The effect of temperature and pH on the strength anisotropy of schists

Year 2023, Volume: 12 Issue: 4, 1318 - 1324, 15.10.2023

Mehmet Özdemir , Sunay Beyhan , Kaan Erarslan

https://doi.org/10.28948/ngumuh.1308451

Abstract

Rock strength is an important parameter in mining project processes. The distribution of strength values is important in rocks showing different strength properties according to orientations in terms of strength anisotropy, such as sedimentary and metamorphic rocks. The studies can be carried out at different temperatures and pHs. Strength values may change in summer, winter, acidic and basic conditions. In this study, schist samples were taken from the copper mine in the Hanönü district of Kastamonu, Türkiye. Besides the strength anisotropy of metamorphic rocks such as green schist and mica schist, the variation of strength values at different temperatures (5°C and 35°C) and pH (2, 7 and 12) was investigated. In general, minimum strengths at 15°-45° and maximum results between 60°-90° degrees were obtained for both rocks. Generally, both rocks showed maximum strength distribution at 5°C. Maximum strength was obtained at pH12 for mica schist, close distribution at other pH values, and similar distribution at all pH values for green schist. The degree, temperature, and pH parameters affected the strength of mica schist, while the degree and temperature parameters were effective in the strength of green schist. Examination of the effect of the change of different parameters on the strength of the rocks will contribute to the project and operation processes.

Keywords

Anisotropy, Mica Schist, pH, Temperature, Green Schist

Şistlerin dayanım anizotropisinde sıcaklık ve pH’ın etkisi

Abstract

Madencilik çalışmaları proje süreçlerinde kayaç dayanımı önemli bir parametredir. Sedimanter ve metamorfik kayaçlar gibi dayanım anizotropisi açısından yönelimlere göre farklı dayanım özellikleri gösteren kayaçlarda dayanım değerleri dağılımı önem arz etmektedir. Bunun birlikte farklı sıcaklıklarda ve pH’larda çalışmalar yapılabilmektedir. Yaz, kış, asidik ve bazik ortamlarda dayanım değerleri değişebilmektedir. Bu çalışmada Türkiye Kastamonu ili Hanönü ilçesindeki bakır madeninden şist numuneleri alınmıştır. Yeşil şist ve mika şist gibi metamorfik kayaçların dayanım anizotropisinin yanında farklı sıcaklık (5°C ve 35°C) ve pH’larda (2, 7 ve 12) dayanım değerlerinin değişimi incelenmiştir. Genel olarak her iki kayaç için 15°-45° derecelerde minimum dayanımlar, 60°-90° dereceler arasında ise maksimum sonuçlar elde edilmiştir. Genellikle her iki kayaç 5°C’de maksimum dayanım dağılımı göstermiştir. Mika şist için pH parametresinde maksimum dayanım pH12’de, diğer pH’larda yakın dağılım, yeşil şist için ise tüm pH değerlerinde benzer dağılım elde edilmiştir. Mika şist için derece, sıcaklık ve pH parametreleri, yeşil şist için ise derece ve sıcaklık parametreleri dayanımda etkili olmuştur. Kayaçlarda farklı parametrelerin değişiminin dayanıma etkisinin incelenmesi proje ve işletme süreçlerinde katkı sağlayacaktır.

Keywords

Anisotropy, Mika Şist, pH, Sıcaklık, Yeşil Şist

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