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Öğe 19th May 2011 Simav (Kutahya) earthquake and response of masonry Halil Aga Mosque(Techno-Press, 2013) Ural, AliThe May 19, 2011 an earthquake hit Simav (Kutahya) province in Turkey. Simav is a district of Kutahya located 255 km southwest from capital city of Turkey. According to Turkish General Directorate of Disaster Affairs (DAD), the magnitude of this moderate earthquake was 5.7. The major percent of the housing stock in the affected region was built in masonry. Many masonry dwellings, mosques and also minarets were heavily damaged due to this seismic activity. The Halil Aga Mosque and its minaret were also heavily damaged as a masonry structure around the earthquake region. In this paper, a site survey of masonry damages is presented and Response Spectrum Analysis of the Halil Aga Mosque is performed using the finite element method.Öğe Architectural and structural analysis of historical buildings: The case of Kırklareli Museum in Türkiye(Techno-Press, 2024) Aksoy, Ercan; Ural, AliTraditional immovable cultural assets are significant in terms of societal memory and cultural continuity. Therefore, it is essential to preserve their original qualities without alteration while also assessing their resilience under various influences. This study aims to document the Kırklareli Museum building and conduct a performance analysis for potential earthquake scenarios. To this end, surveys of the structure were conducted, on-site inspections were carried out, and ground and material properties were determined for use in the analysis. The 3D model of the structure was prepared to understand its behavior during earthquakes. The analysis results indicate that there will be no damage to the structure. However, it should be noted that damage could occur in the event of a more severe earthquake than the design earthquake specified by the regulations. This study is significant not only for encompassing the museum structure but also for providing a comprehensive evaluation by determining all material properties.Öğe Crack development depending on bond design for masonry walls under shear(Techno Press, 2012) Ural, Ali; Do?angün, AdemWalls are the most important vertical load-carrying elements of masonry structures. Their bond designs are different from one country to another. This paper presents the shear effects of some structural bond designs commonly used for masonry walls. Six different bond designs are considered and modeled using finite element procedures under lateral loading to examine the shear behavior of masonry walls. To obtain accurate results, finite element models are assumed in the inelastic region. Crack development patterns for each wall are illustrated on deformed meshes, and the numerical results are compared.Öğe Damages to rubble stone masonry structures during the January 24, 2020, Sivrice (Elazığ) Earthquake in Turkey(Techno-Press, 2022) Ural, Ali; Fırat, Fatih K.; Kara, Mehmet E.; Çelik, Tülin; Tanrıverdi, ŞükranThe earthquake with a magnitude of Mw 6.8, which occurred on January 24, 2020, hit Sivrice (Elazığ) province of Turkey. The earthquake area takes place on the East Anatolian Fault Zone (EAFZ) located between the Arabian and Turkish plates, one of the most active seismic regions in Turkey. According to the Disaster and Emergency Management Presidency of Turkey (AFAD), 584 buildings collapsed, 6845 were heavily damaged, 1207 were moderately damaged, and 14389 were slightly damaged. The authors went to the region of earthquake after the mainshock to investigate the earthquake performances of masonry buildings. This paper presents the seismological aspects of the earthquake, acceleration records, and response spectra with different damping ratios. Furthermore, some typical damages and failure mechanisms on masonry buildings like rubble stone dwellings and minarets are discussed with illustrative photos. Although many major earthquakes have occurred in the region, similar mistakes are still being made in masonry building construction. In consequence, some suggestions viewpoint of the wooden tie beams, the corner details of masonry walls, the door and window openings, the metal fasteners and the earthquake codes are made to be more careful in masonry constructions at the end of the article.