Assessment of SPT-Based Liquefaction Potential of Erbaa (Tokat), Turkey

Turkey is one of the earthquake prone countries in the world. The seismicity of the northern part of Turkey is mainly controlled by active North Anatolian Fault Zone. Several earthquakes and earthquake triggered hazards occurred by the tectonic activity of this fault zone. In recent past, 1999 Adapazari earthquake (Mw=7.4) has caused several fatalities in the western part of this fault zone. One of the most important observations after the earthquake was the liquefaction-related damages of the buildings. In this study, the liquefaction potential of Erbaa (Tokat) settlement area in Turkey, located partly on an alluvial plain of Kelkit river within the North Anatolian Fault Zone has been evaluated. Several boreholes were drilled and laboratory tests were performed on soil samples. Liquefaction analysis was performed by using SPT-based methods suggested by Youd et al. (2001), Cetin et al. (2004), and Idriss and Boulanger (2006). For the analysis, an earthquake magnitude of Mw=7.4 and the different peak ground acceleration (PGA) values were considered. The distribution of the liquefaction potential areas was presented on the maps. Based on the analysis, the loose granular materials of alluvium are likely to liquefy in case of occurrence of large magnitude earthquake with high PGA value

Antique stone quarries in Turkey: a case study on tuffs in the Temple of Apollon Smintheus

All types of stones have been used as building stones, depending on their durability, visual harmony with the intended construction and availability. In the Hellenistic period, as in other periods, tuff was preferred as a building stone due to its convenience – it was easy to extract, transport and use for building. In the present study, three ancient quarries that were the possible tuff sources for the Apollon Smintheus Temple in C¸ anakkale are investigated by comparing the durability properties of stones in the temple and in the quarries. These properties are determined using physical and physico-mechanical tests, comparing fresh and artificially weathered samples. Microstructural and elemental correlations were found using optical microscopy, stereomicroscopy, X-ray diffraction, scanning electron microscopy, methylene blue adsorption and X-ray fluorescence analyses. The results indicate that temple tuffs and two of three quarries have similar geological engineering and microstructural properties with the strong claim that those two quarries could have been the source of building stone for the temple.Peer reviewe

Ground Deformations Observed After 23.10.2011 M\u3csub\u3ew\u3c/sub\u3e 7.2 VAN Earthquake (Turkey)

A destructive earthquake with a moment magnitude of 7.2 occurred in the north of the Van province (Turkey) on 23rd October 2011 at 13:41 local time and caused approximately 600 deaths and more than 4000 injuries. Many damaging aftershocks were recorded for more than a month after the main shock including a triggered earthquake (Mw 5.6) located in the southern district of Van, namely Edremit, on November 9th, 2011 which caused additional damage and casualties. After the Mw 7.2 Van earthquake, earthquake-induced ground deformations such as liquefaction and lateral spreading were extensively observed around the shores of Lake Van and in the floodplains of rivers. The Karasu River floodplain, which is one of the major streams in the region, severely suffered from liquefaction and lateral spreading. In this study, a brief overview of the Mw 7.2 Van earthquake as well as earthquake-induced ground deformations is presented. Then, the results of field reconnaissance on liquefaction and lateral spreading features observed in the Karasu River floodplain are explained. Furthermore, subsurface characteristics of liquefied layers are documented considering the data obtained from a borehole drilled just on top of the sand boil after the earthquake. The borehole data indicate that the liquefaction occurred in a sandy zone with very shallow groundwater level in the Karasu River floodplain

Echocardiography Device Selection with Multicriteria Decision Making Methods

Amaç: Medikal cihazlar hastanelerde en çok bütçe ayrılan kalemlerdendir. Bu nedenle medikal cihaz alım kararı kritik kararlardan biridir. Bu çalışmada, bir devlet hastanesinde Kardiyoloji Servisine alınması planlanan ekokardiyografi cihazı seçim problemi ele alınmıştır. Gereç ve Yöntem: Ekokardiyografi cihazı seçimini etkileyen kriterler ve mevcut alternatif cihazlar konuyla ilgili literatür taranarak ve kardiyoloji alanında uzman üç hekimin görüşleri alınarak belirlenmiştir. Seçim kriterleri belirlendikten sonraAnalitik Hiyerarşi Süreci (AHP) yöntemi ile kriterler ağırlıklandırılmış ve İdeal Çözüme Dayalı Sıralama Tekniği (TOPSIS) yöntemi ile alternatifler sıralanarak en iyi alternatif belirlenmiştir. Bulgular: Ekokardiyografi cihazının seçim problemi için belirlenen alternatiflerin öncelikleri AHP yöntemine göre, B cihazı için %48, ikinci sırada yer alan A cihazı için %29, C cihazı için ise %23 olarak bulunmuştur. TOPSIS yöntemi ile İdeal Uzaklık (Si* ), Negatif İdeal Uzaklık (Si-) ve her bir karar noktasının ideal çözüme göreli yakınlık (Ci*) değerleri B cihazı için sırasıyla 0, 0.124287 ve 1 olarak bulunmuştur. Sonuç: AHP ve TOPSIS yöntemine göre B cihazı birinci alternatif olarak öne çıkmıştırPurpose: Medical devices are the most budgeted items in hospitals. For this reason, the decision to buy a medical device is one of the critical decisions. In this study, the selection problem of echocardiography device planned to be taken to a cardiology department in a public hospital was discussed. Methods: Criteria affecting echocardiography device selection and available alternative devices were determined by reviewing the relevant literature and taking the opinions of three physicians specializing in cardiology. After the selection criteria were determined, the criteria were weighted by the Analytic Hierarchy Process (AHP) method and the best alternative was determined by sorting the alternatives by TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) method. Results: The priorities of the alternatives determined for the selection problem of the echocardiography device were found to be %48 for B, %29 for A, and %23 for C, according to the AHP method. With the TOPSIS method, the ideal distance (Si *), negative ideal distance (Si-) and the ideal solution relative (Ci *) values of each decision point were found to be 0, 0.124287 and 1 for B, respectively. Conclusion: According to the method of AHP and TOPSIS, device B is the first alternativ

