On the seismic protection of existing structures: a large-scale modelling of nonlinear soil-structure-TMD interaction

Design of Tuned Mass Dampers (TMDs) is a very debated topic, with wide literature exploring different strategies for optimal tuning of such devices to mitigate earthquake-induced structural vibration. Notwithstanding, the interaction with the foundation soils can significantly alter the dynamic response of the structural system, reducing the effectiveness of the anti-seismic device, as demonstrated by far for conventional absorbers only. In this study, an advanced numerical investigation on the seismic performance of a coupled soil-structure-TMD system is presented, referring to a non-conventional, large mass ratio TMD (LM-TMD) applied to a real case study. The computation procedure was implemented in OpenSees, allowing for an accurate description of the nonlinear behaviour of both the structural members and the soil. The LM-TMD consists in a superelevation of the existing structure, connected to the latter through a combination of bearing devices providing the desired dynamic coupling...