Effect of Anisotropy on Basic and Residual Friction Angles in Schist Rocks

Year 2023, Volume: 23 Issue: 1, 208 - 215, 01.03.2023

Mehmet Özdemir Sunay Beyhan Kaan Erarslan

https://doi.org/10.35414/akufemubid.1149778

Abstract

The basic friction angle (φb) tests are a common and practical method used to determine the shear strength of discontinuities. Tilt device is generally used in basic friction angle experiments. In this study, the effects of the anisotropy properties of green and mica schist rocks taken from the copper mine site in Kastamonu Hanönü district on the basic and residual friction angles were investigated. For this purpose, experiments with a specially designed tilt device were conducted on dried and saturated green schist and mica schist samples with orientation angles of 0°, 15°, 30°, 45°, 60°, 75° and 90° relative to the loading axis. According to the results in dried and saturated conditions, maximum basic and residual friction angle values were obtained for green schist samples at 60°. The results were close to each other in the experiments carried out in both saturated and dried conditions. Green schist samples were less affected by the saturated media. Mica schist samples were not affected by anisotropy for both media, and close values were obtained in all orientation angles. It was determined that the basic and residual friction angles were lower in saturated conditions compared to dried ones.

Keywords

Anisotropy, Mica Schist, Tilt Device, Green Schist

Supporting Institution

Kütahya Dumlupınar Üniversitesi BAP Koordinatörlüğü

Project Number

2019-05

Thanks

The authors would like to thank Kütahya Dumlupınar University BAP Coordinatorship for financial support with the project numbered 2019-05.

Şist Kayaçlarında Anizotropinin Temel ve Rezidüel Sürtünme Açılarına Etkisi

Abstract

Temel sürtünme açısı (φb) deneyleri süreksizliklerin kayma dayanımının belirlenmesi için kullanılan yaygın ve pratik bir yöntemdir. Temel sürtünme açısı deneylerinde genel olarak tilt cihazı kullanılmaktadır. Bu çalışmada, Kastamonu Hanönü ilçesindeki bakır madeni sahasından alınan yeşil ve mika şist kayaçlarının anizotropi özelliklerinin temel ve rezidüel sürtünme açılarına etkisi incelenmiştir. Bu amaçla, yükleme eksenine göre 0°, 15°, 30°, 45°, 60°, 75° ve 90° yönelim açısına sahip kuru ve doygun yeşil şist ve mika şist numunelerine özel olarak tasarlanan tilt cihazı ile deneyler uygulanmıştır. Kuru ve doygun ortamlardaki sonuçlara göre yeşil şist numuneleri için 60°de maksimum temel ve rezidüel sürtünme açısı değerleri elde edilmiştir. Hem doygun hem de kuru ortam şartlarında yapılan deneylerde birbirine yakın sonuçlar elde edilmiştir. Doygun ortamdan yeşil şist numuneleri daha az etkilenmiştir. Mika şist numuneleri ise her iki ortam için anizotropiden etkilenmemiş ve tüm yönelim açılarında yakın değerler elde edilmiştir. Doygun ortam şartlarında temel ve rezidüel sürtünme açısının, kuru ortam şartlarına kıyasla daha düşük değerlerde olduğu belirlenmiştir.

Keywords

Anizotropi, Mika Şist, Tilt Deneyi, Yeşil Şist

Project Number

2019-05

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