Research On Stability Analysis Of High Rock Slop And Synthetical Analysis Of Anchor Cable Reinforcement

The paper analyzes the engineering geological condition and regional geological condition of one high rock slope in southwestern China, and several limit equilibrium methods such as Sarma method, three-dimensional wedge method are adapted to evaluate the stability of the slope in various excavation and anchorage and different working conditions. The dominant parameters of the Optimal Design is analyzed in the process of the pre-stressed anchor reinforcement according to the practical condition, and the optimal anchorage angle in theory on the right bank is calculated on the basic of the selected sliding surface. The finite element method is adopted to numerically simulate and analyze the reinforcement effect of the high rock slope in various pre-stressed anchor reinforcement. The improved genetic algorithm and artificial neutral networks are used to analyze the stability of the three-dimensional wedge slope and predict the coefficient of the stability of its local buckling.Firstly, the rigid body limit equilibrium method is involved to analyze the stability of the slope including the damage instability mode across the sliding surface and local instability mode on the three-dimensional wedge blocks. The paper emphasizes the Sarma method which is to analyze sliding mode on the right LPⅧ-Ⅷsection along the unloading cracks:XL9-15 and XL316-1. The stereographic projection method is adopted to combine the cracks in the engineering geological investigation report and calculate local instability mode on the three-dimensional wedge blocks, which provides the corresponding reference data for the further reinforcement analyze and neutral networks prediction.Secondly, the paper briefly describes the system of pre-stressed anchor cable. The relevant parameters, including the angle between the cable and the horizontal plane, the anchor length, the anchor space which are important to the anchor design, are proposed to confirm the key parameters and optimal results based on the principle of optimal decision analysis. According to the practical engineering, the cable inclination angleθ(commonly known as anchoring angle in engineering) which turns into the dominant design parameters under the selected sliding surface, is used to calculate the optimal anchorage angle of each main section on right bank along the unloading cracks:XL9-15, in sliding mode.The different situation by reducing and increasing length of 20% in anchorage length, in the finite element simulation analysis process, are involved to analyze slope's relative displacement on each section on the left and right banks, the tensile stress of the first principal stress and the third principal stress and variation law of plastic zone, resulting a series of valuable results, and further analyze the reinforcement effect of the side slope.According to the practical project of a high rock slope, the paper establishes the Genetic Algorithm Optimized Back-Propagation neutral networks prediction model on the stability of the three-dimensional wedge slope. The controlled structural plane position factor-F and the factor, which involved the influence of the weight of the three-dimensional wedge slope by the structural plane orientation angle, were selected as the input variations in neural networks controlling structure. In the initialization of population concerning genetic algorithm optimize neural network weights, the paper evenly divided interval [2,2] into a small total population and randomly initialized, which ensured abundant model in initial population and enhanced the possibility of enabling genetic algorithm converge to the global optimal point. The satisfactory predictive results are calculated from predicting the stability coefficients of the local instability model on the three-dimensional wedge-shaped blocks through the improved Back-Propagation neutral networks.