Catálogo de publicaciones - revistas

<jats:p> The satisfactory structural behavior observed during large earthquakes and the high seismicity of the country has conditioned the Chilean society to expect immediate occupancy performance level for their buildings under these extreme events, although the seismic design code in Chile mandates only a scope of life safety performance level. Based on observational and statistical evidence from recent strong earthquakes in Chile, it is concluded that the observed seismic resilience of buildings is a consequence of limiting damage, considering that operational performance and life safety are different challenges that require different approaches; furthermore, to provide society with resilient and safe buildings, both challenges must be met simultaneously and not alternatively. The present article describes the concepts, strategies, and future challenges in the context of the Chilean practice, and the authors describe several lessons learned from the design of thousands of concrete buildings that have experienced earthquakes with a magnitude of 8.0 and higher with limited damage; these lessons have proven to be effective in ensuring resilient structural performance under extreme seismic events. </jats:p>

<jats:p> Past earthquakes have illustrated the impacts of reduced hospital functionality due to physical damage resulting in a health service deficit immediately after a major seismic event. In this article, a methodology was developed to quantify the deficit in health care anticipated due to a loss of functionality of a hospital emergency department (ED) and a surge in demand due to regional damage in an earthquake scenario. Earthquake-induced patient arrivals were calculated using multi-severity casualty estimation for the catchment area of the hospital. The surge in patients (demand) was then compared to the ability of the hospital to treat patients (capacity) based on anticipated functionality. Nonlinear response history analysis of the hospital building was performed using simplified structural models, and the structural and non-structural component damage was estimated based on FEMA P-58. Expected damage was linked to the post-earthquake functionality of the ED service areas on each floor by incorporating the fault-tree analysis method. Finally, discrete event simulation was used to evaluate the ED surge capacity, providing hospital performance metrics, such as wait times (WTs) and length of stay (LOS) for patients of ranging acuity. A case study of a hospital in the City of Vancouver subjected to an M<jats:sub>w</jats:sub>9.0 Cascadia Subduction Zone scenario earthquake was presented. Emergency rooms (ERs) were identified as the ED bottleneck during the emergency response. The mean ER WT exceeded its limit of 2 h and reached up to 17 h in the most unfavorable simulation. Likewise, the mean LOS nearly doubled from 6.5 to 12 h, also exceeding the established target of 10 h. The deployment of field hospitals for less severe patients as an emergency plan to mitigate the ED overcrowding was also analyzed to demonstrate that the methodology can be used as a decision support tool to improve healthcare disaster planning. </jats:p>

<jats:p> This study aims to compare the collapse probability of reinforced concrete infilled frames designed in accordance with modern Indian seismic codes. Multiple versions of bare and infilled (both fully and partially) frames are considered. A total of 33 frames are divided into eight sets based on the parameter being varied, namely, the quality and thickness of infills, design code, aspect ratio, and number of stories. The collapse probability is evaluated through multiple stripe analysis with eight stripes corresponding to different return periods. A set of 40 ground motions, consistent with the site-specific uniform hazard spectra corresponding to each return period, is selected. Results suggest that the frames designed for pre-2016 Indian codes perform considerably worse than those designed for post-2016 Indian codes, which are on par with other national codes. The effect of collapse probability of addition of infills to bare frames is found to be negligible to significantly negative depending on factors such as adopted design code, relative strength of infill strut to columns, aspect ratio, and number of stories. Four-story frames perform worse than 8-story frames. Interestingly, the 8-story open first story frames, designed for modern codes, are not found to be significantly more vulnerable than their fully infilled counterparts. </jats:p>

<jats:p> Over the last two decades, the performance-based earthquake engineering (PBEE) framework developed by the Pacific Earthquake Engineering Research (PEER) Center has gained the attention of researchers and practitioners worldwide. This framework was originally focused on quantifying the seismic risk of individual structures. However, with the advent of the “seismic resilience” concept, broader definitions of stakeholders and performance metrics on a regional scale are desirable. In this context, we present a formalized extension of the PEER PBEE framework for its use in groups of structures spatially distributed over a region, herein referred to as RPBEE framework. As an example, we use the RPBEE framework for computing the total number of damaged structures, the expected total economic loss, and the probability distribution of total economic losses within a region. We highlight differences with the original PEER framework and challenges arising from the implementation of the new RPBEE framework for future research and adoption, along with potential ways to overcome them. </jats:p>