Betonarme kirişlerde ultra yüksek dayanımlı beton kullanımının eğilme performansına etkisi

Abstract

Bu çalışmada, Ultra Yüksek Dayanımlı Beton’un (UYDB) betonarme kirişlerin eğilme davranışına etkileri deneysel ve sayısal olarak incelenmiştir.  Deneysel kısımda ortalama 135 MPa’ lık UYDB kullanılarak düşük ve yüksek donatı oranlarına sahip dört adet betonarme kiriş üretilmiş ve dört noktalı eğilme altında test edilmiştir.  Sayısal kısımda ise test kirişleri için UYDB ve normal dayanımlı beton kullanılarak kesit analizleri gerçekleştirilmiş ve sonuçlar karşılaştırılmıştır.  Sonuç olarak UYDB’nin özellikle yüksek donatı oranları için eğilme sünekliği, moment kapasitesi ve eğilme rijitliği parametreleri bakımından normal dayanımlı betona göre önemli avantajlar sağladığı görülmüştür. UYDB ile üretilen kirişlerin TS 500’de verilen maksimum donatı sınırının aşılmasına rağmen yeterli sünekliği sağladığı, hatta daha yüksek donatı oranlarının da kullanılabileceği düşünülmektedir.

Keywords

• Ultra yüksek dayanım,normal dayanım,beton,eğilme,donatı oranı,betonarme kiriş

Impact of ultra high strength concrete to flexural performance of RC beams

Abstract

In this study, the effects of Ultra High Strength Concrete (UHSC) on the flexural behavior of reinforced concrete beams have been investigated experimentally and numerically.  In the experimental section, four reinforced concrete beams with low and high reinforcement ratios were produced by using UHSC with an average compressive strength of 135 MPa and tested under four-point loading.  In the numerical section, cross section analyzes were carried out by using UHSC and normal strength concrete for test beams and the results were compared.  It has been observed that UHSC provides significant advantages over normal strength concrete in terms of flexural ductility, moment capacity and flexural stiffness especially for high reinforcement ratios.  It is considered that the beams produced with UHSC provide sufficient ductility even though the limit given in TS 500 is exceeded and higher reinforcement ratios can be used.

Keywords

• Ultra high strength,normal strength,concrete,flexure,reinforcement ratio,reinforced concrete beam

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