| Earthquakes and Structures Volume 10, Number 6, June 2016, pages 1451-1465 DOI: https://doi.org/10.12989/eas.2016.10.6.1451 | |
Seismic vibration control of bridges with excessive isolator
displacement | |
Bijan K. Roy, Subrata Chakraborty and Sudib K. Mishra
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| Abstract [Buy Article] | |
| The effectiveness of base isolation (BI) systems for mitigation of seismic vibration of bridges have been extensively studied in the past. It is well established in those studies that the performance of BI system is largely dependent on the characteristics of isolator yield strength. For optimum design of such systems, normally a standard nonlinear optimization problem is formulated to minimize the maximum response of the structure, referred as Stochastic Structural Optimization (SSO). The SSO of BI system is usually performed with reference to a problem of unconstrained optimization without imposing any restriction on the maximum isolator displacement. In this regard it is important to note that the isolator displacement should not be arbitrarily large to fulfil the serviceability requirements and to avoid the possibility of pounding to the adjacent units. The present study is intended to incorporate the effect of excessive isolator displacement in optimizing BI system to control seismic vibration effect of bridges. In doing so, the necessary stochastic response of the isolated bridge needs to be optimized is obtained in the framework of statistical linearization of the related nonlinear random vibration problem. A simply supported bridge is taken up to elucidate the effect of constraint condition on optimum design and overall performance of the isolated bridge compared to that of obtained by the conventional unconstrained optimization approach. | |
| Key Words | |
| seismic vibration; base isolation; bridges; stochastic structural optimisation; constrained optimisation | |
| Address | |
| Bijan K. Roy: Department of Civil Engineering, National Institute of Technology, Silchar, India Subrata Chakraborty: Department of Civil Engineering, Indian Institute of Engineering Science and Technology, Shibpur, India Sudib K. Mishra: Department of Civil Engineering, Indian Institute of Technology, Kanpur, India | |
