Study on the macro mechanical parameters of spillway slope fractured rock mass in one hydropower station

A Hydropower Station is located in the middle reach of the Dadu River in southwest China. The natural slope angles are generally 40°~65° and the relative elevation drop is more than 600m. Complex different fractures such as faults, dykes and dense fracture zones due to unloading are developed. Many abutment slopes were formed during construction of the abutments. The stability of these steep and high slopes during construction and operation period plays an important role for the safe construction and operation of the hydropower station. According to the statistical distribution of joints and fractures at the construction site, the slope is divided into a number of engineering geological zones. For each zone, a stochastic fracture network and a numerical model which is close to the real state of the fractured rock mass are established by the Monte-Carlo method. The mechanical response of fractured rock masses with different sizes of numerical models is studied using FLAC3D. The REV characteristic scale is identified for rock masses in the slopes with stochastic fracture network. Numerical simulation is performed to obtain the stress-strain curve, the mechanical parameters and the strength of the jointed rock mass in the zone. A constitutive relationship reflecting the mechanical response of the jointed rock mass in the zone is established. The Comparison between the traditional method and the method in this paper has been made at the end.

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Stability Analysis of Dangerous Rocks on the Slope of a Hydropower Station

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.621 ◽

2013 ◽

Vol 405-408 ◽

pp. 621-629 ◽

Cited By ~ 1

Author(s):

Hai Feng Li ◽

Guo Xing Zhang ◽

Tao Huang ◽

Qiu Jing Zhou

Keyword(s):

Rock Mass ◽

Fractured Rock ◽

Discontinuous Deformation Analysis ◽

Hydropower Station ◽

Deformation Analysis ◽

Time Interval ◽

Block Method ◽

Fractured Rock Mass ◽

Unstable Failure ◽

The Stability

Dangerous rocks are among the most significant factors in analyzing the stability of high slopes, and are the main geological hazards on such slopes. These rocks are typical spatial blocks. The unstable failure of dangerous rocks poses evident spatial features. Consequently, their stability should be calculated by considering it as a three-dimensional (3-D) problem. In this research, the general block method of fractured rock mass and 3-D discontinuous deformation analysis (DDA) are used to study the stability of dangerous rocks on the slope of a hydropower station. The general block method of fractured rock mass is used to generate dangerous rocks and to assess the geometric mobility of blocks. The progressive unstable failure of dangerous rocks is also analyzed. Moreover, 3-D DDA is implemented to examine the stability of dangerous rocks, including the regularity of their unstable failure. The failure sequence of each batch of blocks estimated by general block theory is the same as that in the results of 3-D DDA. The decrease in the shear parameters of the structural plane shortens the time interval of failures, but increases the number and capacity of blocks.

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