The assessment of the seismic performances of an old concrete bridge was conceived within the RETRO Transnational Activity funded by the SERIES research project. The installation of a couple of isolation devices -one per column- for each pier portal frame interposed between the cap beam and the deck was proposed as seismic retrofit, which fully comply with Eurocode 8 requirements. A comprehensive set of hybrid simulations was conceived to simulate the dynamic response of the old 400m span Rio Torto Viaduct both in the isolated and the non-isolated cases. In order to support the pseudo-dynamic test design, a refined fiber based FE model of the bridge was implemented in the well-known OpenSEES software; time history analyses highlighted appreciable nonlinearities in the dynamic response of the system already under the Serviceability Limit State (SLS). As a consequence, a Numerical Substructure (NS) capable of reproducing such nonlinear behaviour was deemed necessary. Nonetheless, implementation is-sues relevant to typical solving time dictated by the controller time step, made the use of complex fiber based FE models not suitable for testing purposes. In this perspective, the paper presents the design of a suitable NS, which is based on a ra-tional and nonlinear reduction of the aforementioned OpenSEES Reference Model (RM). Moreover, in order to impose a consistent degradation of physical and nu-merical piers, a testing procedure based on recursive identification and model up-dating sessions is proposed. Developed numerical tools and simulations are pre-sented and discussed.
Abbiati, G., Bursi, O.s., Cazzador, E., Ceravolo, R., Mei, Z., Paolacci, F., et al. (2015). Pseudo-dynamic testing based on non-linear dynamic substructuring of a reinforced concrete bridge. In SERIES Concluding Workshop – Joint with US-NEES, “Earthquake Engineering Research Infrastructures”,JRC-Ispra, May 28-30, 2013, In Memory of Prof. Roy Severn (pp. 83-98). Springer [10.1007/978-3-319-10136-1_7].
Pseudo-dynamic testing based on non-linear dynamic substructuring of a reinforced concrete bridge
PAOLACCI, Fabrizio;
2015-01-01
Abstract
The assessment of the seismic performances of an old concrete bridge was conceived within the RETRO Transnational Activity funded by the SERIES research project. The installation of a couple of isolation devices -one per column- for each pier portal frame interposed between the cap beam and the deck was proposed as seismic retrofit, which fully comply with Eurocode 8 requirements. A comprehensive set of hybrid simulations was conceived to simulate the dynamic response of the old 400m span Rio Torto Viaduct both in the isolated and the non-isolated cases. In order to support the pseudo-dynamic test design, a refined fiber based FE model of the bridge was implemented in the well-known OpenSEES software; time history analyses highlighted appreciable nonlinearities in the dynamic response of the system already under the Serviceability Limit State (SLS). As a consequence, a Numerical Substructure (NS) capable of reproducing such nonlinear behaviour was deemed necessary. Nonetheless, implementation is-sues relevant to typical solving time dictated by the controller time step, made the use of complex fiber based FE models not suitable for testing purposes. In this perspective, the paper presents the design of a suitable NS, which is based on a ra-tional and nonlinear reduction of the aforementioned OpenSEES Reference Model (RM). Moreover, in order to impose a consistent degradation of physical and nu-merical piers, a testing procedure based on recursive identification and model up-dating sessions is proposed. Developed numerical tools and simulations are pre-sented and discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
