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Öğe 2023 Kahramanmaraş Depremleri Sonucu Hasar Gören 11 Katlı Betonarme Bir Yapının Deprem Performansının Değerlendirilmesi(2025) Ozmen, Alper; Ekıncı, Enes6 Şubat 2023 tarihinde meydana gelen Kahramanmaraş depremleri ülkemizde bulunan mevcut yapı stokumuzun deprem güvenliği açısından incelenmesi gerektiğini gözler önüne sermiştir. Bu çalışmada 11 katlı betonarme bir yapının 2018 Deprem Yönetmeliğine göre deprem performans analizi aşamaları detayları gösterilmiş ve yapının deprem performansı elde edilmiştir. 2018 Türkiye Bina Deprem Yönetmeliği’nde verilen esaslara uygun olarak gerçekleştirilen performans analizi sonucunda, çalışma kapsamında incelenen yapı her ne kadar kontrollü hasar performans hedefini sağlamış olsa da yapılan saha incelemesinde, yapının bazı taşıyıcı sistem elemanlarında hasarlar gözlemlenmiştir. Bu durum yapı tasarımı aşaması ile proje aplikasyonunun arasında bulunan birtakım uyumsuzluk, hata ve kusurların yapının deprem performansı üzerinde oldukça önemli etkileri olduğunu göstermiştir. Sahada yapılan mevcut durum incelemesi ve performans analizi sonucunda elde edilen bulgular, yapı tasarımı ile ilgili birtakım önerileri de bünyesinde barındıracak şekilde detaylı bir şekilde açıklanmıştır.Öğe 3D Soil Structure Interaction Effects on the Seismic Behavior of Single Span Historical Masonry Bridge(Springer, 2023) Ozmen, Alper; Sayin, ErkutHistorical masonry bridges are cultural heritage of countries and must be protected from destructive effects of nature such as earthquakes, floods, and fires. The interaction of soil and structure has a significant impact on the seismic behavior of masonry bridges. In this study, the effect of Soil-Structure Interaction (SSI) was investigated on a single-span masonry bridge using non-linear time-history analysis. A SSI model of the Velipalas masonry bridge and soil layer was created using 3D solid elements in DIANA software. The nonlinear behavior of the masonry units and soil layer was modeled using the total strain-based crack model and Mohr-Coulomb failure criteria. The earthquakes of 1992 Erzincan, 2003 Bingol, and 2020 Sivrice were used for earthquake excitation. Results showed that considering SSI increased the periods, displacements, velocities, and principal stresses, but reduced the frequency and acceleration values. Hence, the results indicate that SSI effects are significant for the seismic response of single-span masonry bridges.Öğe 6 Şubat 2023 Kahramanmaraş Depremleri Sonrasında Betonarme Kolonlarda Enine Donatı Kusurlarının İncelenmesi(2024) Sayın, Erkut; Ozmen, Alper; Taş, Ömer Faruk; Atar, Muhammed; İnce, OzanTürkiye’de bulunan bina stokunun büyük kısmını betonarme binalar oluşturmaktadır. Yıkıcı depremlerin yaşandığı Türkiye’de betonarme binaların hasar almasında beton kalitesinin düşük olması, donatı detaylarındaki hatalar, statik tasarım hataları ve zemin özelliklerinin iyi belirlenememesi gibi nedenler etkendir. Bu çalışma kapsamında 6 Şubat 2023 Kahramanmaraş depremleri sonrasında Malatya ilinde deprem kaynaklı hasar incelemeleri yapılmıştır. Enine donatı kusurlarından kaynaklı oluşan hasarlar incelenmiştir. İncelenen betonarme yapılarda tespit edilen enine donatı aralıklarının yetersiz olması, kolon kiriş birleşim bölgelerinde enine donatı kullanılmaması veya yetersiz kullanılması, enine donatı kanca boylarının yetersiz olması ve kanca boyu açısının 135o yerine 90o olması ve çiroz kullanılmaması gibi uygulama hataları görseller ile verilmiştir. Ayrıca incelenen enine donatı uygulamalarının Türkiye Deprem Yönetmeliklerinde bulunan enine donatı kuralları ile uygunlukları değerlendirilmiştir.Öğe Assessments of Masonry Buildings and Historical Structures during the 2020 Sivrice-Elaz?? Earthquake(Budapest Univ Technology Economics, 2023) Ozmen, Alper; Maras, Muslum Murat; Ayaz, Yasar; Sayin, ErkutTurkey is located on a seismically active region. The active fault zones, primarily the North Anatolian Fault and East Anatolian Fault, constitute a center to the movements. On 24 January 2020 at local time 20:55, an earthquake of Mw = 6.8 struck Sivrice, Elazig located in eastern part of Turkey. After this main shock, 1185 aftershocks were recorded until February 8, 2020. The main event resulted in 41 human casualties and 1632 injured. Also, 45 people were salvaged from the debris. The earthquake mostly affected to Elazig and Malatya provinces. 