Modeling seismic behavior of precast segmental UHPC bridge columns in a simplified method

Abstract

The paper aims to provide a simplified method for modeling seismic performance of precast segmental UHPC bridge columns based on the identified flap-shaped hysteretic model (IFSHM), of which four key parameters, including the elastic stiffness, the yield lateral force, the post-yield stiffness ratio, and the energy dissipation coefficient, are calculated with design parameters in the simplified method. Theoretical and parametric analyses were conducted to build the relationships among the four key parameters and two characteristic states, including the yield and ultimate states. The simplified method was established by respectively deducting the calculation procedures to determine the yield and ultimate states. Applying the simplified method to determine the four parameters of the IFSHM was validated by the reported cyclic loading test including three 1/3-scale specimens in literature. A proposed finite element model in previous research was used to check the feasibility of using the simplified method to predict nonlinear dynamic responses. Results show that the ultimate state is a suitable calculation state to determine the energy dissipation coefficient. The simplified method has the capacity of calculating the four parameters of the IFSHM. The simplified method can predict nonlinear static responses, including lateral force-drift ratio skeleton curve and energy dissipation per cycle. The determined IFSHM with the simplified method can be used to estimate nonlinear dynamic responses, including the maximum drift ratio and cumulative energy dissipation, when precast segmental UHPC bridge columns are subject to strong earthquake motions.