تحليل احتمالي عددي پايداري استاتيكي و ديناميكي شيرواني سنگي تكيه گاه سمت راست سد و نيروگاه كارون 4

چكيده انگليسي :

Probabilistic Static and Dynamic Analysis on Slope Stability of the Right Abutment of Karun 4 Hydro Power Plant A Numerical Study Sadegh kefayati sadegh kefayati@yahoo com 1 Nov 2010 Department of Mining Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisors Alireza Baghbanan E mail bagh110@cc iut ac ir Hamid Hashemolhoseini E mail hamidh@cc iut ac ir Abstract There is not any unique solution when stability of a slope in a fractured rock mass is evaluated due to some degree of uncertainties Uncertainty occurs due to variation in mechanical properties of intact rock and discontinuities analysis tools and also geometrical properties of fractures However in fractured rock masses when there is a complex system of fractures there is a large degree of uncertainty in conceptual geometrical properties of models due to unknown parameters of fractures such as persistency Therefore probabilistic analysis is inevitable In the literature in slope stability problems they have considered continuum equivalent continuum models based on the calculated mechanical properties of rock mass using empirical methods or just considered regular joint set system as the input geometrical parameters of discrete models Stochastic DFN models present a more realistic representation of fracture network pattern The DFN models are based on stochastic representations of fracture system using the probabilistic density function of fracture parameters using Monte Carlo model formulated according to field mapping results The force acting on blocks also is estimated using numerical methods such as Distinct Element Method DEM approach A methodology development for a numerical probabilistic analysis of slope stability using DFN DEM models is the main objective of this research work In the right abutment of Karun 4 dam in Iran and in the downstream of the dam body five joint sets and one major joint have been detected According to the geometrical properties of fractures in the Karun river valley there is some potential unstable condition for this abutment A number of stochastic DFN models are generated and a series of numerical DEM modeling are performed on generated models to calculate potential block failure and measuring minimum required support patterns for dry and assumed water table static loading and also dynamic analysis The dynamic input data is based on two expected Design Basis Earthquake DBE and Maximum Credible Earthquake MCE conditions Present slope condition at right abutment in Karun 4 hydro power plant is well much with the results of slope stability analysis with dry condition Results of dry and assumed water table conditions show that the distribution of required bolt lengths follows a lognormal distribution In dry condition more than 80 percent of models need only 1614 99 m of bolts which is a bolt pattern with 2 m spacing and 12 m of length Stronger bolt pattern with 2653 49 m of bolts which is a bolt pattern with 15 m length and 1 5 m spacing for assumed water table condition is needed for 80 percent of models Dynamic analysis results indicate that MCE condition is likely to trigger sliding rock mass on major joint of slope It shows also the failure of blocks on major joints is occurred locally in DBE condition and consequently it leads to the slope to be unstable in the future Keywords Rock slope Discrete Fracture Network Probabilistic analysis Seismic behavior

كفايتي، صادق

تحليل احتمالي عددي پايداري استاتيكي و ديناميكي شيرواني سنگي تكيه گاه سمت راست سد و نيروگاه كارون 4

شيب سنگي , شبكه شكستگي مجزا , تحليل مرزه اي