Effect of seat-type abutment load path and failure mode on seismic response of straight ordinary bridges

• Nonlinear static analysis of 3D seat type abutment-soil system continuum models. • Longitudinal and transverse response with different shear key and backwall configurations. • Comparison with load path and failure modes assumed in simplified bridge boundary conditions. • Increased strength and stiffness contributed by abutment than commonly assumed. • Simplified dynamic models show bridge seismic displacement reduced and forces increased. The...