As cities become larger and more densely populated the impacts of major earthquake events on city communities become more severe. Improving community resilience to earthquake events relies on the complex relationships that exist between different community stakeholder groups (citizens, businesses, community groups, emergency services, critical infrastructure providers, politicians etc.). This paper reports results from a major EU funded study (LIQUEFACT) that developed a tool for assessing community resilience to Earthquake Induced Liquefaction Disaster (EILD) events. The tool is based on a customised version of the UNDRR Disaster Resilience Scorecard for Cities. The paper reviews alternative approaches to measuring community resilience and describes the process used in the LIQUEFACT project to develop and validate the customised scorecard. The paper presents the results of a questionnaire survey to identify the best generic approach to measure community resilience and a series of semi-structured group interviews to define a range of specific metrics for assessing community resilience to EILD events; and the results of a validation workshop to assess the effectiveness and usability of the customised scorecard. The paper concludes that it is possible to develop a customised version of the UNDRR Scorecard at an appropriate level of granularity to support improved community resilience to earthquake induced soil liquefaction disaster events. The paper also presents key lessons that could assist those developing similar customised versions of the UNDRR scorecard for use in different geographical settings or against different disaster scenarios.
Microzonation for earthquake-induced liquefaction hazard is the subdivision of a territory at a municipal or submunicipal scale in areas characterized by the same probability of liquefaction manifestation for the occurrence of an earthquake of specified intensity.The liquefaction hazard at a site depends on the severity of expected ground shaking as well as on the susceptibility to liquefaction of that site. This in turn depends on geological, geomorphological, hydrogeological and geotechnical predisposing factors. Thus, liquefaction hazard implies the existence of territories characterized by a moderate to high level of intensity of expected ground shaking. Microzonation charts for ground shaking and liquefaction hazard play a key role for the mitigation of seismic risk of an urban centre as they provide a valuable tool for the implementation of prevention strategies and land use planning. The LIQUEFACT project fully addressed the problem of microzoning a territory for earthquake-induced liquefaction hazard in a specific work package. Four municipal testing areas were selected across Europe as peculiar case studies where to construct microzonation charts for earthquake-induced liquefaction hazard. They are located in Emilia-Romagna region (Italy), Lisbon metropolitan area (Portugal), Brežice territory (Slovenia) and Marmara region (Turkey). Their location was identified based on the following criteria: severity of expected seismic hazard, availability of geological and geotechnical data, presence of liquefiable soil deposits, documented cases of liquefaction manifestations occurred in historical earthquakes, representativeness of different geological settings, density of population in selected areas (exposure). This paper illustrates the general procedure developed in LIQUEFACT for the assessment of earthquake-induced liquefaction hazard at urban scale and presents the main achievements of the microzonation studies carried out at the four previously mentioned European testbeds. Since the microzonation studies have been carried out using a shared framework and methodology, this paper has the ambition to serve as technical guidelines for updating the standards and the operational criteria currently used in different countries worldwide to construct seismic microzonation maps of liquefaction hazard. Keywords Liquefaction • Earthquake • Microzonation • Guidelines • LIQUEFACT projectsite-specific geotechnical investigations with pre-existing geological and geotechnical data from public and private sources.Existing information on quaternary deposits and man-made landfills, geomorphological maps, trench pits, boreholes and piezometric monitoring data, shall be stored and analysed in a georeferenced (GIS) environment to identify homogeneous lithostratigraphic units susceptible to liquefaction. These data shall be complemented with field and laboratory geotechnical and geophysical information from pre-existing investigation campaigns. This will eventually allow to plan and implement the complementary experimental investi...
This paper investigates the key parameters that influenced the settlement of a case study building on liquefiable soil in Adapazari (Turkey) during the 1999 Kocaeli earthquake. Ground movements in Adapazari caused large devastation, largely attributed to liquefaction of low plasticity silty soil layers underneath buildings on shallow foundations. The case study soil profile was well characterized by in-situ testing as well as laboratory tests from the Adapazari area. This allowed several different estimates of the building settlement to be obtained through different methods and through a variation in upper and lower bound estimates of the soil parameters. The different methods and different soil properties resulted in a wide range of estimates from 0.004 m to 1.6 m for the building settlement, compared to the observed in-situ value of 0.9 m. Even though the results were varied, the estimation of the liquefied strength of the soil appeared to be a key parameter for the settlement of the case study building. A detailed study with the PLAXIS finite-element software and UBC3D-PLM constitutive model, provided a consistent estimate of the final settlement of 0.9 m compared to the in-situ value. However, the limitation due to the enforced 'undrained' conditions during the dynamic phase of the analyses may have resulted in an inaccurate simulation of the pore water pressure and subsequently could have influenced the estimation of settlement. The modeling of the liquefaction settlements under free-field conditions was also considerably less than the re-consolidation settlements that were obtained through simplified procedures, suggesting that the re-consolidation settlement under the foundation was not modelled accurately. The present paper focuses on the assessment of the settlements due to earthquake-induced liquefaction as part of the research being conducted within the European project LIQUEFACT.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.