ON APPLICATIONS OF ASYMPTOTIC RELIABILITY FUNCTIONS TO THE RELIABILITY AND RISK-EVALUATION OF PIPELINES

In the reliability investigation of large systems the problem of the c omplexity of their reliability functions appears. This problem may be approximately solved by assuming that the numer of the system componen ts tends to infinity and finding the limit reliability function of the system. The solution for two-state series and parallel systems is wel l known and given for instance in 'Statistical theory of reliability a nd life testing' by Barlow and Prochan. Limit reliability functions of more complex two-state series-parallel and parallel-series systems wi th identical components are discussed by Kolowrocki (Reliability Engin eering and System Safety 1993;41:251-7). The results on limit reliabil ity functions of two-state series-parallel and parallel-series systems with different components are given by Kolowrocki (Reliability Engine ering and System Safety 1994;46:179-88). Systems with multistate compo nents are more general and play an important role in the reliability p ractice, specially in system safety analysis. Therefore in the paper, besides of the classes of limit reliability functions for nonhomogeneo us two-state systems, the classes of such functions for any large homo geneous multistate series and series-parallel systems are given. Moreo ver, some applications of the results to the reliability and risk eval uation of pipelines are presented. (C) 1998 Elsevier Science Ltd. All rights reserved.