Добірка наукової літератури з теми "Low-To-Moderate seismicity"

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Статті в журналах з теми "Low-To-Moderate seismicity":

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C.V.R.Murty and Javed N. Malik. "Challenges of Low-to-Moderate Seismicity in India." Electronic Journal of Structural Engineering, no. 01 (March 28, 2008): 77–87. http://dx.doi.org/10.56748/ejse.8801.

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India is a vast country that is growing even faster. Particularly over the last decade, there has been a sudden spurt in the construction activity in the country, especially in the large low-to-moderate seismic regions of the country. But, no systems are in place to regulate these massive constructions to ensure seismic safety. This paper raises the challenges in the current practice and provides measures to overcome them. In particular, the paper argues for separate provisions for the design and construction of structures in low-tomoderate seismic regions.
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Fardipour, M., E. L.umantarna, N. Lam, J. Wilson, and E. Gad. "Drift Demand Predictions in Low to Moderate Seismicity Regions." Australian Journal of Structural Engineering 11, no. 3 (January 2010): 195–206. http://dx.doi.org/10.1080/13287982.2010.11465066.

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Mergos, Panagiotis E., and Katrin Beyer. "Loading protocols for European regions of low to moderate seismicity." Bulletin of Earthquake Engineering 12, no. 6 (March 9, 2014): 2507–30. http://dx.doi.org/10.1007/s10518-014-9603-3.

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Kim, Hyung-Joon, and Dong-Hyeon Shin. "Analytical Evaluation of MCE Collapse Performance of Seismically Base Isolated Buildings Located at Low-to-Moderate Seismicity Regions." Applied Sciences 10, no. 24 (December 21, 2020): 9150. http://dx.doi.org/10.3390/app10249150.

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The promising seismic response emerged by the concept of base isolation leads to increasing practical applications into buildings located at low-to-moderate seismicity regions. However, it is questionable that their collapse capacities can be ensured with reasonable reliability, although they would be designed according to a current seismic design code. This paper aims to investigate the collapse capacities of isolated buildings governed by the prescribed design criteria on the displacement and strength capacities of the employed isolation systems. In order to evaluate their collapse capacity under maximum considered earthquakes (MCEs), simplified numerical models are constructed for a larger number of nonlinear incremental dynamic analyses. The influential factors on the collapse probabilities of the prototype buildings are found out to specifically suggest the potential modifications of the design requirements. Although the MCE collapse probabilities of all isolated buildings are smaller than those expected for typical non-isolated buildings, these values are significantly different according to the degree of seismicity. The MCE collapse probabilities are dependent upon the governing collapse mechanism and the total system uncertainty. For the prototype buildings located at low-to-moderate seismicity regions, this study proposed the acceptable uncertainty to achieve a similar collapse performance to the corresponding buildings built at high seismicity regions.
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Nordenson, Guy J. P., and Glenn R. Bell. "Seismic Design Requirements for Regions of Moderate Seismicity." Earthquake Spectra 16, no. 1 (February 2000): 205–25. http://dx.doi.org/10.1193/1.1586091.

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The need for earthquake-resistant construction in areas of low-to-moderate seismicity has been recognized through the adoption of code requirements in the United States and other countries only in the past quarter century. This is largely a result of improved assessment of seismic hazard and examples of recent moderate earthquakes in regions of both moderate and high seismicity, including the San Fernando (1971), Mexico City (1985), Loma Prieta (1989), and Northridge (1994) earthquakes. In addition, improved understanding and estimates of older earthquakes in the eastern United States such as Cape Ann (1755), La Malbaie, Quebec (1925), and Ossippe, New Hampshire (1940), as well as monitoring of micro-activity in source areas such as La Malbaie, have increased awareness of the earthquake potential in areas of low-to-moderate seismicity. Both the hazard and the risk in moderate seismic zones (MSZs) differ in scale and kind from those of the zones of high seismicity. Earthquake hazards mitigation measures for new and existing construction need to be adapted from those prevailing in regions of high seismicity in recognition of these differences. Site effects are likely to dominate the damage patterns from earthquakes, with some sites suffering no damage not far from others, on soft soil, suffering near collapse. A number of new seismic codes have been developed in the past quarter century in response to these differences, including the New York City (1995) and the Massachusetts State (1975) seismic codes. Over the same period, the national model building codes that apply to most areas of low-to-moderate seismicity in the United States, the Building Officials and Code Administrators (BOCA) Code and the Southern Standard Building Code (SSBC), have incorporated up-to-date seismic provisions. The seismic provisions of these codes have been largely inspired by the National Earthquake Hazard Reduction Program (NEHRP) recommendations. Through adoption of these national codes, many state and local authorities in areas of low-to-moderate seismicity now have reasonably comprehensive seismic design provisions. This paper will review the background and history leading up to the MSZ codes, discuss their content, and propose directions for future development.
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R.K.L. Su. "Seismic Behaviour of Buildings with Transfer Structures in Low-to- Moderate Seismicity Regions." Electronic Journal of Structural Engineering, no. 01 (March 28, 2008): 99–109. http://dx.doi.org/10.56748/ejse.9001.

