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

Year 2019, Volume: 7 Issue: 4, 761 - 766, 19.12.2019

Murat Kilit , Uğur Çavuş

https://doi.org/10.21923/jesd.449554

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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