Simplified nonlinear method for the analysis of concrete bridges

The paper starts with assertion that European standards for design of structures in earthquake prone areas are increasingly introducing nonlinear analysis methods into the design practice. The authors present one of them - the so called N2 method - which is used in cases when the bridge response is greatly influenced by only one form of oscillation that is not subject to significant changes. The N2 method is riot used in the analysis of long bridges. The method MPA, used specifically for long bridges, lakes into account higher forms of oscillation. The latter method is also briefly presented.