The stability of high and steep slope is greatly influenced by underneath ore body mining. Considering random features of the mechanical parameters of rock and blasting loads, take the slope stability as the research object, the dynamic reliability evaluation methods is established based on first-excursion failure theory caused by blasting vibration influence. Applying the proposed theory to analyze the Da MingCao high and steep slope stability with blasting mining of the backfilling ore of ancient slag at Zhao Tong lead-zinc mine in Yunnan province. Simulation results of dynamic reliability p...