Determination of slope debris flow mechanism in an open pit mine

Abstract

On 17 November 2016, 16 workers lost their lives as a result of a landslide in an open pit copper mine in Madenköy district of Siirt province in southeastern Turkey. The main aims of this study is to investigate the causes of the accident, to reveal its mechanism and to be prepared for such mass movements that may occur in the future. The study area consists from the north and getting younger towards the south. Further investigations have shown that hydrogeological conditions and geological structure are the most important factors affecting the units. A large number of boreholes were drilled to reveal the 3D features of the area and cross sections were obtained. The most critical geotechnical numerical cross section that best represents the mass movements was selected and the stability of the area was analysed by finite element method in dry and water saturated conditions using Plaxis 2D and 3D Connect Edition v22 software.

Keywords

• Open pit mine
• Mass Movement
• Debris Flow
• Finite Element Method
• Back Analysis

Bir açık ocak örneğinde yamaç molozu akma mekanizmasının belirlenmesi

Öz

17 Kasım 2016 tarihinde, Türkiye'nin güneydoğusundaki Siirt ilinin Madenköy ilçesinde bulunan bir açık ocak bakır madeninde meydana gelen heyelan sonucunda 16 işçi hayatını kaybetmiştir. Bu çalışmanın temel amacı, kazanın nedenlerini araştırmak, mekanizmasını ortaya koymak ve gelecekte meydana gelebilecek bu tür kütle hareketlerine karşı hazırlıklı olmaktır. Çalışma alanı Bitlis Masifi ile başlayan Eosen yaşlı birimler ile kuzeyden başlayıp güneye doğru gençleşen Paleozoik birimlerden oluşmaktadır. Daha sonraki incelemeler hidrojeolojik koşulların ve jeolojik yapının birimleri etkileyen en önemli faktörler olduğunu göstermiştir. Çalışma alanının jeolojik, jeoteknik ve hidrojeolojik özelliklerinin belirlenmesi amacıyla çok sayıda sondaj kuyusu açılarak alanın 3 boyutlu özellikleri ortaya çıkarılmış ve kesitler elde edilmiştir. Kütle hareketlerini en iyi temsil eden kritik jeoteknik sayısal kesit seçilmiş ve bölgenin duraylılığı Plaxis 2D ve 3D Connect Edition v22 yazılımı kullanılarak kuru ve suya doygun koşullarda sonlu elemanlar yöntemi ile analiz edilmiştir.

Anahtar Kelimeler

• Açık Ocak Madeni
• Kütle hareketi
• Moloz Akması
• Sonlu Elemanlar Yöntemi
• Geri Analiz

Kaynakça

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