COMPARISON OF SEISMIC FRAGILITY OF FREE STANDING EQUIPMENT USING CURRENT TESTING PROTOCOLS AND RECORDED BUILDING FLOOR MOTIONS

Present structural design is concerned with life protection and collapse prevention of a structure. The next generation of design codes is poised to introduce function protection for critical buildings (such as hospitals), for which protecting nonstructural components and building contents is a priority. This priority is due to the fact that the majority cost of a structure lies in nonstructural components and building contents such as partition walls, suspended ceilings, furnishings, equipment (electrical and mechanical), distributed lines, etc. As a result, even though a structure avoids catastrophic collapse, damage repair and replacement costs of nonstructural components generate a significant expense for building owners. This means that nonstructural components are the most important factor in seismic losses. Additionally, past earthquakes have demonstrated that for essential or priority buildings (such as hospitals), although the structure remains standing, damage to nonstructural components renders the facility inoperable, and therefore useless to the community around it during the moment of largest need for health services. It is therefore important to evaluate the fragility of nonstructural components. Some protocols for evaluating the fragility of nonstructural components already exist, and they have been developed for the seismic demands generally imposed upon linear and slightly nonlinear systems of single and multiple degrees of freedom. This paper presents an analysis and comparison of seismic fragility of freestanding, bodies obtained through computer simulation using current testing protocols. It also determines which protocol is the most conservative for conducting fragility analysis.