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A literature review has been conducted aimed at improving the general understanding of the seismic response of concrete buildings with transfer structures in low-to-moderate seismicity regions. This paper summarizes and discusses the existing codified requirements for transfer structure design under seismic conditions. Based on the previous shaking table test results and numerical findings, the seismic effects on the inelastic behaviours of transfer structures are investigated. The mechanisms for the formation of a soft storey below transfer floors, the abrupt change in inter-storey drift near transfer storeys and shear concentration due to local deformation of transfer structures are developed. Design principles have been established for controlling soft-storey type failure and minimizing shear concentration in exterior walls supported by transfer structures. The influence of the vertical positioning of transfer floors on the seismic response of buildings has also been reviewed.
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Tsang, Hing-Ho. "Evaluation of codified elastic design spectrum models for regions of low-to-moderate seismicity." Soil Dynamics and Earthquake Engineering 70 (March 2015): 148–52. http://dx.doi.org/10.1016/j.soildyn.2014.12.016.

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Kanyilmaz, Alper, Hervé Degée, and Carlo Andrea Castiglioni. "An adjusted design approach for concentrically braced frames in low-to-moderate seismicity areas." Bulletin of Earthquake Engineering 16, no. 9 (July 2, 2018): 4159–89. http://dx.doi.org/10.1007/s10518-018-0402-0.

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Wilson, John, Nelson Lam, and L. Pham. "Development of the New Australian Earthquake Loading Standard." Electronic Journal of Structural Engineering, no. 01 (March 28, 2008): 25–31. http://dx.doi.org/10.56748/ejse.8301.

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This paper outlines the development of the Australian Earthquake Loading Standard, AS1170.4 published in 2007. Australia is a country of low to moderate seismicity with a number of Magnitude 6.8 events recorded and a moderate 5.6 magnitude event in Newcastle in 1989 that killed 13 people and caused in excess of $2 Billion damage. A new design response spectrum has been developed for Australia which has a very good representation of accelerations, velocities and displacements for rock and soft soil sites. The methodology used to develop the spectrum could be extended to other countries of low to moderate seismicity. The Standard introduces a tiered approach to earthquake loading from a simplistic force based approach to a more complex displacement based method. The displacement based method has significant advantages in low seismic regions and allows designers to design for gravity and wind loads and then to carry out a displacement check for earthquake effects.
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Islam, A. B. M. Saiful, Syed Ishtiaq Ahmad, Mohammed Jameel, and Mohd Jumaat Zamin. "Seismic Base Isolation for Buildings in Regions of Low to Moderate Seismicity: Practical Alternative Design." Practice Periodical on Structural Design and Construction 17, no. 1 (February 2012): 13–20. http://dx.doi.org/10.1061/(asce)sc.1943-5576.0000093.

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Дисертації з теми "Low-To-Moderate seismicity":

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Lens, John Edward. "Quantifying the Seismic Vulnerability of Bridges in Low to Moderate Seismicity Regions." ScholarWorks @ UVM, 2019. https://scholarworks.uvm.edu/graddis/1066.

