Farklı Standartlara Göre Silo Yüzeyindeki Dış Basınç Katsayılarının Belirlenmesi

Bu çalışmada 14 m yüksekliğinde ve 6 m çapa sahip çelik silindirik bir siloda farklı yükseklik/çap(h/dc) ve silo yüzeyine farklı rüzgar geliş açılarına (θw) göre rüzgar dış basınç katsayı (Cp) değerleri araştırılmıştır.Araştırmada dış basınç katsayıları için Eurocode (EN), Avustralya standardı (AS) ve İngiliz standardı (BS)kullanılmıştır. Araştırmada EN ve AS standartlarına göre hesaplamalar yapılarak katsayı değerleri elde edilmişolup BS standardı için verilen çizelge değerleri ile karşılaştırmalar yapılmıştır. EN ve AS standartlarına bağlı olarakfarklı h/dc oranlarında silo yüzeyine 20°’ lik rüzgar geliş açısına kadar pozitif Cp katsayıları elde edilmiştir. Siloyüzeyine 20°’ lik rüzgar geliş açısından sonraki açı değerlerinde ise negatif Cpkatsayıları belirlenmiştir. İstatistikanaliz sonucunda EN, AS ve BS standartları arasında istatiksel olarak P<0.05 düzeyinde önemli farklılıklar tespitedilmiştir. Sonuç olarak silo tasarımında önemli bir çevresel yük grubundan olan rüzgar yükünün hesaplanmasındarüzgar hızı, ve yörenin topoğrafk koşullarına bağlı olarak değişim gösterebilen Cpkatsayılarının dikkate alınaraktasarım yapılması gerekmektedir

Anahtar Kelimeler:

Avustralya standardı, dış basınç katsayısı, Eurocode, İngiliz standardı, silo

The Determination of External Pressure Coeffcients on The Silo Surface According to Different Standards

In this study, wind external pressure coeffcient (Cp) values were investigated according to differentheight/diameter (h/dc) and different wind arrival angles (θw) to the silo surface in a steel cylindrical silo with 14m height and 6 m diameter. Eurocode (EN), Australian standard (AS) and British standard (BS) were used for theexternal pressure coeffcients in the study. In the study, coeffcient values were obtained calculating according toEN and AS standards and compared with the table values given for the BS standard. Depending on the EN and ASstandards, positive Cpcoeffcients were obtained at different h/dc ratios up to a 20° wind arrival angle to the silosurface. Negative Cpcoeffcients were determined at higher values of the 20° wind arrival angle to the silo surface.Statistically signifcant differences (P<0.05) were found among the EN, AS and BS standards. As a result, designmust be made considering the Cpcoeffcients which can vary depending on the wind speed and the topographicconditions of the area in the calculation of the wind load which is one of the important environmental load groupsin the silo design.

Keywords:

Australian standard, external pressure coeffcient, Eurocode, British standard, silo,

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