DFT based evaluation of risk probabilities for underground coal mine water inrush

Fault tree analysis(FTA) has been widely utilized as a tool for water inrush risk assessment in coal mines, and dynamic fault tree analysis(DFT) is still being studying, which takes the fact into consideration that the probability of basic events(BE) and Boolean logic will be changing. While one problem is that it's difficult to obtain failure and repair probability data at different time when simulates DFT. This study models DFT of water inrush in Chinese coal mine and invites experts to estimate the failure and repair probability of BE, then triangular fuzzy numbers are adopted to quantify experts' estimate. Using defuzzification and moment method, the shape and scale parameters of Weibull distribution about failure and repair time are achieved. The result of Monte Carlo simulation for DFT illustrates that the probability of underground coal mine water inrush is about 0.001 in 2.5years since the mine begin its capital construction.