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Abstract: In this study, we investigate the load-bearing capacity of pre-stressed concrete girders under various damage levels. We employed Distributed Acoustic Sensing (DAS) technology to monitor and quantify changes in the girder response as damage levels were incrementally introduced. This approach enabled the real-time measurement of dynamic behavior over the entire length of the girder, allowing for a detailed characterization of damage-induced structural changes. To complement the DASbased approach, we also applied classical acceleration-based damage detection techniques. By integrating these methods, we aimed to cross-validate the results and provide a more comprehensive understanding of damage progression and its impact on structural performance. The experimental campaign, conducted in Ljubljana, ZAG, involved full-scale testing of pre-stressed concrete girders subjected to controlled damage scenarios. This setup ensured a realistic assessment of the girders’ residual capacity and failure mechanisms. The paper presents preliminary results from this experimental study, emphasizing the capability of DAS measurements to detect and characterize damage, while also comparing its performance against traditional methods. By combining advanced sensing technologies with established techniques, this research highlights the potential of DAS as a transformative tool in structural health monitoring.
Keywords: distributed acoustic sensing, distributed fiber optic sensing, structural health monitoring, frequency analysis, load test, infrastructure monitoring, bridge monitoring
Published in DiRROS: 22.01.2026; Views: 219; Downloads: 127
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Abstract: Scour erosion continues to cause significant issues for the stability and lifespan of bridges worldwide. In Slovenia, extreme flooding in 2023 caused the collapse or failure of many bridges, primarily due to scour, which was exacerbated by debris accumulation. Despite advances in predicting and monitoring scour, it remains among the top reasons for the failure of bridges during flooding. Recent advances in vibration-based health monitoring suggest that scour erosion can be detected using methods such as changes in natural frequency, mode shapes, flexibility-based deflection, and other approaches using offline sensors such as passing vehicle responses. Many of these methods have been trialled numerically where scour is implemented as a reduction in the soil level (or stiffness) around a given bridge foundation. The most common way to model scour is to lower the soil level around a foundation, however, this ignores any contribution that the scour hole shape makes to the stiffness and strength of the soil beneath the scour hole. This paper investigates how the shape of scour holes influences the stiffness and strength of the remaining soil to understand the impact on the modal behaviour of a bridge. A numerical model of a bridge is developed where scour is implemented by removing Winkler springs from the model, and different scour hole shapes are considered in terms of how the remaining overburden influences the stiffness and strength of the soil springs. Scour hole shape properties are considered by means of varying the depth, width, and slope angle of the hole around a given foundation element. For the analyses in this paper, different scour hole shapes are implemented on an example bridge corresponding to local scour holes with narrow width; wider local scour holes; and general scour, where the full soil layer is removed (infinite width). The changes in the modal periods and mode shapes of the bridge in the traffic and river flow directions are assessed to understand the impact of the different scour types on the vibration characteristics.
Keywords: scour, dynamics, overburden, frequency, damage, bridges, scour hole shape
Published in DiRROS: 13.01.2026; Views: 145; Downloads: 102
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Abstract: Transportation infrastructure demands reliable, cost-effective, environmentally friendly, and safe solutions. It is, therefore, crucial to leverage both the knowledge gained from current practices and the potential offered by emerging technologies. This paper uses the scoring system approached in the INFRACOMS project to offer a framework for asset managers and technology providers to identify areas of improvement and make informed decisions regarding selecting and implementing remote condition monitoring solutions. We focus on two technologies for bridges, like bridge weigh-in-motion and digital inspection and centre around four areas: data analysis, visualisation and integration and potential for practical decision-making. Technologies are evaluated based on their intended use, acknowledging that some may have multiple applications due to novel sensor installations or data interpretation/visualisation methods. Consequently, a technology may undergo multiple appraisals within this system. We showcase the benefits of the scoring system, alignment with specific use cases, and potential for broad applicability.
Keywords: bridge, remote monitoring, scoring system
Published in DiRROS: 14.08.2024; Views: 1168; Downloads: 614
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Abstract: Paper presents selected results of the diagnostic load testing of a newly-built footbridge in Novo Mesto, Slovenia. The bridge is significant as the first bridge in Slovenia being built with the stress ribbon technology. The diagnostic load testing took place in March 2023 and comprised of three-stage static load testing, dynamic testing with a light truck driving over artificial obstacles, and measurement of ambient vibrations. The consistency between the actual response of the bridge and the response of the finite element (FE) model, used in the design, was evaluated by comparing vertical displacements from the static load testing, natural frequencies and mode shapes. The comparison of the results indicates a satisfactory agreement between the measurements and the response of the FE model, confirming the appropriateness of the employed FE model.
Keywords: bridge, bridge response measurements, stress ribon, load test
Published in DiRROS: 14.08.2024; Views: 1040; Downloads: 663
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Abstract: The paper presents a risk assessment model, developed in the project oVER-FLOw and further implemented in the project CROSScade, for determining the direct and indirect impacts of flooding hazards. As a consequence of flooding, transport infrastructure and flood protection systems can be significantly damaged and cause cascading effects on other infrastructure. To achieve flood resilient infrastructure, it is necessary to assess the vulnerability of critical assets in the affected area. The model uses novel vulnerability assessment methods for embankments and bridges exposed to different flood hazard scenarios allowing the asset owners to understand risk and performance of their infrastructure. Scarce financial resources are allocated on the critical assets allowing significant cost savings and avoiding the waste of non-renewable resources in strengthening large sections which have sufficient resilience. The consequence analysis is based on an improved quantification model for direct and indirect impacts of different flood hazard scenarios used for risk mapping of the affected area.
Keywords: flooding, risk assessment, critical infrastructure, economic loss
Published in DiRROS: 23.05.2024; Views: 1311; Downloads: 748
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