ON THE SOLITARY WAVE DYNAMICS OF TENSEGRITY LATTICES WITH STIFFENING RESPONSE: A NUMERICAL STUDY AndreaMicheletti 1 , GiuseppeRuscica 2 , AdaAmendola 3 , IdaMascolo 3 , FernandoFraternali 3 1 Department of Civil and Computer Science Engineering, University of Rome Tor Vergata, Italy e-mail: micheletti@ing.uniroma2.it 2 Department of Engineering and Applied Sciences, University of Bergamo, Italy e-mail: giuseppe.ruscica@unibg.it 3 Department of Civil Engineering, University of Salerno, Italy e-mail: {adamendola1,imascolo,f.fraternali}@unisa.it Keywords: Tensegrity lattices, Stiffening behavior, Solitary waves, Compactons, Acoustic metamaterials. Abstract. We present some peculiar results about the solitary-wave dynamics of novel tensegrity- based metamaterials. It has been previously shown that one-dimensional chains of triangu- lar tensegrity prisms with stiffening behavior support the propagation of compressive solitary waves. We show that such result can be generalized to two-dimensional and three-dimensional modular tensegrity lattices composed of polygonal and polyhedral units. Differently from the one-dimensional case, the stiffening response of these lattices originates at the interface be- tween adjacent units, not from the unit themselves. We present numerical results on the response to impulsive loads of slender assemblies composed by square units in two-dimensions, and cu- bic units in three-dimensions. We observed compact compressive waves forming at impact locations, together with localized thermalization effects. Such compact waves propagate with nearly constant speed and energy, while maintaining their shape, and emerge from collision with other compact waves almost unaltered, losing a small fraction of their energy. These re- sults suggest the investigation of the dynamics of regular and quasi-regular tessellations formed by other types of polygonal and polyhedral units. 1563 COMPDYN 2019 7 th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, M. Fragiadakis (eds.) Crete, Greece, 24–26 June 2019 Available online at www.eccomasproceedia.org Eccomas Proceedia COMPDYN (2019) 1563-1570 ISSN:2623-3347 © 2019 The Authors. Published by Eccomas Proceedia. Peer-review under responsibility of the organizing committee of COMPDYN 2019. doi: 10.7712/120119.7019.18382