633 buildings were demolished, 10492 buildings were severely damaged, 2161 buildings were moderately damaged, and 16046 buildings were slightly damaged in the affected region. This paper focus on evaluating the damages and failures of masonry, adobe, and historical structures in the affected areas around Elazig and Malatya provinces.Öğe Damage propagation and failure mechanism of single dome historical Masonry Mosque after February 6, 2023, Kahramanmaras,earthquake doublets (Mw = 7.7 and Mw = 7.6)(Elsevier Science Inc, 2024) Onat, Onur; Ozmen, Alper; Ozdemir, Engin; Sayin, ErkutMany historical masonry mosques and minarets, including Milky Minaret Mosque and Ulu Mosque, which are very close to Ak Minaret Mosque in Malatya, suffered severe damage and collapsed after the Kahramanmaras, , earthquake on February 6, 2023. Despite the settled loose soil properties and the presence of a small stream flow near the mosque, Ak Minaret Mosque, a historical masonry mosque with a single dome and square, remains operational even after the aforementioned earthquakes. Additionally, DEMA's strong ground motion station was out of service during both earthquakes. This situation raises questions about the mosque's ability to withstand the seismic load. The basic purpose of this paper is to investigate in detail the seismic performance, damage limits, the reason for unexpectedly less damage due to the earthquakes, the potential failure mode, and possible resisted earthquake loads of the historical Ak Minaret Mosque in Malatya, T & uuml;rkiye. To achieve this goal, first, dynamic identification was performed on the mosque one year prior to the aforementioned earthquakes. Next, the material properties were determined using both non-destructive and destructive testing methods. Following the dynamic identification, a numerical model was generated by 3-D solid elements, and this 3-D model was calibrated using the dynamic identification tests. The mosque underwent both nonlinear static and nonlinear dynamic analyses. Nine seismic records were selected for the nonlinear dynamic analysis. Five of them were national, including even Kahramanmaras, , earthquake records, and three of them were selected from an international database on the basis of fault characteristics and site classification. The analysis results indicate that Ak Minaret Mosque incurred less damage than expected during the Kahramanmaras, , earthquakes. This could be due to soil improvement prior to the construction of Ak Minaret Mosque in 1573. Moreover, the effective restoration increased stiffness and maintained the mosque's stability. Finally, the possible resisted PGA by the mosque was around 0.22 g.Öğe Different Soil-Structure Interaction Modelling Strategies for Seismic Analysis of a Masonry Church(Taylor & Francis Inc, 2024) Ozmen, Alper; Sayin, ErkutMasonry structures can be damaged different external reasons such as war, flood, earthquake etc. For protecting and transfer to the next generations, these structures can be examined detailed. Finite element analysis has generally been used for the seismic evaluation of masonry structures. The fixed base assumption has been used in traditional finite element analysis of masonry structures. Interacting with the surrounding soil and structure was generally ignored. The seismic behavior of masonry structures is significantly influenced by the soil-structure interaction (SSI). There are various soil structure interaction modelling strategies in the recent studies. In this paper, the dimensions, mechanical properties and material model of the soil are considered constant. One of them had no soil-structure interaction. The others, roller support case, fixed support case, absorbing boundary case, free field columns and Winkler supports. Variations in the seismic response of a historical masonry church were investigated using 4 different SSI models and a fixed base (SSI ignored) model. Nonlinear time history analyses were employed for the finite element analysis. The soil borehole provided the material characteristics of the surrounding soil. According to the analysis results, higher response amplitudes were obtained when SSI was considered.