Keywords: floor-isolation, reliability-based optimization, critical contents, non-parametric stochastic subset optimization, stochastic simulation.

Damage during earthquakes to critical building contents, such as computer servers, or museum artifacts, may lead to significant economic loss due to repair/replacement costs or business interruption. For their protection, application of floor isolation techniques has been gaining increased interest; flexible isolators are used to "decouple" the floor portion containing the group of sensitive structural-contents. Through proper design this implementation may significantly reduce the isolated-component vibration. Application of supplemental dampers, working in tandem with the isolation system, is frequently considered in this context, for reduction of the isolated floor displacement or enhanced vibration suppression. This paper discusses a reliability-based optimization approach for such applications that adequately addresses, at the design stage, the variability related to the earthquake hazard as well as the nonlinear dynamics of the coupled structure/isolation system. The floor isolation system is optimized based on reliability criteria, where the reliability of the system is quantified by the plausibility that the acceleration of the protected contents will not exceed acceptable performance bound, and is calculated using stochastic simulation. A stochastic ground motion model is utilized to characterize the seismic hazard, and an efficient stochastic optimization approach, called non-parametric stochastic subset optimization, is adopted for performing the associated design optimization.

purchase the full-text of this paper (price £20)

go to the previous paper
go to the next paper
return to the table of contents
return to the book description
purchase this book (price £42 +P&P)