Investigation of the Impacts of W/C Ratio and Hyper Plasticizer Ratio on Final Setting Time and Compressive Strength for the Concretes to which Alternating Current Applied

Yıl 2019, , 1045 - 1051, 01.12.2019

İsmail Hocaoğlu , Tayfun Uygunoğlu

https://doi.org/10.2339/politeknik.480915

Cited By: 1

Öz

In this study,
80 V AC current is applied to 300 dosaged concretes whose water/cement ratios
are 0.45, 0.55, 0.65 and 0.70. Admixtures having different hyper plasticizer
ratios (0.5 %, 1 % and 1.5 %) and admixtures having constant water/cement ratio
(0.55) at 300 dosaged levels were prepared. Electrical current was applied to
the fresh concretes in the electrically isolated molds whose sizes are 10cm x
10cm x 35cm. The measurements were done at room temperature. As a result of
measuring internal temperatures of concretes, the differences between final
setting time with and without electric current application on the specimens
were investigated. The effects of Alternating Current (AC), water/cement ratio,
hyper plasticizer ratio on final setting time, 1 day compressive strength and
28 day compressive strength are investigated. It is aimed to shorten the
duration of final setting time through adding hyper plasticizer in a certain
rate to the concrete and application of AC current. As a result, adding little
hyper plasticizer (0.5 %) and application of 80 V AC electrical current to the
concretes shorten the setting time without critical compressive strength loss.

Anahtar Kelimeler

Alternating voltage, concrete, final setting time

Alternatif Gerilim Uygulanan Betonlarda S/Ç Oranının ve Hiperakışkanlaştırıcı Oranının Priz Bitiş Süresi ve Basınç Dayanımına Etkilerinin Araştırılması

Öz

Bu çalışmada su/çimento oranları
0.45, 0.55, 0.65 ve 0.70 olan 300 dozajlı betonlara 80 V AC gerilim
uygulanmıştır. S/ç oranları 0.55 olan % 0.5, % 1 ve % 1.5 oranlarında
hiperakışkanlaştırıcı konulan betonlar üretilmiştir. Taze haldeki betonlar
elektriksel yalıtımlı 10cm x 10cm x 35cm boyutlarındaki kalıplar içerisinde
elektrik akımı uygulanmış, ölçümler oda sıcaklığında yapılmıştır. Elektrik
akımı uygulanmış ve elektrik akımı uygulanmamış numunelerde iç sıcaklık ölçümü
ile priz bitiş süresi belirlenmiştir. Alternatif gerilimin, s/ç oranının ve
hiperakışkanlaştırıcı oranının priz sona erme süresi, 1 günlük basınç dayanımı
ve 28 günlük basınç dayanımına etkileri araştırılmıştır. Bu araştırmada betona
belirli oranda hiperakışkanlaştırıcı konulması ve alternatif gerilim uygulaması
sonucu priz bitiş süresinin kısaltılması amaçlanmıştır. Betonlara az miktarda
(% 0.5) hiperakışkanlaştırıcı konulması ve 80 V AC gerilim uygulaması ile ciddi
basınç dayanım kaybı yaşanmadan priz süresinin kısaltılabileceği
belirlenmiştir. 

Anahtar Kelimeler

Alternatif gerilim, beton, priz bitiş süresi

Kaynakça

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