The scouring process represents a significant contributing factor in the destabilising and destruction of civil structures (bridges, earth embankments and buildings) during major flood events, yet our understanding of the mechanisms involved remains highly empirical. The main objective of the SSHEAR project is to improve understanding of this scouring process through the use of innovative observation tools and physical and numerical hydraulic modelling, from laboratory to full-scale, for the purpose of optimising methods specific to diagnostics, advanced warning and general management procedures. This project is intended to create the conditions necessary for an expert opinion to emerge that compensates for, at a national level, a generally acknowledged lack of knowledge. In the case of the French railway network, a comprehensive inventory has been drawn up of infrastructure crossing or located adjacent to waterways. For over 30 years, improvements have continuously been introduced relative to monitoring policy and both the preventive and corrective maintenance of rail and road structures. The practical principles of such monitoring programmes are organised into different actions: periodic and detailed inspections of structures, risk analyses and diagnostics, enhanced surveillance based on the implementation of in situ instrumentation and/or investigation (including bathymetry surveys). However, despite these efforts, a sensitivity classification of structures to the problem of scouring has not been adequately addressed. To overcome this reliance on empiricism, while building general knowledge (especially at the national level) and proposing optimised methods aimed at diagnostics, advanced warning procedures and infrastructure management, SSHEAR sets forth a multi-scale and multi-scientific approach based on: - physical processes of flow and erosion in the vicinity of structures (e.g. bridges, dams, embankments, quay walls), - three laboratory experiments featuring multi-scale observation, - an innovative numerical approach built around a two-phase model, - observations and field recordings of actual structures subjected to hydro-sedimentary forcing imposed due to environmental or anthropogenic actions. The SSHEAR consortium comprises six Partners, whose complementarity offers a major asset to the project, namely: a specialist in soils and fluid mechanics with extensive field practice (Partner 1: Ifsttar); geotechnical and hydraulic engineers together with sedimentologists (Partner 2: Cerema); physicists and engineers focusing on complex systems (Partner 3: FAST); infrastructure management companies (Partner 4: Cofiroute, and Partner 5: SNCF); and a technological research institute, or IRT (Partner 6: Railenium). This combined set of diverse skills makes it possible to conduct a wide range of research on the scouring process and its consequences: - from feedback and measurements in the field to a multi-scale investigation of phenomena - from experimentation to numerical modelling - from fundamental science aspects to engineering aspects - from new knowledge acquisition to practical solutions implemented by end-users.

The quality of the air we breathe is a central concern of individuals living in urban and suburban areas. Millions of people are exposed every day to air pollution at high levels. The impact of such pollution on the human health is extremely alarming. Particularly, WHO and IARC have classified air pollution, including fine particles, as certain carcinogenic. Understanding the totality of exposures to air pollutants over the course of our daily life is a key concern to reduce the risk of some major diseases. However, the ability to acquire high-quality, relevant, and useful individual’s exposure data is challenging. Currently available air pollution fixed station networks allow to only account for background air pollution and less frequently proximity air pollution from road traffic. As a result, the measurements made through this kind of network typically provide the average exposure to air pollution in a specific geographical zone. In particular, they fall short to quantify the real individual’s exposure with respect to his/her indoor/outdoor daily life activities in different settings, such as transport, work, dwellings, etc. Nowadays, an increasing number of wearable and lightweight environmental sensors have emerged, enabling a continuum measurement of the real personal exposure anywhere at anytime. Such an evolution has been the main enabler of providing new solutions for data acquisition, namely community-based participatory sensing where citizens contribute data to the system with the purpose of sharing events of interest within the community. This technology has recently gained a great interest among the actors of environmental science in public, associative, and private sectors, while stimulating a wide range of research projects worldwide. Building on top of such a technology evolution, Polluscope aims at bringing together experts from environmental, metrology, epidemiological, and data sciences while providing methodologies, techniques, and tools – expected to drastically change the way individual’s exposure and exposure variability are measured, perceived, and evaluated. Such measurements will not only consider gaseous pollutants (Ozone, NO2), but also particulates (via particulate matter and black carbon) and those typical of