A knowledge-based software for the preliminary design of seismically isolated bridges

Abstract

Seismic design of isolated bridges involves conceptual, preliminary and detailed structural design. However, despite the variety of commercial software currently available for the analysis and design of such systems, conceptual and preliminary design can prove to be a non-straightforward procedure because of the sensitivity of bridge response on the initial decisions made by the designer of the location, number and characteristics of the bearings placed, as well as on a series of broader criteria such as serviceability, target performance level and cost-effectiveness of the various design alternatives. Given the lack of detailed design guidelines to ensure, at this preliminary stage, compliance with the above requirements, a "trial and error" procedure is typically followed in the design office to decide on the most appropriate design scheme in the number and location of the bearing systems; the latter typically based on engineering judgment to balance performance with cost. To this end, the particular research effort aims to develop a decision-making system for the optimal preliminary design of seismically isolated bridges, assumed to respond as single degree of freedom (SDOF) systems. The proposed decision-making process is based on the current design provisions of Eurocode 8, but is complemented by additional criteria set according to expert judgment, laboratory testing and recent research findings, while using a combined cost/performance criterion to select from a database of bearings available on the international market. Software is also developed for the implementation of the system. The paper concludes with the application, and essentially the validation of the methodology and software developed through more rigorous MDOF numerical analysis for the case of a real bridge. © Springer Science+Business Media B.V. 2011

A parametric study on the axial behaviour of elastomeric isolators in multi-span bridges subjected to horizontal seismic excitations

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Numerical study on the response of steel-laminated elastomeric bearings subjected to variable axial loads and development of local tensile stresses

“…Their use in structural applications dates in the late 1950s, but research and development of materials and design of the isolators continued over the years until today [1][2]. The application of steel-laminated elastomeric bearings for the seismic isolation of bridges [3] and buildings became morepopularafter the early 1990s, [4][5]. Bearings are used to accommodate movements of the structures, such as dynamic (e.g.…”

Shaking Table Study of the Seismic Interaction of an Isolated Bridge Deck With the Abutment Utilizing Small-Scale Models and Numerical Simulations

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