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Herein, novel graphene‐reinforced elastomeric isolators (GREI) are proposed. Elastomeric isolators (EIs) are special devices used for seismic isolation of structures. They are made of alternate layers of steel and rubber (steel‐reinforced EI [SREI]), and they position between the structure and its foundations to decouple them. The heavy weight and complex manufacturing process of SREI drives costs up, and this restricts their use to strategic buildings such as hospitals and civic centers. In recent years, alternative materials have been proposed to replace the steel sheets of SREI, e.g., glass or carbon fiber‐reinforced EIs (FREIs). However, their mechanical behavior requires further investigation before being implemented in existing and new structures safely. As a promising alternative, GREI is proposed here to overcome the heavy weight and long manufacturing process of SREI and the mechanical limitation of FREI to seismic excitations.

Herein, the mechanical behavior of a graphene‐recycled rubber compound is investigated by performing static and dynamic tests. Water‐based graphene suspension is deposited on recycled rubber pads via an electrostatic addition process. Results on tensile and compression tests indicate a significant improvement of the compound in strength and in damping. They also indicate that the compound experiences significant elongation (up to 500%) as well as withstands high tensile forces, 300% greater than the force that the recycled rubber mix would withstand. The effective compression modulus of the compound is also shown to increase by about 3.2 times at 10% strain with respect to the one for the recycled rubber mix. Results suggest that the graphene‐recycled rubber compound can deliver a sustainable solution for vibration mitigation applications.

This work is concerned with the bifurcational analysis of nonlinear dissipative systems affected by time delay. This issue typically arises when testing highly nonlinear energy dissipation devices, commonly used in vibration control of civil structures, and carried out experimentally via a hybrid technique known as Real-Time Dynamic Substructuring (RTDS) simulation. Unfortunately, the RTDS simulation is affected by time delay in the control feedback loop due to the actuator response, sensor reading and numerical processing. In essence, this paper focuses on studying the nonlinear dynamics induced by the interaction of a dynamical system with the nonlinear damper affected by the presence of time delay. Given the complexity of the system, numerical analysis is carried out in the context of bifurcational behavior, and bifurcation diagrams are computed using a continuation method. The bifurcational analysis presented here, provides a characterization of delay-induced nonlinear phenomena created by the interaction of the dynamical system with a delayed nonlinear response of the dissipation device. Nonlinear dynamics are also identified and characterized for different damper types when varying the damper model parameters, leading to the identification of system conditions at which the testing arrangement and test specimens can exhibit undesired dynamics.

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