Procedure to Solve Mutually Dependent Fault Trees (FT with Loops)
Takeshi Matsuoka · Proceedings of the 30th European Safety and Reliability Conference and 15th Probabilistic Safety Assessment and Management Conference · 2020
This paper presents a procedure to solve mutually dependent Fault Trees in success events expression. First, explain the basic procedure by using simple dependent fault trees. Detailed analysis steps are described. Next, the procedure is applied to more complex fault trees with 3 non-linear interrelated loops. FT structures are converted into a physical system model, which satisfy Boolean equations in success events expression. The Boolean equations are solved with the aid of takeover phenomenon by considering the process of establishing loop structured operation. Finally, the solution is converted into failure expression and obtain a fault tree structure. It is shown that the representative possible solution of mutually dependent Fault Trees can be obtained by formulary method. And FT with loops can be solvable without approximation.