Change search
Link to record
Permanent link

Direct link
BETA
Alternative names
Publications (10 of 149) Show all publications
Rådeström, S., Ülker-Kaustell, M., Andersson, A., Tell, V. & Karoumi, R. (2016). Application of fluid viscous dampers to mitigate vibrations of high-speed railway bridges. International Journal of Rail transportation, 1-16.
Open this publication in new window or tab >>Application of fluid viscous dampers to mitigate vibrations of high-speed railway bridges
Show others...
2016 (English)In: International Journal of Rail transportation, ISSN 2324-8378, E-ISSN 2324-8386, 1-16 p.Article in journal (Refereed) Published
Abstract [en]

Several bridges along the Bothnia railway line in Sweden do not fulfil the Eurocode requirements regarding the maximum vertical bridge deck acceleration. The aim of this study is to investigate the possibility of reducing the acceleration of one of these bridges to an acceptable level by using post-installed viscous dampers. The bridge-damper system is described by a single-degree-of-freedom model. Assuming that the dampers do not change the mode shapes of the bridge, the model is further generalized to include higher order bending modes. The dampers are connected between the bottom surface of the bridge deck and the abutments. This creates an eccentricity between the connection point of the dampers and the neutral axis of the bridge, which is found to have a significant influence on the efficiency of the dampers. The results of this study also indicate that the proposed retrofit method can reduce the accelerations to an acceptable level.

Place, publisher, year, edition, pages
Taylor & Francis Group, 2016
Keyword
fluid viscous dampers, high-speed trains, passive damping, railway bridges, resonance, Structural dynamics
National Category
Infrastructure Engineering
Identifiers
urn:nbn:se:kth:diva-197137 (URN)10.1080/23248378.2016.1209444 (DOI)000396621000004 ()2-s2.0-84978485268 (Scopus ID)
Note

QC 20161213

Available from: 2016-12-13 Created: 2016-11-30 Last updated: 2017-11-29Bibliographically approved
Jaksic, V., Mandic, D. P., Karoumi, R., Basu, B. & Pakrashi, V. (2016). Estimation of nonlinearities from pseudodynamic and dynamic responses of bridge structures using the Delay Vector Variance method. Physica A: Statistical Mechanics and its Applications, 441, 100-120, Article ID 16342.
Open this publication in new window or tab >>Estimation of nonlinearities from pseudodynamic and dynamic responses of bridge structures using the Delay Vector Variance method
Show others...
2016 (English)In: Physica A: Statistical Mechanics and its Applications, ISSN 0378-4371, E-ISSN 1873-2119, Vol. 441, 100-120 p., 16342Article in journal (Refereed) Published
Abstract [en]

Analysis of the variability in the responses of large structural systems and quantification of their linearity or nonlinearity as a potential non-invasive means of structural system assessment from output-only condition remains a challenging problem. In this study, the Delay Vector Variance (DVV) method is used for full scale testing of both pseudo-dynamic and dynamic responses of two bridges, in order to study the degree of nonlinearity of their measured response signals. The DVV detects the presence of determinism and nonlinearity in a time series and is based upon the examination of local predictability of a signal. The pseudo-dynamic data is obtained from a concrete bridge during repair while the dynamic data is obtained from a steel railway bridge traversed by a train. We show that DVV is promising as a marker in establishing the degree to which a change in the signal nonlinearity reflects the change in the real behaviour of a structure. It is also useful in establishing the sensitivity of instruments or sensors deployed to monitor such changes.

Place, publisher, year, edition, pages
Elsevier, 2016
Keyword
Bridge, Condition monitoring, Delay Vector Variance (DVV), Instrumentation, Signal nonlinearity, System identification, Bridges, Identification (control systems), Bridge structures, Degree of non-linearity, Delay vector variances, Full-scale testing, Pseudo-dynamics, Steel railway bridge, Structural systems, Dynamic response
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-177739 (URN)10.1016/j.physa.2015.08.026 (DOI)2-s2.0-84941928815 (Scopus ID)
Note

QC 20151130

Available from: 2015-11-30 Created: 2015-11-25 Last updated: 2017-12-01Bibliographically approved
Du, G., Pettersson, L. & Karoumi, R. (2016). Evaluating the life cycle environmental impact of short span bridges. In: IABSE Congress Stockholm, 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment. Paper presented at 19th IABSE Congress Stockholm 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, 21 September 2016 through 23 September 2016 (pp. 1701-1707). International Association for Bridge and Structural Engineering (IABSE).
Open this publication in new window or tab >>Evaluating the life cycle environmental impact of short span bridges
2016 (English)In: 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, 1701-1707 p.Conference paper (Refereed)
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.

