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Traditional vulnerability methodologies rely on collecting building data through time consuming surveys and visual screening. Geospatial infrastructure systems have rapidly evolved and today we can access massive geospatial data. Digital cadastral databases combine location, attributes, and temporal information for building stock. This paper proposes a GIS-based framework to estimate seismic vulnerability and losses from cadastral data only. The framework is rooted on well-known displacement-based procedures and uses probabilistic models of the building structural capacity. A featured application to 287,503 housing units in metropolitan area of Granada is presented to showcase outputs for decision-making: performance displacement, damage level and repair cost. [ABSTRACT FROM AUTHOR]

This paper addresses the effect of the importance factor on seismic performance by comparing four prototype health facilities located in a medium seismicity region in Europe. The buildings have Reinforced Concrete (RC) frame structures designed with importance factors 1.0, 1.2, 1.4, and 1.5. Performance assessment is based on the FEMA P-58-1 methodology. This study comprises nonlinear time history analyses of the building structure, the identification of structural and nonstructural performance groups, the probabilistic expression of structural response, and the quantification of damage and repair costs by means of fragility relations. The evaluation of the prototype buildings is the basis to discuss the impact of the importance factor on the performance under occasional and rare ground motions. This works reveals that seismic performance of the analyzed prototypes is not appropriate in terms of damage, loss of functionality and repair costs. [ABSTRACT FROM AUTHOR]

SUMMARY This paper presents shake-table tests conducted on a two-fifths-scale reinforced concrete frame representing a conventional construction design under current building code provisions in the Mediterranean area. The structure was subjected to a sequence of dynamic tests including free vibrations and four seismic simulations in which a historical ground motion record was scaled to levels of increasing intensity until collapse. Each seismic simulation was associated with a different level of seismic hazard, representing very frequent, frequent, rare and very rare earthquakes. The structure remained basically undamaged and within the inter-story drift limits of the 'immediate occupancy' performance level for the very frequent and frequent earthquakes. For the rare earthquake, the specimen sustained significant damage with chord rotations of up to 28% of its ultimate capacity and approached the upper bound limit of inter-story drift associated with 'life safety'. The specimen collapsed at the beginning of the 'very rare' seismic simulation. Besides summarizing the experimental program, this paper evaluates the damage quantitatively at the global and local levels in terms of chord rotation and other damage indexes, together with the energy dissipation demands for each level of seismic hazard. Further, the ratios of column-to-beam moment capacity recommended by Eurocode 8 and ACI-318 to guarantee the formation of a strong column-weak beam mechanism are examined. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This article investigates experimentally the application of health monitoring techniques to assess the damage on a particular kind of hysteretic (metallic) damper called web plastifying dampers, which are subjected to cyclic loading. In general terms, hysteretic dampers are increasingly used as passive control systems in advanced earthquake-resistant structures. Nonparametric statistical processing of the signals obtained from simple vibration tests of the web plastifying damper is used here to propose an area index damage. This area index damage is compared with an alternative energy-based index of damage proposed in past research that is based on the decomposition of the load–displacement curve experienced by the damper. Index of damage has been proven to accurately predict the level of damage and the proximity to failure of web plastifying damper, but obtaining the load–displacement curve for its direct calculation requires the use of costly instrumentation. For this reason, the aim of this study is to estimate index of damage indirectly from simple vibration tests, calling for much simpler and cheaper instrumentation, through an auxiliary index called area index damage. Web plastifying damper is a particular type of hysteretic damper that uses the out-of-plane plastic deformation of the web of I-section steel segments as a source of energy dissipation. Four I-section steel segments with similar geometry were subjected to the same pattern of cyclic loading, and the damage was evaluated with the index of damage and area index damage indexes at several stages of the loading process. A good correlation was found between area index damage and index of damage. Based on this correlation, simple formulae are proposed to estimate index of damage from the area index damage. [ABSTRACT FROM AUTHOR]