Seismic Energy Dissipation in Bridges for Performance Enhancement

Modern performance-based bridge design seeks to control damage in specific failure modes in order to balance safety and economy, particularly in high-seismic regions where inelastic and ductile deformation is expected to occur, both in the structure and soil, allowing potential reduction in seismic demand through fuse elements. In short-span bridges, abutments strongly influence longitudinal response, whereas transverse performance depends largely on seismic components such as shear keys and other energy-dissipation devices. Thus, performance assessment requires explicit representation of their hysteretic behavior. This study presents a numerical evaluation of the damping provided by common elements in typical bridge systems, using as reference damage observations from bridges affected by recent interface earthquakes in Mexico. Three-dimensional finite-difference models were developed, and nonlinear response-history analyses were performed to simulate ductile behavior and energy dissipation. The Sig3 hysteretic model available in FLAC3D was used for abutments and foundation soils, while shear keys were represented as nonlinear springs. The results established a relationship between plastic deformation and energy dissipation, showing that incorporating the hysteretic behavior of both soil and sacrificial structural components enhanced the seismic bridge performance assessment, and led to more reliable and cost-efficient designs when inelastic deformation capacity was explicitly included in the numerical simulations.