Abstract: The slope system is an open and multi-factor dynamic system.The establishing of grey forecasing model with high precision is of very important to analyze the evolution regularity of slope displacement and slope stability evaluation.Considering the water-softening influence of slope rock,the water-softening coefficient is introduced,water-softening total evolution equation related to the saturated water-water loss cycles is derived based on the relationship between water-softening parameters and stress-strain.The conventional threshold of the displacement increment deviation is modified based on the water-softening coefficient,so as to get the increment deviation threshold of the slope under the different deformation stage.Taken the modification value of displacement increment deviation as the identification index to identify the abnormal monitoring data and conduct data adjustment calculation,so as to establish the grey prediction model of dynamic correction of deviation threshold based on considering the influence of water-softening.The grey model established in this paper is applied to the slope engineering of Changshang open-pit tailings in Sanshandao Gold Mine,the analysis results show that the prediction results of the model is similar to the measured data,therefore,the prediction precise of the model is high,which further show that the displacement change trend in the dynamic cycle of water level fluctuation can be described effectively,and it has some important significance for studying the dynamic stability of slope.

Key words: Grey model, Slope displacement, Deviation, Water-softening coefficient