TMMOBABSTRACT: Population of Antalya is growing rapidly due to internal immigration. Moreover, millions of tourists are visiting Antalya every year. Antalya city center lies in the second degree earthquake zone of Turkey. Western part of Antalya, where seismic activity is more intense, lies in the first and second degree zones Taking in to account the poor construction quality and the weak ground conditions, seismicity of Antalya becomes point of interest. In this study, to investigate the seismicity of Antalya city center, a seismic hazard analysis was carried out considering earthquakes occurred between 1900 - 2010 in the seismotectonic zones around Antalya, using statistical techniques. Antalya city center is located in the central part of Isparta angle and affected by earthquakes which are the products of components of this tectonic structure. a parameters lie in the range between 5.61 6.77, and b parameters in 0.86 1.06 for the seismotectonic zones around Antalya. For a circle having radius of 100 km and the centre is located in Antalya city center, probability of occurrence of an earthquake having magnitude 5 or more is 71 %. It is understood that probability of an earthquake having magnitude 6.5 or more is 15 % in 50 years. Applying attenuation relationships, the greatest horizontal ground acceleration is estimated as 0.1g. For soft soils it is obvious that this value will reach a higher value due to ground amplification. It is clear that in a different study, magnification and liquefaction studies should be studied for the weak soils. Before starting an investigation for safety of buildings against earthquake, a micro-zonation study related to dynamic behaviour of all the Antalya soils should be completed.
ABSTRACT: Weathering grades and their depths are some of the most important geo-engineering propertiesdetermining the cost, efficiency and sustainability of the engineering projects. Weathering properties of therocks should be clearly defined during the preliminary surveys of the studies on foundations, slopes etc. Asweathering properties are heterogeneous and anisotropic more boreholes are needed to increase theaccuracy of the interpretations of the subsurface. Electrical Resistivity Tomography (ERT) technique isused for different purposes to obtain faster and more economical data from wider area than drilling. Dueto such specialities of ERT, the technique was used for determining the weathering properties of thepyroxenites and dunites outcropping in Bursa region. ERT studies were carried out in three lines. Two- ofthe lines were on the dunites and the other line on the pyroxenite. Dunites in this study were observed fromunweathered to completely weathered stages, and the pyroxenites were observed from slightly tocompletely weathered stages. During ERT studies both dipole-dipole and Wenner configurations weredeployed. According to the data obtained, inversion model sections were generated. These sections wereevaluated regarding the changes in engineering properties of the dunites and pyroxenites. According to theevaluations, it is concluded that Wenner configuration especially for the dunites represents betterresistivity distributions for the weathering properties.
ABSTRACT: The studies to determine the excavatability properties of rocks contribute to the applicability of theengineering project in terms of the cost of excavation. In this study, excavatability properties of EarlyCarboniferous aged Gümüşhane Granotiod outcropped in the residential area of Gümüşhane were examined. Firstly, four different areas were selected and the rock masses were grouped according to theirdegree of weathering based on the description criteria of ISRM. As a result of these studies, the rockmasses in field-1, field-2 and field-3 were determined as moderately weathered. The weathering degree ofrock mass in field-4 was highly weathered. In the second stage, properties of discontinuities andgeomechanical parameters of intact rock material were determined. In the next stage, RMR89, Q and GSIvalues of rock masses were determined and the rock masses were classified using the excavatabilityclassification systems. Moderately and highly weathered rock masses were classified to be in ripping anddigging categories, respectively. It was determined that the moderately weathered rock masses wereripped by using hydraulic breaker and the highly weathered rock masses were digged by using face shovel.In the final stage, the data obtained from these studies and the excavation works in the selected areas werecompared. According to the results, the excavation methods suggested by Tsiambaos and Saroglou (2009)are completely compatible with in-situ excavation works.
