Experimental Investigation and Local Reinforcement Strategy of Uplift‐Rocking Tall Double‐Column Bents Under Cyclic Loading

Rocking self‐centering (RSC) technology has emerged as a highly regarded solution for enhancing the seismic resilience of bridge systems by improving the self‐centering capability of bridges and mitigating the damage of main components. In order to facilitate this advanced technology to double‐column tall bents, which are critical infrastructure components in mountainous regions, an innovative uplift‐rocking double‐column bent (UR‐TDCB) system is proposed in the present study, and its cyclic performance is thoroughly investigated by means of a series of parametric experimental and numerical campaigns. Scaled UR‐TDCB specimens with an aspect ratio of 12.5, together with a monolithic counterpart, were designed in accordance with the design criteria and subsequently tested under quasi‐static cyclic loading. The test results showed that the alternating uplift‐rocking behavior limited both damage progression and residual deformation in main load‐bearing components (i.e., columns and link beams), achieving a 54%–87% reduction in the maximum curvature. However, this improvement is achieved at the expense of increased shear damage in beam‐column joints, which consequently limited the proportion of the rigid‐body rotation to merely 51% of the total deformation in the UR‐TDCB. Based on this crucial observation, an active local reinforcement strategy, achieved by enlarging the effective region of the joints was proposed, and comprehensively evaluated through numerical simulations. Moreover, the energy dissipation (ED) coefficient and the number of link beams, playing a decisive role in the hysteretic behavior of the system, were selected for a sensitive parametric analysis of UR‐TDCB with reinforced joints. Numerical results demonstrated the high efficiency of the proposed reinforcement strategy. Meanwhile, to achieve the expected flag‐shaped hysteretic response, the ED coefficient is recommended to range between 0.2 and 0.4, while the inclusion of link beams is essential for maintaining the intended uplift‐rocking mechanism.