Öğe Evaluation of material properties of cultural heritage building by destructive and non- destructive testing: Malatya Tas,horan Church case study(Elsevier Sci Ltd, 2023) Ozmen, Alper; Sayin, ErkutHistorical masonry structures are an essential component of cultural heritage. These structures may transfer the lifestyle of previous civilizations to next generations. In order to prevent earthquake damage to these structures, it is important to obtain accurate information on their material properties for reliable computational modelling and strengthening intervention programs. In this context, Destructive Techniques (DT) and Non-Destructive Techniques (NDT) were used together and the results obtained were compared. Tas,horan Church located in Malatya, Turkey was selected as a case study. The aim of this study is to compare the obtained results of Destructive Techniques (DT) and Non-Destructive Techniques (NDT) used to evaluate the original and restoration stones of Tas,horan Church in Malatya, Turkey. The tests conducted include uniaxial compressive strength, flexural strength, water absorption, density, porosity, XRD, SEM-EDX and ageing tests with different solutions (5% H2SO4, 5% HCl and %14 Na2SO4). In addition, NDT methods such as Schmidt hardness, ultrasonic pulse velocity and infrared thermography were used to determine dynamic Poisson's ratio, dynamic modulus of elasticity and UCS. NDT and DT values of the original and restoration stones were presented.Öğe Experimental and numerical analysis of shear behaviour at the interface geopolymer mortar and sand(Nature Portfolio, 2026) Bayindir, Furkan; Ekinci, Enes; Sarici, Talha; Ozmen, AlperThis study aimed to examine the impact of various production parameters on the shear performance at the interface between geopolymer mortar (GPM) and sand soil. Initially, the effects of varying NaOH concentrations (5, 10 and 15 M), aggregate types (stream aggregates (SA), crushed stone aggregates (CS) and construction and demolition waste (CDW) aggregates) and alkali/binder ratios (0.5 and 0.6) on GBFS-based GPM specimens were investigated. For this purpose, compressive strength, water absorption and ultrasonic pulse velocity (UPV) tests were carried out on GPM samples cured for 28 days. The maximum 28-day compressive strength (43.6 MPa) and the minimum water absorption (3.78%) were observed in GPM specimens activated with 15 M NaOH, produced with CS, water-cured and cast at an alkali/binder ratio of 0.5. Experimental findings revealed that the effects of aggregate type on high mechanical and low permeability properties were graded as CS > SA > CDW. Additionally, UPV test results showed positive correlation with compressive strength and water absorption values. Subsequently, the shear performance between GPM and sand soil were determined by using shear box test. In direct shear experiments, decreasing the alkali/binder ratio from 0.6 to 0.5 and the usage of CS increased the sand-GPM friction angle. Moreover, numerical modelling was employed to analysed soil-GPM interaction using the finite element method (FEM) in ABAQUS. FEM results showed that the obtained numerical findings demonstrated strong consistency with experimental data, capturing force-displacement trends therefore the numerical model can be used for parametric studies.Öğe Farklı Depremler Altında Yığma Minarelerin Sismik Değerlendirmesi(2024) Sayın, Erkut; Ozmen, Alper; Eronat, Şule SekinMinareler, camilerin önemli yapı elemanları olup ince ve uzun yapılardır. Tarihi minarelerin çoğu yığma malzeme (tuğla veya taş üniteler) ile inşa edilirken, modern minarelerde genellikle betonarme kullanır. Son depremler, bu yapıların çoğunluğunun, çatlaklardan tamamen göçmeye kadar çeşitli yapısal hasarlara yol açan sismik hareketlere karşı oldukça duyarlı olduğunu göstermiştir. Bu çalışmada, temsili bir yığma minarenin sismik davranışı, 1999 Kocaeli, 2003 Bingöl ve 2011 Van depremlerinin ivme kayıtları kullanılarak incelenmiştir. Kullanılan tüm ivme kayıtları minarenin konumuna göre ölçeklendirilmiştir. Bu amaçla Elazığ şehir merkezinde inşa edildiği düşünülen temsili bir yığma minare dikkate alınmıştır. Sismik analizin ardından minare üzerinde elde edilen deplasman ve gerilme değerleri elde edilmiştir. Minare yüksekliği boyunca yer değiştirmelerin arttığı görülmüştür. Ayrıca geçmiş depremlerdeki hasar bölgelerine benzer şekilde minarenin silindirik gövdesi ile geçiş bölümü arasında maksimum ve minimum gerilme değerleri elde edilmiştir.