bridge design model. The dynamic effect from a passenger train set has been evaluated at, and away from, resonance in beam bridges of span lengths 6, 12, 24 and 36. m. By means of the two-level factorial design, effects from changes in a single parameter, as well as joint effects from simultaneous changes in several parameters, may be evaluated. The effect of including train-bridge interaction through a simple vehicle model as opposed to moving forces was found most distinct at resonance. The effect of the choice of load model was furthermore shown largest for the bridges of span length 24 and 36. m, where it was found more influential or comparable to the effect of other system parameter uncertainties. The high influence of the load model may well be attributed to the fact that the natural frequencies of the 24 and 36. m bridges are close to the vertical frequency of the primary suspension system of the train. The reduction of response obtained with the train-bridge interaction model are discussed in relation to bridge frequency rather than span length, and compared to the Additional Damping Method given in the European design code.

  • 20.
    Bayoglu Flener, Esra
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Dynamic testing of a soil-steel composite railway bridge2009Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 31, nr 12, s. 2803-2811Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Actual dynamic response of a long-span corrugated steel culvert railway bridge is studied. The bridge, which is a type of soil-steel composite structures, has a span of 11 m. Tests were carried out by measuring strains and displacements during passages of a locomotive at different speeds. Vertical ballast accelerations as well as the effects of braking forces were also measured. The tests showed that the speed has a large influence on the displacements, thrusts and moments. The measured dynamic displacements and thrusts are as much as 20% larger than the corresponding static response. This is greater than the values specified in bridge design codes. Dynamic amplification factors as high as 1.45 were obtained for the moments at the quarter point which is found to be much larger than the values for the crown point. This type of bridge structure is believed to be less sensitive to resonance from passing trains than other common bridge types, due to the high damping values obtained from the forced vibration tests.

  • 21.
    Bayoglu Flener, Esra
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Testing a soil-steel bridge under static and dynamic loads2010Inngår i: Proceedings of the Institution of Civil Engineers: Engineering Sustainability, ISSN 1478-4637, E-ISSN 1751-7664, Vol. 163, nr 1, s. 19-29Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The static and dynamic response of a long-span arch soil–steel composite railway bridge is studied. The bridge has a span of 11 m and a rise of 4·3 m. Two field tests were carried out before and after the first winter. Strains and displacements were measured during passages of a locomotive at different speeds. Vertical ballast accelerations and the effects of braking forces were also measured. The measurements indicated that the speed of the vehicle had a large influence on the displacements, thrusts and moments. The structure was found to be safe when measured values of moments and thrusts were compared with live load calculations according to design codes. It is concluded that the dynamic amplification factors calculated from the tests were larger than the theoretical values according to bridge design codes. However, there are indicators of post-winter effects in the form of reduced dynamic amplification factors.

  • 22.
    Bayoglu Flener, Esra
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Brobyggnad inkl stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Brobyggnad inkl stålbyggnad.
    Testing the static and dynamic behaviour of a soilsteel bridgeManuskript (preprint) (Annet vitenskapelig)
  • 23.
    Bayoglu Flener, Esra
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Brobyggnad inkl stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Brobyggnad inkl stålbyggnad.
    Sundquist, Håkan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Brobyggnad inkl stålbyggnad.
    Field testing of a long-span arch steel culvert during backfilling and in service2005Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 1, nr 3, s. 181-188Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The paper presents the first part of the in-situ measurements and data analyses for the tests conducted during backfilling and during service of a long-span corrugated steel culvert railway bridge over Skivarpsan, Rydsgard, Sweden. Static and dynamic tests were carried out measuring strains and displacements. Temperature readings were taken along with the measurements. Comparisons of moments during compaction showed that there is good agreement between test results and theoretical values. The theoretical calculation of the rise of the crown during compaction and the crown moments due to live load seem to be conservative, while the theoretical axial forces agree reasonably with the measured axial forces.

  • 24.
    Bayoğlu Flener, Esra
    et al.
    Uppsala University, division of Construction Engineering.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Evaluation of the dynamic response of a soil-steel composite railway bridge2012Inngår i: Archives of Institute of Civil Engineering, 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The dynamic response of a long-span arch soil-steel composite railway bridge is studied. The bridge has a span of 11 m and a rise of 4.3 m. Strains, displacements and vertical ballast accelerations were measured during passages of a locomotive at different speeds. The results indicate that the speed of the locomotive has a large influence on the displacements, thrusts and moments. The structure was found to be safe when measured values of moments and thrusts were compared with the live load calculations according to design codes. However, dynamic amplification factors as high as 1.45 were obtained for the moments at the quarter point and this is found to be much greater than the values specified in bridge design codes. Despite this, due to the high damping involved, bridges of this kind are believed to be less sensitive to resonance problems from passing trains.