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The U.S. Congressional Research Service issued a report for Congress in May 2016, entitled” Earthquake Risk and U.S. Highway Infrastructure: Frequently Asked Questions” which highlighted the absence of a national database on the status of seismic vulnerability of bridges or other infrastructure, and thus no estimate of costs to retrofit vulnerable bridges. Low to moderate seismicity regions exist in each of the continental United States, with over 30 states having mostly or entirely low-to-moderate seismicity. Resources at state transportation agencies and municipalities are focused on higher seismicity regions, creating a gap in quantifying the system-wide seismic vulnerability despite an overall aging bridge inventory, much of which was built before current seismic design standards. This research addressed this data gap and reduces barriers to quantifying seismic vulnerability of existing bridges in low-to-moderate seismicity regions. The work included nonlinear dynamic numerical modeling of typical multiple span bridge configurations in both pristine and deteriorated conditions, by subjecting them to seventy ground motions across four low-to-moderate seismic hazard levels, to evaluate their seismic performance. These typical bridge configurations represent over 160,000 bridges, which comprise 55 % of the multiple span bridges nationwide. The research results indicate that there is an overall low probability of significant seismic damage to these typical bridges in such regions. The results also show that current seismic hazard thresholds used for the design of new bridges, and for retrofit of existing bridges, which provide the basis for exempting some bridges from specific seismic analysis and design, can underestimate the expected seismic forces. Those results can be used to refine those exemption thresholds to provide appropriate protection against potential seismic damage in those cases. The study results also formed the basis for a system-wide rapid seismic vulnerability screening algorithm developed for the Vermont bridge inventory, which is applicable to other states with low to moderate seismicity regions.
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Sheikh, Md Neaz. "Simplified analysis of earthquake site response with particular application to low and moderate seismicity regions." Thesis, Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2353008x.

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Rockett, Paul. "On the estimation of seismic risk in low to moderate seismicity areas for purposes of insurance : a case study of Israel." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621954.

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Gouache, Corentin. "Générateur stochastique de séismes en contexte de sismicité faible à modérée : des données à l'aléa. Cas de la France métropolitaine." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0136.

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La France métropolitaine est éloignée des principales limites de plaques tectoniques. De ce fait, l'origine de la sismicité est plus difficile à comprendre que dans les régions actives localisées le long des limites de plaques. De plus, les données sismiques disponibles (séismes, accumulation des contraintes dans le sol, failles, mécanismes au foyer, etc.) y sont moins nombreuses. Ces observations sont deux des principaux freins rencontrés lorsque l'on souhaite caractériser l'aléa sismique sur un territoire à sismicité faible à modérée. L'approche proposée dans cette thèse s'appuie sur un générateur stochastique produisant des séismes synthétiques en combinant des observations de terrain et des connaissances théoriques sur la sismicité du territoire d'étude. Ce générateur de séismes se divise en trois parties : (i) le tirage temporel des séismes principaux, suivi du (ii) tirage de leur localisation conditionné par la magnitude et enfin de (iii) la production de répliques associées aux séismes principaux. Le tirage temporel est réalisé à l'aide d'une distribution fréquence – magnitude (DFM) calculée sur l'intégralité du territoire d'étude via la méthode non paramétrique des temps de latence. Ce calcul à l'échelle du territoire entier permet d'augmenter le nombre de données, de diminuer les périodes de retour et donc d'estimer les fréquences de chaque magnitude directement à partir des données. Une attention particulière a été portée à la méthode des temps de latence afin de pallier la faible quantité de données observées notamment pour les fortes magnitudes. Le tirage spatial des séismes principaux nécessite, quant à lui, une régionalisation et une densité spatiale caractérisant la sismicité. La régionalisation permet de limiter spatialement la magnitude maximale autorisée des séismes synthétiques. La localisation d'un séisme synthétique d'une magnitude donnée est tirée dans la densité spatiale uniquement au sein des régions autorisant cette magnitude. Les répliques sont ensuite générées autour des séismes principaux à partir de la loi de Bath et de la distribution proportion – magnitude des répliques. L'aléa associé à chaque séisme (principal et réplique) généré est calculé à l'aide de modèles de prédiction des mouvements du sol pondérés. La pondération est dépendante de la magnitude du séisme et de la distance séisme – site. Cette pondération s'effectue en utilisant la base de données européenne d'accélérations du sol RESORCE. Enfin, l'observation en un site donné des aléas produits par les séismes synthétiques sur un million d'années permet d'estimer les probabilités annuelles de dépassement de seuils d'aléa donnés
French mainland seismicity is considered as low to moderate due to its remoteness from tectonic plate boundaries. A first consequence is that the origins of its seismicity are harder to understand than in active regions close to tectonic plate boundaries. Another consequence is the lack of available data (earthquakes recorded but also strain rates, active faults...). These two observation make difficult to estimate seismic hazard in low-to-moderate seismic areas. The proposed approach is to generate synthetic earthquakes by combining observation and theoretical knowledge on the seismicity of the studied territory. This generator is based on a three-step scheme: (i) the temporal draw of main shocks, (ii) their spatial draw conditioned by magnitude and finally (iii) the generation of aftershocks they produce. The temporal step needs a recurrence rate. Past seismicity of the whole studied area is analysed thanks to the non-parametric inter event time method in order to obtain this wished recurrence rate. Computing the recurrence rate at the whole territory scale allows to keep the maximum quantity of data, reduce the return periods and so estimate main shock frequencies directly form observed data for each magnitude. An implementation has been developed to overcome the accuracy fall of the inter event time method observed when data are sparse. The spatial step needs a regionalization and a spatial density representing seismicity. The regionalization allows maximum magnitude limitation in space: each region is characterized by an allowed maximal magnitude. Location of a synthetic earthquake with a given magnitude is drawn in the spatial density only within regions that allow this magnitude. Aftershocks are generated around main shocks thanks to the Bath law and the proportion – magnitude distribution of aftershocks. The seismic hazard produced by each of the generated earthquakes (main shocks and aftershocks) is computed thanks to a set of weighted Ground-Motion Prediction Equations. The weights are obtained as function of magnitude and distance thanks to The European ground-motion database RESORCE. Finally, from direct observation of the seismic hazard produced by synthetic earthquakes over one million years, annual probabilities of exceedance can be calculated with ease