ABSTRACT: In this study, causes of surface deformations observed along the Sarıgöl fault zone have been investigated. Sarıgöl Town is located at the southeastern end of the Gediz Graben. The rocks exposed in the study area, from bottom to top, are metamorphic rocks of Menderes Massif, Plio-Pleistocene aged Asartepe formation and Holocene alluvium. The Asartepe formation is made up of weakly cemented clastic rocks and unconformably overlies the metamorphic rocks. The mapped faults divide the Sarıgöl area in to 3 different blocks. One of the fault passing throughout Sarıgöl municipality exhibits current deformational patterns on irrigational chanells, asphalt roads and cracks on the walls of several houses. The amount of vertical displacement of surface rupture along the fault is about 20-45 cm in the year of 2000. On the other hand, the amount of displacement measured on the same profile in 2010 is 1.00 1.25 m. In this study causes for the additional vertical displacements of 60 85 cm which occurred in ten years were investigated in detail. Sarıgöl fault is defined as Listric normal growth fault in this study. Soil beds in the hanging wall fault pocket are sloped towards the concave-up fault surface. In this pocket, an impermeable CH-type clay level at a depth of 9.0 - 11.5 m from the ground surface is located, and this level is overlaid by the silty and sandy soil beds. Surface water are accumulated in the area of triangular shape which is located on the clay level in front of the fault plane. It is estimated that sandy soils, which back-tilted toward listric fault, have been eroded from the open space of fault by the piping under the effect of water and back-tilting after the raining. Formation of the open space in the fault is explained by the rotational movement on the hanging wall of the fault. In addition, subsidence developed on the hanging wall of the fault due to the problem caused by decrease of the water level and drought in the years between 2000 and 2010 were computed. An extra load of 1.0 t/m2 per meter of the decreasing water level was formed and the normally consolidated soil layers were overconsolidated. Amount of vertical displacement on the surface ruptures along the Sarıgöl fault depending on both seismic activity in the region and overconsolidation was investigated in detail.
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ABSTRACT: This study aims to explore the origin and location of the October 23, 2011 Tabanlı-Van earthquake within active tectonic framework of Van city and its surroundings. Field-based studies have been done just after the Tabanlı-Van earthquake, and then geometry and type of observed deformational structures were evaluated and integrated with the results of previous active tectonic studies in the region. The observedstructures can, based on seismic geomorphological indicators, be grouped in to two main categories: (1) seismotectonic landforms related to tectonic stress, and (2) seismogravitational landforms related to seismic shaking and earths gravity. Seismotectonic landforms are common within a 10-km-long deformation zone located between Van Lake and Erçek Lake. These occurs as N5070°E trending synclines and anticlines, most commonly in the area between Bardakçı and Topaktaş villages. Seismogravitational landforms are common in water-saturated sediments of Lake Van, particularly along its eastern margin; they are mostly liquefaction-induced features and are expressed in the form of lateral spreading, ground subsidence, and mass movement. Reverse fault planes deforming and displacing Upper Pliocene-Pleistocene sediments form the other group of common structures in the region. They trend in N5070°E direction direction and dip at 45-50° to the north; they are oblique structures with sinistral strike-slip components. Similar active faults were mapped by Özkaymak (2003) at three locations to the north of Van city center: north of Beyüzümü village, near the main gate of the Yüzüncü Yıl University Zeve Campus and southern part of the Aşıt village. Evaluation of previously mapped fault segments and recent observations in the deformation zone are consistent with an approximately 10 km wide active thrust fault zone that comprises, at least, five N5070°E striking and north-diping (ca. 47°) fault segments. Kinematics of these faults is consistent with fault plane solutions of 23 October, 2011 Tabanlı-Van earthquake. We suggest that newly formed and/or reactived fault segments in this fault zone were the source of the 23 October, 2011 Tabanlı-Van earthquake. The absence of surface rupture(s) is attributed to the geometry of a blind thrust. According to geological mapping and kinematic analyses, the active tectonics of the region is the manifestation of, in addition to ENE-WSW-striking thrust faulting, NNW-SSE-directed compression as expressed by NE-SW-trending sinistral strike-slip faulting, NW-SE-trending dextral strike-slip faulting and N-S-trending normal faulting