Report - PEER - University of California, Berkeley

In this task, general broad categories will be identified such assystems/components that could, if damaged:1. leak2. result in fire ignition3. prevent safe building occupancy4. result in significant repair costs5. result in a serious falling hazard6. prevent critical functionality7. result in serious business lossesThese broad categories might be subdivided into EDP-N sensitivity. Forexample, the following 5 categories of EDP-Ns might be identified.1. Relative Displacement between Floors (drift)2. Peak Floor Acceleration3. Peak Spectral Acceleration of Floor at Fundamental Period of Component4. Peak Velocity of Floor5. Peak Stress in an individual component (e.g., tank or pipe)Individual significant components would next be identified and then categorizedinto one the categories and subcategories. For example, a drywall partition might becategorized as a component that may result in significant repair cost when damagedand subcategorized as having an EDP-N of drift. An uninterruptible power supplymight have be categorized as having critical functionality and be subcategorized ashaving an EDP-N of peak spectral acceleration at the fundamental period of thecomponent. A comprehensive and systematic categorization would be done of allcomponents judged to be significant to either life loss or injury, repair cost ordowntime. Remaining components would not be categorized but instead lumped in afew general categories. At this point we are using the term “bin” as an identifier forthe broad categories.3.3 Develop Generalized Fragility and Loss FunctionsIn this task, generalized fragility functions will be developed for each bin identified inthe previous task. The fragility functions would utilize the EDP-N(s) identified for thebins. The fragility functions would initially be developed based on available resourcesand expert opinion.Nonstructural fragilities are functions that relate the probability that anonstructural component will experience damage greater (or less) than a certain level,given that it is driven to a certain level of response, as measured by the nonstructuralengineering demand parameter. As is the case with building response functions,fragilities are expressed as probability distributions, rather than deterministicrelationships in order to account for the variability and uncertainty inherent in theprocess of predicting nonstructural damage as a function of nonstructural response.132