BEHAVIOR EXPERIMENT AND CAPACITY EVALUATION OF RESILIENT EXTERIOR SHEAR KEY OF BRIDGES

In the aseismic design of bridges, shear keys should not only restrict the superstructure transverse displacement to prevent from unseating, but also void transferring the excessive seismic force to piles. Therefore, shear keys are commonly designed as sacrifice members. Based on a kind of novel resilient bridge exterior shear keys, four shear key specimens were designed in accordance with current Chinese aseismic design guidelines of highway bridges and tested under monotonic transverse loading. The damage modes, failure models and mechanical mechanisms were illustrated. Parametric study was carried out on a longitudinal reinforcement ratio. Calculation formulas were developed to predict the capacities of shear key specimens. Compared with the experimental results, the calculation formulas can reliably evaluate the capacities of shear key specimens. It can be concluded that this kind of resilient exterior shear keys have excellent displacement capacity, and can reduce the damage to cap beams and abutments. In addition, they are easy to be repaired and replaced, and especially suitable for performance-based aseismic design of bridges.