Öğe Evaluation of masonry minarets collapsed by a strong wind under uncertainty(Springer, 2015) Ural, Ali; Fırat, Fatih K.A strong wind hit Aksaray province in Turkey on the March 12, 2013. In this natural disaster, two masonry minarets collapsed and one minaret slightly damaged. Fortunately, there was no human injured. In this paper, detailed information about the collapse mechanism of the minarets is given with some illustrative photographs, and a finite element analysis is performed on a collapsed minaret. Here, wind loads that influence on masonry minarets are examined by the use of statistical methods. That is why, the wind speed data are obtained by Turkish State Meteorological Service for Aksaray province. In addition to these data, the other wind load parameters are evaluated in accordance with the published data and knowledge in the international literature. Two analyses are performed on the minaret according to dead loading and wind loading. Some useful information is given about the mistakes during the construction stage of the minarets based on these analyses.Öğe Experimental and numerical study on effectiveness of various tie-rod systems in brick arches(Elsevier, 2016) Ural, Ali; Fırat, Fatih Kürşat; Tuğrulelçi, Şükran; Kara, Mehmet EminArch-type structures have long been used to span large openings. In many historical masonry structures, the stability of the arches or pillars upon which the arches rest has been ensured by wood or iron tension members, commonly called tie-rods. Limited studies in the literature and earthquake reconnaissance reports have already verified the critical role of tie-rods on seismic behavior of arch-type structures. Iron tie-rods in many historic arches are nowadays susceptible to damages due to excessive corrosion. Similarly, strong seismic excitations or large differential foundation settlements may result in severe damage, in the form of buckling or fracturing, on tie-rods of many historic arches. In such cases, the replacement of the damaged tie-rods using a practical, reliable and effective technique is essential to retain the stability of the structure. To the best knowledge of authors, there is no published work in literature on this specific restoration work. The main objective of this study is to investigate both experimentally and numerically the viability, practicality and efficiency of five different replacement techniques proposed for the tie-rods in historic masonry arches. With this aim, six masonry arches, one reference with no tie-rod and five repaired using various tie-rod connection details, were tested under compressive load. Using the actual nonlinear properties of the masonry units and mortar, which are determined as specified by the current national specifications, a numerical study was also conducted using a commercially available structural analysis program and the test results are compared by the numerical results. In this study, the experimental results are presented in comparison with these numerical results and comments on the tie-rods used on the arches are given in consideration of the obtained results. Furthermore, recommendations are offered to solve the problems of tie-rod applications encountered in restoration works.Öğe Gaziantep Nizip Tahtani (leylek) cami yapısal analiz ve değerlendirmesi(Uludağ Üniversitesi, 2021) Ural, Ali; Çelik, TülinKültürel mirasımızın parçası olan tarihi yapıları korumamız ve yaşatmamız gerekmektedir. Bunun için tarihi yapıların davranışının bilinmesi ve analiz edilmesi gerekmektedir. Yapılan çalışmada, Gaziantep’te bulunan 18. yy yapılan Tahtani (Leylek) Caminin yapısal durumu incelenmiştir. Bu cami üzerinde daha önceden güçlendirme çalışmaları yapılmıştır. Yapının mevcut durumu incelendiğinde caminin beden duvarlarında ve tonozlarda bulunan yapısal hasarlar belirlenmiştir. Çalışmada 3 boyutlu sayısal modeli oluşturmak için sonlu elemanlar yöntemini (SEY) esas alan LUSAS yazılımından yararlanılmıştır. Sonlu elemanlar yöntemi ile caminin mevcut durumu (MD) ve restorasyon sonrası durumu (RD) analiz edilmiştir. Çalışmada caminin yapısal hasarlarının nedenleri belirlenerek camide daha önce yapılan restorasyon hatalarının düzeltilmesine yönelik önerilerde bulunulmuştur. Tahtani Camisinin onarım ve güçlendirilmesi için yığma birimlerde meydana gelen hasarlarda yeniden örme uygulaması, beden duvarı derzlerindeki ayrılmalarda enjeksiyon uygulaması, bütün sütunlar arasında da gergi demiri uygulamasının yapılması önerilmiştir.