Seismic performance of gear-transmission friction rocking wall system, and its relevant restoring force model

Hybrid rocking walls have superior anti-seismic redundancy and robustness, which have broad application prospects. Traditional hybrid rocking walls use mild steel or external dampers to dissipate energy, which do not release the horizontal rocking displacement of the wall and can easily cause damage to the dampers, wall, and the connections between them. In view of these, this study proposed a gear-transmission friction rocking wall system (GTFD-RW). Subsequently, the 3D finite element models of GTFD-RWs were established and validated against existing experimental results. On this basis, parametric analysis of the seismic performance of GTFD-RWs was performed, including the axial compression ratio, prestressing tendon position, shear span ratio, and damping force of GTFD. And the realization of design concept of GTFD-RWs was discussed. Finally, a restoring force model for GTFD-RWs was proposed and verified. The results indicate that the GTFD can release the horizontal rocking displacement of GTFD-RWs, and effectively reduce the wall damage. The increase of axial compression ratio n will increase the wall damage and an appropriate n range (around 0.10) can better balance the self-centering ability and damage degree of GTFD-RWs. The increase of position of prestressing tendons d/b0 (within the range of 0.18–0.32) and decrease of shear span ratio h/b0 (not exceed 2.80) can significantly improve the self-centering performance of GTFD-RWs. And the increasing of damping force Fd can significantly improve the energy dissipation capacity and bearing capacity of GTFD-RWs, while increase the local damage to the walls and reduce their relevant self-centering capacities. Thus, the damping force of GTFD is suggested to be less than 90 % of the equivalent yield force of the pure wall. Additionally, the proposed methods can accurately describe the seismic performance and resilience characteristics of GTFD-RWs (error within ±15 %), and can be referred in the design of novelty GTFD-RWs. •A novelty gear-transmission friction rocking wall system (GTFD-RWs) was proposed.•Parametric study on the seismic performance of GTFD-RWs was conducted.•A theoretical restoring force model of GTFD-RWs was proposed and evaluated.