Yazar "Karadeniz, Halil" seçeneğine göre listele

Listeleniyor 1 - 5 / 5
  • [ X ]
    Öğe
    Ambient vibration based-simplified frequency formulas for historical masonry stone mosques with timber truss roofs
    (Routledge Journals, Taylor & Francis Ltd, 2020) Calik, Ismet; Bayraktar, Alemdar; Turker, Temel; Karadeniz, Halil
    Historical masonry stone mosques with timber truss roofs were widely constructed all over the world. Due to the complex structural behaviors of this type of building, it is difficult to determine natural frequencies during the seismic safety evaluations numerically. The article aims to develop simplified natural frequency formulas based on ambient vibrations for the historical masonry stone mosques with timber truss roofs. Fourteen masonry stone mosques with timber truss roofs built in the Eastern Black Sea Region of Turkey are selected for the study. Experimental natural frequencies, mode shapes and damping ratios of the selected mosques under ambient vibrations are determined using the Operational Modal Analyses. Ambient vibration-based simplified natural frequency formulas based on the geometrical dimensions for the masonry stone mosques with timber truss roofs are obtained by using the statistical regression analysis. The proposed formulas for the first three frequencies are verified with the control data.
  • [ X ]
    Öğe
    Baraj Emniyeti İçin Gözlemsel İnceleme Ve Değerlendirmelerin Rolü
    (Su Vakfı, 2020) Emiroğlu, M. Emin; Edıl, Tuncer B.; Kalkan, Yunus; Karadeniz, Halil; Celep, Zekai
    Bu çalışmada, periyodik olarak yapılan gözlemsel incelemelerin ve değerlendirmelerin rolü tartışılmıştır. Çeşitli ölçüm aletlerinin etkili kullanımı, sürekli ve güvenilir verilerin temini ve verilerin kayıt altına alınması ve değerlendirilmeleri tartışılmıştır. Barajların emniyeti; sosyal, ekonomik ve çevresel faktörler bakımından oldukça önemlidir. Baraj emniyeti için yapılan detaylı gözlemsel inceleme ve değerlendirmeler, barajların önemine, karmaşık tasarımına ve barajın hasar görme seviyesine göre değişiklik göstermektedir. Barajların emniyeti için barajlarda yapılan ölçüm sonuçlarının kayıt altına alınması ve gerekli durumlarda arazi ve laboratuvar deneylerinin yapılması önem taşımaktadır. Baraj emniyeti değerlendirmelerinde, farklı disiplinlerdeki uzmanların birlikte çalışmaları önemlidir. Barajların ve ilave yapılarının emniyetinin incelenmesinde sadece nicel veriler değil aynı zamanda sözel ifadelerinde bilgisayar ortamında kayıt altına alınması oldukça önemlidir.
  • [ X ]
    Öğe
    Monitored structural behavior of a long span cable-stayed bridge under environmental effects
    (2018) Bayraktar, Alemdar; Ashour, Ashraf; Karadeniz, Halil; Kurşun, Altok; Erdiş, Arif
    An accurate numerical analysis of the behavior of long-span cable-stayed bridges underenvironmental effects is a challenge because of complex, uncertain and varyingenvironmental meteorology. This study aims to investigate in-situ experimentalstructural behavior of long-span steel cable-stayed bridges under environmental effectssuch as air temperature and wind using the monitoring data. Nissibi cablestayedbridge with total length of 610m constructed in the city of Adıyaman, Turkey,in 2015 is chosen for this purpose. Structural behaviors of the main structural elementsincluding deck, towers (pylons) and cables of the selected long span cablestayedbridge under environmental effects such as air temperature and wind are investigatedby using daily monitoring data. The daily variations of cable forces, cableaccelerations, pylon accelerations and deck accelerations with air temperature andwind speed are compared using the hottest summer (July 31, 2015) and the coldestwinter (January 1, 2016) days data.
  • [ X ]
    Öğe
    Structural performance of Nissibi cable-stayed bridge during the main and aftershocks of Adıyaman-Samsat earthquake on March 2, 2017
    (Springer International Publishing, 2019) Bayraktar, Alemdar; Ashour, Ashraf; Karadeniz, Halil; Kurşun, Altok; Erdiş, Arif
    The structural performances of long span cable-stayed bridges having different elements such as pylons, stayed cables and decks are very sensitive to earthquake ground motions due to their highly statically indeterminacy. Therefore, responses of pylon, cable and deck components of long span cable-stayed bridges should be continuously monitored to prevent structural damages. The present study aims to investigate the responses of pylons, stayed cables and deck components of Nissibi cable-stayed bridge during the main (M w = 5.5) and aftershocks (M w = 3.5-4.4) of Adıyaman-Samsat (Turkey) earthquake on March 2, 2017. Firstly, the properties of structural and fixed monitoring systems of Nissibi bridge are introduced, and active faults and earthquake zoning maps of Adıyaman, acceleration records and shake map of main and aftershocks of the earthquake are presented. Then, responses of the pylon, deck and cable elements during the main and aftershocks are obtained using the data taken from the fixed bridge monitoring system. The forces in cables and accelerations in the two pylons and deck are evaluated and compared with each other. © 2019, Springer Nature Switzerland AG.
  • [ X ]
    Öğe
    Vertical strong ground motion effects on seismic damage propagations of historical masonry rectangular minarets
    (Pergamon-Elsevier Science Ltd, 2018) Bayraktar, Alemdar; Hokelekli, Emin; Halifeoglu, F. Meral; Mosallam, Ayman; Karadeniz, Halil
    Masonry towers and minarets are slender tall structures and highly vulnerable to strong ground motions due to their structural and material characteristics. The paper aims to investigate the effect of vertical ground motion on damage propagations of historical masonry slender tall rectangular stone minarets numerically. The Ulu Mosque minaret with height of 42.90 m constructed in 639 in Diyarbakir, Turkey, is selected as an application. Firstly, three dimensional solid and continuum finite element models of the minaret are obtained from the surveys. Since the foundation of the minaret is sitted on the hard soil, soil-structure interaction is not considered in the finite element model. The finite element model of the minaret is updated by modal analyses results and an empirical frequency formulation developed using the measurement results. Mechanical material properties of the masonry unit are determined using the properties of the stone and mortar used in the minaret. Concrete damaged plasticity (CDP) material model adjusted to masonry structures is considered in the nonlinear analyses. The acceleration records of horizontal (N-S) and vertical (V) components of May 1, 2003 Bingol earthquake (Mw = 6.4), which was recorded in hard soil and occurred in the near region of Diyarbakir city, are chosen as a strong ground motion. Then, linear time history and nonlinear step by step seismic analyses of the minaret are implemented for only horizontal, and combined horizontal and vertical components of the earthquake. The time histories of displacements, minimum and maximum principal strains and stresses, and damage propagations on the minaret are compared for only horizontal, and combined horizontal and vertical load cases including self-weight. It can be stated that consideration of vertical ground motion component in combination with horizontal component affects damage percentages and propagations on slender tall rectangular stone minarets.