  • 25.
    Beygi, H.
    et al.
    KTH.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Vibration control of a high-speed railway bridge using multiple tuned mass dampers2016Inngår i: IABSE Congress Stockholm, 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, International Association for Bridge and Structural Engineering (IABSE) , 2016, s. 2519-2526Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In the current article, the Banafjäl Bridge located on the Bothnia line (Botniabanan) in northern Sweden is studied. The bridge is a 40m long composite ballasted high-speed railway bridge. A 3D FE model of the bridge was developed using the commercial FE software, Abaqus. The FE model was calibrated against the measured data of the bridge. The dynamic response of the bridge's FE model was investigated under the dynamic load of the passing HSLM-A trains using modal dynamic analysis. The vertical acceleration induced by excitation of the passing train exceeded the permissible limit of 3.5 m/s2 for the speed range of 220-240 km/h. Thus, damping solutions using multiple tuned mass dampers (MTMDs) were investigated. According to the results of this study, a 4 tonnes MTMD system consisting of 5 parallel TMDs attached to the mid-span of the bridge could effectively control the undesired vibration of the bridge in both warm and cold seasons.

  • 26. Cahill, Paul
    et al.
    Hazra, Budhaditya
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Mathewson, Alan
    Pakrashi, Vikram
    Vibration energy harvesting based monitoring of an operational bridge undergoing forced vibration and train passage2018Inngår i: Mechanical systems and signal processing, ISSN 0888-3270, E-ISSN 1096-1216, Vol. 106, s. 265-283Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The application of energy harvesting technology for monitoring civil infrastructure is a bourgeoning topic of interest. The ability of kinetic energy harvesters to scavenge ambient vibration energy can be useful for large civil infrastructure under operational conditions, particularly for bridge structures. The experimental integration of such harvesters with full scale structures and the subsequent use of the harvested energy directly for the purposes of structural health monitoring shows promise. This paper presents the first experimental deployment of piezoelectric vibration energy harvesting devices for monitoring a fullscale bridge undergoing forced dynamic vibrations under operational conditions using energy harvesting signatures against time. The calibration of the harvesters is presented, along with details of the host bridge structure and the dynamic assessment procedures. The measured responses of the harvesters from the tests are presented and the use the harvesters for the purposes of structural health monitoring (SHM) is investigated using empirical mode decomposition analysis, following a bespoke data cleaning approach. Finally, the use of sequential Karhunen Loeve transforms to detect train passages during the dynamic assessment is presented. This study is expected to further develop interest in energy harvesting based monitoring of large infrastructure for both research and commercial purposes.

  • 27. Cahill, Paul
    et al.
    Nuallain, Nora Aine Ni
    Jackson, Nathan
    Mathewson, Alan
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Pakrashi, Vikram
    Energy Harvesting from Train-Induced Response in Bridges2014Inngår i: Journal of Bridge Engineering, ISSN 1084-0702, E-ISSN 1943-5592, Vol. 19, nr 9, s. 04014034-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The integration of large infrastructure with energy-harvesting systems is a growing field with potentially new and important applications. The possibility of energy harvesting from ambient vibration of bridges is a new field in this regard. This paper investigates the feasibility of energy harvesting for a number of trains considering their passage over a bridge. The power that can be derived from an energy-harvesting device due to a train crossing a bridge at different speeds is compared against typical demands of small wireless devices and is found to be adequate for powering such devices. These estimates of harvested energy also relate to the individual signatures of trains. In this work, the modeled dynamic responses of a bridge traversed by trains are compared against full-scale experimental analysis of train-bridge interactions. A potential application in structural health monitoring (SHM) using energy harvesting has also been demonstrated and compared with laboratory experimental data. Consistent and monotonic damage calibration curves have been constructed using estimated harvested energy.

