ÇEPER ETKİSİ OLUŞMAYAN FARKLI BİÇİM VE BOYUTTAKİ BETON NUMUNELERİN BASINÇ DAYANIMLARININ DENEYSEL KARŞILAŞTIRILMASI

Year 2014, Volume: 6 Issue: 3, 29 - 48, 01.09.2014

Can Demirel Ahmet Gökdemir

Abstract

Beton basınç dayanımında geometrinin önemine ait birçok çalışma yapılmıştır. Bu çalışmada da beton numunelerde geometrinin ve narinliğinin önemini görmek için çeper etkisi oluşumu engellenerek basınç dayanımları incelenmiştir. 28 günlük basınç dayanımları incelendiğinde en yüksek dayanım 100 mm ayrıtlı küp numune olan 100G’de 34,133 değeri ile elde edilmiştir. Standart numune olan 150 mm ayrıtlı küp numunede ise 33,600 Mpa değeri elde edilmiş ve en az 30 Mpa olması gereken değer sağlanmıştır. En az 25 Mpa değeri aranan 150x300 mm silindir numunede 27,633 Mpa dayanım elde edilirken 100x200 mm silindir numunede 29,500 Mpa’lık dayanım elde edilmiştir. Kimyasal kür uygulanan numunelerde ise beklenenin aksine fazla bir dayanım artışı olmazken bu tür malzemelerin küçük yüzey alanlardaki etkisinin çok olmadığı tespit edilmiştir. Yapılan deneysel çalışma sonucu sahada kullanılan beton karışımını içindeki maksimum agrega boyutuna uygun numune kalıbı seçilmesinin daha doğru olacağı tespit edilmiştir. Ayrıca farklı geometrideki numuneler arasında geçiş katsayıları ve çeşitli modeller önerilmiştir.

Keywords

Çeper Etkisi, Beton Numune, Basınç Dayanımı, Beton Karışım

EXPERIMENTAL COMPARISON OF CONCRETE SPECIMENS HAVING DIFFERENT FORM AND SIZES WITHOUT WALL EFFECT FORMATION

Abstract

Many studies have been done on geometry’s importance in concrete compression resistance. In this study because of seeing the importance of geometry and slimness in concrete samples, compression resistances have been analysed by preventing the wall effect process. If the 28-day-compression resistances are examined, the highest resistance is obtained from the 100 mm-edged cube sample in 100G with the value 34,133. In the 150 mm-edged cube sample which is a standard sample, the value 33600 Mpa is obtained and the minimum value is provided that must be 30 Mpa. In the 150x300 mm cylinder sample looking for the minimum value 25 Mpa, 27,633 Mpa resistance is obtained while in the 100x200 mm cylinder sample resistance of 29,500 Mpa is obtained. In chemical cure performed samples resistance increase isn’t very much on the contrary it has been determined that effects on small surfaces of this kind of materials aren’t very much. By the result of the experimental study it has been fixed that it would be useful to choose sample formwork necessary for maximum aggregate size in concrete mixture used in the field. Furthermore pass parameters between samples in different geometry and various models have been suggested.

Keywords

Wall Effect, Concrete Sample, compressive strength, Concrete Mixtur

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