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Report - PEER - University of California, Berkeley

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1. Facility definition. Same as in Methods 1 and 2.2. Hazard analysis. Determine s EBE as in Method 2.3. Structural analysis. Calculate EDPs using the first-mode spectral response. Wedenote by φ 1 , L 1 and M 1 , the building’s fundamental mode shape, modal excitation,and modal mass, respectively. For example, considering one frame direction, the EDPfor a segment <strong>of</strong> wallboard partition on the m th story would be the interstory driftalong that column line, estimated ass ⎛φ1( 1) −φEBE m+ 1m⎞ L1EDP ≈ (24)2ω ⎜ h ⎟1 ⎝ m ⎠M1where ω 1 = 2π/T 1 , φ 1m is the component <strong>of</strong> the fundamental mode shape at floor m,and h m refers to the height <strong>of</strong> story m.4. Damage and loss analysis. Let c dm denote the mean cost to restore an assemblyfrom damage state dm; it can be calculated by standard cost-estimation principles. Wedenote by c(x) the mean cost to repair one assembly given that it has been exposed toEDP = x. We refer to c(x) as the mean assembly vulnerability function, calculated byN DMc( x) = ∑ cdmp[ DM = dm|EDP = x](25)dm=1where p[DM=dm|EDP=x] is given by Equation [10]. Mean assembly vulnerabilityfunctions can be created and archived for later use. See Porter et al. (2004) forexamples. This is not a new idea. Czarnecki (1973) proposed several, as did Kustu etal. (1982), who normalized by the assembly replacement cost. Because constructioncontractors estimate repairs in terms <strong>of</strong> labor hours and dollar amounts, we find itsimpler to deal with c dm directly (i.e., not normalized). Introducing subscript k toindex particular assemblies and c OP to denote the mean value <strong>of</strong> C OP , PFL is given by( 1 ) ( )NPFL = + c ∑ c x(26)OP k kk = 1where N is the number <strong>of</strong> building assemblies. EAL is then given by Equation [22].3. CASE STUDIESVan Nuys Hotel Building. To compare the three methods, we begin with an actualhighrise hotel building located in Van Nuys, CA. It is a seven-story, eight-by-threebay,nonductile reinforced-concrete moment-frame building built in 1966. It sufferedearthquake damage in 1971 and 1994, after which it was seismically upgraded. Weanalyzed the building in its pre-1994 condition. See Beck et al. (2002) and Porter etal. (2002a) for details <strong>of</strong> the hazard model, structural model, component capacitydistributions and unit repair costs. We performed 20 simulations at each <strong>of</strong> 20 levels<strong>of</strong> IM: S a (1.5 sec, 5%) = 0.1, 0.2, … 2.0g, producing 400 simulated values <strong>of</strong> Y.We took masses as perfectly correlated, normally distributed, with coefficient <strong>of</strong>variation (COV) equal to 0.10, per Ellingwood et al. (1980). We took damping as143

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