Place, publisher, year, edition, pages
International Association for Bridge and Structural Engineering (IABSE), 2016
Keyword
Climate change, CO2 emission, Concrete slab frame bridge, Global warming, LCA, Life cycle assessment, Soil steel composite bridge, Soil steel flexible culverts, Sustainable construction, Bridges, Carbon dioxide, Composite bridges, Concrete slabs, Concretes, Construction industry, Environmental impact, Environmental management, Soils, Steel bridges, Sustainable development, Bridge infrastructure, Environmental performance, Infrastructure construction, Life Cycle Assessment (LCA), Life-cycle environmental impact, Slab frames, Steel composite bridges, Life cycle
National Category
Civil Engineering
Identifiers
urn:nbn:se:kth:diva-216882 (URN)2-s2.0-85018989725 (Scopus ID)9783857481444 (ISBN)
Conference
19th IABSE Congress Stockholm 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, 21 September 2016 through 23 September 2016
Note

Conference code: 127207; Export Date: 24 October 2017; Conference Paper. QC 20171107

Available from: 2017-11-07 Created: 2017-11-07 Last updated: 2017-11-07Bibliographically approved
Wadi, A., Pettersson, L. & Karoumi, R. (2016). Flexible culverts in sloping terrain: Numerical simulation of avalanche load effects. Cold Regions Science and Technology, 124, 95-109.
Open this publication in new window or tab >>Flexible culverts in sloping terrain: Numerical simulation of avalanche load effects
2016 (English)In: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 124, 95-109 p.Article in journal (Refereed) Published
Abstract [en]

Avalanche protection concrete structures are expensive and their construction period is often influenced by the climatological conditions at site, which could result in prolonging the erection process and increase its associated costs. Given the short construction time of flexible culverts, such structures can be a cost-effective alternative to traditional protective measures. This article investigates the performance of flexible culverts - often referred to as soil-steel composite bridges (SSCB) - when constructed in sloping topography under avalanche loads. A number of 2D finite element models were created to simulate two case studies composed of a pipe arch and a high-profile arch. The models were generated to investigate the effect of soil cover depth, the avalanche proximity, and the change in soil support conditions around the conduit. The aim was to perceive and understand the changes in deformations and sectional forces under defined avalanche loads. The results enable to realise the effect of shallow soil covers in the pronounced change in bending moments due to avalanches. The proximity of avalanche deviation point has a great influence on the structural performance, though increasing the soil cover depth could considerably help in reducing the bending moments resulting from avalanches. It is also found that the downhill soil support configuration has a substantial effect on the flexural response of the structure.

Place, publisher, year, edition, pages
Elsevier, 2016
Keyword
Flexible culvert, Soil-steel composite bridge, Sloping terrain, Finite element model, Avalanche load, Snowshed
National Category
Civil Engineering
Identifiers
urn:nbn:se:kth:diva-184521 (URN)10.1016/j.coldregions.2016.01.003 (DOI)000371903000009 ()2-s2.0-84956901137 (Scopus ID)
Note

QC 20160407

Available from: 2016-04-07 Created: 2016-04-01 Last updated: 2017-11-30Bibliographically approved
Veganzones Muñoz, J. J., Pettersson, L., Sundqvist, H. & Karoumi, R. (2016). Life-cycle cost analysis as a tool in the developing process for new bridge edge beam solutions. Structure and Infrastructure Engineering, 12(9), 1185-1201.
Open this publication in new window or tab >>Life-cycle cost analysis as a tool in the developing process for new bridge edge beam solutions
2016 (English)In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 12, no 9, 1185-1201 p.Article in journal (Refereed) Published
Abstract [en]

Currently in Sweden, the life-cycle measures applied on bridge edge beams may take up to 60% of the total costs incurred along the road bridges’ life span. Moreover, significant disturbances for the road users are caused. Therefore, the Swedish Transport Administration has started a project to develop alternative edge beam design solutions that are better for society in terms of cost. The purpose of this article is to investigate whether these proposals can qualify for more detailed studies through an evaluation and comparison based on a comprehensive life-cycle cost analysis. The alternatives including the standard design are applied to typical Swedish bridges. The impact of the values of the parameters with the largest influence is investigated by sensitivity analyses. Results with different life-cycle strategies are shown. The positive influences in the total life-cycle cost of a stainless steel reinforced solution and of the enhanced construction technique are estimated. The concrete edge beam integrated with the deck seems to be favourable, which is in line with international experience observed. Different designs may be appropriate depending on the bridge case and the life-cycle strategy. The Swedish Transport Administration will carry out a demonstration project in a bridge with one of the proposals.

