The FUSAR project aims to improve the safety and efficiency of railway infrastructures by developing an advanced warning system based on the fusion of multi-scale and multi-source data. This innovative approach will enable proactive risk management, minimising service interruptions and environmental impacts, while reducing maintenance costs. The project combines IoT, LiDAR, GNSS, InSar and satellite imagery to effectively detect faults and risk areas. It also addresses challenges related to geo-referencing, data interoperability and automatic fault recognition. Using hybrid Deep Learning approaches, the project aims to establish a framework for data fusion at the decision-making level. The introduction of alert thresholds will help SNCF Réseau to anticipate faults and contribute to maintaining the availability of facilities.

Bitumen is a complex viscoelastic compound sensitive to its environment. Upon ageing on roads its viscosity increases and its chemical composition is significantly modified. As a consequence, the inclusion of old asphalts, strongly encouraged for sustainable development issues, has a detrimental impact on final mechanical properties of recycled asphalt materials. In order to technically support and promote this growing addition of aged pavements without decreasing the durability of the road structure, the choice of additives and neat bitumen is crucial because the good adequation of additives with old and new bitumen depends mainly on the nano-structure of the aged bitumen. Therefore, a focus on the nano-structural modification of bitumens in order to better understand the ageing mechanism and the subsequent loss of viscoelasticity is clearly needed. To address the objectives of the project, we propose new methodologies consisting in an extended investigation on aged and rejuvenated bitumen at the nanoscale, while no destructive sample preparation is needed, using Small-and Ultra Small-Angle X-Ray Diffusion (SAXS and USAXS) spectroscopies along with High Resolution Transmission Electron (HRTEM) and Atomic Force (AFM) microscopies. It is thus expected to characterize the multi-scaled aggregated structure of the colloidal asphaltene phase at the 0.2-1000nm scale in its bituminous matrix, and its evolution with: a) ageing, b) rejuvenating treatments and c) temperature at the fluid–viscoelastic transition. This nanoscale structure study will be correlated with data arising from methods basically used to characterise the macroscopic mechanical and chemical bitumen properties. To understand and to assess the impact of ageing on the bitumen nanostructure will help the stakeholders and industrial partners to better select their product in a sustainable development way (eco-conception) aimed at reducing the environmental impact of road construction.