Bridges are fundamental elements of our infrastructure system, indispensable for the effective movement of people and goods in territories with varied orography and often high seismic, hydraulic and geomorphological risk. The natural degradation of materials, accelerated by the aggressive environmental conditions, inefficient maintenance and construction flaws are reasons why the current infrastructural heritage requires a great deal of attention in order to identify the most critical situations and prevent the occurrence of adverse events. This proposal has drawn inspiration from recent field experiences in order to select protection, management, and maintenance measures that have immediate applications to real emergency situations. In particular, it is focused on the river flow dynamics, which plays an important role in riverbed morphology. Building a bridge pier along the river alters its cross-section, causing a change in the water flow. These changes are mainly responsible for pier scour that represents the main cause of bridge failures. We propose the application of an innovative device that will act as an intensity damper of the vorticity generated by the complex dynamics occurring at the intersection between the bottom of the channel and the obstacle. BIO-EMBRACE aims at analyzing the flow dynamics at different flow regimes and the boundary conditions between the water flow and the bridge pier, through a novel, hybrid, multiscale approach. The final deliverable of the project will be the design and testing of an innovative device able to eventually reduce scour. We will develop an integrated theoretical-numerical-experimental methodology merging the experience of the partners in their areas of expertise, namely the fluid dynamics simulation and the experimental techniques. The numerical simulations will be conducted both through traditional Computational Fluid Dynamics (CFD), and two particle based numerical methods, the Lattice Boltzmann Method (LBM) and the Smoothed Particle Hydrodynamics (SPH), given the expertise in this field of all the operating units involved. The numerical simulations, appropriately validated, will support the definition of models, which could be easily applied for design purposes.
The innovation of the project is related to the need to fill these gaps, addressing all three issues together, making them inseparably linked. As a further, important outcome of the project, there will be the patenting and possible commercialization of the novel, bio-inspired bridgelet devices to be installed as a retrofit countermeasure for existing piers. The commercialization of such novel devices will deeply impact on the overall safety and maintenance sector, allowing to boost the performance of the present Disaster Risk Management facilities and promoting novel and safer standards for the engineering design and realization of new bridges. Such new design paradigm besides promoting the safety, will also open the path towards the realization of structures easier to be monitored, with the capability of harvesting energy directly from the water flow, an emerging field in the technological research. This opportunity could revolutionize the approach to renewable energy and energy conservation, allowing to directly obtain usable energy from a massive, but unexploited source. The project will also provide new answers to the compelling problem of sustainable and clean energy generation, without impacting the natural resources. In conclusion this project is characterized by a huge scientific and socio-economic impact, in different fields ranging from the hydraulic safety of existing piers, to the development of novel standards for the bridge design and maintenance.
One of the most interesting aspects of BIO-EMBRACE lies in the bio-inspiration of the countermeasures that will be devised: the design of the proposed device derives from nature and more specifically from the particular deep-sea, glass sponge Euplectella aspergillum, whose remarkable structural and fluid dynamic performance have inspired several important works in the scientific literature. It is worth underlining that the research units involved in the present project have already successfully collaborated in the past, as highlighted by the several publications in co-authorship reported in the CV of the scientists involved. Moreover, most of the people involved have already applied their field of expertise to fluid-structure problems.
The aim of our proposal is to provide a comprehensive and relevant analysis of the flow evolution upstream and around the bridge pile and to combine numerical and experimental simulations to test the capability of a bio-inspired indirect method device to reduce the erosive effects of the “horseshoe vortex” under different flow regimes. The proposed innovation would drastically improve the maintenance procedures of bridge piers augmenting the life expectation span of its foundations. Furthermore, given the massive presence on the Italian territory of many small rivers and water courses interested by old bridges and man-made structures, the idea behind the proposal is to design a device able to be retro-fittable and applicable to existing piers without modifying their structure. These two aspects not only have a major implication in the sector of environmental resilience and disaster risk management (areas of proven expertise of the leader partner UNISTRAPG and the P.I.), but indicate a peculiar congruence with the strategic topic and the selected cluster. BIO-EMBRACE draws its inspiration from the threat represented by the scouring phenomena at the pier-riverbed junction, in order to propose a groundbreaking, fully-innovative bio-inspired countermeausure, based on the skeletal motifs of the deep-sea glass sponge E. aspergillum, which has recently shown remarkable fluid dynamic performance,[Falcucci1]. The presence of the horseshoe vortex frets the riverbed, leading to the creation of scour and consequently increasing the intensity of the erosive phenomenon, with possible catastrophic outcomes. Thus, besides proposing solutions that are a scientific breakthrough per-se, the success of BIO-EMBRACE will have a remarkable societal impact, through the release of data and instruments for the evaluation of the potential risks related to the scouring in existing bridges. Thus, the original idea of BIO-EMBRACE is to reach different ambitious goals by focusing the research on 5 specific objectives: Assessment and mapping of scouring vulnerability for existing bridge; Development of a novel, hybrid, validated HPC platform for complex, free-surface dynamics simulation; Experimental campaign on real-world cases; Design and Development of a real-scale innovative retrofittable device; Patent proposal application and dissemination.
The project impact is broad from several points of view. The first important impact is expected in the area of risk assessment concerning bridge vulnerability. Italy is a territory full of large-, medium- and small-scale rivers, with many of them crossing man-made artifacts, sometimes even of historical importance. Through BIO-EMBRACE, unified guidelines to better assess the risk related to different flow regimes with respect to the characteristics and condition of the obstacle structure will be delivered, with the risk matrix as an OpenAccess tool for Public Institutions and private companies. Such an instrument will hugely impact the readiness of a territory to promptly react to disastrous events, hence delivering important economic, but above all, societal benefits. From a scientific point of view, the novel, hybrid methodology “massively” scalable for HPC, real-world case studies will provide a breakthrough “per-se", with potential, broad fall-outs even in different fields from that under investigation: free-surface and multiphase flows, in general, are in fact ubiquitous and their applications are uncountable. Similar, huge repercussion will be achieved by the results of the experimental campaign, that will prompt a huge, OpenAccess dataset, that will turn of great utility for both Public Institutions and private companies. On top of that, the possibility to make direct comparison of the novel, hybrid methodology with the experimental results will allow to also set a new scientific and technological paradigm for the new engineering standards in this field. To date, an integrated methodology for the reliable analysis of free-surface fluid-structure interaction is missing. This is due to the scarcity of experimental data, to the lack of numerical models of fluid-structure interaction at the same time accurate and with acceptable computational costs and to the absence of reliable theoretical models to be used in the design phase.
Chiara Biscarini - Università per Stranieri di Perugia
Valentino Santucci - Università per Stranieri di Perugia
Giacomo Falcucci - Università degli Studi di ROMA "Tor Vergata"
Andrea Colagrossi - Consiglio Nazionale delle Ricerche
Salvatore Marrone - Consiglio Nazionale delle Ricerche