Cyclic Lateral Loading Behavior of Thin-Shell Precast Concrete Wall Panels
Sevil Yaman, Tuğçe
Two precast concrete thin-shell wall panels were subjected to reverse-cyclic lateral loads to simulate wind fatigue over a 50-year design lifetime prior to loading to failure. The panels consisted of an outer wythe of concrete connected to light gauge steel framing. Wire mesh was used to reinforce the concrete panel skin. Rivets provided a connection between the steel studs and the concrete panel. Two reinforced concrete (R/C) beams were integrated into the top and bottom of the panel, isolated from the concrete face by a thin layer of extruded polystyrene (XPS) foam insulation. Carbon fiber reinforced polymer (CFRP) grid was used to connect these beams with the concrete face through the rigid foam insulation. The objective of the testing program was to characterize the behavior of the con...
2023 Kahramanmaraş ve Hatay depremlerinin Antakya ve Samandağ ilçelerindeki yapısal etkileri ve çözüm önerileri
Akın, Emre | Kara, İlker Fatih
06.02.2023 tarihinde Doğu Anadolu Fay Zonu (DAFZ) üzerinde yerel saat 04:17’de Mw: 7.7 büyüklüğünde ve yerel saat 13:24’de Mw: 7.6 büyüklüğünde olan Kahramanmaraş merkezli iki adet büyük şiddetli depremler meydana gelmiştir. Bu depremlerden sonra 20.02.2023 tarihinde Ölü Deniz Fayı üzerinde yerel saat 20:04’te Mw: 6.4 büyüklüğünde Hatay merkezli yıkıcı bir deprem daha meydana gelmiştir. Bu depremlerden en çok etkilenen bölgelerin başında Hatay ili gelmektedir. Bu çalışmada depremden sonra Hatay’ın Antakya ve Samandağ ilçelerinde bulunan yapılardaki hasarlar gözleme dayalı olarak değerlendirilmiştir. Oluşan hasarların sayısı göz önüne alındığında bölgedeki yapı stoğunun depreme karşı yetersiz olduğu anlaşılmaktadır. Deprem yönetmeliklerine uygun olarak yapılan binaların yıkılmadığı ve diğer...
Strength properties of roller compacted concrete containing a non-standard high calcium fly ash
Özcan, Fatih | Bilim, Cahit
Although roller compacted concrete (RCC) made with and without fly ash (FA) has enjoyed numerous application of dams, roads and large floors construction in Europe, Japan, Australia and Unites States since 1970s, it has not almost yet been used at all in Turkey despite abundant and economical sources of FA and cement. This reluctance has arised due to the lack of confidence and the lack of technical experience in the concrete engineering field. In order to build, to some extend, the confidence and gain technical experience about RCC made with and without FA, a series of laboratory work was undertaken. In the present work, the RCCs were produced with three different cement quantity including 200, 300 and 400 kg/m3 normal Portland cement (NPC). A FA, which is a local material, was also used ...
Yemler Bilgisi Yem Teknolojisi ve Balık Besleme
Bilgüven, Murat
Her havuz alanında ya da yetiştirme biriminden elde edilen balık ve dolayısıyla balık yetiştiriciliğinin kârlılığı, büyük ölçüde kullanılan yemin miktarına bağlıdır. Su ürünleri sistemi ne kadar yoğun olursa yemlemenin önemi o kadar fazla olur ve toplam üretim maliyetinde yem maliyetinin payı da o kadar artar. Bilindiği üzere alabalık başta olmak üzere bazı balıkların yetiştiriciliği için akarsu sistemli tesisler kullanılmakta yada sıcaklığın, su bileşiminin ve akıntının dolayısıyla oksijen yoğunluğunun daha iyi olduğu tatlı su ve kıyılarda ise yüzer ağ kafeslerde yetiştiricilik yapılmaktadır. Su ürünleri yetiştiriciliğinin ileri durumda olduğu ülkelerde entansif yetiştiricilik uygulanmakta ve yetiştirme alanlarında birim hacimde maksimum ürün yetiştirilmeye çalışılmaktadır. Bu tür yetişti...
The use of a non-standard high calcium fly ash in concrete and its response to accelerated curing
Bilim, Cahit | Özcan, Fatih
An experimental work was carried out to investigate the use of a non-standard high calcium fiy ash in concrete. The response of the same fly ash to the accelerated curing was also explored. With three different cementitious material contents, a total of 48 concretes were produced. The water/cement ratios were varied from 0.40 to 0.87. Compressive strengths of the moist cured cube specimens cast from the concrete mixtures made with 0%, 15%, 30% and 45% replacement of normal Portland cement with fly ash were measured at 28 days and 3 months. Accelerated compressive strengths were also measured using warm-water method and boiling-water method in accordance with the relevant ASTM and Turkish Standards. Despite the fact that the fly ash used was a non-standard, the laboratory test results showe...
Role of antioxidant defense system and biochemical adaptation on stress tolerance of high mountain and steppe plants
Keleş, Yüksel
Eleven species were collected from Northwest Anatolian mountains (1500–2000 m) and 18 species were collected from the Central Anatolian steppes (850–1000 m) in June 1998 and 1999. In all the species investigated, the water and dry matter percentages and solute contents were measured. The chlorophyll, b-carotene, ascorbate and a-tocopherol contents and catalase (CAT), superoxide dismutase (SOD) andglutathione reductase (GR)enzymeactivities oftheplants werealsodetermined.Thesteppeplantshadlowerwatercontentcomparedwith alpine plants. The chlorophyll contents of the plants investigated did not change with altitude. However, the carotenoid/chlorophyll ratio of alpine plants was found to be significantly higher. The antioxidant/chlorophyll ratio of the trees and shrubs was higher than that of he...