Quantification of weathering depths in slightly weathered tuffs

Slightly weathered white and pink tuffs of Midas monument have deterioration problems. In this study, depths of the weathering zones developed in the tuffs are investigated through optical microscopy, XRD, chemical analyses, SEM and some index parameters. By examining quantitative weathering indices and comparing them with thin section studies, it is found that thin section analyses of the phenocrysts; LoI and WPI are good indicators to quantify the depth of weathering for the tuffs. However, thin section studies have limited value for fine-grained tuffaceous matrix: The chemical weathering of the tuffs produces weathered zones that are 4.5 cm thick within the white tuff and 2.5 cm thick within the pink tuff. Physical weathering causes fracturing of feldspars along their cleavage planes. Variations of the index properties of the tuffs caused by weathering are not significant enough to quantify the weathering depths in the tuffs

Erbaa (tokat) Alüvyal Zeminlerine Ait Makaslama Dalgası Hızları (vs) Veri Tabanın Oluşturulması Ve Yerleşim Alanı İçin Zemin Büyütme Değerlerinin Tespiti

Kelkit Çayı'na oldukça yakın bir alanda kurulmuş olan Tokat iline 59 km uzaklıkta bulunan Erbaa ilçesi, aynı zamanda deprem üretme açısından aktif olan Kuzey Anadolu Fay Zonu'nun doğu kısmında yer almaktadır. Erbaa ilçe merkezi Kelkit Çayı'nın güney kısmındaki alüvyal bir zeminde kurulmuştur. Yerleşim yeri, 1942 Erbaa-Niksar (M=7.2) depreminden sonra ilçede meydana gelen hasar nedeni ile farklı bir yere taşınmıştır. Bu çalışmada, Erbaa'nın (Tokat) yer aldığı Kelkit Vadisinde, halen çökelimini sürdürmekte olan alüvyal zeminlerin makaslama dalga hızları (Vs) belirlenecek ve yöreye ait karakteristik bir zemin makaslama dalga hızı dağılım haritasının ortaya konacaktır. Bunun için, inceleme alanında daha önce yapılmış sondaj verileri ve yeni açılacak sondaj kuyularından alınacak veriler kullanılarak, standart penetrasyon deneyi (SPT) bazlı Vs dağılım haritası hazırlanacaktır. Ayrıca, SPT-Vs ilişkisi dikkate alınarak, yöreye ait bir ampirik ilişki de bulunacaktır. Daha sonra, bu analizler sonucunda oluşturulacak haritalar CBS (Coğrafi Bilgi sistemi) ortamına aktarılacaktır. CBS ortamında alana ait haritalar katmanlar halinde hazırlanacak ve gerekli sorgulamalar yapılacaktır. Böylece oluşan harita/haritalar, arazi kullanımına yönelik değerlendirilecektir

Nokta yükleme deneyi ile ilgili uygulamada karşılaşılan problemler

Nokta yükleme, deneyi., iki. konik, uç arasına yerleştirilen kayaç örneğinin 'kırılması esasına dayanmaktadır. Yenilme yükü ve örnek boyutları kullanılarak bulunan nokta yükleme dayanım indeksi çeşitli amaçlarla mühendislik jeolojisi çalışmalarında kullanılmaktadır., Bu makalede, nokta yükleme, deneyi, ile ilgili uygulamada karşılaşılan, aletsel. ve kullanıcıyı ilgilendiren problemler tartışılmıştır. Yazarın uygulamada elde. ettiği, deneyimleri sonucu, standart deney formuna kayacın '"'D'" boyuta, kırılma, zamanı ve yüzde, olarak yenilme yüzeyindeki süreksizliğin ve- kayaç dokusunun kontrolü hakkındaki bilgilerin eklenmesi önerilmiştir., Tek eksenli sıkışma dayanımı (öc ) - nokta yükleme dayanım indeksi (Is^ ) oranının (k) değişik, kayaçlar için çok geniş bir aralıkta değişmesi nedeniyle,, mühendislik projelerinde bu oran ayrıca belirlenmelidir. Bu çalışmada, tüfler için kullanılabilecek yüksek korelasyon katsayısı veren fcT^-fls^o«,) ilişkisi, sunulmuştur.The point load index, test is .based on the principle that rock sample is broken between two conical platens.. Faiiure load and specimen dimensions are used to calculaie the point load strength index and this index is used in engineering geological studies.. In this paper, the problems related to the point load testing device and the common mistakes of the users are discussed. Based- on the experience of the author, a proposal far including "B* " dimension of the rock, failure time, and. textuml and structural information of the failure stiff ace of rock in the point load test form is given, k-value, defining the ratio between the uniaxial compressive strength (s&J and the point load strength index (Js(50))f varies significantly for different rocks. Therefore, k-values for different rocks should be assessed for engineering projects. In this study, a linear relationship with high correlation coefficient between (oc ) and (ls^{rj) is given for tuffs

Formation and deterioration of fairy chimneys of the Kavak tuff in Urgup-Goreme area (Nevsehir-Turkey)

Ph.D. - Doctoral Progra