Öğe January 24, 2020 Sivrice Earthquake and the response of the masonry Haci Yusuf Tas (New) mosque(Techno-Press, 2022) Kara, Mehmet E.; Ural, Ali; Kara, Mehmet E.Masonry structures are the most common structural systems that have been used almost all over the world from the earliest ages of history to the present day. These structural systems are often unfavorably affected by natural disasters such as earthquakes. The main reason for this is that they are built without sufficient engineering knowledge. On January 24, 2020, a severe earthquake occurred near the Sivrice District of Elazığ in eastern Turkey. According to the Turkish Directorate of Disaster and Emergency Management (AFAD), the magnitude of the earthquake was 6.8 and the focal depth 8 km. This earthquake caused damage and destruction to the masonry structures used extensively in the region. The Hacı Yusuf Taş (new) mosque in the Malatya city center, located about 64 km from the epicenter of the earthquake, was among the buildings affected by the earthquake. The mosque has smooth cut stone walls and domes made of brick units. The main dome of the structure was severely damaged during the earthquake. In this study, information about the earthquake is first provided, and the damage to the mosque is then interpreted via photographs. In addition, two separate finite element models were produced, where the current state of mosque and solution suggestions are presented, and response spectrum analyses were carried out. According to these analyses and field observations, a buttress system to the main walls of the structure should be constructed in the direction which has little lateral rigidity.Öğe Kubbe yapı formlarının kenet ile güçlendirilmesi(Niğde Ömer Halisdemir Üniversitesi, 2022) Fırat, Fatih Kürşat; Tanrıverdi, Şükran; Ural, Ali; Kara, M. AliTarihi yapılar bulundukları dönemin kültürünü, tarihini, ekonomik ve sosyal özelliklerini, inançlarını, yansıtan yapı türleridir. Bu yapı türleri arasında yer alan kubbeli yapılar, geniş açıklıkları geçmek amacıyla yapılmış eğrisel örtü sistemleridir. Tarihi yapıları gelecek nesillere de aktarabilmek için yapıların korunması ve yapısal davranışlarının iyi bilinmesi gerekmektedir. Bu çalışmada, hasar görmüş kubbe yapı formlarının, kenet ile güçlendirme tekniğini incelemek için deneysel çalışma yapılmıştır. İlk olarak 2 m çapında 1 m yüksekliğinde sekizgen kasnaklı kubbenin düşey yük altındaki davranışı incelenmiştir. Kubbe yük taşıma kapasitesine ulaştığı zaman kubbe üzerinde bazı çatlaklar meydana gelmiştir. Bu hasarlar kenet bağlantı elemanı kullanılarak giderilmiştir. Kenet ile güçlendirilen kubbede, düşey yük altında deneysel olarak incelenmiştir. Referans kubbe ve kenet ile güçlendirilmiş kubbenin deney sonuçları karşılaştırmalı olarak sunulmuştur. Çalışma sonucunda günümüzde kubbe yapı formlarının onarım ve güçlendirilmesinde çok sık kullanılan kenet uygulamalı güçlendirme yönteminin kubbenin taşıma kapasitesini artırmadığı belirlenmiştir.Öğe Masonry building behaviors during the February 6-12, 2017 Ayvacik-Canakkale Earthquakes(Techno Press, 2019) Ural, AliMasonry structures in the rural areas of Turkey often damaged due to moderate and big earthquakes. After every earthquake many scientists made field investigations on the earthquake performance of these structures and gave many useful information on construction techniques. However, the newly constructed masonry buildings are still not suitable for the suggested techniques, and they are still in danger against future earthquakes. Five moderate earthquakes of moment magnitude Mw 5.3, 5.3, 5.2, 5.0, and 5.3 struck the Ayvacik-Canakkale District of Turkey between 6 and 12 February, 2017. More than a thousand of aftershocks were occurred and most of the masonry buildings in the villages nearby main shock epicenter were affected. The author went to the earthquake field and investigated the earthquake performances of masonry structures. This paper presents the recorded acceleration data, acceleration response spectra, and the seismological aspects of these earthquakes. Besides, case studies of damaged stone masonry buildings, and failure mechanisms are discussed with illustrated photos which were taken during the field investigations. It is concluded that the damaged masonry buildings were not designed and constructed properly in accordance with the Turkish building codes or similar specifications.