Yazar "Ozturk, B." seçeneğine göre listele
Listeleniyor 1 - 4 / 4
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Application of destruction specific energy for characterisation of concrete paving blocks(THOMAS TELFORD PUBLISHING, 2009) Atici, U.; Ersoy, A.; Ozturk, B.Concrete interlocking paving blocks (CIPB) are used in a variety of commercial, municipal and industrial applications. This study aimed to develop a prescription (optimum parameters of aggregate proportion, water/cement (w/c) ratio and dosage) for producing CIPB based on destruction specific energy (SE(des)), strength, hardness and abrasion resistance. In developing countries, CIPB are being produced by a trial and error method, which results in uneconomical and low engineering properties. This may arise as a result of the lack of confidence and the lack of technical experience in the CIPB field. In order to gain these qualifications, optimum water/cement (w/c) ratio and dosages, and optimum aggregate characteristics at different ages are determined for CIPB within the scope of the presented study. Recently defined SEdes, which is estimated from the area (integral) under the stress strain envelope in unconfined compression test, is used. The splitting and flexural tensile strengths, rebound hardness and abrasion resistance results showed consistency with the SEdes. The optimum parameters of aggregate proportion, w/c ratio and dosage are obtained. Accordingly, the application of SEdes for production of CIPB results in lower cost and higher quality engineering properties for CIPB.Öğe DETERMINATION OF OPTIMAL ELASTIC SPRINGS FOR CANTILEVER BEAMS SUPPORTED BY ELASTIC FOUNDATION(Acad Sci Czech Republic, Inst Theoretical & Applied Mechanics, 2018) Aydin, E.; Ozturk, B.; Dutkiewicz, M.In this study, the optimum distribution of the elastic springs in which a built-in cantilever beam is seated, so as to minimize the shear force on the support of the beam, is investigated. The Fourier transform is applied to the vibration equation of the beam written in the time domain and is shown by the structural behaviour transfer function which is made independent from the external influence. For the first and second modes of beam, the optimum locations and amounts of the springs were investigated so that the shear force transfer function amplitude was minimal. Stiffness coefficients of springs are taken as design variables. There are active constraints on the sum of the spring coefficients taken as design variables and passive constraints on each of them as the upper and lower bounds. Optimality criteria are derived using the Lagrange Multipliers method. The gradient information required for solving the optimization problem is analytically derived. Numerical results show that the aimed method is quite effective in finding optimum spring stiffness coefficients.Öğe OPTIMAL PASSIVE CONTROL OF SHEAR BUILDINGS(Acad Sci Czech Republic, Inst Thermomechanics, 2017) Aydin, E.; Ozturk, B.; Dutkiewicz, M.In the paper, the analysis of damping parameters for vibration reduction of buildings with use of optimization algorithm is presented. Optimal values of damping coefficients are determined at fundamental structural mode of shear buildings in order to attain desired added damping ratios. The cost function is defined as the sum of damping coefficients of the dampers to be minimized. Proposed optimization problem is solved by using three different numerical algorithms that are namely: Simulated Annealing, Nelder Mead and Differential Evolution algorithms, respectively. Numerical example is presented to prove the validity of the proposed method. The changes of optimal distributions of the dampers with respect to target damping ratios and structural periods in a particular range are investigated for two-story shear building model. The numerical results show that the proposed damper optimization method is easy to apply and efficient to find optimal damper distribution for a target damping ratio.Öğe The evaluation of damage mechanism of unreinforced masonry buildings after Van (2011) and Elazig (2010) Earthquakes(IOP PUBLISHING LTD, 2015) Guney, D.; Aydin, E.; Ozturk, B.On March 8th, 2010 Karakocan-Elazig earthquake of magnitude 6.0 occurred at a region where masonry and adobe construction is very common Karakocan-Elazig is located in a high seismicity region on Eastern Anatolian Fault System (EAFS). Due to the earthquake, 42 people were killed and 14'113 buildings were damaged. Another city, Van located at South east of Turkey is hit by earthquakes with M = 7.2 occurred on October 23rd, 2011 at 13:41 (local time), whose epicenter was about 16 km north of Van (Tabanli village) and M = 5.6 on November 9th, 2011 with an epicenter near the town of Edremit, south of Van and caused the loss of life and heavy damages. Both earthquakes killed 644 people and 2608 people were injured. Approximately 10'000 buildings were seriously damaged. There are many traditional types of structures existing in the region hit by earthquakes (both Van and Elazig). These buildings were built as adobe, unreinforced masonry or mixed type. These types of buildings are very common in rural areas (especially south and east) of Turkey because of easy workmanship and cheap construction cost. Many of those traditional type structures experienced serious damages. The use of masonry is very common in some of the world's most hazard-prone regions, such as in Latin America, Africa, the Indian subcontinent and other parts of Asia, the Middle East, and southern Europe. Based on damage and failure mechanism of those buildings, the parameters affecting the seismic performance of those traditional buildings are analyzed in this paper. The foundation type, soil conditions, production method of the masonry blocks, construction method, the geometry of the masonry walls, workmanship quality, existence of wooden beams, type of roof, mortar between adobe blocks are studied in order to understand the reason of damage for these types of buildings.
