Researchs On Stability Analysis Methods For Rock Slope Under Excavation Blasting Load

The problem of slope stability is a well-enduring academic research in geotechnical engineering. Especially for the rock slope under the excavation blasting loads, it is an inevitable problem during the construction of the mining, road engineering, water resources and hydropower engineering etc. At present, researches in this field are still needed. Thus, it is very necessary and of great practical value for the study of rock slope stability analysis under the excavation blasting load. The main contents of this article are as follows:(1) For the rigorous Janbu method, when the number of slope slices is too much, it will do not get a safety factor. B-spline based on good smoothness, a clear expression and compactness, the matrix calculation can be used to solve the interpolation function coefficient. It is easy for programming and computes efficiently. In this paper, using B-spline interpolation function to simulate the torque between the slices is proposed. According to the example study, this approach is reasonable and right.(2) In this paper, blasting vibration safety standards are discussed. The differences between blasting vibration and natural earthquakes are analyzed. For the natural seismic waves, the frequency of acceleration time curve is low and the amplitude decays rapidly. On the other hand, for the blasting vibration wave, the frequency of acceleration time curve is high and the amplitude decays slowly. Due to this differences, the pseudo-static method and time history analysis method should be combined to analyze the slope stability under the excavation blasting load.(3) The overall downward trend direction of the three-dimensional vector sum method were discussed. According to the example study, the negative direction of ultimate shear force of the slip surface is the overall downward trend direction. Combining the dynamic finite element and three-dimensional vector sum method to analyze stability of slope under the excavation blasting load. At the same time, the process of using three-dimensional vector sum method to analyze the stability of slope under blasting load is given. According to a homogeneous rock slope example study, it shows that it is reasonable and right for using vector sum method to analyze the stability of slope under blasting load.(4) Combining the pseudo-static method and time history analysis method, and taking this method to analyze slope stability of Huangmailing open pit. The safety factor curve of the slope is been got by using actual monitoring acceleration time curve. The result is coincided with the actual situation.