  • 28.
    Cantero, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Roughan & O’Donovan Innovative Solutions, Dublin, Ireland.
    Arvidsson, Therese
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    O'Brien, Eugene
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Train–track–bridge modelling and review of parameters2016Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 12, nr 9, s. 1051-1064Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study gathers all necessary information to construct a model to calculate the coupled dynamic response of train–track–bridge systems. Each component of the model is presented in detail together with a review of possible sources for the parameter values, including a collection of vehicle models, a variety of track configurations and general railway bridge properties. Descriptions of the most important track irregularity representations are also included. The presented model is implemented in MATLAB and validated against a commercially available finite element package for a range of speeds, paying particular attention to a resonant speed. Finally, the potential of the described model is illustrated with two numerical studies that address interesting aspects of train and bridge dynamic responses. In particular, the effect of the presence of a vehicle on the bridge’s fundamental frequency is studied, as well as the influence of the wavelength of the rail irregularities on the dynamic effects of the bridge and the vehicle.

  • 29.
    Cantero, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap. Roughan and O'Donovan Innovative Solutions, Ireland.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Numerical evaluation of the mid-span assumption in the calculation of total load effects in railway bridges2016Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 107, s. 1-8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Maximum load effects in simply supported railway bridges traversed by trains are generally investigated at the mid-span section. However, this assumption is not necessarily correct. The true maximum load effect might occur at some other bridge section and its magnitude could be significantly greater. This paper quantifies the underestimation of the load effects as a result of exclusively considering the middle section, with special emphasis on resonant situations. A 2D numerical model of a vehicle-track-bridge system was used to evaluate different vehicle velocities, bridge properties and track irregularity conditions. The error due to the mid-span assumption depends on the particular case considered but can be related to the relative energy content of the higher modes of vibration. The results show that the error is greatest for accelerations, smaller for bending moments and is almost negligible for displacements.

  • 30.
    Cantero, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Gonzalez, Arturo
    The Virtual Axle concept for detection of localised damage using Bridge Weigh-in-Motion data2015Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 89, s. 26-36Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes a new level I damage identification method for short span statically indeterminate bridges using the information provided by a Bridge Weigh-in-Motion system. Bridge Weigh-in-Motion systems measure the bridge deformation due to the crossing of traffic to estimate traffic attributes, namely axle weights and distances between axles for each vehicle. It is theoretically shown that it is convenient to introduce a fictitious weightless axle, which has been termed 'Virtual Axle', in the Bridge Weigh-in-Motion calculations to derive a damage indicator. The latter can be used both as a new robust output-only model-free level I Structural Health Monitoring technique and as a new self-calibration method for Bridge Weigh-in-Motion systems. The response of a fixed-fixed beam traversed by a 2-axle vehicle travelling over an irregular profile is used to validate the proposed method. By means of Monte Carlo simulation the influence of the key parameters such as the degree and location of damage, noise levels, span lengths and profile irregularities on the accuracy of the method are investigated. The results show that the 'Virtual Axle' method is able to detect small local damages in statically indeterminate structures.

  • 31.
    Cantero, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Roughan & O'Donovan Innovative Solutions, Ireland.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    OBrien, Eugene
    Maximum total load effects in Vehicle-Bridge dynamic interaction problems for simply supported structures2014Inngår i: Proceedings of the 9th International Conference on Structural Dynamics, EURODYN 2014, 2014, s. 1169-1174Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper quantifies the underestimation of bending moment that results from exclusively considering the midspansection of bridges when calculating vehicle-bridge dynamic interaction. A numerical model of a simply supported Euler-Bernoulli beam, traversed by a 1-DOF vehicle, is used to evaluate the differences. The simplicity of the model is justified by theadditional insight that the results provide on the complex vehicle-bridge interaction problem. The results are presented usingthree dimensionless parameters that uniquely define the solution, taking into account the coupled system (vehicle and beam)frequencies and masses as well as the velocity of the passing vehicle. The results show that the overall maximum load effectoccurs in the vicinity of the mid-span section and can be of significantly higher magnitude when compared to the maximum atmid-span.

  • 32.
    Cantero, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    OBrien, Eugene
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Extending the Assessment Dynamic Ratio to Railway Bridges2014Inngår i: Proceedings of the Second International Conference on Railway Technology: Research, Development and Maintenance, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents an alternative site-specific dynamic allowance factor for railwaybridges. It is calculated numerically using a model that allows for train–bridgeinteraction and takes into account the track irregularities. A wide range of short tomedium span bridges are studied while allowing for uncertainties associated withthe traffic configuration and vehicle properties within a Monte Carlo analysis. Theresults clearly show that a smaller recommended allowance for dynamics can besafely defined, which in turn can prevent unnecessary repair or replacement ofexisting bridges.

