DESTination RAIL – Decision Support Tool for Rail Infrastructure Managers Project Reference: 636285 H2020-MG 2014-2015 Innovations and Networks Executive Agency Project Duration: 1 May 2015–31 April 2018 Report on Assessment of Bridges Authors * Lorcan Connolly (ROD-IS), Luke Prendergast, Neda Mostafa, Richard Loendersloot *Corresponding author: Lorcan Connolly, [email protected] Date: Dissemination level: (PU, PP, RE, CO): PU This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 636285 D2.2 Report on Assessment of Bridges DESTination RAIL – Decision Support Tool for Rail Infrastructure Managers Table of Contents 1 Executive Summary ..................................................................................................................... 4 2 Introduction .................................................................................................................................... 5 2.1 Background ........................................................................................................................... 5 2.2 The Boyne Viaduct ............................................................................................................... 5 3 Structural Health Monitoring ....................................................................................................... 7 3.1 Finite Element Model ........................................................................................................... 7 3.2 Ultimate Limit State Assessment ....................................................................................... 8 3.3 Instrumentation and Data Collection ............................................................................... 14 4 Application of Measurement to ULS Assessment ................................................................. 18 4.1 Finite Element Calibration ................................................................................................. 18 4.2 Calculation of Dynamic Allowance .................................................................................. 22 4.3 Implications of SHM on safety assessment. .................................................................. 34 4.4 Direct Calculation of Reliability from Measurement ...................................................... 36 4.5 Conclusions ......................................................................................................................... 37 5 Deterioration ................................................................................................................................ 38 5.1 Steel Deterioration ............................................................................................................. 38 5.2 Rehabilitation Strategies ................................................................................................... 40 5.3 Conclusions ......................................................................................................................... 42 6 Probabilistic Fatigue Assessment ............................................................................................ 43 6.1 Probabilistic Assessment .................................................................................................. 43 6.2 Deterministic assessment ................................................................................................. 47 7 Damage Detection ..................................................................................................................... 49 7.1 Introduction .......................................................................................................................... 49 7.2 Existing Modal-based Damage Sensitive Features, DSFs .......................................... 50 7.3 A Novel Modal-based Approach for Damage Detection in Bridges ........................... 51 7.4 Conclusion ........................................................................................................................... 66 8 Soil-Structure Interaction ........................................................................................................... 67 8.1 Focus of Task ..................................................................................................................... 67 8.2 Winkler Model ..................................................................................................................... 67 8.3 Nonlinear Dynamic Modelling ........................................................................................... 70 8.4 Site Calibration ................................................................................................................... 74 9 Summary and Conclusions ....................................................................................................... 76 10 References .............................................................................................................................. 77 2 D2.2 Report on Assessment of Bridges DESTination RAIL – Decision Support Tool for Rail Infrastructure Managers Appendix A: Deterministic Assessment 1 Results ........................................................................ 81 Appendix B: Deterministic Assessment 2 Results ........................................................................ 85 Appendix C: ABAQUS FE model of the Boyne Viaduct ............................................................... 88 Appendix D: Mathematical model of the Boyne Viaduct .............................................................. 89 3 D2.2 Report on Assessment of Bridges DESTination RAIL – Decision Support Tool for Rail Infrastructure Managers 1 Executive Summary The aim of DESTination RAIL is to provide solutions for a number of problems faced by EU rail infrastructure managers. At present Infrastructure Managers make safety critical investment decisions based on poor data and an overreliance on visual assessment. As a consequence their estimates of risk are therefore highly questionable and large-scale failures are happening with increasingly regularity. As the European rail Infrastructure network ages, investment becomes more challenging. As a result reliability and safety are reduced, users’ perception of these is negative and the policy move to increased use of rail transport is unsuccessful. The objective of this project (safer, reliable and efficient rail infrastructure) will be achieved through a holistic management tool based on the FACT (Find, Analyse, Classify, Treat) principle. This deliverable details the results of Task 2.3 of the project – Assessment of structures. An SHM strategy was devised for the bridge on the basis of an FE model, deterministic assessment and probabilistic assessment. The SHM data has been used to inform a much more accurate ULS probabilistic assessment, which indicated higher levels of safety that that which was calculated previously. The effect of deterioration on the reliability was probabilistically modelled in accordance with DESTination Rail Deliverable 2.1. A probabilistic Fatigue assessment has also been exemplified based on both measurement and model-based assessment. A novel modal-based approach for damage detection in Bridges has been introduced with the monitoring data. Finally, advanced soil-structure interaction techniques have been developed an are discussed in the final section of this report. Each task from the DESTination Rail grant agreement has been achieved with one minor exception. Data from a demonstration project at the Boyne Valley bridge on the Irish Rail Network was originally intended to be used to calibrate the soil structure interaction methodology. This has turned out not to be possible, as the bridge in question is actually founded on rock, thus there is no soil-structure interaction specifically. Thus, the soil structure interaction methodology developed in this Deliverable was calibrated by correlations to Cone Penetration Test (CPT) data from another site. 4 D2.2 Report on Assessment of Bridges DESTination RAIL – Decision Support Tool for Rail Infrastructure Managers 2 Introduction 2.1 Background The aim of DESTination RAIL is to provide solutions for a number of problems faced by EU rail infrastructure managers. The objective of this project (safer, reliable and efficient rail infrastructure) will be achieved through a holistic management tool based on the FACT (Find, Analyse, Classify, Treat) principle. This deliverable is part of the Analyse work package and details Task 2.2 of the project – Assessment of structures. A case-study bridge, the Boyne viaduct located in Drogheda, County Louth, Ireland, will be used to exemplify the algorithms developed in application of the algorithms developed in Tasks 2.1 and 2.2 of the project. 2.2 The Boyne Viaduct The Boyne viaduct, as it exists today, was constructed in the early 1930s and consists of fifteen semi-circular masonry arch spans and three simply supported steel-girder spans. This assessment only considered the central steel-girder span. Figure 1 shows a view of the steel superstructure of the Boyne viaduct. Figure 1 – Aerial view of the Boyne Viaduct superstructure 5 D2.2 Report on Assessment of Bridges DESTination RAIL – Decision Support Tool for Rail Infrastructure Managers The central span is approximately 81m and consists of a truss with 10 bays. The top chord has a curved profile and the maximum distance from the bottom chord to the top chord is approximately 10.6m. The