indoor environments (VOC) – providing a representative overview of the air pollution. Gaining such enriched insights into individual’s exposure will contribute towards reducing individual risks of some diseases by changing their behavior. This will end up in a solid, invaluable, and vital societal impact namely, saving life and improving the individual well-being. To achieve these objectives, a novel infrastructure for real individual’s exposure data acquisition, processing, and analysis will be develope. For this to be done, several scientific and technical challenges come into the picture. The data are collected at a high frequency and might be massive and noisy. Therefore, the system must be able to process them efficiently, while taking into account both their velocity and their uncertainty. More importantly, it has to offer microenvironment and user’s activity recognition, through integration with external spatiotemporal resources. An efficient data collection and analysis will provide an insightful knowledge on individual’s exposure over his/her daily life activities, and will enable conducting analytical queries, novel risk assessment modeling, mining and comparing profiles of pollution exposures, and so on. Therefore, it is evident that a robust, efficient, and powerful data science technology is crucial. Lastly, Polluscope will be evaluated under real-world use cases. Several type of population will be targeted by the data acquisition campaign. Both diseased and healthy subjects will be involved to conduct an epidemiological study relating air pollution exposure to health on the one hand, and volunteer participants for the crowd sensing on the other hand.

In most cases, the deterioration of reinforced concrete structures is due to corrosion caused by aggressive agents from the external environment such as carbon dioxide and chloride ions. In order to control the lifetime of structures, efforts have to be made to manage the risk of corrosion from the structure design. This is of course an economic challenge since the maintenance of ageing concrete structures is nowadays more and more costly for owners. It is also an environmental challenge because, like other materials, the use of concrete has impacts at global scale (8% of the worldwide greenhouse gas emissions) or at local scale (natural aggregates consumption). In the current design standards, the control of structures lifetime is done through an obligation of means. For instance, the European standards require a minimum cover of reinforcement or a minimum binder content in the concrete composition. In the coming years, the performance-based approach will be introduced as a second way to design the concrete formulation. Concrete performances can be assessed through accelerated ageing tests or durability indicators. In France, application methods of the performance-based approach are available. A national project under construction (PERFDUB) shall gather most of construction actors to optimize these methods and use it in a global approach. To determine the threshold values of durability properties measured by tests, the performance-based approach need modeling tools which are able to predict the long-term behavior of reinforced concrete structures. The models will be used to quantify the durability indicators and to verify the reliability of the values. The objective of the project MODEVIE is to provide such models applicable by end-users in the frame of the performance-based approach. In recent years, many progresses have been done in the modeling of physical, chemical and mechanical phenomena acting on the durability of reinforced concrete. However, the existing models are often focused on only one of the stages of corrosion process, for instance on the stage of aggressive agents transfers or on the phase of corrosion propagation. The aims of MODEVIE is first to take into account all the different periods of the structure life in chaining behavior models, from transfers to corrosion and mechanical damage, and secondly to define a model adapted to the use of the performance-based approach in the normative context. MODEVIE will also provide a better understanding of parameters favorable to steel reinforcement depassivation and corrosion propagation. Limit states associated with reinforcement corrosion will be also rationally defined. Organized into six tasks, the project will involve modeling and experiments. The latter will take into account parameters such as concrete casting, aggregates nature and binder type. We will study concretes potentially qualified by the performance-based approach, i.e. concretes with high content of mineral addition or recycled aggregates. Finally, MODEVIE will lead to the definition of an “engineer” type model usable by end-users for the calculation of the structure lifetime for a given limit state (corresponding to an acceptable corrosion state). The entry parameters will be the concrete mix parameters, environmental conditions and materials data available from standard tests. MODEVIE gathers specialists partners in the fields of mass transfer, corrosion and normative context for the durability of concrete structures, which are all involved in the development of the performance-based approach for concrete structures: university laboratories (LaSIE, GeM, LMDC ), public laboratories (IFSTTAR, CEREMA) or private (LAFARGE, Eurovia, VINCI Construction France, CERIB).