Place, publisher, year, edition, pages
Taylor & Francis, 2016
Keyword
bridge decks, bridge edge beam system, bridge maintenance, bridges, edge beams, infrastructure planning, Life-cycle costs, sensitivity analysis
National Category
Infrastructure Engineering
Identifiers
urn:nbn:se:kth:diva-181806 (URN)10.1080/15732479.2015.1095770 (DOI)000379180200014 ()2-s2.0-84955124708 (Scopus ID)
Note

QC 20160812

Available from: 2016-02-04 Created: 2016-02-04 Last updated: 2017-11-30Bibliographically approved
Cantero, D. & Karoumi, R. (2016). Numerical evaluation of the mid-span assumption in the calculation of total load effects in railway bridges. Engineering structures, 107, 1-8.
Open this publication in new window or tab >>Numerical evaluation of the mid-span assumption in the calculation of total load effects in railway bridges
2016 (English)In: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 107, 1-8 p.Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
Elsevier, 2016
Keyword
Bridge, Dynamic, Railway, Resonance, Mid-span, Acceleration
National Category
Civil Engineering
Identifiers
urn:nbn:se:kth:diva-180477 (URN)10.1016/j.engstruct.2015.11.005 (DOI)000366775600001 ()2-s2.0-84946866203 (Scopus ID)
Note

QC 20160115

Available from: 2016-01-15 Created: 2016-01-14 Last updated: 2017-11-30Bibliographically approved
Rådeström, S., Andersson, A., Mahir, Ü.-K., Tell, V. & Karoumi, R. (2016). Structural control of high-speed railway bridges by means of fluid viscous dampers. In: 19th IABSE Congress 2016: . Paper presented at 19th IABSE Congress on Challenges in Design and Construction of an Innovative and Sustainable Built Environment (pp. 2535-2542). Zürich, Switzerland.
Open this publication in new window or tab >>Structural control of high-speed railway bridges by means of fluid viscous dampers
Show others...
2016 (English)In: 19th IABSE Congress 2016, Zürich, Switzerland, 2016, 2535-2542 p.Conference paper, Published paper (Other academic)
Abstract [en]

The dynamic response of structures is an important aspect to consider, especially at resonance. Particularly, bridges traversed by trains are at risk, due to the repeated loading with regular interval from the axle and bogie spacings. If the risk of resonance is not accounted for in the design, the vertical acceleration of the bridge deck may exceed the allowed limits of comfort and safety. Hence, alternative, sustainable measures for reducing the vibrations in bridges are required to solve these challenges. This paper presents studies of fluid viscous dampers used to control the dynamic behaviour of high-speed railway bridges. A finite element model is used to investigate the response of an existing bridge, both prior to and after the installation of dampers, and the influence of some parameters on the efficiency of the dampers are analysed. The results from this paper show that the vertical deck acceleration is sufficiently reduced using the proposed solution.

Place, publisher, year, edition, pages
Zürich, Switzerland: , 2016
Keyword
resonance, dynamic response, vibrations, bridges, high-speed trains, damper retrofit
National Category
Other Civil Engineering
Research subject
Civil and Architectural Engineering
Identifiers
urn:nbn:se:kth:diva-205648 (URN)2-s2.0-85018996459 (Scopus ID)978-3-85748-144-4 (ISBN)
Conference
19th IABSE Congress on Challenges in Design and Construction of an Innovative and Sustainable Built Environment
Funder
Swedish Research Council Formas, 2010-1084
Note

QC 20170425

Available from: 2017-04-21 Created: 2017-04-21 Last updated: 2017-11-28Bibliographically approved
Solat Yavari, M., Pacoste-Calmanovici, C. & Karoumi, R. (2016). Structural Optimization of Concrete Slab Frame Bridges Considering Investment Cost. Journal of Civil Engineering and Architecture, 10, 982-994.
Open this publication in new window or tab >>Structural Optimization of Concrete Slab Frame Bridges Considering Investment Cost
2016 (English)In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, 982-994 p.Article in journal (Refereed) Published
Abstract [en]

