İki Farklı Karot Beşiği Kullanılarak Elde Edilen Leeb Sertlik Deneyi Verilerinin Analizi
Bu çalışmada, Equotip sertlik cihazı kullanılarak ölçülen kaya malzemesi Leeb sertliği (HL) değerlerinin karot beşiği türüne göre değişiklik gösterip göstermediği araştırılmıştır. Bu amaçla, farklı kayaçlara ait NX-boyutlu karot deney örnekleri ‘Kavis-biçimli’ ve ‘V-biçimli’ beşikler üzerinde Leeb sertliği deneylerine tabi tutulmuştur. Sonuçlar, kavis-biçimli (H$LA$) ve V-biçimli (H$LV$) beşiklerden elden edilen ortalama geri sıçrama sertlik değerleri arasında kuvvetli bir doğrusal ilişki ($R2$ 0.95) bulunduğunu göstermiştir. İki beşikten elde edilen HL değerleri arasındaki en yüksek fark HL-ölçeğinde 74,2 birim olup % 10,2’lik bir farklılığa karşılık gelmektedir. H$LA$ ve H$LV$ değerleri arasındaki farklılıkların az olmasına ve kayaç türüne göre değişiklik göstermesine rağmen, V-biçimli beşiğin görece daha küçük değerler verme eğilimi gösterdiği belirlenmiştir. Diğer yandan, minimum değerlerlerle karşılaştırıldığında, maksimum H$LA$ ve H$LV$ değerleri arasında daha yüksek bir istatistiksel ilişki bulunduğu gözlenmiştir. Sonuçlar ayrıca, deneyleri yapılan kayaçların tek eksenli basma dayanımı kestiriminde her iki beşiğin de güvenilir bir şekilde kullanılabileceğini göstermiştir.
Analysis of the Leeb Hardness Test Data Obtained by Using Two Different Rock Core Holders
In this study, an investigation was carried out to elucidate if the coreholder type affects the measured Leeb hardness values (HL) of rock materialsobtained by using the Equotip hardness tester. To achieve this goal, NX-size corespecimens of different rock samples were subjected to Leeb hardness testing byemploying an ‘Arch-shaped’ and a ‘V-shaped’ core holder. The results indicated astrong degree of linear correlation ($R2$ 0.95) between mean rebound hardnessvalues determined in the arch-shaped holder (H$LA$) and V-shaped holder (H$LV$).The maximum difference in HL values obtained from the two holders was 74.2units on the HL-scale, corresponding to a difference of 10.2 %. Although thedifferences in magnitudes of H$LA$ and H$LV$ values were small and varied from onerock variety to another, there was a tendency of the V-shaped holder to giverelatively lower values. On the other hand, when compared to the minimum values,a higher statistical correspondence was observed between maximum H$LA$ and H$LV$values. The results also showed that it is possible to predict uniaxial compressivestrength of the tested rocks reliably by employing any of the holders.
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