Öğe Response evaluation of historical crooked minaret under wind and earthquake loadings(TECHNO-PRESS, 2013) Ural, Ali; Do?angün, Adem; Meraki, ŞakirTurkey has been hosted various civilizations throughout centuries and it has become one of the oldest settlements all over the world due to the geographical location. Therefore, it has accommodated innumerable historical structures remain from the past civilizations. Protection and conservation of these historical constructions should be the major points for continuity of history. Crooked minaret is one of between these historical invaluable structures. It is located at the city of Aksaray and it dates back approximately 800 years. The minaret has lost its vertical position in time and bends on the North-West direction. In this study, general information is given about minarets and some restoration recommendations are given for crooked minaret based on performed some finite element structural analyses. These analyses are considered into three cases; 1-Dead loading, 2-Wind loading, and 3-Earthquake loadings. Results from the analyses are discussed detailed and some useful recommendations are given in the end of the study.Öğe Seismic behavior of historical inclined minarets under near and far fault ground motions(Taylor & Francis, 2021) Türker, Temel; Demirtaş, Betül; Ural, Ali; Kömür, Mehmet AydınThis study investigates the effects of near- and far-fault ground motion on the seismic behavior of historically inclined minarets. Inclined minarets built in Aksaray and Sivas, Turkey, are selected as numerical applications. The top of the Aksaray and Sivas minarets is 1.30 m and 1.23 out-of-plumb and the inclination values are 2.45 degrees and 1.97 degrees, respectively. Firstly, 3D finite element models of the minarets are created using solid elements by SAP2000 software and the numerical dynamic characteristics are determined numerically. 1992 Erzincan and 1999 Kocaeli earthquakes as near- and far-fault ground motion records are selected for the analyses. Maximum displacements, base bending moments, base shear forces, and principal stresses are determined using the finite element method. The results obtained for both earthquakes are compared with each other. It is clearly seen that near-fault ground motion has resulted in much larger response values for both minaret models when compared with far-fault ground motion and max stresses that occurred on the transition segments.Öğe Seismic performance of masonry buildings during the 2007 Bala, Turkey earthquakes(SPRINGER, 2012) Ural, Ali; Do?angün, Adem; Sezen, Halil; Angın, ZekaiA field investigation was conducted near the town of Bala after two strong earthquakes struck the region on December 20 and 27, 2007. The main objectives of this study are to present the results of the field investigation and examine the characteristics of the recorded ground motions and the corresponding response spectra. The focus of the research was on the causes of damage and failures commonly observed in masonry structures. This study classifies single family masonry dwellings in rural areas and investigates the seismic damage in unreinforced masonry structures. Turkish Earthquake Code requirements for masonry buildings are summarized and compared with the field observations. Our field investigation showed that there has been lack of quality control and regulation for the masonry construction. Diagonal shear cracking and out-of-plane failure were the two major factors that contributed to widespread damage in masonry structures.