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ABSTRACT In this study, wavelet transform was used for identifying the locations and boundaries of discontinuities in gravity data. Therefore this method was applied both synthetic models and field data. One and two prism models were used to compare structural effects. In addition, the square root of the sum of the squares of the H, V and D components (HVDM) method and relief shaded maps of wavelet transform results were investigated for comparing the results. A Bouguer gravity data set from eastern part of Turkey is used for field data. The eastern part of Turkey which has major tectonic structures, with the effect of Arabian Plate's northward motion, Anatolian block and Northeastern Anatolian Block escape to west and east, respectively. The study area includes major tectonic elements such as East Anatolian Fault (EAF), Malatya Fault (MF) and Bitlis-Zagros Suture Zone (BZSZ). In synthetic part of our study, the locations and boundaries of one and two prism models were successfully determined with using wavelet transform especially in the results of vertical and horizontal components and also HVDM method. In field study, MF, one of the major tectonic elements in study area, was detected in the result of vertical component; EAF and BZSZ were detected in the result of horizontal component of wavelet transform. The location of same tectonic elements was also observed in the results of the HVDM method and relief shaded map. Presentation Date: Wednesday, October 19, 2016 Start Time: 3:10:00 PM Location: 141 Presentation Type: ORAL
ABSTRACT: Ever since its development, the GSI-Index has attracted interest in the field of rock engineering. In spite of some uncertainties and inadequacies, the GSI-Index has found acceptance for characterizing various types of rock masses. In this study, firstly a quantitative approach was presented to determine the GSI-Index for weak rock masses. Secondly, empirical equations were developed for the estimation of rock-load height and support pressure. Thirdly, the results obtained from the proposed empirical approach were compared with those acquired from closed-form and numerical solutions and a reasonable agreement was obtained. Finally, a new empirical approach that can be used in rock reinforcement design of tunnels excavated in poor and very poor rock masses was briefly presented. The developed design method was applied to the Malatya No: 7 railroad tunnel excavated in squeezing rock condition, miss-aligned due to stress and water effect, as well as having poor support conditions. INTRODUCTION To estimate the support pressure in extremely weak rock mass accurately, it is essential that such rock mass be quantitatively characterized. In the characterization of poor and very poor rock masses, the application of existing GSI indices is hindered by the fact that the use of the index for weak rock mass is to some extent subjective and requires long-term experience [1, 2, 3, 4, 5, and 6]. The method presented in this paper deals with overcoming such inconveniences and uncertainties present in previous methods. In order to better characterize a weak rock mass, two important indicators, namely Broken Structural Domain (BSTR) and Joint Condition Index (Ijc) from Ünal?s M-RMR classification system  have been added to the procedure. Reliable prediction of tunnel support pressure (rock load) is a difficult task in the area of tunnel engineering and has been highly subjective and open to argument. Starting with Terzaghi?s rock load concept , several empirical approaches using rock mass classification systems have been developed for the estimation of tunnel support pressure [9,10,11,12,13,14,15,16]. Among them, Barton?s Q-dependent and Ünal?s RMR-dependent approaches have been widely used. The proposed empirical approach briefly presented in this paper is a sophisticated version of Ünal?s RMR-dependent approach, taking into consideration almost all important factors affecting the amount of rock load. The main advantage of this new approach lies in the fact that it is applicable to overstressed and squeezing rock mass.
SYNOPSIS: After a short description of the Karakaya Power Plant, the results of the geological investigations are summarized in order to permit a good understanding of the extensive stabilization work which was necessary for the protection of both valley flanks and especially of the left one. The selection of the rock properties to be introduced in the analysis is explained on the basis of site observations and laboratory tests. Furthermore, the applied method of computation for the dimensioning of the rock anchors is mentioned and the system implemented is indicated in a general view. RESUME: Après une brève description de l'amenagement hydro-electrique de Karakaya, les rasultats de l'etude geologique sont resumÌs de façon à ce que le lecteur puisse comprendre les travaux importants qui se sont averes necessaires pour la stabilisation des deux flancs rocheux, specialement en ce qui concerne celui sur la rive gauche. Le choix des paramètres est explique sur la base des observations effectuees sur le site et des essais en laboratoire. Mention est faite de la theorie appliquee pour le dimensionnement des ancrages et une vue d'ensemble de leur positionnement est donnee. ZUSAMMENFASSUNG: Nach einer kurzen Beschreibung der Kraftanlage Karakaya werden die Ergebnisse der geologischen Untersuchungen zusammengefaßt, damit der Leser versteht, warum die Stabilisierung der beiden Felsufer, vor allem des linken, so umfangreiche Arbeiten erforderte. Aufgrund der Beobachtungen an Ort und Stelle und der Laboratoriumsversuche wird die Wahl der Berechnungsparameter erlautert. Ebenso wird die angewandte Berechnungsmethode dargelegt, welche der Dimensionierung der Felsanker zu Grunde liegt. Schlußendlich wird ein Überblick ueber die verlegten Spannanker gegeben. 1. INTRODUCTION The engineer dealing with the design of large dams is facing today in an increasing manner major geological problems. The reasons are evident: on one hand the water demand becomes more and more important, on the other hand the favourable dam sites are already used for water storage. Thus there is a real worldwide run on every location where a new storage lake might be created either for irrigation, water supply, power or simply for the flood control and discharge regulation. In several parts of the world, water management is not yet well advanced and many regions do not yet dispose of the necessary water regulation and distribution. Considering the overall growing population numerous countries having used until now their water resources without big concern, begin to be aware of the major difficulties they will incur in the coming decades with respect to the water supply problems. For every dam engineer, it is, therefore, a big challenge not to give-up too easily a dam site even when the geotechnical conditions appear very complex. The modern technics of foundation improvement by means of guniting, grouting and anchoring are a big help for all kinds of stabilization works and it is not seldom that a dam site can be rescued with additional expenditures, perhaps rather high in absolute figures but quite justified in view of the large benefits generated by the development scheme. 2. DESCRIPTION OF KARAKAYA DAM AND POWER PLANT The Karakaya hydro-power scheme is located in Eastern Turkey on the Firat (Euphrates) river, some 170 km downstream of the Keban dam and 75 km East of Malatya. The storage lake is considerably smaller than that of Keban, which achieves also the river regulation for Karakaya. For this paper only the last section is of interest and shall, therefore, be described in more detail. At the Karakaya dam site the narrow river bed is flanked on both sides by generally steep rock walls, alluvial fans or terraces are not available. Tributaries have locally created relatively limited cones of rockfall debris. The superficially weathered metamorphic rocks of the slopes also produce rockfall and talus. The highly metamorphosed formation strikes dominantly west to east and dips northwards at 20° to 40°. Local undulation of the strike direction is due to the lenticular shape of rock bodies which intercalate the isoclinal structure. Several mylonites, generally only some centimeters thick, strike more or less parallel to the general trend of the formation, but the dip is more inclined and, therefore, cuts the strata. At the dam site a complex of hornblende-gneisses and amphibolites having minor intercalations of hornblende-schists is prevailing. The upper portion of the section is built of mica-gneisses and mica-schists which alternate with phyllites. Intercalations of lenticular shaped marble have been observed about 2 km upstream of the site on the eastern bank. Along its boundary with the overlying mica-gneisses, the hornblende-complex shows slight serpentinization. Different possible dam axes have been investigated but the geological most favourable site is in the section within the hornblende rich complex near the Karakaya village. The overlying mica-gneisses are hard and relatively little tectonized, and the contact zone between hornblende-gneisses and mica-gneisses shows only a very thin coat of mylonitic facies.