Частини книг з теми "Low-To-Moderate seismicity":

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Raza, Saim, Hing-Ho Tsang, Scott J. Menegon, and John L. Wilson. "Seismic Performance Assessment of Reinforced Concrete Columns in Regions of Low to Moderate Seismicity." In Resilient Structures and Infrastructure, 269–86. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7446-3_11.

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Lumantarna, E., N. Lam, and J. Wilson. "Seismic assessment of asymmetrical buildings in low to moderate seismicity regions." In Incorporating Sustainable Practice in Mechanics and Structures of Materials, 347–52. CRC Press, 2010. http://dx.doi.org/10.1201/b10571-62.

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Zhu, Junjiang, Sanzhong Li, Huilin Xing, Changsheng Wang, Guoming Yang, Zixiang Xiong, Shengsheng Zhang, and Xianzhi Cao. "Large-magnitude oceanic intraplate seismicity: Implications for lithosphere evolution." In In the Footsteps of Warren B. Hamilton: New Ideas in Earth Science. Geological Society of America, 2022. http://dx.doi.org/10.1130/2021.2553(10).

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ABSTRACT We analyzed 37 large oceanic intraplate earthquakes (M >6). The largest (M >7) are mainly concentrated under the Indian Ocean. Moderate events (6 < M < 7) are sparsely distributed under the Indian Ocean and other oceans where lithospheric ages are between 90 Ma and 20 Ma. Oceanic intraplate events related to mantle plumes or hotspots are rare, though low-velocity anomalies beneath hotspots are a common feature. Tomographic cross sections for Indian Ocean areas with large intraplate earthquakes indicate strong heterogeneity in the mantle. These earthquakes are explained by shallow stress variations caused by a combination of tectonic forces including slab-pull, ridge-push, drag by mantle flow, plume-push, and buoyancy forces as a consequence of low-velocity anomalies in the mantle. Oceanic intraplate seismicity in the Indian Ocean is related to the large-scale, low-velocity anomaly structure around the Ninety East Ridge.
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Shahi, R., N. Lam, E. Gad, and J. Wilson. "Quasi-static testing protocol for simulating earthquake conditions in regions of low-moderate seismicity." In From Materials to Structures: Advancement through Innovation, 485–90. CRC Press, 2012. http://dx.doi.org/10.1201/b15320-84.

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Тези доповідей конференцій з теми "Low-To-Moderate seismicity":

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Aaqib, Muhammad, Shamsher Sadiq, Duhee Park, Youssef M. A. Hashash, and Menzer Pehlivan. "Importance of Implied Strength Correction for 1D Site Response at Shallow Sites at a Moderate to Low Seismicity Region." In Geotechnical Earthquake Engineering and Soil Dynamics V. Reston, VA: American Society of Civil Engineers, 2018. http://dx.doi.org/10.1061/9780784481462.043.

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Degée, Hervé, Yves Duchêne, and Benno Hoffmeister. "Performances of moment resisting frames with slender composite sections in low-to-moderate seismic areas." In 12th international conference on ‘Advances in Steel-Concrete Composite Structures’ - ASCCS 2018. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/asccs2018.2018.7150.

