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Beyza Taskin Atila Sezen Ulgen Mert Tugsal Ayfer Erken 《Bulletin of Earthquake Engineering》2013,11(1):285-312
October 23rd, 2011 M L 6.7 (M w 7.2 KOERI) Tabanli-Van Earthquake caused damage in a widespread area specifically in the settlement regions throughout the Lake Van. A number of 58 buildings totally collapsed during the shake with 52 of them however, reported to be in Ercis district. 17 days after this destructive event, another earthquake of M L 5.6 hit the region again on the 9th of November having the epicentral location at Edremit district. The second earthquake mostly affected the central region of Van province with a number of 25 totally collapsed buildings and furthermore it significantly increased the existing structural damages. Strong motion records from both earthquakes and their impacts on structures as well as geotechnical issues are studied in this paper. Extensive liquefaction triggered lateral spread, landslide and slope failure cases were observed mainly at non-residential areas. Soil amplification is evaluated to be one of the main reasons for the heavy damage occurred in Ercis. Furthermore, site investigations and damage assessment performed after each earthquake proved that the observed damages are strongly correlated with insufficient qualities of structural materials, inadequate detailing and poor workmanship. 相似文献
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Masao Komazawa Hitoshi Morikawa Kajuro Nakamura Junpei Akamatsu Keiichi Nishimura Sumio Sawada Ayfer Erken Akin Onalp 《Soil Dynamics and Earthquake Engineering》2002,22(9-12):829-836
The 1999 Kocaeli earthquake brought serious damage to downtown of Adapazari. To study why strong motions were generated at the town, a bedrock structure was investigated on the basis of Bouguer gravity anomaly, and SPAC and H/V analyses of microseisms. It was revealed that, the basin consists of three narrow depressions of bedrock with very steep edges, extending in E–W or NE–SW directions along the North Anatolia faults, and the depth to bedrock reaches 1000 m or more. Downtown of Adapazari is located 1–2 km apart from the basin-edge. It is considered that, the specific configuration of bedrock amplifies ground motions at the downtown area by focusing of seismic waves and/or interference between incident S-waves and surface-waves secondarily generated at the basin-edge. Studying 3D bedrock structure is an urgent issue for microzoning an urban area in a sedimentary basin. 相似文献
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In this study the effect of cyclic loads on monotonic shear strength has been studied on torsional apparatus. Tests have been conducted on both reconstituted and undisturbed fine-grained hollow soil specimens. The plasticity index of soils is in the range from 2 to 33 for reconstituted specimens, prepared by dry pluviation, and from 5 to 13 for undisturbed soil specimens. The existence of a critical shear strain level, called yield shear strain, where softening starts, is determined from cyclic tests. The level of cyclic yield strain is ± 0.75% for the reconstituted soil specimens and ± 0.5% for the undisturbed soils. If soil undergoes a cyclic shear strain level below the cyclic yield strain, reduction of monotonic strength of reconstituted and undisturbed specimens is limited, but when cyclic shear strain level is larger than yield strain monotonic strength decreases down to 40% of its initial strength. 相似文献
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Commercial linear alkylbenzene sulfonate (LAS), mixture of alkylchain lengths and phenyl position isomers (C10−C13), is widely used as a major constituent of household and industrial detergents in the People's Republic of China. Degradation process and behaviour of LAS compounds during an 82-hour lake water die-away study, with an added LAS concentration of 1.5mg·L−1, was quantified and accomplished by HPLO-UV after extractionon the SepPek C18 reversed-phase cartridges. The degradation rate became progressively faster with increasing chain length. The technique described in this study is fast, sensitive and specific, and can be used to determine low levels of LAS and for establishing water quality criteria and standards relating to LAS and its compounds. Dr. Ayfer Yediler (GSF, National Center for Envirommental Sciences, Ingolstaedter Landstr. 1, D-8042 Neuherberg, FRG) is guest scientist in the Institute of Hydrobiology, Academia. Sinica, Wuhan. 相似文献
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Determination of areas vulnerable to water pollution in river basins helps to generate appropriate water management protection plans. This study aims to define areas vulnerable to pollutants in a data-scarce karstic river basin in Turkey by using a holistic approach integrating the Soil and Water Assessment Tool (SWAT), the DRASTIC framework, and selected isotopes within a decision support system based on a geographic information system to delineate vulnerable areas. DRASTIC was used to show groundwater vulnerability to pollutants. The concentrations of isotopes 18O, 2H, and 3H in groundwater were used to define the vulnerable areas of the karst region. SWAT was utilized to show watershed vulnerability to pollutants in shallow aquifers. The recharge rate parameter in DRASTIC was obtained from SWAT. This methodological approach was applied to the Yuvacık Dam Basin in Kocaeli, part of the Marmara River Basin, as it is a good example of a karstic watershed. According to this study, each approach provides different vulnerabilities when applied separately. The final map obtained from the integrated approach shows that drinking water supplies in the northeast and northwest parts of the basin are highly vulnerable to pollution. All the karst spring catchments and areas near the basin outlet are highly vulnerable. Moreover, across all water samples taken across the basin, those exhibiting the highest concentrations in nitrate were all found in the areas mapped as highly vulnerable. The methodology was validated by analyzing nitrate concentration in 22 groundwater and surface-water samples.