  • 33.
    Cantero, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap. Arena House, Ireland.
    Ülker-Kaustell, Mahir
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap. Tyréns AB, Sweden.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Time-frequency analysis of railway bridge response in forced vibration2016Inngår i: Mechanical systems and signal processing, ISSN 0888-3270, E-ISSN 1096-1216, Vol. 76-77, s. 518-530Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper suggests the use of the Continuous Wavelet Transform in combination with the Modified Littlewood-Paley basis to analyse bridge responses exited by traversing trains. The analysis provides an energy distribution map in the time-frequency domain that offers a better resolution compared to previous published studies. This is demonstrated with recorded responses of the Skidträsk Bridge, a 36 m long composite bridge located in Sweden. It is shown to be particularly useful to understand the evolution of the energy content during a vehicle crossing event. With this information it is possible to distinguish the effect of several of the governing factors involved in the dynamic response including vehicle's speed and axle configuration as well as non-linear behaviour of the structure.

  • 34.
    Cantero Lauer, Daniel
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Total load effects of portal frame bridges in high-speed railway lines2015Inngår i: Conference Proceedings of the Society for Experimental Mechanics Series, Society for Experimental Mechanics , 2015, s. 107-116Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper studies the maximum total load effects of short span portal frame railway bridges when traversed by high-speed trains. It is generally assumed that in single span bridges the maximum stresses, displacements and accelerations occur at the mid-span section. However, this in not necessarily correct and the maximum might be located in a wide area around the mid-span. This study aims to quantify the underestimation of the mid-span assumption when calculating maximum load effects. A numerically validated 2D Vehicle-Bridge Interaction model is used to analyze the stresses, displacements and accelerations that develop during the passage of high-speed trains. These load effects are studied along the full length of the structure and compared to the maximum obtained at the mid-span section. Particular attention is given to the resonant speeds near the operational speeds of high-speed railways. The results show that significantly higher load effects can be expected. The presented study is the preliminary work for deciding on the optimum configuration of empirical field tests.

  • 35.
    Carlsson, Fredrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Probabilistisk analys av Ölandsbron baserad på fordonens verkliga laster och sidopositioner2008Rapport (Annet vitenskapelig)
  • 36.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Environmental comparison of a railway bridge with alternative designs2012Inngår i: fib Symp.: Concr. Struct. Sustainable Community - Proc., 2012, s. 353-356Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Railway bridges are complex structures that remain for a long life span and consume large amount of material and energy throughout the life span. All of those lead to considerable resource depletion and environmental burdens. Life Cycle Assessment (LCA) has proved to be a comprehensive tool for quantifying and assessing the environmental impacts of the products through its whole life cycle. This paper presents a comparative case study between two alternative designs of Banafjäl Bridge: ballast track design and fixed slab track design. The methodology of LCA is utilized as a supporting tool. The assessment considers the key environmental category of global warming potential from 'cradle to gate', which covers the material production and distribution process. The result shows that the fixed-slab design indicates a better environmental performance than the ballast track design.

  • 37.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Environmental life cycle assessment comparison between two bridge types: reinforced concrete bridge and steel composite bridge2013Inngår i: Third International Conference on Sustainable Construction Materials and Technologies, 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The concept of sustainable construction has attracted an increased attention. Bridge infrastructures and their belonged construction activities consume considerable material and energy, which is responsible for large environmental burdens. However, the environmental assessment of bridges has not been integrated into the decision-making process. This paper presents a systematic LCA method for quantifying the environmental impacts for bridges. The comparison study is performed between a reinforced concrete bridge and a steel bridge as an alternative design, with several key maintenance and EOL scenarios outlined. LCA study is performed with the ReCiPe methodology with life cycle inventories data from public database. Five selected mid-point level impact categories and the energy consumption are presented. The result shows that the steel bridge has a better environmental performance due to the recycling strategy, while the initial material manufacture is the most dominant phase that contributes large environmental impact in both design solutions.

