Tek eksenli ve kayma yükleri etkisi altında beton-beton arayüzünün mekanik özellikleri

Year 2018, Volume: 24 Issue: 6, 1037 - 1042, 18.12.2018

Nihat Kabay , Ahmet Beşer Kızılkanat

Abstract

Bu
deneysel çalışmada eski betonu temsilen normal dayanımlı beton ile yeni betonu
temsil eden farklı tipteki yüksek dayanımlı betonlar arasındaki aderans
dayanımının incelenmesi amaçlanmıştır. Farklı karakteristiğe sahip yeni beton
elde etmek amacı ile silis dumanı ve çelik lif kullanılmıştır. Farklı
kompozisyonlara sahip yüksek dayanımlı betonun aderans dayanımına etkisi eğik
kayma (slant shear) ve çift yüzey kayma (bi-surface shear) deneyleri ile
belirlenmiştir. Ayrıca eski/yeni beton kompozitlerin eksenel basınç yükü etkisi
altındaki mekanik özellikleri deneysel olarak belirlenmiştir. Elde edilen
sonuçlara göre yeni beton dayanımının ve kayma deneyinde kullanılan yöntemin
aderans dayanımı üzerinde önemli bir etkisi olduğu görülmüştür. Eğik kayma
deneyinin çift yüzey kayma deneyine göre 6-12 kat yüksek aderans dayanımı
verdiği tespit edilmiştir. Paralel model yaklaşımının eski/yeni beton
kompozitlerin elastisite modülünün tahmininde tatminkar sonuçlar verdiği
belirlenmiştir.

Keywords

Yapışma dayanımı, Eğik kayma deneyi, Çift yüzey kayma deneyi

Mechanical properties of concrete to concrete interfaces under uniaxial and shear forces

Abstract

This research
aims to evaluate the bond strength between normal strength substrate concrete
and different types of high strength overlay concretes. In order to obtain
different characteristics in the overlay concrete, silica fume and steel fibers
were used. The slant shear and bi-surface shear tests were conducted to
quantify the effect of different high strength concrete compositions on the
bond strength. The mechanical properties of overlay/substrate concrete
composites were also analysed on cylindrical samples under uniaxial compression
load. The results indicate that the strength of overlay plays an important role
on the bond mechanism. The bond strength is found to be dependent on the test mechanism.
The test results showed that the bond strength was about 6-12 times higher in
slant shear test compared to the bi-surface shear test. The application of
parallel model approach on the overlay/substrate concrete composites was found
to be quite satisfactory to predict the elastic modulus of the composite.

Keywords

Bond strength, Slant shear test, Bi-surface shear test

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