Computer-aided Fault Tree Construction Methods Of Automatically

Fault tree analysis (FTA) is known as a simple, effective and the most promising approach for the failure model analysis of a system. It is one of the important approaches in the probability safety analysis (PSA), and has been applied in various industries, such as the nuclear industry, the chemical industry, the electronic industry, etc. The FTA model is the base for the fault tree analysis, and since the construction of the fault tree model is time consuming, its applications had once been limited.There are a large number of computer codes have been developed for fault tree analysis. Due to its complexness and the difficulties in the realization of programming the fault tree models, the construction of a fault tree is usually made manually. With the development of the computer technology, an approach of automatic fault tree construction (AFTC) had been developed in the late 90's. PSA software with this approach could enable people to construct a fault tree more efficiently and more correctly. So far, however, there is still no any commercial software with the AFTC feature around the world.In this master's thesis, various approaches for the AFTC are summarized and assessed, and the key issues of the AFTC are discussed. One approach for the AFTC is proposed based on the graphic methodology. This approach consists of the information and the construction of the fault tree, focusing on solving the most difficult issues of AFTC, such as the active components, the loop circuit and the "direct cause". A classic example is given to demonstrate and verify the proposed approach of AFTC. Based on the VC++ and the expert programming systems, a number of data tables for the programming of AFTC are figured out, and exploratory studies for programming AFTC software are made.The achievements made with the AFTC approach would broader the applications of FTA, and would also provide a strong technical support for Living PSA.