  • 38.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad (byte av engelskt namn 20110630).
    LCA of Railway Bridge: a comparison between two superstructure designs2013Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 9, nr 11, s. 1149-1160Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Railway bridges currently encounter the challenges of increasing the load capacity while the environmental sustainability should be achieved. However, it has been realised that the environmental assessment of railway bridges has not been integrated into the decision-making process, the standard guideline and criterion is still missing in this field. Therefore, the implementation of life cycle assessment (LCA) method is introduced into railway bridges. This article provides a systematic bridge LCA model as a guideline to quantify the environmental burdens for the railway bridge structures. A comparison case study between two alternative designs of Banafjäl Bridge is further carried out through the whole life cycle, with the consideration of several key maintenance and end-of-life scenarios. Six impact categories are investigated by using the LCA CML 2001 method and the known life cycle inventory database. Results show that the fixed-slab bridge option has a better environmental performance than the ballasted design due to the ease of maintenances. The initial material manufacture stage is responsible for the largest environmental burden, while the impacts from the construction machinery and material transportations are ignorable. Sensitivity analysis illustrates the maintenance scenario planning and steel recycling have the significant influence on the final results other than the traffic disturbances.

  • 39.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Life cycle assessment framework for railway bridges: literature survey and critical issues2014Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 10, nr 3, s. 277-294Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Currently, the whole world is confronted with great challenges related to environmental issues. As a fundamental infrastructure in transport networks, railway bridges are responsible for numerous material and energy consumption through their life cycle, which in turn leads to significant environmental burdens. However, present management of railway bridge infrastructures is mainly focused on the technical and financial aspects, whereas the environmental assessment is rarely integrated. Life cycle assessment (LCA) is deemed as a systematic method for also assessing the environmental impact of products and systems, but its application in railway bridge infrastructures is rare. Very limited literature and research studies are available in this area. In order to incorporate the implementation of LCA into railway bridges and set new design criteria, this article performs an elaborate literature survey and presents current developments regarding the LCA implementation for railway bridges. Several critical issues are discussed and highlighted in detail. The discussion is focused on the methodology, practical operational issues and data collections. Finally, a systematic LCA framework for quantifying environmental impacts for railway bridges is introduced and interpreted as a potential guideline.

  • 40.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Pettersson, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Skanska.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Evaluating the life cycle environmental impact of short span bridges2016Inngår i: IABSE Congress Stockholm, 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, International Association for Bridge and Structural Engineering (IABSE) , 2016, s. 1701-1707Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Bridge infrastructure consumes large amount of energy and raw materials, leading to considerable environmental burdens. The traditional infrastructure construction prioritizes its technical and economic viability. In recent years, the society devotes an ever-increased attention to the environmental impact of the construction sector. Life cycle assessment (LCA) is a systematic method for assessing the environmental impact of products and systems, but its application in bridges is scarce. In Swede, most of the bridges are short spans and the type of concrete slabframe bridge (CFB) accounts for a large share. Soil steel composite bridge (SSCB) is a functional equivalent solution for CFB. In order to mitigate the environmental burdens of short span bridges, this paper performed a comparative LCA study between these two types of bridge. The results indicate that the initial material consumption is critical through the whole life cycle. The case of SSCB shows preferable environmental performance over CFB in most of the examined indicators.

  • 41.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Pettersson, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Life cycle environmental impact of two commonly used short span bridges in SwedenManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    In a bridge project, several alternative designs can be functionally equivalent for the designated location. The environmental concern urges today’s designers to explore the new design options to mitigate the associated environmental burdens. When comparing to the concrete slab frame bridges, the soil-steel flexible culverts show advantages in ease erection, low maintenance as well as the competitive cost. However, its environmental performance has never been studied. This paper compared the environmental performance of these two bridge types through the whole life cycle from cradle to grave, based on 8 real cases in Sweden. Unlike the previous studies that only looked at few indicators, this paper comprehensively covered eleven sets of mid-point indicators, cumulative energy demand (CED) as well as the associated cost. The construction phase is a specific focus in this paper. The results indicate that the environmental performance of a bridge is linked closely with the bridge type selection, as well as governed by multiple indicators in the environmental domain. 

