INVESTIGATION OF INFLUENCE OF BERM HEIGHTS, GRADIENT OF SLOPE EXCAVATION AND GROUNDWATER DEPTHS ON SAFETY OF WEAK ROCK SLOPE

Abstract

In this study, effects of berm heights, excavation slope gradients and groundwater depths on the stability of designed excavations as well as variations on the safety factors of the excavation slopes are investigated. In the study, 3 different berm heights (5m, 10m and 15m) and 2 berms usually preferred and faced at the slope excavation applications were taken into consideration. So, for instance, for a 10 m berm height, total slope height to be analyzed will be a 30m high due to for 2 berms. In addition, depending on these 3 different berm heights (5m, 10m and 15m), 3 different slope excavation gradients (450, 550 and 650) were also defined in the modeling. Then, for these 9 different slope excavation designs, 3 different groundwater depths were also additionally attained in the analyses. Numerical seepage analyses were performed on totally 27 different modal types. Location of phreatic water seepage lines and pore water pressure values as well as safety factors of the excavation slope failure surfaces were analyzed depending on berm heights, excavation gradients and groundwater locations for 27 different excavation and slope scenarios. This study showed that when berm heights are increased, then safety of the slope excavations is decreased. 

Keywords

• Excavation Slope,Slope Stability,Berm Height,Rock,Ground Water

KAZI PALYE YÜKSEKLİĞİ, KAZI ŞEV EĞİMİ VE YERALTI SUYU DERİNLİĞİNİN DÜŞÜK MUKAVEMETLİ KAYA KAZILARININ STABİLİTESİ ÜZERİNE ETKİLERİNİN ARAŞTIRILMASI

Abstract

Bu çalışmada, Palye tasarım yüksekliklerinin, kazı şevi eğimlerinin ve yeraltı suyu konumunun projelendirilmiş kazı şevlerinin stabilitesine olan etkisi ve kazı şevi kayma güvenliklerindeki değişim dereceleri araştırılmıştır. Uygulamada çoğunlukla alınan 5m, 10m ve 15m gibi üç farklı palye yüksekliği dikkate alınmış ve toplam yamaç kazısının yine uygulamada çoklukla karşımıza çıkan iki palye oluşturulduğunda biteceği kabul edilmiştir. Örneğin 10m palye yüksekliğinde iki palye yapıldığında modellenecek ve analiz edilecek toplam yamaç kazısı yüksekliği 30m olmaktadır.  Bunun yanı sıra 3 farklı palye yüksekliğine (5m, 10m ve 15m) bağlı üç ayrı kazı şevi eğimi (450, 550 ve 650) modellenmiş ve 9 farklı kazı tasarımı için ayrıca 3 farklı yeraltı suyu derinliği etkisi dikkate alınmış tır. Toplamda 27 farklı model üzerinde yeraltı suyu nümerik sızma analizi yapılarak freatik hatların konumu ve kayaç boşluk suyu basınçları ayrı ayrı hesaplanmıştır. Hesaplanmış boşluk suyu basınçları stabilite analizlerinde kullanılarak kazı şevlerinin güvenlikleri palye yüksekliklerine, kazı şev eğimlerine ve yeraltı suyu derinliklerine bağlı olarak hesaplanmıştır. Analiz sonuçları, palye yüksekliği arttıkça kazı şevlerinin güvenliği azaldığını göstermiştir. Ayrıca yeraltı suyu derinliği ne kadar yüksek ise kayma yüzeylerine etki eden boşluk suyu basınçları o derece yüksek oluşmakta, kazı şevlerinin güvenliği azalmaktadır.

Keywords

• Kazı Şevi,Şev Güvenliği,Palye Yüksekliği,Kaya,Yeraltı Suyu

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