Abstract: After an earthquake, non-negligible residual displacements can occur if the isolation system does not possess a good restoring capability. In this paper the residual displacement of friction pendulum isolation systems is investigated through an extensive experimental campaign of controlled-displacement and seismic input experiments, both under uni-directional motion. A sequence of natural earthquakes was applied in three different lubrication conditions of sliding surfaces, corresponding to High, Medium and Low Friction. In order to improve current design method of sliding isolation systems, a simple equation for the estimation of the maximum expected residual displacements is proposed and compared with the experimental results.

• Publication Date: 26-Sep-2016
• DOI: 10.15224/978-1-63248-105-4-27
• Views: 0
• Downloads: 0

Abstract: Buckling Restrained Braces (BRBs) have been found to perform better than conventional braces in resisting cyclic lateral loads due to earthquakes. The tendency of a brace to undergo global buckling is resisted by a sleeve tube and concrete in between. The bond between the core and concrete is broken to ensure that only the core gets loaded. This also decouples the strength from the stiffness and it is possible to vary them independent of each other. The paper describes the cyclic tests on two BRBs of identical strength but slightly different stiffness and concludes that much work needs to be done to evaluate the optimum values for a particular structure.

• Publication Date: 26-Sep-2016
• DOI: 10.15224/978-1-63248-105-4-28
• Views: 0
• Downloads: 0