The Instability Analysis And Forecast Of High-steep Slope Of Open-pit Of Xinqiao Mine

The stability of open-pit mine slope and the unsteady slip surface are influenced by a number of complex conditions like precipitation, geological conditions, groundwater, and the excavation of the lower part of the foot of the slope. That many disasters of the open-pit instability landslide happen frequently can not only affect the project progress of mineral exploitation that causes significant economic losses, but also involve too much life and property safety that brings significant security threat to mineral exploitation.Aimed at this phenomenon, this thesis takes the Xinqiao hign-steep slope of open-pit as an example, bases on the methods of Critical Slip Field and the Grey system, analyses the slope critical slip surface, the slide exit points and safety coefficients, derives the theoretical model of prediction of slope deformation, and establishes the unsteady standard between safety coefficients and sliding displacement.Firstly, this thesis derives the slope geological conditions by scene investigation, elicits the slope’s safety coefficients, critical slip surface, and the slide exit points by the methods of Critical Slip Field(CSF). Then derives the slope’s steady degree by comparing the calculated safety coefficients and the critical values of slope’s unsteady safety coefficients. Predicts the possible influenced range of slope slide according to the location of critical slip surface and slide exit points, which provides theoretic basis for drawing the evacuated region.Secondly, this thesis utilizes monitoring equipment that setting on the side slope to measure the vertical rock mass displacement of the side slope and to measure the groundwater level near canal and the rainfall of side slope, then derives the correlation among side slope displacement, underground water and rainfall by the site monitoring data. This thesis establishes a dynamic forecasting model of monitoring the displacement of side slope according to the cumulated displacement of slope rock mass and the Grey systemic theory, and on the basis of OLS Theory and Curve Fitting Theory. Then establishes the forecasting model of improving single-point GM(1,1) to forecast the trend of side slope displacement on the basis of the traditional GM(1,1) model. Finally, the side slope secourity can be forewarned correetly according to the compare between the calculated safety coefficients and the critical values of slope’s unsteady safety coefficients, and the steady degree of slope derived fron side slope measured and forecasting displacement. Then the forewarning information makes it convenient for people making preventive measures quickly, and provides reliable theoretics basis for safety mining of diggings.