Determination of rock mass shear strength through back analysis method: A case study

Öz

In this study, the slope failures were investigated in Avnik (Bingöl) iron open – pit mine. The slope instabilities occurred in highly weathered phyllite and schist units. The back analyses were carried out considering the limit equilibrium method and the shear strength parameters. While determining shear strength parameters via limit equilibrium method Hoek – Brown failure criterion was used. The GSI values (35 – 32) obtained by back analyses and GSI values (41 – 35) determined by field survey are compatible with each other. Hoek – Brown parameters for phyllite and schist units, which were obtained by back analyses are mb: 0.147, 0.173 s: 3.305e-005, 8.566e-005 a: 0.516 – 0.511, respectively.

Anahtar Kelimeler

• Back analysis
• Limit equilibrium method
• Hoek – Brown failure criterion
• Open - pit
• Slope stability

Kaya kütle makaslama dayanımının geri analiz yöntemi ile belirlenmesi: Bir vaka analizi

Öz

Bu çalışma kapsamında, Avnik (Bingöl) demir açık ocak işletmesinde meydana gelen şev duraysızlıkları incelenmiştir. Duraysızlıklar, ileri derecede kırıklı çatlaklı fillit ve şist birimlerinde meydana gelmiştir. Limit denge analiz yöntemi ile geri analizler yapılmış ve duraysız şevlerin makaslama dayanım parametreleri belirlenmiştir. Limit denge yöntemi ile makaslama dayanım parametreleri belirlenirken Hoek – Brown yenilme ölçütü kullanılmıştır. Geri analizler neticesine elde edilen GSI değerleri (35 - 32) ile arazi çalışmalarından elde edilen GSI değerleri (41 – 35) birbirleri ile uyumludur. Geri analizler neticesinde fillit ve şist birimleri için Hoek – Brown parametreleri sırası ile mb:0.147, 0.173 s: 3.305e-005, 8.566e-005 a: 0.516, 0.511 olarak hesaplanmıştır.

Anahtar Kelimeler

• Geri analiz
• Limit denge analizi
• Hoek-Brown yenilme ölçütü
• Açık ocak işletmesi
• Şev duraylılığı

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