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The aim of the recently completed European research program Meakado is therefore to study design options with requirements proportioned to the actual seismic context of constructions in areas characterized by a low or moderate seismic hazard, contrary to most researches aiming at maximizing the seismic performances. In this general framework, specific investigations have been carried out regarding typical beam profiles commonly used for multi-bay - multi-storey composite frames. In a first stage, experimental tests on class-3 composite beam-to-column connections were performed. The measurement results were evaluated with regard to the development of the hysteretic behavior with particular emphasis on the degradation. These test results have been used as reference for the calibration and validation of numerical model aiming at extending the scope of the experimental outcomes through appropriate parametric variations regarding the behavior of nodal connections as well as towards the global analysis and behavior of structures made of class 3 and 4 profiles. Numerical investigations of the global performance of composite frames with slender cross-sections are then performed resorting to the numerical model previously calibrated with respect to the experimental tests and additional simulations at node level. Results are compared to the performance of an equivalent frame made of compact steel profiles. Attention is paid to the effects of strength and stiffness degradation due to local buckling. The analysis of the results is specifically focusing on the comparison of the rotation capacity of the slender section with the actual rotation demand imposed by a moderate intensity earthquake. Based on the outcomes of these investigations, practical design recommendations are finally derived for multi-storey, multi-bay moment resisting frames with type b (full composite action) beam-to column connections located in low and moderate seismicity regions.
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KARALAR, Memduh, and Murat DİCLELİ. "COMPARATIVE ASSESSMENT OF THE EFFICIENCY OF SEISMIC İSOLATION FOR SEISMIC RETROFITTING OF HIGHWAY BRIDGES IN REGIONS OF LOW-TO-MODERATE SEISMICITY." In The 16th World Conference on Seismic Isolation, Energy Dissipation and Active Vibration Control of Structures. Russian Association for Earthquake Engineering and Protection from Natural and Manmade Hazards, 2019. http://dx.doi.org/10.37153/2686-7974-2019-16-411-417.

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Reuland, Yves, Lorenzo Diana, Pierino Lestuzzi, and Ian F. C. Smith. "Using data interpretation to enhance post-seismic decision making at urban scale." In IABSE Symposium, Guimarães 2019: Towards a Resilient Built Environment Risk and Asset Management. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2019. http://dx.doi.org/10.2749/guimaraes.2019.1789.

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<p>Recent events around the globe are evidence that earthquake action is still a threat for many structures. Low replacement and retrofitting rates of urban housing mean that many buildings do not comply with seismic actions defined in present-day seismic codes and thus, important post- seismic assessment activities are still to be expected. City-scale resilience, which implies rapid recovery of building functionalities, is undermined by the slowness and qualitative nature of visual inspection (being current practice for post-seismic assessment). A methodology involving model- based interpretation of post-seismic data sources to assess residual capacity of damaged buildings is presented. Vibration measurements and visual inspection outcomes are combined to reduce the uncertainty related to residual capacity. Simplified behaviour models for recurrent building types are used to predict building behaviour during future events. A simulated scenario on a real building stock of a typical Swiss city subjected to moderate seismicity is used for illustration.</p>
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Koh, Hyun-Moo, Kwan-Soon Park, and Junho Song. "Cost-Effectiveness Evaluation of Seismically Isolated Pool Structures Considering Fluid-Structure Interaction." In ASME 2002 Pressure Vessels and Piping Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/pvp2002-1434.

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A procedure for evaluating cost-effectiveness of seismically isolated pool structures is presented. The ground motion is modeled as the spectral density function matching the response spectrum, which is specified in codes in terms of acceleration and site coefficients. Interaction between flexible walls and contained fluid is considered in the form of added mass matrix. The thickness of wall and the stiffness of isolator are used as main design variables while the minimum cost for comparison is estimated. Transfer function vector of the system is derived and spectral analysis method based on random vibration theories is used for calculating probability of failure. Evaluation results of the examples show that the cost-effectiveness of seismically isolated pool structures is relatively high in regions of low to moderate seismicity.
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Ormeni, Rrapo, Serkan Ozturk, Albana Hasimi, Erald Silo, and Elvin Como. "REGION-TIME-MAGNITUDE ANALYSES OF EARTHQAUKE ACTIVITY IN THE ELBASANI GEOTERMAL ZONE, ALBANIA." In 23rd SGEM International Multidisciplinary Scientific GeoConference 2023. STEF92 Technology, 2023. http://dx.doi.org/10.5593/sgem2023/1.1/s05.71.

