Performance-based Seismic Design And Seismic Vulnerability Analysis For Isolated High-rise Buildings

Seismic isolation technique is a modern design technique which could reducestructural seismic response. And it is applied widely into mid-low buildings, asefficiency convenient cushion technique. As the economy development, highbuildings emerged in endlessly. Therefore, a wide development prospect of seismicisolation technique has been promoted. Even though, quipped with good cushiontechnique, there are still some damages in the upper structures with the ultraearthquake action. Isolation bearing might lose its stability for large deformation,which causes partial damages or overall instability. That is to say, high-rise seismicisolation structure is weak in ultra earthquake actions, and seismic vulnerabilityanalysis shall be conducted. As less earthquake tests have been carried out forhigh-rise seismic isolation structure and short of related information, theoreticalanalysis would be the most direct and efficiency way to look into the damage degreeof high-rise seismic isolation structure in ultra earthquake actions. The objective ofthis paper is a high-rise seismic isolation structure with a depth-width ratio less than4that has been wide applied; and seismic vulnerability analysis shall be conducted, thenthe economic losses in earthquake shall be assessed. Specific procedures are asfollowing:(1) AStudy on Seismic Fortification Criterion That Based on State of High-RiseSeismic Isolation StructureClassification of various high-rise seismic isolation structures in the basis offunctions merely; detailed classification done in accordance with depth-width ratio ofwidely used function; reasonable multiple levels of seismic fortification criterion of high-rise seismic isolation shall be provided by research; the lowest State vibrationresistance target shall be given for high-rise seismic isolation structures under variouslevels of earthquake; quantitative index of various states of high-rise seismic isolationstructures shall be studied and a suggested value shall be provided.(2) Seismic Vulnerability Analysis of High-Rise Seismic Isolation Structure:Study objective shall be high-rise seismic isolation buildings which have beenwidely applied with reinforced concrete frame and shear wall which has a depth-widthration less than4. Large-scale finite element analysis software–Perform-3D has beenadopted to build isolation and related non-seismic isolation structure nonlinearanalysis model. With the method of Latin Hypercube, randomness of earthquakeactions and high-rise seismic isolation structures shall be considered, and then80samples of structure-ground motion shall be generated, and nonlinear analysis shall beconducted for each of the sample. The referee index of seismic isolation structures isthe damages level of displacement of isolating system and interlayer displacementangle. The referee index of non-seismic isolation structures is merely the damagedegree of interlayer displacement angle. Seismic fragility curves of high-rise seismicisolation structures and related non-seismic isolation structures could be concluded byregression statistics based on data analysis of a large number. With the contrastiveanalysis of seismic fragility curves before and after the earthquake, good dampingeffect of seismic isolation structures could be verified. At the same time, overallseismic fragility curves of the seismic isolation structures could be provided by gracemethod analysis mode.(3) Assessment of economic losses of high-rise seismic isolation structures:According to the results of seismic fragility analysis of common high-riseseismic isolation structures and related non-seismic isolation structures, assessmentsof economic losses of such structures shall be conducted. On the basis of proposedseismic hazard curve on site and proposed seismic fragility curves of constructions,direct economic losses of seismic isolation structures and non-seismic isolationstructures shall be calculated, including structural damages, indoor and outdoorproperty losses and decoration losses. An economic losses comparative analysis shallbe conducted to both seismic isolation structures and non-seismic isolation structuresto verify the economy efficiency of seismic isolation structures.