Zero-dimensional seismic design of bridge abutments: a double macroelement approach

Simplicity is a key element in design. It requires synthesis, in order to provide a straightforward interpretation of a phenomenon. Recent studies have shown that abutments are critical components in the seismic design of bridges, and that many technical provisions oversimplify some dominant factors of their dynamic response, that could be considered only through onerous modelling techniques. Hence, this study proposes a tool that requires a minimal calculation effort for the seismic design of abutments. It consists of the combination of two complementary macroelements: one that describes the response of the soil-abutment system and one simulating the dynamic response of the bridge superstructure. The macroelements are lumped at the abutment-deck contact and reproduce salient features of the dynamic response: frequency dependence, nonlinearity and directional coupling. This approach is implemented in OpenSees and is validated against the results of a fully coupled soil-bridge finite-el...