Öğe Performance evaluation and damage assessment of historical Yusuf Ziya Pasha Mosque after February 6, 2023 Kahramanmaras earthquakes(Elsevier Science Inc, 2023) Onat, Onur; Deniz, Faruk; Ozmen, Alper; Ozdemir, Engin; Sayin, ErkutHistorical masonry heritages are severely affected by the February 6, 2023, Kahramanmaras, earthquakes. The recorded earthquake peak ground accelerations (PGA) are 2.05 g and 0.67 g for Pazarcik and Elbistan earth-quakes at the epicenter, respectively. However, there is not any recorded PGA data related to Kahramanmaras, earthquakes in Malatya. At this point, the current study aims to propose a methodology to estimate the possible resisted load of historical Yusuf Pasha Mosque in Malatya and possible PGA for Malatya by assessing the per-formance located in Malatya city center, which is far from the epicenter of Pazarcik earthquake, which is 162 km, and Elbistan earthquake, which is 100 km, using propagated cracks. After these earthquakes, local damages were registered at the Yusuf Ziya Pasha Mosque. The main prayer hall of the mosque and a tomb were constructed in 1792. Three types of materials were used for the mosque: riyolit tuff, sandy tuff for walls, and timber for the roof. The dimensions of the main hall of the mosque are 17.50 m x 12.53 m. Additionally, there is a small tomb located adjacent to the mosque with dimensions of 7.61 m by 4.46 m. First of all, dynamic identification is conducted, and then a numerical model is generated. Material properties were calculated using non-destructive testing methods. The mosque and the tomb are modeled together. The numerical model is calibrated on the basis of the extracted dynamic parameters. Then, nonlinear time history analyses were performed on the model using eight earthquake records. Three of the used seismic records were international, namely the 1995 Kobe, 1986 Chalfant Valley, and 2010 New Zelland Darfield earthquakes. In addition, five national earthquake records are used for the nonlinear dynamic analyses, namely the 2003 Bingo center dot l, 2011 Van-Ercis,, 2020 Elazig-Sivrice, 2023 Kahramanmaras, Pazarcik, and Elbistan earthquakes. Related graphs were tabulated, and crack propagations of the numerical model were compared to damaged mosques.Öğe Seismic Assessment of the Historical Sutlu Minaret Mosque(Budapest Univ Technology Economics, 2022) Maras, Muslum Murat; Ozmen, Alper; Sayin, Erkut; Ayaz, YasarHistorical masonry structures that connecting the past to the present have great importance because they represent the experiences and characteristics of various cultures. Therefore, the protection of historical structures is important. In this study, the structural response of the historical masonry Mosque was evaluated through dynamic analyses. For this purpose, the Sutlu Minaret Mosque which is located in Malatya, Turkey, was investigated. The three-dimensional model of the historical mosque was generated with ANSYS software. The material properties of the mosque were obtained with experimental tests. The time history analyses were used to obtain the seismic behavior of masonry mosque. In the time history analyses, six different strong ground motion records, including the 2020 Elazig earthquake, were used. After the analysis, displacement and stress values in the mosque were given. The absolute peak displacement value among these earthquake records was obtained from the 1999 Duzce earthquake and the highest principal compressive and tensile stress values were determined for the 2010 Darfield earthquake. Also, the crack regions which occurred in the mosque after the 2020 Elazig earthquake were compared with the dynamic analysis result of the 2020 Elazig earthquake. The crack regions formed after the Elazig earthquake are similar to the possible crack regions formed after the dynamic analysis.Öğe Seismic performance assessment of structures in Malatya Province after 6 February 2023 Turkey earthquake sequences(Springer, 2025) Ozmen, Alper; Ince, Ozan; Tas, Omer Faruk; Atar, Muhammed; Ozbulut, Osman E.; Sayin, ErkutOn February 6, 2023, at 04:17 and 13:24 local time, two major earthquakes struck Pazarc & imath;k and Elbistan districts of Kahramanmara & scedil;, Turkey. The first earthquake had a moment magnitude of the Mw = 7.7 at a depth of 8.6 km, while the second earthquake had a magnitude of the Mw = 7.6 at a depth of 7 km. The earthquakes impacted eleven cities in Turkey, with a combined population of approximately 15 million people. Reports indicate over 53,000 casualties in Turkey, with more than 230,000 buildings collapsing or suffering severe damage. This paper presents the findings of a post-earthquake reconnaissance field mission by describing the damage sustained in Malatya province. To this end, a summary of the strong ground motion data measured during two earthquakes at different stations is provided first. Subsequently, a more detailed evaluation of the ground motion parameters is presented for the data collected from seismic stations located in Malatya. An assessment of the damage observed in various structures, such as reinforced concrete, precast concrete, masonry, and steel structures, within the Malatya province is presented then. Finding of this study indicates that deficiencies in material quality (poor concrete quality, corrosion in steel and cold joint), improper manufacturing process and design mistakes (weak column-strong beam, short column, adjacent buildings, soft and weak story) are the major causes of the damage observed in Malatya.