  • 42.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. KTH Royal Inst Technol, Div Struct Engn & BridgAalborg Univ, Danish Bldg Res Inst, Copenhagen, Denmark.
    Pettersson, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Soil-steel composite bridge: An alternative design solution for short spans considering LCA2018Inngår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 189, s. 647-661Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a bridge project, several alternative design solutions can be functionally equivalent for the designated location. Today's bridge constructions highly rely on the non-renewable resources, the consumption of fossil fuels, and the intensive usage of concrete. This urges designers to explore the new design options to mitigate the associated environmental burdens. When comparing to the concrete slab frame bridges (CFB), the soil-steel flexible culverts (or soil-steel composite bridge, SSCB) show advantages in ease erection, low maintenance as well as the competitive cost. However, its environmental performance has never been studied. This paper intends to compare the environmental performance of these two bridge types through the whole life cycle, based on 8 selected cases in Sweden. Unlike previous studies only limited to few impact indicators, this study comprehensively covers a wide range of indicators: including eleven types of mid-point impact categories, the cumulative energy demand (CED) and the associated cost. The construction phase, which seldom included previously, is a specific focus in this paper. The results find that: 1) the SSCBs show advantages over the CFBs in most of the investigated indicators; 2) the construction phase, when explicitly evaluated, may take up to 34% of the total life cycle environmental burdens; 3) the environmental performance of a bridge is closely linked with the bridge type selection, multiple indicators in the environmental domain, designers' preference, the construction phase, as well as the time schedule constraints.

  • 43.
    Du, Guangli
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Safi, Mohammed
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. ÅF Infrastructure AB, Sweden.
    Pettersson, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Skanska Sverige AB, Sweden.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Life cycle assessment as a decision support tool for bridge procurement: environmental impact comparison among five bridge designs2014Inngår i: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 19, nr 12, s. 1948-1964Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The conventional decision-making for bridges is mostly focusing on technical, economical, and safety perspectives. Nowadays, the society devotes an ever-increased effort to the construction sector regarding their environmental performance. However, considering the complexity of the environmental problems and the diverse character of bridges, the related research for bridge as a whole system is very rare. Most existing studies were only conducted for a single indicator, part of the structure components, or a specific life stage. Life Cycle Assessment (LCA) is an internationally standardized method for quantifying the environmental impact of a product, asset, or service throughout its whole life cycle. However, in the construction sector, LCA is usually applied in the procurement of buildings, but not bridges as yet. This paper presents a comprehensive LCA framework for road bridges, complied with LCA ReCiPe (H) methodology. The framework enables identification of the key structural components and life cycle stages of bridges, followed by aggregation of the environmental impacts into monetary values. The utility of the framework is illustrated by a practical case study comparing five designs for the Karlsnas Bridge in Sweden, which is currently under construction. This paper comprehensively analyzed 20 types of environmental indicators among five proposed bridge designs, which remedies the absence of full spectrum of environmental indicators in the current state of the art. The results show that the monetary weighting system and uncertainties in key variables such as the steel recycling rate and cement content may highly affect the LCA outcome. The materials, structural elements, and overall designs also have varying influences in different impact categories. The result can be largely affected by the system boundaries, surrounding environment, input uncertainties, considered impact indicators, and the weighting systems applied; thus, no general conclusions can be drawn without specifying such issues. Robustly evaluating and ranking the environmental impact of various bridge designs is far from straightforward. This paper is an important attempt to evaluate various designs from full dimensions. The results show that the indicators and weighting systems must be clearly specified to be applicable in a transparent procurement. This paper provides vital knowledge guiding the decision maker to select the most LCA-feasible proposal and mitigate the environmental burden in the early stage.

  • 44.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    A review of recent development in structural health monitoring of bridgesManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Bridges are expensive to manage as they require thorough inspection and maintenance operations. Meanwhile the development of Structural Health Monitoring (SHM) techniques in recent years have demonstrated the potential for this to become a tool that bridge managers can use to optimise inspection and maintenance procedures. This paper reviews recent development in SHM and damage detection techniques. The paper focuses on recent algorithms developed or adapted for damage detection and structural health monitoring in bridge structures, although some of the algorithms presented might be of a more general nature or developed for other kind of structures. The algorithms presented are classified according to the method they use for damage detection and location into Acoustic Emission, Modal Analysis and Statistical pattern recognition based.

