A discussion on the Hoek-Brown failure criterion and suggested modifications to the criterion verified by slope stability case studies
Yakın aralıklı eklemlerle bölünmüş kaya kütlelerinin mekanik davranışının tahmini, laboratuvar deneyleri için gerekli olan örnek boyutlarının büyük olması nedeniyle kaya mekaniğinin temel sorunlarından biridir. Kaya malzemeleri ve kaya kütleleri için önerilmiş olan görgül (ampirik) yenilme ölçütleri arasında yer alan Hoek-Brown ölçütü oldukça popüler olmuştur. Ölçüt, özellikle zayıf kaya kütlelerine uygulanmasıyla ilgili bazı sınırlamaları nedeniyle, ilk kez önerildiği 1980'den bu yana farklı zamanlarda tekrar düzenlenmiş ve genişletilmiştir. 1997 yılında Jeolojik Dayanım İndeksi (GSI), kaya kütlesinde ölçek etkisini dikkate alan bir parametre olarak geliştiricileri tarafından ölçüte dahil edilmiştir. Ayrıca GSI'nın daha niceliksel şekilde belirlenebilmesi ve GSI ile ilgili girdi parametrelerinin tahmininde kullanılabilecek yöntemler konusunda 1999 yılında bu makalenin yazarları tarafından mevcut GSI Sistemi'ne yönelik bazı değişiklikler önerilmiştir. Bununla birlikte yazarlar, GSI değeri 25 ve 26 olan kaya kütlelerinin yenilme zarfları arasında ortaya çıkan bir dayanım boşluğu, belirli bir normal gerilme düzeyinde yüksek ve düşük dayanımlı kaya kütielerinin yenilme zarflarının birbirlerini kesmesi ve GSI
Hoek-Brown yenilme ölçütü üzerine bir tartışma ve şev duraylılığı vakaları ile sınanmış ölçüte ilişkin değişiklik önerileri
Estimation of the mechanical behavior of closely jointed rock masses is one of the fundamental problems in rock mechanics since the size of representative specimens is too large for laboratory testing. Among the empirical strength criteria suggested for intact rocks and rock masses, the Hoek-Brown criterion has become highly popular. Since its introduction in 1980, the criterion has been refined and expanded over the years, particularly due to some limitations in its application to poor-very poor quality rock masses. In 199,7 the Geological Strength Index (GSI) was introduced into the criterion by its originators as a scaling parameter. In addition, some modifications to the GSI System to provide a more quantitative estimate of GSI and methods of parameter estimation have also been previously suggested by the authors,of this paper in 1999. However, the authors considered that some improvements seem to be necessary in order to avoid the gap between failure envelopes of the rock masses with the GSI values between 25 and 26, intersection between failure envelopes of the rock masses of high and low strengths at a certain-normal stress level, and a uniaxial compressive strength of zero when s=0 for GSI
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- ISSN: 1301-2894
- Yayın Aralığı: 3
- Başlangıç: 1976
- Yayıncı: Hacettepe Üniversitesi Yerbilimleri Uygulama ve Araştırma Merkezi
Sayıdaki Diğer Makaleler
CO2' ce zengin çorak, Karakaya ve Gümüşkent (Nevşehir) mineralli sularının hidrojeokimyası