相似文献6.
– Durch Experimente erzielte Anreicherungsfaktoren für Quecksilber in Karpfen bestätigen, daß eine Rüekrechnung von gemessenen Quecksilberkonzentrationen im Fisch auf solche im Wasser mit Hilfe der Faktoren nicht ohne weiteres möglich ist; – dagegen zeichnet sich ab, daß ein Vergleich verschiedener quecksilberhaltiger Fischorgane gewisse Rückschlüsse auf die vorangegangene Art (chronisch oder akut) der Quecksilber-belastung ermöglicht; – die Höhe der Quecksilberaufnahme der Karpfenkiemen bei akut-toxischer Quecksilberkonzentration im Wasser hing von der Queckeilberbelastung der Karpfen ab. Ebenso wurde biervon die Manifestationszeit beeinflußt 相似文献
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Ayfer Yediler ;Xu Ying ;Zhang Yongyuan ;Chen Junjian 《海洋湖沼学报（英文）》1990,8(2):188-196
Commercial linear alkylbenzene sulfonate (LAS), mixture of alkylchain lengths and phenyl position isomers (C10−C13), is widely used as a major constituent of household and industrial detergents in the People's Republic of China. Degradation process and behaviour of LAS compounds during an 82-hour lake water die-away study, with an added LAS concentration of 1.5mg·L−1, was quantified and accomplished by HPLO-UV after extractionon the SepPek C18 reversed-phase cartridges. The degradation rate became progressively faster with increasing chain length. The technique described in this study is fast, sensitive and specific, and can be used to determine low levels of LAS and for establishing water quality criteria and standards relating to LAS and its compounds. 相似文献
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Hydrological models have been widely used for water resources management. Successful application of hydrological models depends on careful calibration and uncertainty analysis. Spatial unit of water balance calculations may differ widely in different models from grids to hydrological response units (HRU). The Soil and Water Assessment Tool (SWAT) software uses HRU as the spatial unit. SWAT simulates hydrological processes at sub-basin level by deriving HRUs by thresholding areas of soil type, land use, and slope combinations. This may ignore some important areas, which may have great impact on hydrological processes in the watershed. In this study, a hierarchical HRU approach was developed in order to increase model performance and reduce computational complexity simultaneously. For hierarchical optimization, HRUs are first divided into two-HRU types and are optimized with respect to some relevant influence parameters. Then, each HRU is further divided into two. Each child HRU inherits the optimum parameter values of the parent HRU as its initial value. This approach decreases the total calibration time while obtaining a better result. The performance of the hierarchical methodology is demonstrated on two basins, namely Sarisu-Eylikler and Namazgah Dam Lake Basins in Turkey. In Sarisu-Eylikler, we obtained good results by a combination of curve number (CN2), soil hydraulic conductivity, and slope for generating HRUs, while in Namazgah use of only CN2 gave better results. 相似文献
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