     

  • 45.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Analysis of the annual variations in the dynamic behavior of a ballasted railway bridge using Hilbert transform2014Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 60, s. 126-132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper the variations in dynamic properties (eigenfrequency and damping) due to seasonal effects of a single span, ballasted railway bridge are studied. It is demonstrated that both the eigenfrequency and characteristic damping vary importantly with environmental conditions and amplitude of vibration. For this, acceleration signals corresponding to roughly a year of monitoring are analyzed with the Hilbert transform and the instantaneous frequency and equivalent viscous damping ratio are calculated during the free vibrations. Over 1000 trains passages were analyzed, with temperatures ranging from -30 to +30°C and amplitudes of vibration varying from 0.5m/s2 to 0. The location of the accelerometers allowed for separation of the signals into their bending and torsional components. It was found that during the cold season, with months of temperatures below 0°C, the dynamic properties varied the most. Not only did the frequencies (for small vibrations) differ more than 9% even for a given temperature, but the non-linearity present in the structure did also change in a matter of hours. These findings are important in the context of Structural Health Monitoring. Any system that aims at warning early in the onset of damage by analyzing changes in the dynamic characteristic of a structure needs to first fully understand and account for the natural variability of these parameters, often much larger than what could be expected from reasonable levels of damage.

  • 46.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    BMIM Aided Damage Detection in Bridges Using Machine Learning2013Manuskript (preprint) (Annet vitenskapelig)
  • 47.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    BWIM aided damage detection in bridges using machine learning2015Inngår i: Journal of Civil Structural Health Monitoring, ISSN 2190-5452, Vol. 5, nr 5, s. 715-725Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, a new, model-free damage detection method is proposed and validated on a simple numerical experiment. The proposed algorithm used vibration data (deck accelerations) and bridge weigh-in-motion data (load magnitude and position) to train a two-stage machine learning setup to classify the data into healthy or damaged. The proposed method is composed in its first stage of an artificial neural network and on the second stage of a gaussian process. The proposed method is applicable to railway bridges, since it takes advantage of the fact that vehicles of known axle configuration cross the bridge regularly, that normally only one train is on the bridge at a time and that the lateral positioning of the loads does not change. The novelty of the proposed algorithm is that it makes use of the data on the load’s position, magnitude and speed that can be obtained from a Bridge Weigh-in-Motion system to improve the accuracy of the damage detection algorithm.

  • 48.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Continous monitoring of bearing forces and displacements in the High Coast Bridge2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The High Coast Bridge is a four lane, 1867 m long suspension bridge located in middle Sweden. The bridge, constructed between 1993 and 1997, comprises a multiple cell steel box girder with a main span of 1210 m. The girder is fully suspended along its entire length without any bearings at the pylons. Because of the unexpected wear in the sliding bearings at its ends a monitoring program was initiated. The program included the dynamic monitoring of the longitudinal displacement of the girder and bearing forces at both bearings in the northern abutment. It also included the monitoring of hanger forces at the hangers closest to the northern end and the monitoring of road traffic entering and leaving the bridge by means of a traffic camera located at that same end. In this study the long term behavior of the bridge, as observed by the monitoring system, is studied and presented including the effects of seasonal temperature changes. Furthermore the capabilities of the installed monitoring system for measuring traffic loads, as a Bridge Weigh in Motion system, in conjunction with the camera are explored and the result of the traffic monitoring is presented. The monitoring system was found capable of estimating the total loads of trucks crossing the bridge, as well as the total distance travelled by the bearing, both important parameters for estimating bearing wear. Furthermore, with the aid of the camera to discern between single and multiple truck events, overloaded trucks could be identified by the system.

  • 49.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Continuous monitoring of bearing forces and displacements in the High Coast BridgeManuskript (preprint) (Annet vitenskapelig)
  • 50.
    Gonzalez, Ignacio
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Karoumi, Raid
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Continuous monitoring of bearing forces and displacements  on the high coast suspension bridgeManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    This paper presents results from the longitudinal girder displacement and bearing force monitoring on a highway suspension bridge located in Sweden. The monitoring programme was initiated in 2005 by the bridge owner after the discovery of unusual and intense wear in the Teflon layers of the bearings. The initial work focused mainly on a long term monitoring of the bearing forces in the northern abutment. After the first monitoring period of one year the monitoring system was enhanced with a traffic camera, a temperature sensor and accelerometers mounted on the two hangers closest to the instrumented bearing. The monitoring period presented in this paper covers ten months from February to December 2010 and focuses on the horizontal displacement of the girder and on the forces registered in the north-west bearing in conjunction with the traffic information provided by the traffic camera.

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