Abstract:

Based on the instable mechanism of fully mechanized caving face with large cutting height bracket - rock system of special thick coal seam in Tongxin coal, the author explores the elements which impact the stability of fully mechanized caving face, meanwhile establishes the instable fault tree. Using triangular fuzzy function and Boolean algebra method, the author calculates the probability of the occurrence of the top event and evaluates the security of the system. The author also ranks the importance by calculating the fuzzy importance of the basic events, and thus ascertains the main elements causing the fault of fully mechanized caving face with large cutting height bracket - rock system.

Key words: fully mechanized caving face, bracket - rock system instability, fault tree, triangular fuzzy numbers