Assessment, upgrading and strengthening of ageing civil infrstructure is a major task in many countries. Nonlinear Finite Element Analysis is a powerful tool to determine the ‘hidden’ capacity of existing concrete structures an possibly extend its life-time without loss of safety. Layered models for beam and shell elements allow for relatively rapid FEM analysis of concrete structures and can be an efficient alternative to FE models with volumetric elements for true-scale analysis in preliminary assessment tages. Standard beam and shell models are limited to flexural analysis which can result into unsafe predictions of ultimate loading capacity and ductility of structures critical to shear. This work presents the development and implementation of reduced FE models including the effect of shear in the software DIANA, validation against lab tests and comparison with plane stress FE models. The model is finally applied to the analysis of a full-scale bridge.