Öğe Seismic Performances of Different Strengthening Techniques in Masonry Residential Buildings(Univ Osijek, Tech Fac, 2026) Ozmen, AlperThis study evaluates the seismic performance and retrofitting strategies for a masonry residential building in Malatya, T & uuml;rkiye, that collapsed during the February 6, 2023, Kahramanmara & scedil; earthquake owing to an illegally added story. Nonlinear static (pushover) and dynamic (time history) analyses were performed using a finite-element macro-model. The unretrofitted structure collapsed at approximately 0.45 g in the longitudinal direction. Two retrofitting techniques, namely stainless steel strip jacketing and carbon fiber-reinforced polymer (CFRP) laminates, were investigated. The strengthened models demonstrated significantly improved seismic performance: the stainless steel strip retrofit increased the base shear capacity to 0.69 g, whereas the CFRP retrofitting further enhanced it to 0.79 g. Both methods also reduced the maximum inter storey drift ratios (from 0.50% to 0.34% for CFRP) and limited the crack widths (from 17.8 mm to less than 8 mm). CFRP retrofitting provided the most effective improvement. These results highlight the urgent need to retrofit unauthorized story additions in masonry buildings to enhance seismic resilience and inform policy decisions in seismically active regions.Öğe Seismic Response of a Historical Masonry Bridge under Near and Far-fault Ground Motions(Budapest Univ Technology Economics, 2021) Ozmen, Alper; Sayin, ErkutHistorical masonry arch bridges which might be vulnerable to natural disasters are important part of the cultural heritage. Natural disasters, especially earthquakes can inflict damage to these structural systems. This paper aims to investigate a comparison of the effects of near and far-fault ground motions on the seismic response of masonry arch bridges under different earthquakes. Kalender masonry arch bridge which is located in Ergani, Turkey is selected as a numerical model. For this purpose, three-dimensional finite element model of the bridge is generated with ANSYS finite element software with macro modelling approach. Seismic response of the bridge is assessed by means of time-history analyses. The near-fault and far-fault ground motions, which have approximately equal peak ground accelerations, of 1979 Imperial Valley, 1999 Chi-Chi, 1999 Kocaeli and 2010 Darfield earthquakes are considered for the analyses. Comparisons between maximum displacements, maximum and minimum stress, which were acquired from the dynamic analyses of the masonry bridge subjected to each fault effect, are obtained. The study demonstrates that far-fault ground motions are as important as near-fault ground motions and it can be used together with near-fault ground motion for further evaluation of such historical masonry bridges.Öğe SEISMIC RESPONSE OF SINGLE SPAN MASONRY ARCH BRIDGES LOCATED IN ELAZIG AND MALATYA(Int Journal Bridge Engineering, 2023) Ozmen, Alper; Sayin, ErkutHistorical masonry arch bridges are a major portion of the transportation network in the world. They are mostly constructed with brick and stone materials. These structures are reasonably important, for transferring the history and life style of ancient societies. They have to protect against the unexpected effects (i.e., floods, fire, and earthquake). Due to these factors, seismic behavior of these structures must be well known. In this paper, three different single span masonry arch bridges (Veli Palas, Musa Palas and Mavilik) were chosen as a case study. ANSYS software was used to generate three-dimensional finite element model of the bridges. 1992 Erzincan, 1999 Duzce and 2003 Bingol earthquake records were used for dynamic time history analyses. Displacements, principal stresses, potential damage regions and seismic response of masonry bridges were evaluated after the dynamic analyses.
