Gunnstein Thomas Frøseth
Background and activities
Estimating Remaining Service Life of Steel Railway Bridges
The Norwegian railway was mainly built in the period between 1850 and 1964 and consists of over 2700 bridges. About 1000 of these bridges are steel structures and common for all these bridges are that they were not designed for the current axle loads and train speeds. In addition, the fatigue limit state was typically not considered in design of structures during this period. Although effort has been put in to meet the immediate demands and to ensure safe operation, questions regarding the current state and remaining service life of these bridges have risen. Being able to accurately predict the state of these bridges is essential to manage the railway infrastructure as efficient as possible in respect to economic, social and environmental requirements.
Field measurements are the most precise way of assessing the state of bridges, but due to the sheer amount of bridges it is not feasible to conduct these investigations on the bridge stock. Numerical simulations are efficient tools which can be utilized to predict structural response, but the precision is dependent on the model complexity and uncertainties of input parameters. Combining field measurements with numerical simulations provides the best of both worlds and are necessary to obtain precise and complete state estimation of the bridge stock.
Main Objectives
- Improve prediction of remaining service life of steel railway bridges
- Quantify model error in finite element analysis of railway bridges
- Determine current and historic load conditions in the norwegian railway network
- Apply and improve model updating techniques for railway bridge simulations by field measurements.
Research Group
Supervisors
Scientific, academic and artistic work
A selection of recent journal publications, artistic productions, books, including book and report excerpts. See all publications in the database
Journal publications
- (2020) Operational Displacement Estimations of Railway Catenary Systems by Photogrammetry and the Integration of Acceleration Time Series. The international Journal of railway technology.
- (2020) A robust line-tracking photogrammetry method for uplift measurements of railway catenary systems in noisy backgrounds. Mechanical systems and signal processing. vol. 144.
- (2020) Damage Detection Applied to a Full-Scale Steel Bridge Using Temporal Momens. Shock and Vibration. vol. 2020.
- (2020) HOW CONSERVATIVE IS THE NORWEGIAN FATIGUE LOAD MODEL FOR SERVICE LIFE ESTIMATION OF RAILWAY BRIDGES?. Proceedings of the International Conference on Structural Dynamic , EURODYN.
- (2019) Evolution of load conditions in the Norwegian railway network and imprecision of historic railway load data. Structure and Infrastructure Engineering. vol. 15 (2).
- (2019) Finding the train composition causing greatest fatigue damage in railway bridges by Late Acceptance Hill Climbing. Engineering structures. vol. 196.
- (2019) Load model of historic traffic for fatigue life estimation of Norwegian railway bridges. Engineering structures. vol. 200.
- (2017) Influence line extraction by deconvolution in the frequency domain. Computers & structures. vol. 189.
- (2016) Operational modal analysis and model updating of Riveted steel bridge. Conference Proceedings of the Society for Experimental Mechanics Series. vol. 2.
Part of book/report
- (2020) Design of a monitoring system for a long-span suspension bridge: optimal sensor placement. EURODYN 2020: Proceedings of the XI International Conference on Structural Dynamics.
- (2018) Damage detection of steel bridge by numerical simulations and measurements. Life-Cycle Analysis and Assessment in Civil Engineering.
- (2018) Inspection of steel bridges by modal hammer from bridge deck only. Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges.
- (2016) Close Range Photogrammetry for Measuring the Response of a Railway Catenary System. PROCEEDINGS OF THE THIRD INTERNATIONAL CONFERENCE ON RAILWAY TECHNOLOGY: RESEARCH, DEVELOPMENT AND MAINTENANCE.
- (2015) System Reliability Analysis of Steel Railway Bridge Based on Historic Rolling Stock Records. Proceedings of The 13th Nordic Steel Construction Conference (NSCC-2015).