ABSTRACT
A number of levels of analytical approximations for viaduct structures are possible. Since the criteria for the choice of an appropriate method are not clearly defined, an attempt is made to provide some guidance to the choice. Several idealized viaducts with continuous deck are analyzed in the transverse direction. In addition, a typical viaduct structure is used as a practical example. Some important parameters that influence the response of viaducts are identified. They include: the stiffness ratio of the deck and piers, the ratio of the torsional and translational stiffness of the structure, eccentricity, and boundary conditions at the abutments. An attempt is made to quantify some of these parameters. Although viaducts are simple in their structural concept, it is the general conclusion, that their seismic response in the transverse direction may be quite complex. Therefore, some degree of sophistication is needed in their analysis. Simplified inelastic procedures are likely to be the most useful in the future generation of codes. A general purpose procedure of this type is still to be defined.
