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WOS: 000390459400009, Soil classification is one of the most important stages in preliminary studies for design applications in geotechnical engineering. The classification of fine-grained soils is mostly determined using Casagrande's plasticity chart. However, owing to the factors affecting determination of liquid and plastic limits, uncertainties can arise in fine-grained soil classification when using this approach. The uncertainty increases particularly when the points on the chart fall on the lines that separate certain soil classes (A-line and/or 50% liquid limit line) or very close to these lines. In this study, a fuzzy classification routine is proposed to minimize these uncertainties. For this purpose, the spatial distances of the evaluation points on the chart from the lines were used as a controlling unit. The membership degrees that define the fuzzified soil (clay and/or silt), and plasticity (low and/or high plasticity), were evaluated by considering sigmoid functions. As a consequence, the soil types were established by aggregating fuzzified soil and plasticity using the fuzzy operators.

WOS: 000323401000001, The Analytical Hierarchy Process (AHP) is a classic and powerful decision support tool. However, the conventional AHP has some disadvantages originating in the expert decision-making process. To minimize the disadvantages of the conventional AHP, a modified analytical hierarchy process (M-AHP), is suggested in this study. This study is conducted in three stages: (i) the theoretical background for the conventional AHP is introduced, (ii) essentials for the proposed M-AHP technique are given with an example solution for the evaluation of snow avalanche source susceptibility, and (iii) a computer code named M-AHP is presented. By applying the methodology suggested in this study, the consistency ratio value for the comparison matrix and the weight vector never exceeds 0.10. The M-AHP program is a complementary tool for natural hazard, natural resource, or nature preservation researchers who apply the M-AHP technique to their decision support problem. (C) 2013 Elsevier Ltd. All rights reserved.

WOS: 000320353500002, The main purpose of this study is to evaluate the geo-mechanical properties of very weak and weak rock materials by using ultrasonic pulse velocity measurements and considering specifically detailed mineralogical compositions. For the purpose, P-wave velocity (V-p) measurements of 66 core samples of the sedimentary rocks including claystones and mudstones collected from Firuzkoy area of Istanbul (Turkey) were carried out. Unconfined Compressive Strength (UCS) tests were then conducted. The axial deformations recorded during the UCS tests were also evaluated and the elastic moduli of the rock materials (E-i) were calculated. Statistical relations were investigated between the values of P-wave velocity measurements and the UCS and E-i. In order to evaluate the effects of detailed mineralogical compositions on the prediction performances of the empirical equations V-p-UCS and V-p-E-i, the reflectance spectroscopy was introduced. 1035 spectral measurements were taken from smooth and fresh surfaces of the failed core samples. Different genetic rock types were defined according to crystal field effect and charge transfer absorptions of transition elements, and water and OH vibrational spectral diagnostics. The statistical relations were reinvestigated, and the individual empirical equations were reproduced for each genetic rock type. The mean values of the multiple coefficients of correlations (R) were obtained to be 0.904 and 0.916 for the equations of V-p-UCS and V-p-E-i. Considering the maximum values of R, the increment rates for the values of the explained variances reach up to 14.3% and 13.5% for the equations, respectively. Additionally, according to the results of the analysis of variance (ANOVA) evaluations, the empirical equations of V-p-UCS and V-p-E-i reproduced for each genetic rock type were found to be statistically significant at the significance level of 0.05. As a consequence, the non-destructive techniques V-p measurements and reflectance spectroscopy could be efficiently used together for the evaluation of the geo-mechanical properties of very weak and weak rock materials in particular. (c) 2013 Elsevier B.V. All rights reserved., Hacettepe University Scientific Research Unit Ankara, Turkey [07 01 602 001], The core samples were provided by the Hacettepe University Scientific Research Unit Ankara, Turkey with the project 07 01 602 001, and used with the permission of the project leader Prof. Dr. Candan Gokceoglu. The author also would like to gratefully thank to Mr. Murat Koruyucu and Dr. Engin O. Sumer for providing necessary conditions in order to implement spectroscopic measurements and XRD analyses.

WOS: 000323204700005, Particularly in the last decade, landslide susceptibility and hazard maps have been used for urban planning and site selection of infrastructures. Most of the procedures for preparing of landslide susceptibility maps need high-quality landslide inventory map. Although the rainfall and seismic activities are accepted as triggering factor for landslides, designation of the triggering factor for each landslide in the inventory is almost impossible when well-documented records are unavailable. Therefore, during preparation of landslide susceptibility map, whole landslide records in the inventory map are used together without classifying based on the triggering factors. Although seismic activity is accepted as a triggering factor, possible effect of the use of seismic activity on production of landslide susceptibility map was investigated in this study, and the subject is open to discussion. For this purpose, a series of stability analyses based on circular failure and infinite slope model were performed considering different pseudostatic conditions. The results of analyses show that gentle slopes have higher susceptibility to failure than steeper ones, even if their stability conditions (susceptibilities) are similar for static condition. The seismic forces acting on failure surfaces may not be sufficiently taken into consideration in the conventionally prepared landslide susceptibility maps. Employing the general decreasing trend in stability condition based on slope face angle and the seismic acceleration, a new procedure was introduced for preparing of the landslide susceptibility map for a scenario earthquake. The prediction performance of occurring landslides increased after the procedure was applied to the conventionally prepared landslide susceptibility map. According to the threshold independent spatial performance analyses of the proposed methodology and the produced landslide susceptibility maps, the area under ROC curve values were calculated as 0.801, 0.933, and 0.947 for the maps prepared by considering conventional method and scenario earthquakes having M (w) values of 5.5 and 7.5, respectively.

WOS: 000288802500012, The Cappadocia region has unique geomorphological features resulting from differential erosional processes which make it very attractive to tourists. Besides the fairy chimneys for which the area is best known, there are also impressive buttes and mesas. Buttes and mesas are formed in regions having flat-lying strata in which the uppermost levels are composed of well-cemented limestones and granular ignimbrites, whereas the lower parts and slopes consist of low-durability tuff and ignimbrites. This durability difference results in serious rockfall events. This study involves two-dimensional rockfall analyses in and near the Avanos, Zelve, and Cavusini areas, where volcano-sedimentary units of Neogene age outcrop, to provide a rockfall hazard map in which areas of tourism activity are also considered.