Enhancing Seismic Performance of Bridges with a Novel Friction Tension Only Brace (FTOB)
摘要
As the demand for robust seismic protection in bridge design grows, traditional approaches like ductile seismic design and seismic isolation design are encountering limitations concerning nonlinear deformation and residual displacement. To address these challenges, various low-damage seismic devices have emerged, with low damage braces being widely acknowledged and utilized within the engineering community. Their appeal stems from their strong bearing capacity, well-defined force path, and straight forward replacement process. However, these devices still face challenges related to premature buckling, slacking, or high residual displacement. This paper introduces a novel solution in the form of the friction tension-only brace (FTOB), aimed at mitigating the drawbacks of existing seismic devices during earthquakes while maintaining the overall structure in a low-damage state. The paper begins by elucidating the operational mechanism of the FTOB. Subsequently, it presents a hysteretic model for the FTOB based on analytical principles and elaborates on its behavior. The accuracy of the proposed hysteretic model is then validated against Finite Element Analysis (FEA) numerical results. Finally, the seismic performance of double-column piers is evaluated through nonlinear seismic time-history analysis. The findings reveal that the double diagonal arrangement of FTOB yields the most favorable seismic outcomes, significantly reducing the maximum bending moment, maximum shear force, and maximum displacement by 67%, 67%, and 66%, respectively.