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61.
Y. Jafarian A. Sadeghi Abdollahi R. Vakili M.H. Baziar 《Soil Dynamics and Earthquake Engineering》2010
Cyclic triaxial tests on reconstituted sand samples are broadly employed in practice while they ignore the inherent characteristics of soil in field condition such as aging, fabric, and prior strain history. Relative state parameter index, ξR, is utilized in a probabilistic framework to adjust the cyclic triaxial resistance ratio of sands at 15 uniform cycles (CRRtx,15) to field condition. A wide-ranging database containing the results of cyclic triaxial tests conducted on reconstituted samples has been compiled to derive a correlation between relative state parameter index (ξR) and triaxial cyclic resistance ratio. The adjustment coefficients proposed by researchers are employed to correct CRRtx,15−ξR relationship for actual field condition. The adjusted CRRtx,15−ξR relationships are applied to a database of field liquefaction case histories composed of both SPT and CPT based data and their performances in field condition are evaluated. It is demonstrated that constant triaxial-to-field adjusting coefficients cannot ever predict conservative results. Logistic regression method is employed to derive a field probabilistic criterion that obtains the likelihood of liquefaction initiation in terms of ξR. The ξR-based boundary curve standing for 20% likelihood of liquefaction initiation is found to be the most conservative limit state boundary to be used in field conditions. Finally, the triaxial and field CRR−ξR relationships are composed and a probabilistic triaxial-to-field adjustment coefficient is proposed in terms of ξR and a given liquefaction probability. It is anticipated that the proposed relationship could reasonably correct the results of cyclic triaxial testing on freshly reconstituted sand samples. 相似文献
62.
AbstractThe sediment yield model of the MUSLE (modified universal soil loss equation) is applied extensively throughout the world, but different performances have been reported of its success relative to measured data. A review of all the available literature is presented to assess the application of the model under different conditions and, ultimately, make a comprehensive judgement on the different aspects to allow readers to adjust their further research. A review of 49 papers showed the variable accuracy of the model, which depends on the manner of calculation and determination of the input and output, and the study time and space scales. There were differences in land use, in correspondence of the physiographic characteristics with those of the original conditions of model development, and even in the experience of researchers in applying the model. The results also show the need to consider the original application of the model, as proposed by its developers, to achieve comparable results.Editor Z.W. KundzewiczCitation Sadeghi, S.H.R., et al., 2014. A review of the application of the MUSLE model worldwide. Hydrological Sciences Journal, 59 (2), 365–375. 相似文献
63.
A. Esmaeili E. Sadeghi 《International Journal of Environmental Science and Technology》2014,11(5):1271-1276
Among all environmental contaminations, industrial oil is one of the major pollutants of soil, water, and air. There are different chemical, physical, and biological methods to remove all types of oil pollutions. One of the common biological methods is to utilize the microorganisms like yeast, fungi or bacteria. Previous studies concerning the biodegradation of an aromatic compound in industrial waste water by Aspergillus niger have been reported. In this study, we tried to identify an oil-derived microorganism and evaluate its efficacy on self-removal of industrial oil. Firstly, the strain of isolated fungus from various bulks of used oil was defined via colonial identification and DNA sequencing. Secondly, bioremoval activity of defined fungus (Penicillium commune) was evaluated using gas chromatography–mass spectrometry. The optimum conditions in biological elimination of oil including the incubation time, pH level of culture, and amount of reagents were determined. In the best condition, a removal rate of 95.4 % was obtained. 相似文献
64.
Abdolvahab Kazemi Abbas Sadeghi Mohammad Hosein Adabi 《Arabian Journal of Geosciences》2014,7(2):655-664
In biostratigraphic studies of the Surgah formation in the Kuh-e-Surgah section, 145 samples were collected. The thickness of the Surgah formation is about 175 m, and it consists mainly of limestone and shale. The lower and upper boundaries of the Surgah formation are Sarvak and Ilam formations, respectively, and they are conformable with sharp lithology. Seventeen species which belong to six genera of planktonic foraminifera and four biozones have been identified in this study. Based on foraminifera assemblages and biozone determinations, the age of the Surgah formation is Late Turonian to Early Late Santonian. This section is correlated with the Tang-e-Gerab section. 相似文献
65.
Natural Resources Research - Fractal/multifractal modeling is a widely used geomathematical approach to capturing different populations in geochemical mapping. The rationale of this methodology is... 相似文献
66.
Geotechnical and Geological Engineering - This is the first study to quantitatively evaluate the local site effects in the most severely affected neighborhoods of Sarpol-e-Zahab city following the... 相似文献