SPECIMEN GEOMETRY AND LOADING RATE CONDITION EFFECT ON INDIRECT TENSILE STRENGTH VALUES OF ROCK MATERIALS

Abstract

In this study, rock core specimens with same diameter and different length to diameter ratios were tested under deformation controlled and load controlled various loading rate conditions. According to the results obtained from 5 different types of rock material and 90 specimens tested in this study, measured indirect tensile strength values were found to significantly increase with a decrease in the ratio of length to diameter under load controlled loading rate (kN/s) condition. To minimize the effect of geometry of the specimens and obtain similar results from specimens with different length to diameter ratios, the indirect tensile strength (Brazilian) test was suggested to carry out under the condition of deformation controlled loading rate (mm/min) selection.

Keywords

• Indirect Tensile Strength,Brazilian Test,Rock Mechanics Experiments,Specimen Geometry,Loading Rate

NUMUNE GEOMETRİSİ VE YÜKLEME HIZI KOŞULLARININ KAYA MALZEMELERİ DOLAYLI ÇEKME DAYANIMI DEĞERLERİ ÜZERİNDEKİ ETKİLERİ

Abstract

Bu çalışmada, aynı çap ve farklı boy/çap oranlarına sahip kaya malzemesi numuneleri deformasyon kontrollü ve yük kontrollü olarak farklı yükleme hızı koşullarında test edilmiştir. 5 farklı kaya malzemesi ve toplam 90 adet dolaylı çekme dayanımı (Brezilyan) testi numunelerinden elde edilen sonuçlara göre, yük kontrollü bir yükleme hızı (kN/s) seçimi koşulunda boy/çap oranı artışı ile hesaplanan dayanım değerlerinde belirgin ölçüde azalma olduğu görülmüştür. Numune geometrisi etkisinin minimize edilmesi, farklı boy/çap oranlarına sahip numunelerden benzer dayanım değerlerinin elde edilmesi için deformasyon kontrollü yükleme hızı (mm/dakika) seçilerek dolaylı çekme dayanımı testlerinin gerçekleştirilmesi önerilmiştir.

Keywords

• Dolaylı Çekme Dayanımı,Brezilyan Testi,Kaya Mekaniği Deneyleri,Numune Geometrisi,Yükleme Hızı

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