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A detailed analysis of the b-value within the Elbasani fault zone, Albania, were studied. From instrumental seismicity in this area have been located 1830 seismic events, with magnitude Ml>0.5 Richter. In the zone of Elbasani, hot mineral water (thermal waters) spot out from natural springs which have been known since the 19th century. The statistical properties of seismicity are analysed by using b-value known as Gutenberg- Richter law. The magnitude of completeness (Mc) value is determined as 2.6, and the bvalue is calculated as 1.03 � 0.06, and it is determined that the region has a normal stress level. It is seen that the Mc-value varies from 1.6 to 2.9, the b-value changes between 0.9 and 1.3. The regions with the large b-values (> 1.0) are estimated in the eastern parts of the of Elbasani zone. However, the regions with the low b-values (less than 1.0) are observed in the north, west and southwest of Elbasani zone. The regions with the small b-values correspond to great-magnitude events, whereas the other large values are related to smallmagnitude earthquakes. These results reveal that b-values for all regions are well represented by a b-value typically close to 1.0. There are clear decreasing trends in temporal changes of b-values before the occurrences of some strong main shocks. The lower b-value indicate that there is still moderate stress accumulation in the southwest area of the Llinxha-Kozan thermal water belt. The b-values smaller than 1.0 indicate potential future earthquake area. Following the strong events, there are remarkable decreases in b-value as a function of time. Changes in b-value with time varies in a large band between 0.6 and 1.4. Probabilities of earthquake activity in different magnitude sizes show comparatively great values changing from 50-100 % for earthquakes of 0.5 ? Ml ? 4.5 and the values relatively lower than 90 % for the earthquakes of 5.0 ? Ml. The Elbasani zone has a complex geological structure with a significant number of geothermal water resources and some features of seismicity.

Звіти організацій з теми "Low-To-Moderate seismicity":

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Steudlein, Armin, Besrat Alemu, T. Matthew Evans, Steven Kramer, Jonathan Stewart, Kristin Ulmer, and Katerina Ziotopoulou. PEER Workshop on Liquefaction Susceptibility. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, May 2023. http://dx.doi.org/10.55461/bpsk6314.

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Seismic ground failure potential from liquefaction is generally undertaken in three steps. First, a susceptibility evaluation determines if the soil in a particular layer is in a condition where liquefaction triggering could potentially occur. This is followed by a triggering evaluation to estimate the likelihood of triggering given anticipated seismic demands, environmental conditions pertaining to the soil layer (e.g., its depth relative to the ground water table), and the soil state. For soils where triggering can be anticipated, the final step involves assessments of the potential for ground failure and its impact on infrastructure systems. This workshop was dedicated to the first of these steps, which often plays a critical role in delineating risk for soil deposits with high fines contents and clay-silt-sand mixtures of negligible to moderate plasticity. The workshop was hosted at Oregon State University on September 8-9, 2022 and was attended by 49 participants from the research, practice, and regulatory communities. Through pre-workshop polls, extended abstracts, workshop presentations, and workshop breakout discussions, it was demonstrated that leaders in the liquefaction community do not share a common understanding of the term “susceptibility” as applied to liquefaction problems. The primary distinction between alternate views concerns whether environmental conditions and soil state provide relevant information for a susceptibility evaluation, or if susceptibility is a material characteristic. For example, a clean, dry, dense sand in a region of low seismicity is very unlikely to experience triggering of liquefaction and would be considered not susceptible by adherents of a definition that considers environmental conditions and state. The alternative, and recommended, definition focusing on material susceptibility would consider the material as susceptible and would defer consideration of saturation, state, and loading effects to a separate triggering analysis. This material susceptibility definition has the advantage of maintaining a high degree of independence between the parameters considered in the susceptibility and triggering phases of the ground failure analysis. There exist differences between current methods for assessing material susceptibility – the databases include varying amount of test data, the materials considered are distinct (from different regions) and have been tested using different procedures, and the models can be interpreted as providingdifferent outcomes in some cases. The workshop reached a clear consensus that new procedures are needed that are developed using a new research approach. The recommended approach involves assembling a database of information from sites for which in situ test data are available (borings with samples, CPTs), cyclic test data are available from high-quality specimens, and a range of index tests are available for important layers. It is not necessary that the sites have experienced earthquake shaking for which field performance is known, although such information is of interest where available. A considerable amount of data of this type are available from prior research studies and detailed geotechnical investigations for project sites by leading geotechnical consultants. Once assembled and made available, this data would allow for the development of models to predict the probability of material susceptibility given various independent variables (e.g., in-situ tests indices, laboratory index parameters) and the epistemic uncertainty of the predictions. Such studies should be conducted in an open, transparent manner utilizing a shared database, which is a hallmark of the Next Generation Liquefaction (NGL) project.

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