INSPIRE foresees synergies of three different layers with complementary and overlapping functionalities aimed at protecting the structures from ground and airborne excitations.
Design and demonstration of novel meta-material concepts for wave mitigation in soil. The first layer (“Meta-Soil”) foresees measures for treating the soil which circumscribes the structures, rendering the structures fully or partially isolated from the effect of the incident ground waves from all directions. “Meta-Soil” includes a spectrum of wave mitigation measures based on extended meta-material concepts, such as cloaks or properly designed pile arrays/”artificial forests”, which enable diversion of seismic and other low frequency waves, or advanced energy dissipation mechanisms, such as “rainbow traps”. The research work is divided in 5 individual research tasks as follows:
ESR01 – Design of classes of mechanisms to be inserted into foundation piles. The envisaged mechanisms may include energy absorbing-dissipating microstructures based on properly stressed tensegrity elestomer structures, appropriate negative stiffness “anti-springs” and multi-resonant cellular cores, as well as liquid dissipating media.
ESR02 –ESR03 – Development of configurable pile arrays for the efficient protection of buildings against low-frequency ground-induced vibration and the effects of seismically induced Rayleigh waves.
ESR04 – In depth investigation of geometric transforms in order to make research advances in the design of seismic cloaks.
ESR05 – Numerical and Experimental Demonstration of a urban scale soil-foundation-structure scheme integrating a spectrum of meta-soil concepts to provide seismic protection at a community level. ESR01 to ESR04 will support and participate in this activity and will provide results and samples of their individual designs to be tested.
This layer applies and demonstrates novel meta-material and other related absorber concepts or the design of foundations and support systems to protect structures against broad-band excitation in all three spatial directions. The research work is divided in 4 individual research tasks as follows:
ESR06 – Conceptual design of micro-structured materials based on elements subject to frictional forces and capable of self-oscillating under a steady-state input.
ESR07 – Analysis of non-linear physical mechanisms, based on unstable dynamic potentials, which lead to “negative stiffness forces”. Applications to the protection of monuments and high-rise slender structures.
ESR08 – Conceptual Design and development of seismic isolation bearings for structures and large assets based on additively manufactured elastomer/steel pentamode materials confined between steel stiffening plates.
ESR09 – Conceptual design and development of seismic and low-frequency protection devices exploiting the 3D ‘negative stiffness’ concept.
This final layer includes novel integrated design concepts for innovative high impact applications. The following 6 applications are foreseen:
ESR10 – Develop a modular, broad-band 3D approach (“META-PIPES”) for the protection of piping systems and associated structures from all sources of seismic and other related hazards and excitations
ESR11 – Conceptual design of an artificial material – “META-GRAVEL” designed to present desirable broadband properties in 3D and low-frequency attenuation. Its primary application is to provide a layer able to protect long and distributed structures (e.g. underground pipes, tunnels, building foundations, irrigation-channels, rails, roads/”meta-asphalt’, etc) from earthquakes and strong shocks and blasts.
ESR12 – Development of novel pier foundation concepts for the seismic protection for bridges. The latter will enable the functions of conventional seismic isolators while permitting controlled rocking motion at the base of a bridge pier.
ESR13 – Integration of different meta-material concepts towards the development of a novel rail/sleeper/ballast concept that will allow advanced wave inhibition measures along the rail. These may include the implementation of locally resonant meta-materials inside the sleepers in combination with granular metamaterials (e.g. “dark breathers”).
ESR14 – Development of new-generation acoustic barriers using arrays of appropriate pillar designs based on appropriate phononic disordered concepts.
ESR15 – Development of low-cost acoustic panels (for applications to floors or ceiling) with enhanced performance in the low frequency range.