A novel slip-friction connector for seismic applications in timber structures: analytical and experimental investigation

Slip-friction connectors are increasingly recognized as an effective strategy for enhancing the seismic performance of structures. Conventional solutions, however, commonly rely on bolt pretension to activate frictional resistance, which may lead to drawbacks such as preload losses over time, installation challenges, and concerns regarding long-term reliability. To overcome these limitations, this study proposes an innovative slip-friction connector that replaces bolt pretension with an elastic restoring force provided by a precompressed spring. The mechanical behavior of the proposed device is investigated through analytical modeling and experimental testing. An analytical solution is developed based on equilibrium equations, capturing the interaction between frictional sliding and elastic restoring effects in the force-displacement response. Cyclic tests are performed to validate the model and assess the energy dissipation capacity of the connector. Experimental results show excellent agreement with the analytical predictions, confirming the robustness of the proposed formulation. The findings of this study suggest that the proposed connector offers a promising solution for seismic applications in timber structures, with particular reference to cross-laminated timber (CLT) panels. In this context, the device may serve as an alternative to conventional connections, such as hold-downs, providing an efficient and tunable energy dissipation mechanism. The compact design, combined with the possibility of tailoring the mechanical response through spring stiffness adjustment, offers significant versatility for implementation in timber construction. Moreover, the simplicity of the analytical model ensures its practical applicability for design and engineering purposes.