The present study investigates computer-automated design and structural optimization of concrete slab frame bridges considering investment cost based on a complete 3D model. Thus, a computer code with several modules has been developed to produce parametric models of slab frame bridges. Design loads and load combinations are based on the Eurocode design standard and the Swedish design standard for bridges. The necessary reinforcement diagrams to satisfy the ultimate and serviceability limit states, including fatigue checks for the whole bridge, are calculated according to the aforementioned standards. Optimization techniques based on the genetic algorithm and the pattern search method are applied. A case study is presented to highlight the efficiency of the applied optimization algorithms. This methodology has been applied in the design process for the time-effective, material-efficient, and optimal design of concrete slab frame bridges

Place, publisher, year, edition, pages
David Publishing Company, 2016
Keyword
Slab frame bridge, structural design, structural optimization, genetic algorithm, pattern search method
National Category
Infrastructure Engineering
Research subject
Civil and Architectural Engineering
Identifiers
urn:nbn:se:kth:diva-202946 (URN)10.17265/1934-7359/2016.09.002 (DOI)
Note

QC 20170314

Available from: 2017-03-08 Created: 2017-03-08 Last updated: 2017-11-29Bibliographically approved
Safi, M., Du, G., Simonsson, P. & Karoumi, R. (2016). Sustainable bridge infrastructure procurement. In: IABSE Congress Stockholm, 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment. Paper presented at 19th IABSE Congress Stockholm 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, 21 September 2016 through 23 September 2016 (pp. 724-731). International Association for Bridge and Structural Engineering (IABSE).
Open this publication in new window or tab >>Sustainable bridge infrastructure procurement
2016 (English)In: 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, 724-731 p.Conference paper (Refereed)
Abstract [en]

The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a practical holistic approach that agencies could use to procure the most "sustainable" (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering the main bridge lifecycle aspects: life-cycle cost, service life-span, aesthetic demands and environmental impacts.

Place, publisher, year, edition, pages
International Association for Bridge and Structural Engineering (IABSE), 2016
Keyword
Aesthetic, Bridge, Design-build contract, Infrastructure, LCA, LCC, Life cycle assessment, Life cycle cost, Sustainable, Environmental impact, Investments, Life cycle, Model buildings, Service life, Sustainable development, Design-build contracts, Life Cycle Assessment (LCA), Lifecycle costs, Bridges
Identifiers
urn:nbn:se:kth:diva-216846 (URN)2-s2.0-85018948026 (Scopus ID)9783857481444 (ISBN)
Conference
19th IABSE Congress Stockholm 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, 21 September 2016 through 23 September 2016
Note

Conference code: 127207; Export Date: 24 October 2017; Conference Paper; Correspondence Address: Safi, M.; FOLKBRO and ÅF ABSweden; email: mohammed.safi@folkbro.com. QC 20171128

Available from: 2017-11-28 Created: 2017-11-28 Last updated: 2017-11-28Bibliographically approved
Cantero, D., Ülker-Kaustell, M. & Karoumi, R. (2016). Time-frequency analysis of railway bridge response in forced vibration. Mechanical systems and signal processing, 76-77, 518-530.
Open this publication in new window or tab >>Time-frequency analysis of railway bridge response in forced vibration
2016 (English)In: Mechanical systems and signal processing, ISSN 0888-3270, E-ISSN 1096-1216, Vol. 76-77, 518-530 p.Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
Academic Press, 2016
Keyword
Bridge, Dynamics, Forced vibration, Railway, Vehicle, Wavelet, Bridges, Frequency domain analysis, Railroads, Vehicles, Vibrations (mechanical), Wavelet transforms, Continuous Wavelet Transform, Energy distributions, Nonlinear behaviours, Time frequency analysis, Time frequency domain, Vibration analysis
National Category
Civil Engineering
Identifiers
urn:nbn:se:kth:diva-186903 (URN)10.1016/j.ymssp.2016.01.016 (DOI)000374812200032 ()2-s2.0-84957922879 (Scopus ID)
Funder
EU, FP7, Seventh Framework Programme, IAPP-GA-2011-286276
Note

QC 20160516

Available from: 2016-05-16 Created: 2016-05-16 Last updated: 2017-11-30Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-5447-2068

Search in DiVA

Show all publications