Öğe Shear tests on stone masonry walls with metal connectors(TAYLOR & FRANCIS LTD, 2014) Ural, Ali; Uslu, SuatMany strengthening techniques for masonry structures have been thoroughly investigated in various studies. Nevertheless, there is still a lack of information on the shear effects of metal connectors used in historical masonry structures. This paper presents the investigation of the effectiveness of metal connectors in relation to the shear collapse mechanism of stone masonry walls. A series of 12 stone masonry walls with metal connectors and an unreinforced masonry reference wall were subjected to shear forces. The test parameters were the length and number of clamps (horizontal metal connectors), and number of dowels (vertical metal connectors). The performance of the different metal connector configurations was compared in terms of strength and mechanism of failure. The results clearly show the effectiveness of metal connectors on shear behaviour of stone masonry walls.Öğe Tek şerefeli yığma minarelerin deprem davranışı ve dinamik analizi(Aksaray Üniversitesi, 2018) Ural, Ali; Çelik, TülinMinareler, Müslümanları namaza çağırmak için İslam dininin ibadet yeri olan camilere bitişik olarak inşa edilmiştir. Türkiye’de ve diğer Müslüman ülkelerde yığma minarelerin büyük çoğunluğu orta şiddetli bir deprem ya da hafif şiddetli bir rüzgâr etkisiyle zarar görebilmektedir. Bunun nedenlerinden biri bu yapıların ince ve uzun olmasıdır. Bir diğer sebebi ise özellikle günümüzde inşa edilen minarelerin herhangi bir mühendislik bilgisi olmadan yapılmasıdır. Bu çalışmada, Aksaray il merkezinde yer alan tek şerefeli 7 adet yığma minarenin deprem davranışları incelenmiştir. Bahsedilen minarelerin geometrik ölçümleri fotogrametrik cihazlar kullanılarak yapılmıştır. Sonlu Elemanlar Metodunu kullanan LUSAS programı ile minareler modellenerek deprem analizleri yapılmıştır. Yapısal analizler birbirleriyle karşılaştırılarak elde edilen sonuçlar yorumlanmıştır.Öğe Triplet tests and numerical validations of stone masonry with dowels under shear(Springer Science and Business Media Deutschland GmbH, 2021) Ural, AliDowels are connected to two masonry units in the vertical direction for the continuity and integrity of walls. According to the national and international literature, studies investigating the effectiveness of dowels on masonry walls are rare. This paper presents a preliminary experimental study performed on tuff stone masonry specimens with dowels to assess the effects of dowels on the shear capacity of masonry walls. For this aim, 54 masonry specimens, nine being controls without dowels and 45 with different dowel diameters and axial load levels, were tested under triplet test procedures, according to TS EN 1052-3 regulations. Numerical validations were performed using the LUSAS finite element software package. The experimental results were compared with numerical simulations. The present study reveals that dowels significantly improve the shear capacity of masonry walls. Furthermore, recommendations regarding suitable dowel ratios are made.Öğe Yığma yapılarda kullanılan kenetlerin yapı davranışına etkilerinin incelenmesi(Afyon Kocatepe Üniversitesi, 2021) Çelik, Tülin; Tanrıverdi, Şükran; Ural, Ali; Fırat, Fatih KürşatKültürel mirasımızın önemli bir parçası olan tarihi yapılar, zaman içerisinde iklim şartları ve insan etkilerinden kaynaklanan yapısal bozulma, hasar ve yıkılmalara maruz kalmıştır. Tarihi yapıların yapısal bütünlüklerini koruyarak gelecek nesillere güvenli bir şekilde aktarmak temel amaçlarımız arasında yer almalıdır. Tarihi yapıların onarım ve güçlendirilmesinde aslına uygun malzeme ve uygun onarım ve güçlendirme teknikleri kullanılması gerekmektedir. Tarihi yapılarda en yaygın kullanılan onarım ve güçlendirme yöntemi kenet ve zıvanalardır. Yapılan çalışmada, kenetlerin batma noktasının taşın kenarına olan mesafesi dikkate alınmış ve kenetlerin taşın kayma dayanımı üzerindeki etkisi deneysel ve sayısal olarak incelenmiştir. Bu kapsamda deneysel çalışma laboratuvarda gerçekleştirilmiş olup sayısal çalışmada 3 boyutlu modeli oluşturmak için sonlu elemanlar yöntemini (SEY) esas alan LUSAS yazılımı kullanılmıştır. Yapılan deney ve analiz sonuçlarına göre, taş kenarı ile batma noktası arasındaki mesafe incelenmiş ve bunların taşlar üzerindeki etkileri karşılaştırılarak incelenip, birtakım önerilerde bulunulmuştur.
