Report - PEER - University of California, Berkeley

E [ L T | IM ]$ 10 M$ 8 M$ 6 M$ 4 M$ 2 M$ 0 M(a)CollapseNon-collapse0 20 40 60 80 100IM [ Sd (in) ]E [ L T| IM ]$ 10 M$ 8 M$ 6 M$ 4 M$ 2 M$ 0 M(b)Non-structuralStructural0 25 50 75 100IM [ S d (cm) ]dE [ L T| IM ]$ 20 K$ 15 K$ 10 K$ 5 K$ 0 K(c)Non-struct uralSt ruct ural0 25 50 75IM [ S d(cm) ]0 K 1 K 2 K 3 K 4 K 5 KT R = 1 / ν (IM )Figure 8. Loss deaggregation results: (a) contribution of collapse and noncollapselosses to the total loss at different levels of intensity, (b) contribution ofstructural and non-structural losses to the total loss at different levels ofintensity, (c) deaggregation of the expected annual loss.total loss. It can be send that losses are primarily produced by damage to nonstructuralcomponents.Figure 8c presents loss deaggregation results for the expected annual loss. It canbe seen that for the case study building the earthquakes with S d smaller than 50 cm,(return periods, T R of less than 3500 years), contribute 96% to the expected annualloss, 81% of which comes from non-structural components and only 15% correspondsto structural components.5. CONCLUSIONSA methodology is proposed to estimate the seismic performance of buildings in termsof economic losses. The methodology explicitly incorporates the uncertaintiescorresponding to the seismic hazard, to the response of the structure, to the damageincurred in different components and to the repair or replacement cost of damagedcomponents. Generic procedures are proposed to improve the estimation of varioussources of uncertainty that contribute to the loss estimation methodology.Specifically, the concept of fragility surfaces is introduced which leads to smallerdispersions while estimating damage and provides a powerful tool to estimate theconditional probability of system collapse. Furthermore, the effects of correlationbetween losses in individual components are explicitly considered. It is concludedthat the correlation between losses at the component-level can significantly increasethe dispersion in the losses in the building.As part of the study, the use different of different parameters as ground motionintensity measures was investigated. It is concluded that for drift-sensitivecomponents, using inelastic spectral displacement ordinates leads to lower dispersionof building response than those computed using elastic spectral ordinates. Foracceleration-sensitive components, it was observed that peak ground acceleration,PGA, provides smaller levels of dispersion of peak floor accelerations compared tothose computed using elastic spectral ordinates as intensity measure.159