A MATERIALLY NONLINEAR FINITE ELEMENT MODEL FOR THE ANALYSIS OF CURVED REINFORCED CONCRETE BOX-GIRDER BRIDGES

A layered finite element model with material nonlinearity is developed to trace the nonlinear response of horizontally curved reinforced concrete box girder bridges. Concrete is treated as an orthotropic nonlinear material and reinforcement is modeled as an elastoplastic strain-hardening material. Due to the fact that the flanges and webs of the structure are much different both in configuration and in the state of stresses, two types of facet shell elements, namely, the triangular generalized conforming element and the rectangular nonconforming element, are adopted to model them separately. A numerical example of a multi-cell box girder bridge is given and the results are compared favorably with the experimental results previously obtained.